Difference between revisions of "Glossary"

From Planck PLA Wiki
Jump to: navigation, search
 
(20 intermediate revisions by 5 users not shown)
Line 1: Line 1:
[[Category:Appendix]]
+
* '''4K lines''': EMI/EMC influence of the 4K cooler mechanical motion on the bolometer readout electronics.
[[Category:PSOBook]]
+
* '''calibration''' [HFI meaning]: For a single detector, the absolute calibration is gain factor between the measured signal (watts absorbed by the detector) and the sky signal (in astrophysical units); can vary with time.  For  a set of detectors, the relative calibration is the difference in the calibration between detector pairs.  The latter can be measured very accurately from the observations of the same source by different detectors, and is only slightly affected by the differences in the detector spectral responses, which are similar; the former requires observations of sources with well modeled spectral energy distributions or well known spectra, and requires that the detector's spectral bandpass also be well known.
 
+
* '''calibration''': [LFI meaning]: absolute calibration refers to the 0th order calibration for each channel, 1 single number, while the relative calibration refers to the component of the calibration that varies pointing period by pointing period.
This page gives definition of some words commonly used in this Explanatory Supplement.
 
 
 
* '''ACMS''' : Attitude Control & Measurement Subsystem (AOCS)
 
* '''AHF''' : Attitude History File
 
* '''APID''' : Application Program Identifier
 
* '''APPL ''' : Augmented Preprogrammed Pointing List
 
* '''CDMS''' : Command and Data Management System
 
* '''CDMU''' : Command and Data Management Unit
 
* '''CMB''' : Cosmic Microwave background
 
* '''CoP''' : Commissioning Phase
 
* '''CTR''' : Central Time Reference
 
* '''CUC''' : CCSDS Unsegmented Time Code
 
* '''DCE''' : Dilution Cooler Electronics
 
* '''DDS''' : MOC's Data Distribution System
 
 
* '''detector set''' [HFI meaning]: a detector set (aka detset aka quad) is a combinaison of two pairs of Polarization Sensitive Bolometers pairs at the proper orientations. The lists of detsets is given in [[Frequency_Maps#Detector-set_maps | here]].
 
* '''detector set''' [HFI meaning]: a detector set (aka detset aka quad) is a combinaison of two pairs of Polarization Sensitive Bolometers pairs at the proper orientations. The lists of detsets is given in [[Frequency_Maps#Detector-set_maps | here]].
* '''DPC''' : Data Processing Center
+
* '''DMC''' : Data Management Component, the databases used at the HFI and LFI DPCs
* '''DPU''' : Data Processing Unit
 
* '''DQR ''' : Daily Quality Report
 
* '''DTCP''' : Daily Tele-Communication Period
 
 
* '''effective beam''' [HFI meaning]: the effective beam at the map level is the overall angular response to the sky in a map pixel, which results from the combined effect of the instrumental response, the scanning strategy and the data processing.
 
* '''effective beam''' [HFI meaning]: the effective beam at the map level is the overall angular response to the sky in a map pixel, which results from the combined effect of the instrumental response, the scanning strategy and the data processing.
* '''EOL''' : End Of Life
+
* '''far sidelobe''' [HFI meaning]: the response to the sky of a detector more than 5 degrees from the beam centroid.
* '''ERCSC''' : Early Release Compact Source Catalog
+
* '''half ring difference''' : difference between the map built using the first half of each pointing period (typically 20 minutes of  contiguous data) and the one built with the second half. This difference effectively removes the sky signal and most of the correlated noise, leaving only the noise components that have time scales of < ~ 20 min.
* '''ESA''' : European Space Agency
+
* '''HEALPix''': ([http://healpix.sourceforge.net Hierarchical Equal Area isoLatitude Pixelation of a sphere], {{BibCite|gorski2005}}) pixelation used to produce Planck sky maps (and HFI HPR).
* '''ESOC''' : European Space Operations Centre (Darmstadt)
+
* '''HPR''' [HFI meaning]: HEALPix Rings are introduced to avoid any additional binning of the data. We choose a sky pixelization as a basis for this ring making. HPR are therefore partial sky maps produced via a projection onto the sky of each single pointing period separately.
* '''ESTEC''' : European Space TEchnology and Research Centre
 
* '''FITS ''' : Flexible Image Transfer Specification
 
* '''focal plane geometry'''  [HFI meaning]
 
* '''FOG''' : Fiber Optic Gyroscope
 
* '''FOV''' : Field-Of-View
 
* '''FPU''' : Focal Plane Unit
 
* '''FWHM ''' : Full-Width-at-Half-Maximum
 
* '''HCM''' : Angular momentum Control Mode
 
* '''HEMT''' : High Electron Mobility Transistor
 
* '''HFI''' : High Frequency Instrument
 
* '''HPFTS''' : Herschel/Planck File Transfer System
 
* '''HPMCS''' : Herschel/Planck Mission Control System
 
* '''HPR''' [HFI meaning]: HEALPix Rings are introduced to avoid any additional binning of the data. We choose a sky pixelization as a basis for this ring making (HEALPix, Górski et al. 2005). HPR are therefore partial sky maps produced via a projection onto the sky of each single pointing period separately.
 
* '''HSK''' : House-Keeping data
 
* '''ICD''' : Interface Control Document
 
 
* '''IMO''' [HFI meaning]: the HFI Instrument MOdel is a central repository containing the models (or a link to them) and sets of fixed parameters used in these models describing for example how photons are gathered and transformed into data. IMO is oriented toward the data reduction and data processing. IMO is also used to monitor the instrument health. IMO represents at any time the official knowledge of the instrument response. It is intended to represent its best current knowledge agreed on by the project and applicable to the data processing. IMO does not represent the knowledge of the instrument. It is a knowledge of its response, (e.g. how photons are gathered and transformed into data). It is a simplified fraction of this knowledge directly useful to reduce the data. The IMO is restricted to the sole parameters used in the DPC. IMO does not contain timelines, nor maps, although it can provide links to calibration timelines (e.g. gain evolution) and calibration maps (e.g. beam maps). Models do not need to be unique (not a single model for a single process). Depending on the purpose for which they are used, they can be more or less sophisticated. (e.g. bolometer models, beam representations, very simplified for first assessment of pointing parameters, ...). IMO does not choose between them : it contains the parameters for each of them at the same time. See HFI RIMO.
 
* '''IMO''' [HFI meaning]: the HFI Instrument MOdel is a central repository containing the models (or a link to them) and sets of fixed parameters used in these models describing for example how photons are gathered and transformed into data. IMO is oriented toward the data reduction and data processing. IMO is also used to monitor the instrument health. IMO represents at any time the official knowledge of the instrument response. It is intended to represent its best current knowledge agreed on by the project and applicable to the data processing. IMO does not represent the knowledge of the instrument. It is a knowledge of its response, (e.g. how photons are gathered and transformed into data). It is a simplified fraction of this knowledge directly useful to reduce the data. The IMO is restricted to the sole parameters used in the DPC. IMO does not contain timelines, nor maps, although it can provide links to calibration timelines (e.g. gain evolution) and calibration maps (e.g. beam maps). Models do not need to be unique (not a single model for a single process). Depending on the purpose for which they are used, they can be more or less sophisticated. (e.g. bolometer models, beam representations, very simplified for first assessment of pointing parameters, ...). IMO does not choose between them : it contains the parameters for each of them at the same time. See HFI RIMO.
* '''IOT''' : Instrument Operation Team
+
* '''jump''' : sudden change of the baseline level inside a ring
* '''JFET''' : Junction Field Elect Transistor
+
* '''main beam''' [HFI meaning] Response to the sky within 23 arcminutes of the centroid of response.
* '''LEOP''' : Launch & Early Orbit Phase
+
* '''near sidelobe''' [HFI meaning] Response to the sky between 23 arcminutes and 5 degrees from the main beam centroid.
* '''LFI''' : (Planck) Low Frequency Instrument
 
* '''LOBT''' : Local On Board Time
 
* '''LOS''' : Line Of Sight
 
* '''mission''' [HFI meaning]
 
* '''MOC''' : [ESA's] Mission Operation Center [Darmstadt, Germany]
 
* '''NET ''' : Noise Equivalent Temperature
 
* '''OBT ''' : On-Board Time
 
 
* '''OD''' : Operation Day definition is geometric visibility driven as it runs from the start of a DTCP (satellite Acquisition Of Signal) to the start of the next DTCP. Given the different ground stations and spacecraft will takes which station for how long, the OD duration varies but it is basically once a day.
 
* '''OD''' : Operation Day definition is geometric visibility driven as it runs from the start of a DTCP (satellite Acquisition Of Signal) to the start of the next DTCP. Given the different ground stations and spacecraft will takes which station for how long, the OD duration varies but it is basically once a day.
* '''optical beam''' [HFI meaning]
+
* '''optical beam''' [HFI meaning] The response to the sky due to optics alone.
* '''P/L''' : Payload
 
* '''PAU''' : Pre_Amplification Unit
 
 
* '''PBR''' [HFI meaning]: Phase Bin Rings provide a compressed and higher signal-to-noise ratio rendition of the original Time Order Data
 
* '''PBR''' [HFI meaning]: Phase Bin Rings provide a compressed and higher signal-to-noise ratio rendition of the original Time Order Data
* '''PI''' : Principal Investigator
 
* '''PLA ''' : Planck Legacy Archive
 
* '''PLM''' : Payload Module
 
* '''POI''' : Phase-Ordered Information (DMC group/object)
 
 
* '''polarization leakage''' [HFI meaning]:  in general, systematic effects mix the I,Q,U signals. Given the amplitudes of the sky signals, leakage from temperature to polarisation can be dramatic for polarisation analysis.
 
* '''polarization leakage''' [HFI meaning]:  in general, systematic effects mix the I,Q,U signals. Given the amplitudes of the sky signals, leakage from temperature to polarisation can be dramatic for polarisation analysis.
* '''PPL ''' : Pre-programmed Pointing List
 
* '''PPLM''' : Planck Payload Module
 
* '''PSM ''' : Planck Sky Model
 
* '''PSO''' : Planck Science Office
 
* '''PUS''' : Packet Utilisation Standard
 
* '''RAF''' : Raw Attitude history File
 
* '''REBA''' : LFI Radiometer Electronics Box Assembly
 
* '''REU''' : Readout Electronic Unit
 
 
* '''ring''' [HFI meaning]: at the HFI DPC level the ring is the time intervalle between two First Thurster Firings as defined in {{ICD|AHF|link=AHF description document}}. It thus starts with a satellite slew and thus an unstable pointing period and continue with a satellite dwell and thus stable pointing period.
 
* '''ring''' [HFI meaning]: at the HFI DPC level the ring is the time intervalle between two First Thurster Firings as defined in {{ICD|AHF|link=AHF description document}}. It thus starts with a satellite slew and thus an unstable pointing period and continue with a satellite dwell and thus stable pointing period.
 
* '''RIMO''' [HFI meaning]: 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.
 
* '''RIMO''' [HFI meaning]: 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.
* '''ROI''' : Ring-Ordered Information (DMC group/object)
 
* '''rpm''' : revolutions per minute
 
* '''RSSD''' : Research Space Science Division of ESA [ESTEC, Netherlands]
 
* '''S/C''' : Spacecraft
 
* '''SAA''' : Solar Aspect Angle
 
 
* '''sample''' [HFI meaning]
 
* '''sample''' [HFI meaning]
 
* '''scanning beam''' [HFI meaning]: the scanning is defined as the beam measured from the response to a point source of the full optical and electronic system, after the filtering.
 
* '''scanning beam''' [HFI meaning]: the scanning is defined as the beam measured from the response to a point source of the full optical and electronic system, after the filtering.
* '''SCS''' : Sorption Cooler Subsystem (Planck)
+
* '''scanning beam''' [LFI meaning]: the actual  beam which couples the optics of the instrument with the scanning movement of the satellite (beam smearing). It can be measured from planet observations.
* '''SEV ''' : Sun Earth Vector
 
* '''SGR ''' : Small Gap Recovery
 
* '''SGS ''' : Science Ground Segment
 
* '''SIAM ''' : Spacecraft Instrument Alignment Matrix
 
 
* '''SOVT ''' : System Operation and Validation Test
 
* '''SOVT ''' : System Operation and Validation Test
* '''SPPT''' : Survey Performance and Planning Tool
+
* '''spectral response''' (or bandpass): steady state response of a detector system (i.e., detector and its electronics +  horn + filter) as a function of  frequency.  It does not consider the temporal response and associated transfer function.
* '''SREM''' : Space Radiation Environment Monitor
 
* '''SRP ''' : Solar Radiation Pressure
 
* '''SSCE''' : Sun-SpaceCraft-Earth angle max= 15°
 
* '''SSO''' : Solar System Object
 
* '''STR ''' : Star TRacker
 
 
* '''survey''' [HFI meaning]: sky surveys (aka Scan #)are defined in terms of the direction of the satellite's spin axis. Survey periods are given [[Frequency_Maps#Single_survey_maps | here]].
 
* '''survey''' [HFI meaning]: sky surveys (aka Scan #)are defined in terms of the direction of the satellite's spin axis. Survey periods are given [[Frequency_Maps#Single_survey_maps | here]].
* '''SVM''' : Service Module
+
* '''TOD ''' [HFI meaning]: Time-Ordered Data
* '''SZ ''' : Sunyaev-Zel'dovich effect
+
* '''TOD ''' [LFI meaning]: Time-Ordered Data, refers to calibrated data
* '''TBC''' : To Be Confirmed
+
* '''TOI''' [HFI meaning]: Time Ordered Information
* '''TBD''' : To Be Determined
+
* '''TOI''' [LFI meaning]: Time Ordered Information, refers to uncalibrated data
* '''TC''' : Tele-Command
 
* '''THF''' : Telecommand History File
 
* '''TOD ''' : Time-Ordered Data
 
* '''TOI''' : Time Ordered Information
 
* '''ToS''' : Time of Sample
 
* '''UTC''' : Universal Time Coordinate(d)
 
 
* '''warm units''' : JFET, Bellow, PAU et REU
 
* '''warm units''' : JFET, Bellow, PAU et REU
* '''WHR''' : Weekly Health Report
+
 
 +
= References =
 +
<References />
 +
 
 +
[[Category:Appendix|001]]
 +
[[Category:PSOBook]]

Latest revision as of 12:32, 28 August 2014

  • 4K lines: EMI/EMC influence of the 4K cooler mechanical motion on the bolometer readout electronics.
  • calibration [HFI meaning]: For a single detector, the absolute calibration is gain factor between the measured signal (watts absorbed by the detector) and the sky signal (in astrophysical units); can vary with time. For a set of detectors, the relative calibration is the difference in the calibration between detector pairs. The latter can be measured very accurately from the observations of the same source by different detectors, and is only slightly affected by the differences in the detector spectral responses, which are similar; the former requires observations of sources with well modeled spectral energy distributions or well known spectra, and requires that the detector's spectral bandpass also be well known.
  • calibration: [LFI meaning]: absolute calibration refers to the 0th order calibration for each channel, 1 single number, while the relative calibration refers to the component of the calibration that varies pointing period by pointing period.
  • detector set [HFI meaning]: a detector set (aka detset aka quad) is a combinaison of two pairs of Polarization Sensitive Bolometers pairs at the proper orientations. The lists of detsets is given in here.
  • DMC : Data Management Component, the databases used at the HFI and LFI DPCs
  • effective beam [HFI meaning]: the effective beam at the map level is the overall angular response to the sky in a map pixel, which results from the combined effect of the instrumental response, the scanning strategy and the data processing.
  • far sidelobe [HFI meaning]: the response to the sky of a detector more than 5 degrees from the beam centroid.
  • half ring difference : difference between the map built using the first half of each pointing period (typically 20 minutes of contiguous data) and the one built with the second half. This difference effectively removes the sky signal and most of the correlated noise, leaving only the noise components that have time scales of < ~ 20 min.
  • HEALPix: (Hierarchical Equal Area isoLatitude Pixelation of a sphere, [1]) pixelation used to produce Planck sky maps (and HFI HPR).
  • HPR [HFI meaning]: HEALPix Rings are introduced to avoid any additional binning of the data. We choose a sky pixelization as a basis for this ring making. HPR are therefore partial sky maps produced via a projection onto the sky of each single pointing period separately.
  • IMO [HFI meaning]: the HFI Instrument MOdel is a central repository containing the models (or a link to them) and sets of fixed parameters used in these models describing for example how photons are gathered and transformed into data. IMO is oriented toward the data reduction and data processing. IMO is also used to monitor the instrument health. IMO represents at any time the official knowledge of the instrument response. It is intended to represent its best current knowledge agreed on by the project and applicable to the data processing. IMO does not represent the knowledge of the instrument. It is a knowledge of its response, (e.g. how photons are gathered and transformed into data). It is a simplified fraction of this knowledge directly useful to reduce the data. The IMO is restricted to the sole parameters used in the DPC. IMO does not contain timelines, nor maps, although it can provide links to calibration timelines (e.g. gain evolution) and calibration maps (e.g. beam maps). Models do not need to be unique (not a single model for a single process). Depending on the purpose for which they are used, they can be more or less sophisticated. (e.g. bolometer models, beam representations, very simplified for first assessment of pointing parameters, ...). IMO does not choose between them : it contains the parameters for each of them at the same time. See HFI RIMO.
  • jump : sudden change of the baseline level inside a ring
  • main beam [HFI meaning] Response to the sky within 23 arcminutes of the centroid of response.
  • near sidelobe [HFI meaning] Response to the sky between 23 arcminutes and 5 degrees from the main beam centroid.
  • OD : Operation Day definition is geometric visibility driven as it runs from the start of a DTCP (satellite Acquisition Of Signal) to the start of the next DTCP. Given the different ground stations and spacecraft will takes which station for how long, the OD duration varies but it is basically once a day.
  • optical beam [HFI meaning] The response to the sky due to optics alone.
  • PBR [HFI meaning]: Phase Bin Rings provide a compressed and higher signal-to-noise ratio rendition of the original Time Order Data
  • polarization leakage [HFI meaning]: in general, systematic effects mix the I,Q,U signals. Given the amplitudes of the sky signals, leakage from temperature to polarisation can be dramatic for polarisation analysis.
  • ring [HFI meaning]: at the HFI DPC level the ring is the time intervalle between two First Thurster Firings as defined in AHF description document. It thus starts with a satellite slew and thus an unstable pointing period and continue with a satellite dwell and thus stable pointing period.
  • RIMO [HFI meaning]: 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.
  • sample [HFI meaning]
  • scanning beam [HFI meaning]: the scanning is defined as the beam measured from the response to a point source of the full optical and electronic system, after the filtering.
  • scanning beam [LFI meaning]: the actual beam which couples the optics of the instrument with the scanning movement of the satellite (beam smearing). It can be measured from planet observations.
  • SOVT  : System Operation and Validation Test
  • spectral response (or bandpass): steady state response of a detector system (i.e., detector and its electronics + horn + filter) as a function of frequency. It does not consider the temporal response and associated transfer function.
  • survey [HFI meaning]: sky surveys (aka Scan #)are defined in terms of the direction of the satellite's spin axis. Survey periods are given here.
  • TOD [HFI meaning]: Time-Ordered Data
  • TOD [LFI meaning]: Time-Ordered Data, refers to calibrated data
  • TOI [HFI meaning]: Time Ordered Information
  • TOI [LFI meaning]: Time Ordered Information, refers to uncalibrated data
  • warm units : JFET, Bellow, PAU et REU

References[edit]

  1. HEALPix: A Framework for High-Resolution Discretization and Fast Analysis of Data Distributed on the Sphere, K. M. Górski, E. Hivon, A. J. Banday, B. D. Wandelt, F. K. Hansen, M. Reinecke, M. Bartelmann, ApJ, 622, 759-771, (2005).

EMI/EMC influence of the 4K cooler mechanical motion on the bolometer readout electronics.

[LFI meaning]: absolute calibration refers to the 0th order calibration for each channel, 1 single number, while the relative calibration refers to the component of the calibration that varies pointing period by pointing period.

(Planck) High Frequency Instrument

(Planck) Low Frequency Instrument

Data Management Component, the databases used at the HFI and LFI DPCs

difference between the map built using the first half of each pointing period (typically 20 minutes of contiguous data) and the one built with the second half. This difference effectively removes the sky signal and most of the correlated noise, leaving only the noise components that have time scales of < ~ 20 min.

(Hierarchical Equal Area isoLatitude Pixelation of a sphere, <ref name="Template:Gorski2005">HEALPix: A Framework for High-Resolution Discretization and Fast Analysis of Data Distributed on the Sphere, K. M. Górski, E. Hivon, A. J. Banday, B. D. Wandelt, F. K. Hansen, M. Reinecke, M. Bartelmann, ApJ, 622, 759-771, (2005).

Data Processing Center

reduced IMO

sudden change of the baseline level inside a ring

Operation Day definition is geometric visibility driven as it runs from the start of a DTCP (satellite Acquisition Of Signal) to the start of the next DTCP. Given the different ground stations and spacecraft will takes which station for how long, the OD duration varies but it is basically once a day.

Daily Tele-Communication Period

Flexible Image Transfer Specification

System Operation and Validation Test

JFET, Bellow, PAU et REU

JFET, Bellow, PAU et REU

Junction Field Elect Transistor

Pre_Amplification Unit

Readout Electronic Unit