Difference between revisions of "The RIMO"

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{{DISPLAYTITLE:The 2018 instrument model}}
 
== Overview ==
 
== Overview ==
 +
 +
The RIMO, or "Reduced Instrument Model" is a FITS file or a set of FITS files containing selected instrument characteristics that are needed by users who work with the released data products.  It is described in detail in "The HFI and LFI RIMO Interface Control Documents" (see also {{PlanckPapers|planck2014-a03}} and {{PlanckPapers|planck2014-a08}}). There are two RIMOs, one for each instrument (the HFI RIMO consists of several parts), which follow the same overall structure, but differ in the details. 
 +
 +
The type of data in the RIMO can be of several forms.
 +
 +
; Parameter : These are scalars, to give properties such as a noise level or a representative beam FWHM.
 +
; Vector or Table : These give, e.g., filter transmission profiles, noise power spectra, or beam window functions.  When possible (specifically when they are of equal length, such as the noise power spectra), an effort is made to put them together into a table, otherwise they are given as separate vectors.
 +
; Image : These 2-D "flat" arrays give, e.g., the beam correlation matrices.
 +
 +
The FITS file begins with the primary header, which contains some keywords that are mainly for internal use.  The different types of data are written into different BINTABLE (for parameters and tables) or IMAGE (for 2-D arrays) extensions, as described below. 
 +
 +
<span style="color:#0000ee">Attn regarding HFI_RIMO:</span> For the HFI 2018 (legacy) release, which contains only maps, the RIMO contains only the merged bandpasses necessary to describe those maps; this is because the RIMO of a release contains information regarding the products of the release. In practice, for the this release, these bandpasses are a simple average of the bandpasses of the detectors used in each map (which can be found in RIMO of the 2015 release) without any weighting (i.e., SWBs have the same weight as PSBs).  As a consequence, the next section describing the contents, applies almost exclusively to the LFI RIMO
 +
 +
 +
=== File Names ===
 +
 +
; HFI 2018 RIMO: {{PLASingleFile|fileType=rimo|name=HFI_RIMO_R3.00.fits|link=HFI_RIMO_R3.00.fits}}
 +
; LFI 2018 RIMO: {{PLASingleFile|fileType=rimo|name=LFI_RIMO_R3.00.fits|link=LFI_RIMO_R3.31.fits}}
 +
 +
== Detector-level parameter data (LFI only) ==
 +
 +
The detector parameter data are stored in the form of a table giving the parameter values for each detector.  The table columns (whose names are in ''BOLD ITALICS'') are as follows.
 +
 +
; Bolometer name - ''DETECTOR'' : These are the detector names. For HFI they are of the form ''217-3'' for SWBs or ''100-3b'' for PSBs, and for LFI they are of the form 27M or 18S. There are 52 HFI detectors and 22 LFI detectors.
 +
 +
; Focal plane geometry parameters - ''PHI_UV'', ''THETA_UV'', and ''PSI_UV'' : These parameters give the geometry of the focal plane, or the positions of the detectors in the focal plane in the Dxx reference frame. The angles that give the rotation of the beam pattern from a fiducial orientation (forward beam direction (<i>z</i>-axis) pointing along the telescope line of sight, with <i>y</i>-axis aligned with the nominal scan direction) to their positions in the focal plane. The fiducial position is that given by the Star Tracker. All angles are in radians. These parameters are derived from observations of bright planets; see [[Detector_pointing | Detector pointing]] for details.
 +
 +
; Polarization parameters - ''PSI_POL'', ''EPSILON'' :These are the direction of maximum polarization (defined with the beam in the fiducial orientation described above, that is, before rotation onto the detector position), and the cross-polarization contamination (or leakage).  These values are determined from ground-based measurements.
 +
 +
; Beam parameters - ''FWHM'', ''ELLIPTICITY'', ''POSANG'' : These are the mean FWHM of the scanning beam (in arcmin), the beam ellipticity (no units), and the position angle of the beam major axis. The scanning beam is that recovered from the observation of bright planets. Details are in the [[Beams]] section.
 +
 +
; Noise parameters - ''NET'' (LFI), ''NET_TOT'' (HFI), ''NET_WHT'' (HFI), ''NET_OOF'' (HFI), ''F_KNEE'', ''ALPHA'', ''F_MIN'' (LFI), ''F_MAX'' (LFI) : Three NETs are given: one determined from the total noise (rms of the noise timeline, excluding glitched data and other non-valid data); one determined from the white noise level of the noise amplitude spectrum; and the last determined from fitting a ''1/<i>f</i>'' noise spectrum, described by the function &sigma;<sup>2</sup>(1+(<i>f</i><sub>knee</sub>/<i>f</i>)<sup>&alpha;</sup>) to the noise <i>power</i> spectrum.  In the latter, the ''F_KNEE'' and ''ALPHA'' parameters are the frequency where the ''1/<i>f</i>'' component meets the white noise level, and the slope of the former.  Since this is defined in power, the slope is about twice the slope of the amplitude spectrum. The NETs are in units of K<sub>CMB</sub>.&radic;s for 30-353 GHz, and MJy sr<sup>-1</sup>.&radic;s for 545 and 857 GHz.
 +
 +
; Detector sampling frequency - ''F_SAMP'' : This is self-explanatory.
 +
 +
In the HFI RIMO, this table includes entries for the RTS bolometers (143-8 and 545-3), which are approximate or 0.00 when not evaluated.
 +
 +
== Map-level parameter data (LFI only) ==
 +
 +
The map-level data table contains the effective beam solid angle (total, as well as integrated out to different multiples of the beam FWHM) and noise information.  It is written into a BINTABLE extension named ''MAP_PARAMS'', whose structure is different for HFI and LFI and is as follows. The noise description below is very simplified; a more complete rendition can be obtained from the half-ring maps.  For characterization of systematic effects, the survey differences should be used.
 +
 +
; ''FREQUENCY'' (String) : A 3-digit string giving the reference frequency in GHz, i.e., of the form "030".
 +
; ''FWHM'' (Real*8) : FWHM of a Gaussian beam having the same (total) solid angle, in arcmin.
 +
; ''NOISE'' (Real*8) : This is the average noise in K.s<sup>1/2</sup>.
 +
; ''CENTRALFREQ'' (Real*4) : This is the average central frequency in GHz.
 +
; ''FWHM_EFF'', ''FWHM_EFF_SIGMA'' (Real*4) : This is the average FWHM of the effective beam, in arcmin, and its dispersion.
 +
; ''ELLIPTICITY_EFF'', ''ELLIPTICITY_EFF_SIGMA'' (Real*4) : This is the average ellipticity and its dispersion.
 +
; ''SOLID_ANGLE_EFF'', ''SOLID_ANGLE_EFF_SIGMA'' (Real*4) : This is the average full beam solid angle, in arcmin<sup>2</sup>, and its dispersion.
 +
 +
== Effective band transmission profiles ==
 +
 +
The effective filter bandpasses are given in different BINTABLE extensions.  The extension is named ''BANDPASS_{name}'', where ''name'' specifies the detector or the maps. For the latter, the bandpasses are a weighted average of the bandpasses of the detectors that are used to build the map, using the same weights that are used in the mapmaking.  These merged bandpasses are given for the full channel maps (all detectors within each frequency channel) and for the PSBs only in each frequency channel for HFI. For details on the measurements and compilation of the bandpasses  see {{PlanckPapers|planck2013-p03d}}.  For details on the measurements and compilation of the LFI bandpasses see {{PlanckPapers|planck2014-a05||Planck-2015-A05}}.
 +
 +
The bandpasses are given as 4-column tables containing the following elements.
 +
 +
=== HFI ===
 +
 +
; ''WAVENUMBER'' (Real*4) : The wavenumber in cm<sup>-1</sup>, with conversion to GHz being accomplished by multiplying by 10<sup>-7</sup>c [mks].
 +
; ''TRANSMISSION'' (Real*4) : The transmission (normalized to 1 at the maximum for HFI).
 +
; ''FLAG'' (Integer) : A flag indicating if the data point is an independent frequency data point (normally the case, "flag=0"), or an FTS instrument line shape (ILS)-interpolated data point ("flag=1").  In the latter case the frequency data have been over-sampled by about a factor of 10 to assist in CO component-separation efforts {{PlanckPapers|planck2013-p03d}}{{PlanckPapers|planck2013-p03a}}.
 +
 +
Note that there is no "ERROR" column in this delivery.  This is because the error given previously was simply a small statistical measurement error for each point and did not include other potentially more importantc (but not measured, and not measurable) systematic errors, which could affect the overall shape of the transmission profile.
 +
 +
=== LFI ===
 +
 +
; ''WAVENUMBER'' (Real*8) : The wavenumber in GHz.
 +
; ''TRANSMISSION'' (Real*8) : The transmission (normalized to have an integral of 1 for LFI).
 +
; ''UNCERTAINITY'' (Real*4) : The statistical <math>1\sigma</math> uncertainty for the transmission profile (not provided for LFI).
 +
; ''FLAG'' (Character) : a flag, not used now by the LFI.
 +
 +
The number of rows will differ among the different extensions, but are the same, by construction, within each extension.
 +
 +
== Beam window functions (LFI only) ==
 +
 +
'''Please note that the HFI beam window functions are no longer delivered in a RIMO: see the [[Beam Window Functions | Beam_Window_Functions ]] section for the HFI version of these products.'''
 +
 +
Beam window functions and associated error descriptions are written into a BINTABLE for each "detection unit", where "detection unit" consists of an auto- or a cross-product (for HFI only) of one (or two) frequency maps or detset maps used in the likelihood.  They are explicitly listed below.
 +
 +
* the three LFI frequency channels (auto-products only), producing three extensions, namely
 +
** 30, 44, 70;
 +
* the three LFI 70GHz detector pairs (auto-products only), producing three extensions, namely
 +
** 18-23, 19-22, 20-21.
 +
 +
The extension names are of the form "BEAMWF_U1XU2", where "U1" and "U2" are one (possibly the same) detection unit from one of the main groups above (i.e., there are no cross-products between detsets and frequency channels, or between HFI and LFI). Each extension contains the following columns.
 +
; ''NOMINAL'' (HFI, Real*4) : The beam window function proper.
 +
; ''BL'' (LFI, Real*4) : The beam window function proper.
 +
; ''EIGEN_n'' (Real*4, <i>n</i>=1-5 for the HFI, <i>n</i>=1-4 for the LFI): The five/four corresponding error modes.
 +
 +
The following keywords give further information, only for the HFI.
 +
; ''NMODES'' (Integer) : The number of EIGEN_* modes.
 +
; ''LMIN'' and ''LMAX'' (Integer) : The starting and ending (both included) multipoles of the vectors NOMINAL and EIGEN_* .
 +
; ''LMIN_EM'' and ''LMAX_EM'' (Integer) : These give the range of the valid samples of the EIGEN_* vectors. Here "LMAX_EM" is always less than or equal to "LMAX". On the range "LMAX_EM"+1 to "LMAX" the values of EIGEN_* are set to NaN, while the values of NOMINAL are a Gaussian extrapolation of the lower multipole window function, only provided for convenience.
 +
; ''CORRMAT'' (string) : The name of the extension containing the corresponding beam correlation matrix.
 +
 +
Finally, also see the "COMMENT" of each header for more specific details.
 +
 +
==Appendices==
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* [[UC_CC_Tables | Unit correction and color correction tables]]
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== Previous Releases: 2020 (NPIPE), 2015 and 2013 Instrument Models ==
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<div class="toccolours mw-collapsible mw-collapsed" style="background-color: #9ef542;width:80%">
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'''The 2020 Instrument Model'''
 +
<div class="mw-collapsible-content">
 +
The NPIPE release includes a new issuing of the LFI and HFI reduced instrument models (RIMOs).  These RIMOs reflect the NPIPE-optimized detector noise weights, symmetrized pointing in each polarized horn, and the improved polarization parameters for HFI.  The information is summarized in the following table.
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[[File:Hfi params.png|400px|frameless|none|HFI polarization parameters]]
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The instrument model files are called ''RIMO_LFI_NPIPE.fits'' and ''RIMO_HFI_NPIPE.fits'' and are a part of the auxiliary data file, {{PLASingleFile|fileType=rimo|name=PLANCK_RIMO_TF_R4.00.tar.gz|link=PLANCK_RIMO_TF_R4.00.tar.gz}}.
 +
 +
</div>
 +
</div>
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 +
<div class="toccolours mw-collapsible mw-collapsed" style="background-color: #FFDAB9;width:80%">
 +
'''The 2015 Instrument Model'''
 +
<div class="mw-collapsible-content">
 +
 +
'' Overview ''
 +
 +
The RIMO, or "Reduced Instrument Model" is a FITS file or a set of FITS files containing selected instrument characteristics that are needed by users who work with the released data products.  It is described in detail in "The HFI and LFI RIMO Interface Control Documents" (see also {{PlanckPapers|planck2014-a03}} and {{PlanckPapers|planck2014-a08}}). There are two RIMOs, one for each instrument (the HFI RIMO consists of several parts), which follow the same overall structure, but differ in the details.  The type of data in the RIMO can be of several forms.
 +
 +
; Parameter : These are scalars, to give properties such as a noise level or a representative beam FWHM.
 +
; Vector or Table : These give, e.g., filter transmission profiles, noise power spectra, or beam window functions.  When possible (specifically when they are of equal length, such as the noise power spectra), an effort is made to put them together into a table, otherwise they are given as separate vectors.
 +
; Image : These 2-D "flat" arrays give, e.g., the beam correlation matrices.
 +
 +
The FITS file begins with the primary header, which contains some keywords that are mainly for internal use.  The different types of data are written into different BINTABLE (for parameters and tables) or IMAGE (for 2-D arrays) extensions, as described below. 
 +
 +
The HFI-RIMO separates the beam window functions and associated data from the main set of parameters; this is because the beam window functions are delivered for two cases covering 100% and 75% of the sky, as described in detail below.
 +
 +
''' File Names '''
 +
 +
; HFI 2015 RIMO: {{PLASingleFile|fileType=rimo|name=HFI_RIMO_R2.00.fits|link=HFI_RIMO_R2.00.fits}}
 +
; LFI 2015 RIMO: {{PLASingleFile|fileType=rimo|name=LFI_RIMO_R2.50.fits|link=LFI_RIMO_R2.50.fits}}
 +
 +
'' Detector-level parameter data ''
 +
 +
The detector parameter data are stored in the form of a table giving the parameter values for each detector.  The table columns (whose names are in ''BOLD ITALICS'') are as follows.
 +
 +
; Bolometer name - ''DETECTOR'' : These are the detector names. For HFI they are of the form ''217-3'' for SWBs or ''100-3b'' for PSBs, and for LFI they are of the form 27M or 18S. There are 52 HFI detectors and 22 LFI detectors.
 +
 +
; Focal plane geometry parameters - ''PHI_UV'', ''THETA_UV'', and ''PSI_UV'' : These parameters give the geometry of the focal plane, or the positions of the detectors in the focal plane in the Dxx reference frame. The angles that give the rotation of the beam pattern from a fiducial orientation (forward beam direction (<i>z</i>-axis) pointing along the telescope line of sight, with <i>y</i>-axis aligned with the nominal scan direction) to their positions in the focal plane. The fiducial position is that given by the Star Tracker. All angles are in radians. These parameters are derived from observations of bright planets; see [[Detector_pointing | Detector pointing]] for details.
 +
 +
; Polarization parameters - ''PSI_POL'', ''EPSILON'' :These are the direction of maximum polarization (defined with the beam in the fiducial orientation described above, that is, before rotation onto the detector position), and the cross-polarization contamination (or leakage).  These values are determined from ground-based measurements.
 +
 +
; Beam parameters - ''FWHM'', ''ELLIPTICITY'', ''POSANG'' : These are the mean FWHM of the scanning beam (in arcmin), the beam ellipticity (no units), and the position angle of the beam major axis. The scanning beam is that recovered from the observation of bright planets. Details are in the [[Beams]] section.
 +
 +
; Noise parameters - ''NET'' (LFI), ''NET_TOT'' (HFI), ''NET_WHT'' (HFI), ''NET_OOF'' (HFI), ''F_KNEE'', ''ALPHA'', ''F_MIN'' (LFI), ''F_MAX'' (LFI) : Three NETs are given: one determined from the total noise (rms of the noise timeline, excluding glitched data and other non-valid data); one determined from the white noise level of the noise amplitude spectrum; and the last determined from fitting a ''1/<i>f</i>'' noise spectrum, described by the function &sigma;<sup>2</sup>(1+(<i>f</i><sub>knee</sub>/<i>f</i>)<sup>&alpha;</sup>) to the noise <i>power</i> spectrum.  In the latter, the ''F_KNEE'' and ''ALPHA'' parameters are the frequency where the ''1/<i>f</i>'' component meets the white noise level, and the slope of the former.  Since this is defined in power, the slope is about twice the slope of the amplitude spectrum. The NETs are in units of K<sub>CMB</sub>.&radic;s for 30-353 GHz, and MJy sr<sup>-1</sup>.&radic;s for 545 and 857 GHz.
 +
 +
; Detector sampling frequency - ''F_SAMP'' : This is self-explanatory.
 +
 +
In the HFI RIMO, this table includes entries for the RTS bolometers (143-8 and 545-3), which are approximate or 0.00 when not evaluated.
 +
 +
'' Map-level parameter data ''
 +
 +
The map-level data table contains the effective beam solid angle (total and out to different multiples of the beamFWHM) and noise information.  It is written into a BINTABLE extension named ''MAP_PARAMS'' whose structure is different for HFI and LFI and is as follows. The noise description below is very simplified; a more accurate rendition can be obtained from the half-ring maps.  Regarding the characterization of systematics, the user should use the survey differences.
 +
 +
''' HFI '''
 +
 +
; ''FREQUENCY'' (String) : a 3-digit string giving the reference frequency in GHz, i.e., of the form ''217''
 +
; ''OMEGA_F'', ''OMEGA_F_ERR'' (Real*4) : the full beam solid angle and its uncertainty, in armin<sup>2</sup>
 +
; ''OMEGA_1'', ''OMEGA_1_DISP'' (Real*4) : the beam solid angle out to 1FWHM, and its dispersion, in arcmin<sup>2</sup>
 +
; ''OMEGA_2'', ''OMEGA_2_DISP'' (Real*4) : the beam solid angle out to 2FWHM, and its dispersion, in arcmin<sup>2</sup>
 +
; ''FWHM'' (Real*4) : FWHM of a Gaussian beam having the same (total) solid angle, in armin<sup>2</sup>. This is the best value for source flux determination
 +
; ''FWHMGAUS'' (Real*4) : FWHM derived from best Gaussian fit to beam maps, in armin<sup>2</sup>. This is the best value for source identification
 +
; ''NOISE'' (Real*4) : This is the typical noise/valid observation sample as derived from the high-''l'' spectra of the half-ring maps, in the units of the corresponding map
 +
 +
For the Omega columns, the 'DISP' (for ''dispersion'') column gives an estimate of the spatial variation as a function of position on the sky. This is the variation induced by combining the scanning beam determined from the planet observations with the scanning strategy, as described in [[Beams]].
 +
 +
''' LFI '''
 +
 +
; ''FREQUENCY'' (String) : a 3-digit string giving the reference frequency in GHz, i.e., of the form ''030, 044, 070''
 +
; ''FWHM'' (Real*8) : FWHM of a Gaussian beam having the same (total) solid angle, in arcmin
 +
; ''NOISE'' (Real*8) : This is the average noise in T<math>\cdot</math>s<sup>1/2</sup>
 +
; ''CENTRALFREQ'' (Real*4) : This is the average central frequency in GHz
 +
; ''FWHM_EFF'', ''FWHM_EFF_SIGMA'' (Real*4) : This is the average FWHM of the effective beam, in arcmin, and its dispersion
 +
; ''ELLIPTICITY_EFF'', ''ELLIPTICITY_EFF_SIGMA'' (Real*4) : This is the average ellipticity and its dispersion
 +
; ''SOLID_ANGLE_EFF'', ''SOLID_ANGLE_EFF_SIGMA'' (Real*4) : This is the average full beam solid angle, in arcmin<sup>2</sup>, and its dispersion
 +
 +
'' Effective band transmission profiles ''
 +
 +
The effective filter bandpasses are given in different BINTABLE extensions.  The extension is named ''BANDPASS_{name}'', where ''name'' specifies the detector or the maps. For the latter, the bandpasses are a weighted average of the bandpasses of the detectors that are used to build the map, using the same weights that are used in the mapmaking.  These merged bandpasses are given for the full channel maps (all detectors of the frequency channel) and for the PSBs only in each frequency channel for HFI. For details on the measurements and compilation of the bandpasses  see {{PlanckPapers|planck2013-p03d}}.  For details on the measurements and compilation of the LFI bandpasses see {{PlanckPapers|planck2014-a05||Planck-2015-A05}}.
 +
 +
The bandpasses are given as 4-column tables containing:
 +
 +
''' HFI '''
 +
 +
; ''WAVENUMBER'' (Real*4) : the wavenumber in cm-1, conversion to GHz is accomplished by multiplying by <math>10^{-7}c</math> [mks].
 +
; ''TRANSMISSION'' (Real*4) : the transmission (normalized to 1 at the max for HFI)
 +
; ''ERROR'' (Real*4) : the statistical <math>1\sigma</math> uncertainty for the transmission profile.
 +
; ''FLAG'' (Integer) : a flag indicating if the data point is an independent frequency data point (nominally the case), or an FTS instrument line shape (ILS)-interpolated data point.  The frequency data has been over-sampled by a factor of ~10 to assist in CO component separation efforts {{PlanckPapers|planck2013-p03d}}{{PlanckPapers|planck2013-p03a}}.
 +
 +
The number of rows will differ among the different extensions, but are the same, by construction, within each extension.  Tables with the unit conversion coefficients and color correction factors for the HFI detectors (and LFI in some instances), including uncertainty estimates based on the uncertainty of the HFI detector spectral response are given in [[UC_CC_Tables | this appendix]].
 +
 +
''' LFI '''
 +
 +
; ''WAVENUMBER'' (Real*8) : the wavenumber in GHz.
 +
; ''TRANSMISSION'' (Real*8) : the transmission (normalized to have an integral of 1 for LFI)
 +
; ''UNCERTAINITY'' (Real*4) : the statistical <math>1\sigma</math> uncertainty for the transmission profile (not provided for LFI)
 +
; ''FLAG'' (Character) : a flag, not used by now by the LFI
 +
 +
The number of rows will differ among the different extensions, but are the same, by construction, within each extension.
 +
 +
'' Detector noise spectra (Only HFI)''
 +
 +
; HFI: these are the ring noise amplitude spectra averaged over about 5000 rings in order to give a representative spectrum. The spectra of all 50 valid bolometers are given in a single table. The spectra have a maximum frequency (Nyquist) of 90.18685Hz, also given the the ''F_NYQ'' keyword, and are built over 32768 points, giving a lower frequency of 2.75 mHz.
 +
 +
 +
The keyword ''F_NYQ'' gives the Nyquist frequency, and can be used together with the number of points in the spectrum to reconstruct the frequency scale. The BINTABLE has Ndetector columns by Npoints rows.
 +
 +
 +
'' Beam Window Functions ''
 +
 +
Beam window functions and associated error descriptions are written into a BINTABLE for each ''detection unit'', where ''detection unit'' consists of an auto or a cross product (for HFI only) of one (or two) frequency maps or detset maps used in the likelihood.  Here they are:
 +
 +
; ''For the HFI'':
 +
* the 6 HFI frequency channels + 3 psb-only subsets, producing 45 extensions
 +
** 100, 143, 217, 353, 545, 857, 143p, 217p, 353p
 +
* 26 detsets, producing 351 extensions; the detsets used are, by frequency channel:
 +
** 100-DS1, 100-DS2,
 +
** 143-DS1, 143-DS2, 143-5, 143-6, 143-7,
 +
** 217-DS1, 217-DS2, 217-1, 217-2, 217-3, 217-4,
 +
** 353-DS1, 353-DS2, 353-1, 353-2, 353-7, 353-8,
 +
** 545-1,  545-2,  545-4,
 +
** 857-1,  857-2,  857-3, 857-4
 +
 +
Note for HFI these (and also the associated covariance matrices) are given in separate files named ''HFI_RIMO-Beams-nnnpc_Rm.nn.fits'', where nnn is 100 or 075 and indicates the percentage (pc) of the sky included (see [[Frequency_Maps#Galactic_Plane_masks | Masks]] and [[Beams#Impact_of_sky_cut|Beams]] sections).
 +
 +
; ''For the LFI'':
 +
* the 3 LFI frequency channels (auto- products only), producing 3 extensions
 +
** 30, 44, 70
 +
* the 3 LFI 70GHz detector pairs (auto- products only), producing 3 extensions
 +
** 18-23, 19-22, 20-21
 +
 +
The extension names are of the form ''BEAMWF_U1XU2'' where U1 and U2 are one (possibly the same) detection unit from one of the main groups above (i.e. there are no cross products between detsets and frequency channels, or between HFI and LFI). Each extension contains the columns:
 +
; ''NOMINAL'' (HFI, Real*4) : the beam window function proper,
 +
; ''BL'' (LFI, Real*4) : the beam window function proper,
 +
; ''EIGEN_n'' (Real*4, n=1-5 for the HFI, n=1-4 for the LFI): the five/four corresponding error modes.
 +
 +
and the following keywords give further information, only for the HFI:
 +
; ''NMODES'' (Integer) : the number of EIGEN_* modes,
 +
; ''LMIN'' and ''LMAX'' (Integer) : the starting and ending (both included) multipoles of the vectors NOMINAL and EIGEN_*
 +
; ''LMIN_EM'' and ''LMAX_EM'' (Integer) : that give the range of the valid samples of the EIGEN_* vectors. Here ''LMAX_EM'' is always less than or equal to ''LMAX''. On the range ''LMAX_EM''+1 to ''LMAX'' the values of EIGEN_* are set to NaN, while the values of NOMINAL only are a Gaussian extrapolation of the lower multipole window function, only provided for convenience.
 +
; ''CORRMAT'' (string) : the name of the extension containing the corresponding beam correlation matrix
 +
 +
And finally see also the ''COMMENTs'' of each header for more specific details.
 +
 +
'' Beam Correlation Matrix ''
 +
 +
Two beam correlation matrices are given for the HFI, in two ''IMAGE'' extensions:
 +
; ''CORRBEAM_FREQ'' (Real*8) : for the frequency channels (21 units), 105x015 pixel matrix,
 +
; ''CORRBEAM_DSET'' (Real*8) : for the detsets (351 units), 1755x1755 pixel matrix
 +
Each is a symmetric matrix with 1-valued diagonal, made of NBEAMS*NBEAMS blocks, each block being NMODES*NMODES in size.  The n$^{th}$ row- (and column-) block entry relates to the B(l) model whose name is indicated in ROWn = BEAMWF_U1XU2 keywords, and the corresponding eigenmodes are stored in a HDU of the same name. 
 +
 +
Each extension contains also the following keywords:
 +
; ''NDETS'' (Integer) : the number of detector units
 +
; ''NBEAMS'' (Integer) : the number of beams = NSETS * (NSETS+1) / 2
 +
; ''NMODES'' (Integer) : here 5
 +
; ''L_PLUS'' (Integer) : Eigenmode > 0 to break degeneracies
 +
; ''BLOCKn'' (string) : for n=1-NBEAMS, gives the name of the extension containing the beam WF and error eigenmodes for the nth block
 +
and some other ones for internal data checking and traceability
 +
 +
No beam correlation matrices are produced by the LFI by now.  And for HFI these, together with the beam window functions, are given in a file separate from the main RIMO (see subsection above).
 +
 +
''Appendices''
 +
 +
* [[UC_CC_Tables | Unit correction and color correction tables]]
 +
 +
 +
</div>
 +
</div>
 +
 +
<div class="toccolours mw-collapsible mw-collapsed" style="background-color: #EEE8AA;width:80%">
 +
'''The 2013 Instrument Model'''
 +
<div class="mw-collapsible-content">
 +
 +
'' Overview ''
  
 
The RIMO, or ''Reduced Instrument Model'' is a FITS file containing selected instrument characteristics that are needed by users who work with the released data products.  It is described in detail in ''The HFI and LFI RIMO ICD'' (ref).  There will be two RIMOs, one for each instrument, which will follow the same overall structure, but will differ in the details.  The type of data in the RIMO can be:
 
The RIMO, or ''Reduced Instrument Model'' is a FITS file containing selected instrument characteristics that are needed by users who work with the released data products.  It is described in detail in ''The HFI and LFI RIMO ICD'' (ref).  There will be two RIMOs, one for each instrument, which will follow the same overall structure, but will differ in the details.  The type of data in the RIMO can be:
Line 5: Line 283:
 
; Parameter : namely scalars to give properties such as a noise level or a representative beam FWHM
 
; Parameter : namely scalars to give properties such as a noise level or a representative beam FWHM
 
; Table : to give, e.g., filter transmission profiles or noise power spectra
 
; Table : to give, e.g., filter transmission profiles or noise power spectra
−
; Map : namely 2-D "flat" maps, to give, e.g., the main beam shape
+
; Image : namely 2-D "flat" array, to give, e.g., the beam correlation matrices
  
−
The different types of data are written into different BINTABLE extensions of the FITS file, and these are described below.
+
The FITS file begins with primary header that contains some keywords that mainly for internal use and no data.  The different types of data are written into different BINTABLE (for parameters and tables) or IMAGE (for 2-D arrays) extensions, as described below.
  
−
-----------
+
''' File Names '''
  
−
<!--
+
; HFI: {{PLASingleFile|fileType=rimo|name=HFI_RIMO_R1.10.fits|link=HFI_RIMO_R1.10.fits}}
−
== Detector-level parameter data ==
+
; LFI: {{PLASingleFile|fileType=rimo|name=LFI_RIMO_R1.12.fits|link=LFI_RIMO_R1.12.fits}}
  
−
<center>
 
−
{| border="1" cellspacing="10" cellpadding="8" align="center" style="background:yellow; color:maroon; font-size:150%"  width="600px"
 
−
! There  are no detector-level products in the first release,
 
  
−
so there will be no detector-level parameters in the accompanying RIMO … … TBC. 
+
<!--
 +
'' Detector-level parameter data ''
  
−
This section is currently included for completeness
+
There  are no detector-level products in the first release.
−
|}
 
−
</center>
 
  
  
Line 29: Line 303:
 
; Bolometer name - ''DETECTOR'' : These are the detector names. For HFI these will be of the form ''217-3'' for SWBs or ''100-3b'' for PSBs, and for LFI they will have the form 27M or 18S. There are 52 HFI detectors and 22 LFI detectors.
 
; Bolometer name - ''DETECTOR'' : These are the detector names. For HFI these will be of the form ''217-3'' for SWBs or ''100-3b'' for PSBs, and for LFI they will have the form 27M or 18S. There are 52 HFI detectors and 22 LFI detectors.
  
−
; Focal plane geometry parameters - ''PHI_UV'', ''THETA_UV'', and ''PSI_UV'' : These parameters give the geometry of the focal plane, or the positions of the detectors in the focal plane. The angles that give the rotation of the beam pattern from a fiducial orientation (forward beam direction (z-axis) pointing along the telescope line of sight, with y-axis aligned with the nominal scan direction) to their positions in the focal plane. The fiducial position is that given by the Star Tracker. All angles are in radians. These parameters are derived from observations of bright planets; see [[Pointing&Beams | Detectors pointing & beam]] for details.
+
; Focal plane geometry parameters - ''PHI_UV'', ''THETA_UV'', and ''PSI_UV'' : These parameters give the geometry of the focal plane, or the positions of the detectors in the focal plane. The angles that give the rotation of the beam pattern from a fiducial orientation (forward beam direction (z-axis) pointing along the telescope line of sight, with y-axis aligned with the nominal scan direction) to their positions in the focal plane. The fiducial position is that given by the Star Tracker. All angles are in radians. These parameters are derived from observations of bright planets; see [[Detector_pointing | Detector pointing]] for details.
  
 
; Polarization parameters - ''PSI_POL'', ''EPSILON'' :These are the direction of maximum polarization, defined with the beam in the fiducial orientation described above, that is, before rotation onto the detector position, and the cross-polarization contamination (or leakage).  These values are determined from ground-based measurements.
 
; Polarization parameters - ''PSI_POL'', ''EPSILON'' :These are the direction of maximum polarization, defined with the beam in the fiducial orientation described above, that is, before rotation onto the detector position, and the cross-polarization contamination (or leakage).  These values are determined from ground-based measurements.
  
−
; Beam parameters - ''FWHM'', ''ELLIPTICITY'', ''POSANG'' : These are the mean FWHM of the scanning beam (in arcmin, the beam ellipticity (no units), and the position angle of the beam major axis. The scanning beam is that recovered from the observation of bright planets; details in [[Pointing&Beams | Detectors pointing & beam]].
+
; Beam parameters - ''FWHM'', ''ELLIPTICITY'', ''POSANG'' : These are the mean FWHM of the scanning beam (in arcmin, the beam ellipticity (no units), and the position angle of the beam major axis. The scanning beam is that recovered from the observation of bright planets; details in [[Beams]] section.
  
 
; Noise parameters - ''NET_TOT'', ''NET_WHT'', ''F_KNEE'', ''ALPHA'' : Two NETs are given: one determined from the total noise (rms of the noise timeline) and one determined from the white noise level of the noise spectrum.  The ''F_KNEE'' and ''ALPHA'' parameters are the frequency where the ''1/f'' noise component meets the white noise level, and the slope of the former.  The NETs are in units of Kcmb or MJy/sr * sqrt(s). These values are determined from the signal timelines as described in [[TOI processing|TOI processing]] chapter.
 
; Noise parameters - ''NET_TOT'', ''NET_WHT'', ''F_KNEE'', ''ALPHA'' : Two NETs are given: one determined from the total noise (rms of the noise timeline) and one determined from the white noise level of the noise spectrum.  The ''F_KNEE'' and ''ALPHA'' parameters are the frequency where the ''1/f'' noise component meets the white noise level, and the slope of the former.  The NETs are in units of Kcmb or MJy/sr * sqrt(s). These values are determined from the signal timelines as described in [[TOI processing|TOI processing]] chapter.
Line 39: Line 313:
 
In the HFI RIMO, this table includes entries for the RTS bolometers (143-8 and 545-3), which are approximate or 0.00 when not evaluated.
 
In the HFI RIMO, this table includes entries for the RTS bolometers (143-8 and 545-3), which are approximate or 0.00 when not evaluated.
  
−
The basic structure of the BINTABLE extension is as follows:
+
-->
 +
 
 +
'' Map-level parameter data ''
 +
 
 +
The map-level data table contains the effective beam solid angle (total and out to different multiples of the beamFWHM) and noise information.  It is written into a BINTABLE extension named ''MAP_PARAMS'' whose structure is different for HFI and LFI and is as follows. The noise description below is very simplified; a more accurate rendition can be obtained from the half-ring maps.  Regarding the characterization of systematics, the user should use the survey differences.
 +
 
 +
''' HFI '''
  
−
-->
+
; ''FREQUENCY'' (String) : a 3-digit string giving the reference frequency in GHz, i.e., of the form ''217''
 +
; ''OMEGA_F'', ''OMEGA_F_ERR'' (Real*4) : the full beam solid angle and its uncertainty, in armin<sup>2</sup>
 +
; ''OMEGA_1'', ''OMEGA_1_DISP'' (Real*4) : the beam solid angle out to 1FWHM, and its dispersion, in arcmin<sup>2</sup>
 +
; ''OMEGA_2'', ''OMEGA_2_DISP'' (Real*4) : the beam solid angle out to 2FWHM, and its dispersion, in arcmin<sup>2</sup>
 +
; ''FWHM'' (Real*4) : FWHM of a Gaussian beam having the same (total) solid angle, in armin<sup>2</sup>. This is the best value for source flux determination
 +
; ''FWHMGAUS'' (Real*4) : FWHM derived from best Gaussian fit to beam maps, in armin<sup>2</sup>. This is the best value for source identification
 +
; ''NOISE'' (Real*4) : This is the typical noise/valid observation sample as derived from the high-''l'' spectra of the half-ring maps, in the units of the corresponding map
 +
 
 +
For the Omega columns, the 'DISP' (for ''dispersion'') column gives an estimate of the spatial variation as a function of position on the sky. This is the variation induced by combining the scanning beam determined from the planet observations with the scanning strategy, as described in [[Beams]].
  
−
== Map-level parameter data ==
+
''' LFI '''
  
−
The map-level data table contains the effective beam solid angle (total and out to different multiples of the beamFWHM) and noise information as follows:
+
; ''FREQUENCY'' (String) : a 3-digit string giving the reference frequency in GHz, i.e., of the form ''030, 044, 070''
 +
; ''FWHM'' (Real*8) : FWHM of a Gaussian beam having the same (total) solid angle, in arcmin
 +
; ''NOISE'' (Real*8) : This is the average noise in T<math>\cdot</math>s<sup>1/2</sup>
 +
; ''CENTRALFREQ'' (Real*4) : This is the average central frequency in GHz
 +
; ''FWHM_EFF'', ''FWHM_EFF_SIGMA'' (Real*4) : This is the average FWHM of the effective beam, in arcmin, and its dispersion
 +
; ''ELLIPTICITY_EFF'', ''ELLIPTICITY_EFF_SIGMA'' (Real*4) : This is the average ellipticity and its dispersion
 +
; ''SOLID_ANGLE_EFF'', ''SOLID_ANGLE_EFF_SIGMA'' (Real*4) : This is the average full beam solid angle, in arcmin<sup>2</sup>, and its dispersion
  
−
; ''FREQUENCY'' : a 3-digit string giving the reference frequency in GHz, i.e., of the form ''044'' or ''217''
+
'' Effective band transmission profiles ''
−
; ''Omega_total'': total beam solid angle in armin^2
 
−
; ''Omega_1fwhm'' : beam solid angle out to 1FWHM in arcmin^2
 
−
; ''Omega_2fwhm'' :  beam solid angle out to 2FWHM in arcmin^2
 
−
; ''FWHM_eff'' : FWHM of a Gaussian beam having the same (total) solid angle, in sr. This is the best value for source flux determination
 
−
; ''FWHM_gauss'' : FWHM derived from best Gaussian fit to beam maps, in sr. This is the best value for source identification
 
−
; ''NOISE'' : This is the typical noise/valid observation sample as derived from an appropriate combination of the NETs of the valid detectors used in the map.
 
  
−
For the Omega columns, the 'DISP' (for ''dispersion'') column gives an estimate of the spatial variation as a function of position on the sky. This is the variation induced by combining the scanning beam determined from the planet observations with the scanning strategy, as described in [[Pointing&Beams | Detectors pointing & beam]].
+
The effective filter bandpasses are given in different BINTABLE extensions.  The extension is named ''BANDPASS_{name}'', where ''name'' specified the frequency channel.  In the case of the maps, the bandpasses are a weighted average of the bandpasses of the detectors that are used to build the map.  For details see {{PlanckPapers|planck2013-p03d}}. The bandpasses are given as 4-column tables containing:
  
−
The BINTABLE extension has the following structure
+
''' HFI '''
  
 +
; ''WAVENUMBER'' (Real*4) : the wavenumber in cm-1, conversion to GHz is accomplished by multiplying by <math>10^{-7}c</math> [mks].
 +
; ''TRANSMISSION'' (Real*4) : the transmission (normalized to 1 at the max for HFI)
 +
; ''ERROR'' (Real*4) : the statistical <math>1\sigma</math> uncertainty for the transmission profile.
 +
; ''FLAG'' (Integer) : a flag indicating if the data point is an independent frequency data point (nominally the case), or an FTS instrument line shape (ILS)-interpolated data point.  The frequency data has been over-sampled by a factor of ~10 to assist in CO component separation efforts {{PlanckPapers|planck2013-p03a}}{{PlanckPapers|planck2013-p03d}}.
  
−
== Effective band transmission profiles ==
+
The number of rows will differ among the different extensions, but are the same, by construction, within each extension.  Tables with the unit conversion coefficients and color correction factors for the HFI detectors (and LFI in some instances), including uncertainty estimates based on the uncertainty of the HFI detector spectral response are given in [[UC_CC_Tables | this appendix]].
  
−
The effective filter bandpasses are given in different BINTABLE extensions.  The extension is named ''BANDPASS_{name}'', where ''name'' specified the frequency channel.  In the case of the maps, the bandpasses are a weighted average of the bandpasses of the detectors that are used to build the map.  For details see <cite>#planck2013-p03d</cite>.  The bandpasses are given as 4-column tables containing:
+
''' LFI '''
  
−
; ''WAVENUMBER'' : the wavenumber in cm-1, conversion to GHz is accomplished by multiplying by <math>10^{-7}c</math> [mks].
+
; ''WAVENUMBER'' (Real*8) : the wavenumber in GHz.
−
; ''TRANSMISSION'' : the transmission (normalized to 1 at the max for HFI and to have an integral of 1 for LFI)
+
; ''TRANSMISSION'' (Real*8) : the transmission (normalized to have an integral of 1 for LFI)
−
; ''ERROR'' : the statistical <math>1-\sigma</math> uncertainty for the transmission profile (not provided for LFI).
+
; ''UNCERTAINITY'' (Real*4) : the statistical <math>1\sigma</math> uncertainty for the transmission profile (not provided for LFI)
−
; ''FLAG'' : a flag indicating if the data point is an independent frequency data point (nominally the case), or an FTS instrument line shape (ILS)-interpolated data point.  The frequency data has been over-sampled by a factor of ~10 to assist in CO component separation efforts <cite>#planck2013-p03a, #planck2013-p03d</cite>.
+
; ''FLAG'' (Character) : a flag, not used by now by the LFI
  
 
The number of rows will differ among the different extensions, but are the same, by construction, within each extension.  
 
The number of rows will differ among the different extensions, but are the same, by construction, within each extension.  
  
 
<!--
 
<!--
−
== Detector noise spectra ==
+
'' Detector noise spectra ''
  
−
The noise power spectra are the result of the ''detnoise'' pipeline. 
+
There are no detector-level noise data in the RIMO for this release
  
 
; HFI: these are the ring noise spectra averaged for rings NN to MM in order to give a representative spectrum. The spectra of all 50 valid bolometers are given in a single table.
 
; HFI: these are the ring noise spectra averaged for rings NN to MM in order to give a representative spectrum. The spectra of all 50 valid bolometers are given in a single table.
−
 
 
; LFI : TBW
 
; LFI : TBW
  
 
The keyword ''F_NYQ'' gives the Nyquist frequency, and can be used together with the number of points in the spectrum to reconstruct the frequency scale. The BINTABLE has the following structure:
 
The keyword ''F_NYQ'' gives the Nyquist frequency, and can be used together with the number of points in the spectrum to reconstruct the frequency scale. The BINTABLE has the following structure:
 +
-->
  
 +
'' Beam Window Functions ''
  
−
== Beam Window Functions ==
+
Beam window functions and associated error descriptions are written into a BINTABLE for each ''detection unit'', where ''detection unit'' consists of an auto or a cross product (for HFI only) of one (or two) frequency maps or detset maps used in the likelihood.  Here they are:  
−
 
 
−
Beam window functions and associated error descriptions are written into a BINTABLE for each ''detection unit'', where ''detection unit'' consists of an auto or a cross product of one or two frequency maps or detset maps used in the likelihood.  Here they are:  
 
  
 +
; ''For the HFI'':
 
* the 6 HFI frequency channels, producing 21 extensions
 
* the 6 HFI frequency channels, producing 21 extensions
 
** 100, 143, 217, 353, 545, 857
 
** 100, 143, 217, 353, 545, 857
Line 97: Line 389:
 
** 857-1,  857-2,  857-3, 857-4
 
** 857-1,  857-2,  857-3, 857-4
  
−
and the extension names are of the form  
+
; ''For the LFI'':
 +
* the 3 LFI frequency channels, producing 3 extensions
 +
** 30, 44, 70
 +
 
 +
 
 +
and the extension names are of the form ''BEAMWF_U1XU2'' where U1 and U2 are one (possibly the same) detection unit from one of the main groups above (i.e. there are no cross products between detsets and frequency channels, or between HFI and LFI). Each extension contains the columns:
 +
; ''NOMINAL'' (Real*4) : the beam window function proper,
 +
; ''EIGEN_n'' (Real*4, n=1-5 for the HFI, n=1-4 for the LFI): the five/four corresponding error modes.
  
−
BEAM_''U1''X''U2''
+
and the following keywords give further information, only for the HFI:
 +
; ''NMODES'' (Integer) : the number of EIGEN_* modes,
 +
; ''LMIN'' and ''LMAX'' (Integer) : the starting and ending (both included) multipoles of the vectors NOMINAL and EIGEN_*
 +
; ''LMIN_EM'' and ''LMAX_EM'' (Integer) : that give the range of the valid samples of the EIGEN_* vectors. Here ''LMAX_EM'' is always less than or equal to ''LMAX''. On the range ''LMAX_EM''+1 to ''LMAX'' the values of EIGEN_* are set to NaN, while the values of NOMINAL only are a Gaussian extrapolation of the lower multipole window function, only provided for convenience.
 +
; ''CORRMAT'' (string) : the name of the extension containing the corresponding beam correlation matrix
  
−
where U1 and U2 are one (possibly the same) detection unit from the list above.
+
'' Beam Correlation Matrix ''
  
 +
Two beam correlation matrices are given for the HFI, in two ''IMAGE'' extensions:
 +
; ''CORRBEAM_FREQ'' (Real*8) : for the frequency channels (21 units), 105x015 pixel matrix,
 +
; ''CORRBEAM_DSET'' (Real*8) : for the detsets (351 units), 1755x1755 pixel matrix
 +
Each is a symmetric matrix with 1-valued diagonal, made of NBEAMS*NBEAMS blocks, each block being NMODES*NMODES in size.  The n$^{th}$ row- (and column-) block entry relates to the B(l) model whose name is indicated in ROWn = BEAMWF_U1XU2 keywords, and the corresponding eigenmodes are stored in a HDU of the same name. 
  
 +
Each extension contains also the following keywords:
 +
; ''NDETS'' (Integer) : the number of detector units
 +
; ''NBEAMS'' (Integer) : the number of beams = NSETS * (NSETS+1) / 2
 +
; ''NMODES'' (Integer) : here 5
 +
; ''L_PLUS'' (Integer) : Eigenmode > 0 to break degeneracies
 +
; ''BLOCKn'' (string) : for n=1-NBEAMS, gives the name of the extension containing the beam WF and error eigenmodes for the nth block
 +
and some other ones for internal data checking and traceability
  
 +
No beam correlation matrices are produced by the LFI by now.
  
−
Each extension contains:
+
''Appendices''
−
* a ''NOMINAL'' column (Real*4) with the window function proper,
 
−
* five ''EIGEN_n'' columns (Real*4), of error modes.
 
−
* a keyword ''NUMVECT'' (Integer) specified the number of eigenmode vectors, and
 
−
* keywords ''LMIN'' and ''LMAX'' which give the length of nominal vector
 
−
* keywords ''LMIN_EM'' and ''LMAX_EM'' that give the range of the valid samples of the eigenmode vectors. Here ''LMAX_EM'' is always less than or equal to ''LMAX'', and the values between ''LMAX_EM''+1 and LMAX is set to NaN
 
  
 +
* [[UC_CC_Tables | Unit correction and color correction tables]]
  
−
An example of the FITS header is <span style="color:red">(Preliminary - to be updated)</span>:
 
  
−
;-----------------------------------------------------------------------------
 
−
; EXTENSION 11: BEAM_143_DS1X143_5
 
−
;-----------------------------------------------------------------------------
 
−
XTENSION= 'BINTABLE'          / binary table extension                         
 
−
BITPIX  =                    8 / array data type                               
 
−
NAXIS  =                    2 / number of array dimensions                   
 
−
NAXIS1  =                  24 / length of dimension 1                         
 
−
NAXIS2  =                4001 / length of dimension 2                         
 
−
PCOUNT  =                    0 / number of group parameters                   
 
−
GCOUNT  =                    1 / number of groups                             
 
−
TFIELDS =                    6 / number of table fields                       
 
−
TTYPE1  = 'NOMINAL '                                                           
 
−
TFORM1  = 'E      '                                                           
 
−
TTYPE2  = 'EIGEN_0 '                                                           
 
−
TFORM2  = 'E      '                                                           
 
−
TTYPE3  = 'EIGEN_1 '                                                           
 
−
TFORM3  = 'E      '                                                           
 
−
TTYPE4  = 'EIGEN_2 '                                                           
 
−
TFORM4  = 'E      '                                                           
 
−
TTYPE5  = 'EIGEN_3 '                                                           
 
−
TFORM5  = 'E      '                                                           
 
−
TTYPE6  = 'EIGEN_4 '                                                           
 
−
TFORM6  = 'E      '                                                           
 
−
EXTNAME = 'BEAM_143_DS1X143_5' / extension name                               
 
−
NUMVECT =                    5 / Number of eigenvectors                       
 
−
END
 
  
 +
</div>
 +
</div>
  
−
== Beam Correlation Matrix ==
+
== References ==
  
−
Two of these matrices are given, one for the frequency channels (21x21) and one for the detsets (351x351). Each is a symmetric matrix with 1-valued diagonal, made of NBEAMS*NBEAMS blocks, each block being NMODES*NMODES in size.  Each row- (and column-) block entry relates to the B(l) model whose name is indicated in ROW* keywords below, and the corresponding eigenmodes are stored in a HDU of the same name. 
+
<References />
  
−
The header is of the form <span style="color:red">(Preliminary - to be updated)</span>::
 
  
−
;-----------------------------------------------------------------------------
+
[[Category:Mission products|003]]
−
; EXTENSION 381: CORRBEAM_DET
 
−
;-----------------------------------------------------------------------------
 
−
XTENSION= 'IMAGE  '          /                                               
 
−
EXTNAME = 'CORRBEAM_DET'      /                                               
 
−
BITPIX  =                  -32 / IEEE single precision floating point         
 
−
NAXIS  =                    2 /                                               
 
−
NAXIS1  =                1755 /                                               
 
−
NAXIS2  =                1755 /                                               
 
−
DATE    = '2012-11-23'        / Creation date (CCYY-MM-DD) of FITS header     
 
−
  …
 
−
NDETS  =                  26 / number of detector assemblies                 
 
−
NBEAMS  =                  351 / number of beams = NDETS*(NDETS+1)/2           
 
−
NMODES  =                    5 / number of eigen modes for each beam B(l)     
 
−
DATAMIN =            -0.979880 / minimum value (should be >=-1)               
 
−
DATAMAX =              1.00000 / maximum value (should be 1)                   
 
−
ROW1    = 'BEAM_100-DS1x100-DS1' / block #1 on row (or column)                 
 
−
ROW2    = 'BEAM_100-DS1x100-DS2' / block #2 on row (or column)                 
 
−
ROW3    = 'BEAM_100-DS1x143-DS1' / block #3 on row (or column)                 
 
−
...
 
−
ROW350  = 'BEAM_857-3x857-4'  / block #350 on row (or column)                 
 
−
ROW351  = 'BEAM_857-4x857-4'  / block #351 on row (or column)                 
 
−
END
 
−
[[CAtegory:Mission science products|003]]
 

Latest revision as of 11:50, 22 June 2021

Overview[edit]

The RIMO, or "Reduced Instrument Model" is a FITS file or a set of FITS files containing selected instrument characteristics that are needed by users who work with the released data products. It is described in detail in "The HFI and LFI RIMO Interface Control Documents" (see also Planck-2015-A02[1] and Planck-2015-A07[2]). There are two RIMOs, one for each instrument (the HFI RIMO consists of several parts), which follow the same overall structure, but differ in the details.

The type of data in the RIMO can be of several forms.

Parameter 
These are scalars, to give properties such as a noise level or a representative beam FWHM.
Vector or Table 
These give, e.g., filter transmission profiles, noise power spectra, or beam window functions. When possible (specifically when they are of equal length, such as the noise power spectra), an effort is made to put them together into a table, otherwise they are given as separate vectors.
Image 
These 2-D "flat" arrays give, e.g., the beam correlation matrices.

The FITS file begins with the primary header, which contains some keywords that are mainly for internal use. The different types of data are written into different BINTABLE (for parameters and tables) or IMAGE (for 2-D arrays) extensions, as described below.

Attn regarding HFI_RIMO: For the HFI 2018 (legacy) release, which contains only maps, the RIMO contains only the merged bandpasses necessary to describe those maps; this is because the RIMO of a release contains information regarding the products of the release. In practice, for the this release, these bandpasses are a simple average of the bandpasses of the detectors used in each map (which can be found in RIMO of the 2015 release) without any weighting (i.e., SWBs have the same weight as PSBs). As a consequence, the next section describing the contents, applies almost exclusively to the LFI RIMO


File Names[edit]

HFI 2018 RIMO
HFI_RIMO_R3.00.fits
LFI 2018 RIMO
LFI_RIMO_R3.31.fits

Detector-level parameter data (LFI only)[edit]

The detector parameter data are stored in the form of a table giving the parameter values for each detector. The table columns (whose names are in BOLD ITALICS) are as follows.

Bolometer name - DETECTOR 
These are the detector names. For HFI they are of the form 217-3 for SWBs or 100-3b for PSBs, and for LFI they are of the form 27M or 18S. There are 52 HFI detectors and 22 LFI detectors.
Focal plane geometry parameters - PHI_UV, THETA_UV, and PSI_UV 
These parameters give the geometry of the focal plane, or the positions of the detectors in the focal plane in the Dxx reference frame. The angles that give the rotation of the beam pattern from a fiducial orientation (forward beam direction (z-axis) pointing along the telescope line of sight, with y-axis aligned with the nominal scan direction) to their positions in the focal plane. The fiducial position is that given by the Star Tracker. All angles are in radians. These parameters are derived from observations of bright planets; see Detector pointing for details.
Polarization parameters - PSI_POL, EPSILON 
These are the direction of maximum polarization (defined with the beam in the fiducial orientation described above, that is, before rotation onto the detector position), and the cross-polarization contamination (or leakage). These values are determined from ground-based measurements.
Beam parameters - FWHM, ELLIPTICITY, POSANG 
These are the mean FWHM of the scanning beam (in arcmin), the beam ellipticity (no units), and the position angle of the beam major axis. The scanning beam is that recovered from the observation of bright planets. Details are in the Beams section.
Noise parameters - NET (LFI), NET_TOT (HFI), NET_WHT (HFI), NET_OOF (HFI), F_KNEE, ALPHA, F_MIN (LFI), F_MAX (LFI) 
Three NETs are given: one determined from the total noise (rms of the noise timeline, excluding glitched data and other non-valid data); one determined from the white noise level of the noise amplitude spectrum; and the last determined from fitting a 1/f noise spectrum, described by the function σ2(1+(fknee/f)α) to the noise power spectrum. In the latter, the F_KNEE and ALPHA parameters are the frequency where the 1/f component meets the white noise level, and the slope of the former. Since this is defined in power, the slope is about twice the slope of the amplitude spectrum. The NETs are in units of KCMB.√s for 30-353 GHz, and MJy sr-1.√s for 545 and 857 GHz.
Detector sampling frequency - F_SAMP 
This is self-explanatory.

In the HFI RIMO, this table includes entries for the RTS bolometers (143-8 and 545-3), which are approximate or 0.00 when not evaluated.

Map-level parameter data (LFI only)[edit]

The map-level data table contains the effective beam solid angle (total, as well as integrated out to different multiples of the beam FWHM) and noise information. It is written into a BINTABLE extension named MAP_PARAMS, whose structure is different for HFI and LFI and is as follows. The noise description below is very simplified; a more complete rendition can be obtained from the half-ring maps. For characterization of systematic effects, the survey differences should be used.

FREQUENCY (String) 
A 3-digit string giving the reference frequency in GHz, i.e., of the form "030".
FWHM (Real*8) 
FWHM of a Gaussian beam having the same (total) solid angle, in arcmin.
NOISE (Real*8) 
This is the average noise in K.s1/2.
CENTRALFREQ (Real*4) 
This is the average central frequency in GHz.
FWHM_EFF, FWHM_EFF_SIGMA (Real*4) 
This is the average FWHM of the effective beam, in arcmin, and its dispersion.
ELLIPTICITY_EFF, ELLIPTICITY_EFF_SIGMA (Real*4) 
This is the average ellipticity and its dispersion.
SOLID_ANGLE_EFF, SOLID_ANGLE_EFF_SIGMA (Real*4) 
This is the average full beam solid angle, in arcmin2, and its dispersion.

Effective band transmission profiles[edit]

The effective filter bandpasses are given in different BINTABLE extensions. The extension is named BANDPASS_{name}, where name specifies the detector or the maps. For the latter, the bandpasses are a weighted average of the bandpasses of the detectors that are used to build the map, using the same weights that are used in the mapmaking. These merged bandpasses are given for the full channel maps (all detectors within each frequency channel) and for the PSBs only in each frequency channel for HFI. For details on the measurements and compilation of the bandpasses see Planck-2013-IX[3]. For details on the measurements and compilation of the LFI bandpasses see Planck-2015-A05[4].

The bandpasses are given as 4-column tables containing the following elements.

HFI[edit]

WAVENUMBER (Real*4) 
The wavenumber in cm-1, with conversion to GHz being accomplished by multiplying by 10-7c [mks].
TRANSMISSION (Real*4) 
The transmission (normalized to 1 at the maximum for HFI).
FLAG (Integer) 
A flag indicating if the data point is an independent frequency data point (normally the case, "flag=0"), or an FTS instrument line shape (ILS)-interpolated data point ("flag=1"). In the latter case the frequency data have been over-sampled by about a factor of 10 to assist in CO component-separation efforts Planck-2013-IX[3]Planck-2013-XIII[5].

Note that there is no "ERROR" column in this delivery. This is because the error given previously was simply a small statistical measurement error for each point and did not include other potentially more importantc (but not measured, and not measurable) systematic errors, which could affect the overall shape of the transmission profile.

LFI[edit]

WAVENUMBER (Real*8) 
The wavenumber in GHz.
TRANSMISSION (Real*8) 
The transmission (normalized to have an integral of 1 for LFI).
UNCERTAINITY (Real*4) 
The statistical [math]1\sigma[/math] uncertainty for the transmission profile (not provided for LFI).
FLAG (Character) 
a flag, not used now by the LFI.

The number of rows will differ among the different extensions, but are the same, by construction, within each extension.

Beam window functions (LFI only)[edit]

Please note that the HFI beam window functions are no longer delivered in a RIMO: see the Beam_Window_Functions section for the HFI version of these products.

Beam window functions and associated error descriptions are written into a BINTABLE for each "detection unit", where "detection unit" consists of an auto- or a cross-product (for HFI only) of one (or two) frequency maps or detset maps used in the likelihood. They are explicitly listed below.

  • the three LFI frequency channels (auto-products only), producing three extensions, namely
    • 30, 44, 70;
  • the three LFI 70GHz detector pairs (auto-products only), producing three extensions, namely
    • 18-23, 19-22, 20-21.

The extension names are of the form "BEAMWF_U1XU2", where "U1" and "U2" are one (possibly the same) detection unit from one of the main groups above (i.e., there are no cross-products between detsets and frequency channels, or between HFI and LFI). Each extension contains the following columns.

NOMINAL (HFI, Real*4) 
The beam window function proper.
BL (LFI, Real*4) 
The beam window function proper.
EIGEN_n (Real*4, n=1-5 for the HFI, n=1-4 for the LFI)
The five/four corresponding error modes.

The following keywords give further information, only for the HFI.

NMODES (Integer) 
The number of EIGEN_* modes.
LMIN and LMAX (Integer) 
The starting and ending (both included) multipoles of the vectors NOMINAL and EIGEN_* .
LMIN_EM and LMAX_EM (Integer) 
These give the range of the valid samples of the EIGEN_* vectors. Here "LMAX_EM" is always less than or equal to "LMAX". On the range "LMAX_EM"+1 to "LMAX" the values of EIGEN_* are set to NaN, while the values of NOMINAL are a Gaussian extrapolation of the lower multipole window function, only provided for convenience.
CORRMAT (string) 
The name of the extension containing the corresponding beam correlation matrix.

Finally, also see the "COMMENT" of each header for more specific details.

Appendices[edit]

Previous Releases: 2020 (NPIPE), 2015 and 2013 Instrument Models[edit]

The 2020 Instrument Model

The NPIPE release includes a new issuing of the LFI and HFI reduced instrument models (RIMOs). These RIMOs reflect the NPIPE-optimized detector noise weights, symmetrized pointing in each polarized horn, and the improved polarization parameters for HFI. The information is summarized in the following table.

HFI polarization parameters

The instrument model files are called RIMO_LFI_NPIPE.fits and RIMO_HFI_NPIPE.fits and are a part of the auxiliary data file, PLANCK_RIMO_TF_R4.00.tar.gz.

The 2015 Instrument Model

Overview

The RIMO, or "Reduced Instrument Model" is a FITS file or a set of FITS files containing selected instrument characteristics that are needed by users who work with the released data products. It is described in detail in "The HFI and LFI RIMO Interface Control Documents" (see also Planck-2015-A02[1] and Planck-2015-A07[2]). There are two RIMOs, one for each instrument (the HFI RIMO consists of several parts), which follow the same overall structure, but differ in the details. The type of data in the RIMO can be of several forms.

Parameter 
These are scalars, to give properties such as a noise level or a representative beam FWHM.
Vector or Table 
These give, e.g., filter transmission profiles, noise power spectra, or beam window functions. When possible (specifically when they are of equal length, such as the noise power spectra), an effort is made to put them together into a table, otherwise they are given as separate vectors.
Image 
These 2-D "flat" arrays give, e.g., the beam correlation matrices.

The FITS file begins with the primary header, which contains some keywords that are mainly for internal use. The different types of data are written into different BINTABLE (for parameters and tables) or IMAGE (for 2-D arrays) extensions, as described below.

The HFI-RIMO separates the beam window functions and associated data from the main set of parameters; this is because the beam window functions are delivered for two cases covering 100% and 75% of the sky, as described in detail below.

File Names

HFI 2015 RIMO
HFI_RIMO_R2.00.fits
LFI 2015 RIMO
LFI_RIMO_R2.50.fits

Detector-level parameter data

The detector parameter data are stored in the form of a table giving the parameter values for each detector. The table columns (whose names are in BOLD ITALICS) are as follows.

Bolometer name - DETECTOR 
These are the detector names. For HFI they are of the form 217-3 for SWBs or 100-3b for PSBs, and for LFI they are of the form 27M or 18S. There are 52 HFI detectors and 22 LFI detectors.
Focal plane geometry parameters - PHI_UV, THETA_UV, and PSI_UV 
These parameters give the geometry of the focal plane, or the positions of the detectors in the focal plane in the Dxx reference frame. The angles that give the rotation of the beam pattern from a fiducial orientation (forward beam direction (z-axis) pointing along the telescope line of sight, with y-axis aligned with the nominal scan direction) to their positions in the focal plane. The fiducial position is that given by the Star Tracker. All angles are in radians. These parameters are derived from observations of bright planets; see Detector pointing for details.
Polarization parameters - PSI_POL, EPSILON 
These are the direction of maximum polarization (defined with the beam in the fiducial orientation described above, that is, before rotation onto the detector position), and the cross-polarization contamination (or leakage). These values are determined from ground-based measurements.
Beam parameters - FWHM, ELLIPTICITY, POSANG 
These are the mean FWHM of the scanning beam (in arcmin), the beam ellipticity (no units), and the position angle of the beam major axis. The scanning beam is that recovered from the observation of bright planets. Details are in the Beams section.
Noise parameters - NET (LFI), NET_TOT (HFI), NET_WHT (HFI), NET_OOF (HFI), F_KNEE, ALPHA, F_MIN (LFI), F_MAX (LFI) 
Three NETs are given: one determined from the total noise (rms of the noise timeline, excluding glitched data and other non-valid data); one determined from the white noise level of the noise amplitude spectrum; and the last determined from fitting a 1/f noise spectrum, described by the function σ2(1+(fknee/f)α) to the noise power spectrum. In the latter, the F_KNEE and ALPHA parameters are the frequency where the 1/f component meets the white noise level, and the slope of the former. Since this is defined in power, the slope is about twice the slope of the amplitude spectrum. The NETs are in units of KCMB.√s for 30-353 GHz, and MJy sr-1.√s for 545 and 857 GHz.
Detector sampling frequency - F_SAMP 
This is self-explanatory.

In the HFI RIMO, this table includes entries for the RTS bolometers (143-8 and 545-3), which are approximate or 0.00 when not evaluated.

Map-level parameter data

The map-level data table contains the effective beam solid angle (total and out to different multiples of the beamFWHM) and noise information. It is written into a BINTABLE extension named MAP_PARAMS whose structure is different for HFI and LFI and is as follows. The noise description below is very simplified; a more accurate rendition can be obtained from the half-ring maps. Regarding the characterization of systematics, the user should use the survey differences.

HFI

FREQUENCY (String) 
a 3-digit string giving the reference frequency in GHz, i.e., of the form 217
OMEGA_F, OMEGA_F_ERR (Real*4) 
the full beam solid angle and its uncertainty, in armin2
OMEGA_1, OMEGA_1_DISP (Real*4) 
the beam solid angle out to 1FWHM, and its dispersion, in arcmin2
OMEGA_2, OMEGA_2_DISP (Real*4) 
the beam solid angle out to 2FWHM, and its dispersion, in arcmin2
FWHM (Real*4) 
FWHM of a Gaussian beam having the same (total) solid angle, in armin2. This is the best value for source flux determination
FWHMGAUS (Real*4) 
FWHM derived from best Gaussian fit to beam maps, in armin2. This is the best value for source identification
NOISE (Real*4) 
This is the typical noise/valid observation sample as derived from the high-l spectra of the half-ring maps, in the units of the corresponding map

For the Omega columns, the 'DISP' (for dispersion) column gives an estimate of the spatial variation as a function of position on the sky. This is the variation induced by combining the scanning beam determined from the planet observations with the scanning strategy, as described in Beams.

LFI

FREQUENCY (String) 
a 3-digit string giving the reference frequency in GHz, i.e., of the form 030, 044, 070
FWHM (Real*8) 
FWHM of a Gaussian beam having the same (total) solid angle, in arcmin
NOISE (Real*8) 
This is the average noise in T[math]\cdot[/math]s1/2
CENTRALFREQ (Real*4) 
This is the average central frequency in GHz
FWHM_EFF, FWHM_EFF_SIGMA (Real*4) 
This is the average FWHM of the effective beam, in arcmin, and its dispersion
ELLIPTICITY_EFF, ELLIPTICITY_EFF_SIGMA (Real*4) 
This is the average ellipticity and its dispersion
SOLID_ANGLE_EFF, SOLID_ANGLE_EFF_SIGMA (Real*4) 
This is the average full beam solid angle, in arcmin2, and its dispersion

Effective band transmission profiles

The effective filter bandpasses are given in different BINTABLE extensions. The extension is named BANDPASS_{name}, where name specifies the detector or the maps. For the latter, the bandpasses are a weighted average of the bandpasses of the detectors that are used to build the map, using the same weights that are used in the mapmaking. These merged bandpasses are given for the full channel maps (all detectors of the frequency channel) and for the PSBs only in each frequency channel for HFI. For details on the measurements and compilation of the bandpasses see Planck-2013-IX[3]. For details on the measurements and compilation of the LFI bandpasses see Planck-2015-A05[4].

The bandpasses are given as 4-column tables containing:

HFI

WAVENUMBER (Real*4) 
the wavenumber in cm-1, conversion to GHz is accomplished by multiplying by [math]10^{-7}c[/math] [mks].
TRANSMISSION (Real*4) 
the transmission (normalized to 1 at the max for HFI)
ERROR (Real*4) 
the statistical [math]1\sigma[/math] uncertainty for the transmission profile.
FLAG (Integer) 
a flag indicating if the data point is an independent frequency data point (nominally the case), or an FTS instrument line shape (ILS)-interpolated data point. The frequency data has been over-sampled by a factor of ~10 to assist in CO component separation efforts Planck-2013-IX[3]Planck-2013-XIII[5].

The number of rows will differ among the different extensions, but are the same, by construction, within each extension. Tables with the unit conversion coefficients and color correction factors for the HFI detectors (and LFI in some instances), including uncertainty estimates based on the uncertainty of the HFI detector spectral response are given in this appendix.

LFI

WAVENUMBER (Real*8) 
the wavenumber in GHz.
TRANSMISSION (Real*8) 
the transmission (normalized to have an integral of 1 for LFI)
UNCERTAINITY (Real*4) 
the statistical [math]1\sigma[/math] uncertainty for the transmission profile (not provided for LFI)
FLAG (Character) 
a flag, not used by now by the LFI

The number of rows will differ among the different extensions, but are the same, by construction, within each extension.

Detector noise spectra (Only HFI)

HFI
these are the ring noise amplitude spectra averaged over about 5000 rings in order to give a representative spectrum. The spectra of all 50 valid bolometers are given in a single table. The spectra have a maximum frequency (Nyquist) of 90.18685Hz, also given the the F_NYQ keyword, and are built over 32768 points, giving a lower frequency of 2.75 mHz.


The keyword F_NYQ gives the Nyquist frequency, and can be used together with the number of points in the spectrum to reconstruct the frequency scale. The BINTABLE has Ndetector columns by Npoints rows.


Beam Window Functions

Beam window functions and associated error descriptions are written into a BINTABLE for each detection unit, where detection unit consists of an auto or a cross product (for HFI only) of one (or two) frequency maps or detset maps used in the likelihood. Here they are:

For the HFI
  • the 6 HFI frequency channels + 3 psb-only subsets, producing 45 extensions
    • 100, 143, 217, 353, 545, 857, 143p, 217p, 353p
  • 26 detsets, producing 351 extensions; the detsets used are, by frequency channel:
    • 100-DS1, 100-DS2,
    • 143-DS1, 143-DS2, 143-5, 143-6, 143-7,
    • 217-DS1, 217-DS2, 217-1, 217-2, 217-3, 217-4,
    • 353-DS1, 353-DS2, 353-1, 353-2, 353-7, 353-8,
    • 545-1, 545-2, 545-4,
    • 857-1, 857-2, 857-3, 857-4

Note for HFI these (and also the associated covariance matrices) are given in separate files named HFI_RIMO-Beams-nnnpc_Rm.nn.fits, where nnn is 100 or 075 and indicates the percentage (pc) of the sky included (see Masks and Beams sections).

For the LFI
  • the 3 LFI frequency channels (auto- products only), producing 3 extensions
    • 30, 44, 70
  • the 3 LFI 70GHz detector pairs (auto- products only), producing 3 extensions
    • 18-23, 19-22, 20-21

The extension names are of the form BEAMWF_U1XU2 where U1 and U2 are one (possibly the same) detection unit from one of the main groups above (i.e. there are no cross products between detsets and frequency channels, or between HFI and LFI). Each extension contains the columns:

NOMINAL (HFI, Real*4) 
the beam window function proper,
BL (LFI, Real*4) 
the beam window function proper,
EIGEN_n (Real*4, n=1-5 for the HFI, n=1-4 for the LFI)
the five/four corresponding error modes.

and the following keywords give further information, only for the HFI:

NMODES (Integer) 
the number of EIGEN_* modes,
LMIN and LMAX (Integer) 
the starting and ending (both included) multipoles of the vectors NOMINAL and EIGEN_*
LMIN_EM and LMAX_EM (Integer) 
that give the range of the valid samples of the EIGEN_* vectors. Here LMAX_EM is always less than or equal to LMAX. On the range LMAX_EM+1 to LMAX the values of EIGEN_* are set to NaN, while the values of NOMINAL only are a Gaussian extrapolation of the lower multipole window function, only provided for convenience.
CORRMAT (string) 
the name of the extension containing the corresponding beam correlation matrix

And finally see also the COMMENTs of each header for more specific details.

Beam Correlation Matrix

Two beam correlation matrices are given for the HFI, in two IMAGE extensions:

CORRBEAM_FREQ (Real*8) 
for the frequency channels (21 units), 105x015 pixel matrix,
CORRBEAM_DSET (Real*8) 
for the detsets (351 units), 1755x1755 pixel matrix

Each is a symmetric matrix with 1-valued diagonal, made of NBEAMS*NBEAMS blocks, each block being NMODES*NMODES in size. The n$^{th}$ row- (and column-) block entry relates to the B(l) model whose name is indicated in ROWn = BEAMWF_U1XU2 keywords, and the corresponding eigenmodes are stored in a HDU of the same name.

Each extension contains also the following keywords:

NDETS (Integer) 
the number of detector units
NBEAMS (Integer) 
the number of beams = NSETS * (NSETS+1) / 2
NMODES (Integer) 
here 5
L_PLUS (Integer) 
Eigenmode > 0 to break degeneracies
BLOCKn (string) 
for n=1-NBEAMS, gives the name of the extension containing the beam WF and error eigenmodes for the nth block

and some other ones for internal data checking and traceability

No beam correlation matrices are produced by the LFI by now. And for HFI these, together with the beam window functions, are given in a file separate from the main RIMO (see subsection above).

Appendices


The 2013 Instrument Model

Overview

The RIMO, or Reduced Instrument Model is a FITS file containing selected instrument characteristics that are needed by users who work with the released data products. It is described in detail in The HFI and LFI RIMO ICD (ref). There will be two RIMOs, one for each instrument, which will follow the same overall structure, but will differ in the details. The type of data in the RIMO can be:

Parameter 
namely scalars to give properties such as a noise level or a representative beam FWHM
Table 
to give, e.g., filter transmission profiles or noise power spectra
Image 
namely 2-D "flat" array, to give, e.g., the beam correlation matrices

The FITS file begins with primary header that contains some keywords that mainly for internal use and no data. The different types of data are written into different BINTABLE (for parameters and tables) or IMAGE (for 2-D arrays) extensions, as described below.

File Names

HFI
HFI_RIMO_R1.10.fits
LFI
LFI_RIMO_R1.12.fits


Map-level parameter data

The map-level data table contains the effective beam solid angle (total and out to different multiples of the beamFWHM) and noise information. It is written into a BINTABLE extension named MAP_PARAMS whose structure is different for HFI and LFI and is as follows. The noise description below is very simplified; a more accurate rendition can be obtained from the half-ring maps. Regarding the characterization of systematics, the user should use the survey differences.

HFI

FREQUENCY (String) 
a 3-digit string giving the reference frequency in GHz, i.e., of the form 217
OMEGA_F, OMEGA_F_ERR (Real*4) 
the full beam solid angle and its uncertainty, in armin2
OMEGA_1, OMEGA_1_DISP (Real*4) 
the beam solid angle out to 1FWHM, and its dispersion, in arcmin2
OMEGA_2, OMEGA_2_DISP (Real*4) 
the beam solid angle out to 2FWHM, and its dispersion, in arcmin2
FWHM (Real*4) 
FWHM of a Gaussian beam having the same (total) solid angle, in armin2. This is the best value for source flux determination
FWHMGAUS (Real*4) 
FWHM derived from best Gaussian fit to beam maps, in armin2. This is the best value for source identification
NOISE (Real*4) 
This is the typical noise/valid observation sample as derived from the high-l spectra of the half-ring maps, in the units of the corresponding map

For the Omega columns, the 'DISP' (for dispersion) column gives an estimate of the spatial variation as a function of position on the sky. This is the variation induced by combining the scanning beam determined from the planet observations with the scanning strategy, as described in Beams.

LFI

FREQUENCY (String) 
a 3-digit string giving the reference frequency in GHz, i.e., of the form 030, 044, 070
FWHM (Real*8) 
FWHM of a Gaussian beam having the same (total) solid angle, in arcmin
NOISE (Real*8) 
This is the average noise in T[math]\cdot[/math]s1/2
CENTRALFREQ (Real*4) 
This is the average central frequency in GHz
FWHM_EFF, FWHM_EFF_SIGMA (Real*4) 
This is the average FWHM of the effective beam, in arcmin, and its dispersion
ELLIPTICITY_EFF, ELLIPTICITY_EFF_SIGMA (Real*4) 
This is the average ellipticity and its dispersion
SOLID_ANGLE_EFF, SOLID_ANGLE_EFF_SIGMA (Real*4) 
This is the average full beam solid angle, in arcmin2, and its dispersion

Effective band transmission profiles

The effective filter bandpasses are given in different BINTABLE extensions. The extension is named BANDPASS_{name}, where name specified the frequency channel. In the case of the maps, the bandpasses are a weighted average of the bandpasses of the detectors that are used to build the map. For details see Planck-2013-IX[3]. The bandpasses are given as 4-column tables containing:

HFI

WAVENUMBER (Real*4) 
the wavenumber in cm-1, conversion to GHz is accomplished by multiplying by [math]10^{-7}c[/math] [mks].
TRANSMISSION (Real*4) 
the transmission (normalized to 1 at the max for HFI)
ERROR (Real*4) 
the statistical [math]1\sigma[/math] uncertainty for the transmission profile.
FLAG (Integer) 
a flag indicating if the data point is an independent frequency data point (nominally the case), or an FTS instrument line shape (ILS)-interpolated data point. The frequency data has been over-sampled by a factor of ~10 to assist in CO component separation efforts Planck-2013-XIII[5]Planck-2013-IX[3].

The number of rows will differ among the different extensions, but are the same, by construction, within each extension. Tables with the unit conversion coefficients and color correction factors for the HFI detectors (and LFI in some instances), including uncertainty estimates based on the uncertainty of the HFI detector spectral response are given in this appendix.

LFI

WAVENUMBER (Real*8) 
the wavenumber in GHz.
TRANSMISSION (Real*8) 
the transmission (normalized to have an integral of 1 for LFI)
UNCERTAINITY (Real*4) 
the statistical [math]1\sigma[/math] uncertainty for the transmission profile (not provided for LFI)
FLAG (Character) 
a flag, not used by now by the LFI

The number of rows will differ among the different extensions, but are the same, by construction, within each extension.


Beam Window Functions

Beam window functions and associated error descriptions are written into a BINTABLE for each detection unit, where detection unit consists of an auto or a cross product (for HFI only) of one (or two) frequency maps or detset maps used in the likelihood. Here they are:

For the HFI
  • the 6 HFI frequency channels, producing 21 extensions
    • 100, 143, 217, 353, 545, 857
  • 26 detsets, producing 351 extensions; the detsets used are, by frequency channel:
    • 100-DS1, 100-DS2,
    • 143-DS1, 143-DS2, 143-5, 143-6, 143-7,
    • 217-DS1, 217-DS2, 217-1, 217-2, 217-3, 217-4,
    • 353-DS1, 353-DS2, 353-1, 353-2, 353-7, 353-8,
    • 545-1, 545-2, 545-4,
    • 857-1, 857-2, 857-3, 857-4
For the LFI
  • the 3 LFI frequency channels, producing 3 extensions
    • 30, 44, 70


and the extension names are of the form BEAMWF_U1XU2 where U1 and U2 are one (possibly the same) detection unit from one of the main groups above (i.e. there are no cross products between detsets and frequency channels, or between HFI and LFI). Each extension contains the columns:

NOMINAL (Real*4) 
the beam window function proper,
EIGEN_n (Real*4, n=1-5 for the HFI, n=1-4 for the LFI)
the five/four corresponding error modes.

and the following keywords give further information, only for the HFI:

NMODES (Integer) 
the number of EIGEN_* modes,
LMIN and LMAX (Integer) 
the starting and ending (both included) multipoles of the vectors NOMINAL and EIGEN_*
LMIN_EM and LMAX_EM (Integer) 
that give the range of the valid samples of the EIGEN_* vectors. Here LMAX_EM is always less than or equal to LMAX. On the range LMAX_EM+1 to LMAX the values of EIGEN_* are set to NaN, while the values of NOMINAL only are a Gaussian extrapolation of the lower multipole window function, only provided for convenience.
CORRMAT (string) 
the name of the extension containing the corresponding beam correlation matrix

Beam Correlation Matrix

Two beam correlation matrices are given for the HFI, in two IMAGE extensions:

CORRBEAM_FREQ (Real*8) 
for the frequency channels (21 units), 105x015 pixel matrix,
CORRBEAM_DSET (Real*8) 
for the detsets (351 units), 1755x1755 pixel matrix

Each is a symmetric matrix with 1-valued diagonal, made of NBEAMS*NBEAMS blocks, each block being NMODES*NMODES in size. The n$^{th}$ row- (and column-) block entry relates to the B(l) model whose name is indicated in ROWn = BEAMWF_U1XU2 keywords, and the corresponding eigenmodes are stored in a HDU of the same name.

Each extension contains also the following keywords:

NDETS (Integer) 
the number of detector units
NBEAMS (Integer) 
the number of beams = NSETS * (NSETS+1) / 2
NMODES (Integer) 
here 5
L_PLUS (Integer) 
Eigenmode > 0 to break degeneracies
BLOCKn (string) 
for n=1-NBEAMS, gives the name of the extension containing the beam WF and error eigenmodes for the nth block

and some other ones for internal data checking and traceability

No beam correlation matrices are produced by the LFI by now.

Appendices


References[edit]

  1. ↑ 1.01.1 Planck 2015 results. II. LFI processing, Planck Collaboration, 2016, A&A, 594, A2.
  2. ↑ 2.02.1 Planck 2015 results. VII. High Frequency Instrument data processing: Time-ordered information and beam processing, Planck Collaboration, 2016, A&A, 594, A7.
  3. ↑ 3.03.13.23.33.43.5 Planck 2013 results. IX. HFI spectral response, Planck Collaboration, 2014, A&A, 571, A9.
  4. ↑ 4.04.1 Planck 2015 results. IV. LFI beams and window functions, Planck Collaboration, 2016, A&A, 594, A4.
  5. ↑ 5.05.15.2 Planck 2013 results. XIII. Galactic CO emission, Planck Collaboration, 2014, A&A, 571, A13.

reduced IMO

Flexible Image Transfer Specification

(Planck) High Frequency Instrument

(Planck) Low Frequency Instrument

Full-Width-at-Half-Maximum

Noise Equivalent Temperature

Cosmic Microwave background

random telegraphic signal

Instrument Line Shape

Interface Control Document

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