SREM

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Revision as of 17:26, 18 July 2012 by Lmendes (talk | contribs) (Data format)
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Design, performance and calibration documentation[edit]

Processed data[edit]

Description of the product[edit]

The SREM data files contain calibrated data for the different energy and particle species channels available in the SREM. Each data file contains 24 hours of data - from midnight to midnight (note this is not an OD) - with the date covered by the file easily identifiable through the file name.

Pipeline[edit]

TBW

Input Data[edit]

SREM calibrated data was produced from the SREM raw data acquired during the entire mission.

Related Products[edit]

Data for the SREM on board Herschel can be retrieved from the Herschel Science Archive.

SREM data from previous missions can be retrieved from the SREM archive at the Paul Scherrer Institut (PSI).

Data format[edit]

  • Naming convention
The files containing the SREM calibrated data will have a name of the form SREMPlanck_PACC_YYYYMMDD.fits where PACC stands for Processed ACCumulated data and YYYYMMDD is the date the data in the file was acquired.
  • Units
  • Format
Each file contains three binary table extensions named CDFFITS1,CDFFITS2 and CDFFITS3. The first extension contains the accumulated counts data, the second extension the labels to identify the data in the first extension and the third extension the total radiation dosis. The contents of each extension are as follows.
CDFFITS1
Column Name Contents Format Unit
EPOCH vector containing 1 string with UTC for accumulation period in ISO format (YYYY-MM-DDTHH:MM:SS.MMMZ) A24 NA
COUNTRATE vector containing 1 element for each channel (15 elements in total) with counts for accumulation period identified in the EPOCH column E15.4 [math]s^{-1}[/math]
ORBIT position of the SREM in the XXX frame E15.4 [math]K\!m[/math]
ATTITUDE TBW E15.4 [math]NA[/math]
PROT FITQUAL this is a another keyword I1 [math]NA[/math]
ODPF this is a another keyword E15.4 [math]H\!z[/math]
ODPFERR this is a another keyword E15.4 [math]H\!z[/math]
ELEC FITQUAL this is a another keyword I1 [math]H\!z[/math]
ODEF this is a another keyword [math]H\!z[/math]
ODEFERR this is a another keyword E15.4 [math]H\!z[/math]
ANISOTROPY this is a another keyword E15.4 [math]NA[/math]
TEMPERATURE 2 element vector containing temperature of the two detector heads at each EPOCH E15.4 [math]^\circ\!C[/math]


CDFFITS2
Column Name Contents Unit
EPOCH this is a keyword [math]K\!m^2[/math]


CDFFITS3
Column Name Contents Unit
RADEPOCH this is a keyword [math]K\!m^2[/math]
RADFET this is a another keyword [math]H\!z[/math]
  • N. Of Files
1500 (TBC)

Note: SREM calibrated data files where initially provided in the Common Data Format (cdf) format. This has traditionally been the preferred data format for SREM on board previous ESA missions. However, as cdf is not widely used in the astrophysics community it was later agreed with the provider that fits files should also be provided. This meant taking the original cdf format and converting it to fits. The original cdf files can be retrieved from the SREM site at the PSI.

Header keywords[edit]

For data provided in the form of fits files a table containing a description of all the header keywords should be included here. The table should follow this format

Keyword Name Description Unit
Keyword1 this is a keyword [math]K\!m^2[/math]
Keyword2 this is a another keyword [math]H\!z[/math]

Space Radiation Environment Monitor

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.

Universal Time Coordinate(d)

To be confirmed

European Space Agency