Difference: SpireCalibrationWeb (89 vs. 90)

Revision 902013-06-20 - IvanV

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META TOPICPARENT name="WebHome"

SPIRE instrument and calibration web pages

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Software and documentation

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    • Warning, important Please note that there was a bug in the destriper task included in HIPE 9.0 that may affect your final map, especially if there are bright objects in the observed field. This has been corrected since HIPE 9.1. If your observation falls in the mentioned category, you are strongly advised to update your HIPE installation.

  • We also provide access to the latest stable developer build (latest stable CIB).
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    • Beware These developer builds do not undergo the same in-depth testing as the user releases do. The latest developer build can be found here.
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    • Beware These developer builds do not undergo the same in-depth testing as the user releases do. The latest developer build can be found here.
      Info Please contact the Herschel helpdesk if you plan to use a developer build as there may be some additional information needed in order for you to properly make use of it.
 
  • Within HIPE you can access all the SPIRE data reduction and HIPE-user documentation. The SPIRE Data Reduction Guide (SDRG) follows the user pipeline scripts and also explains the details of pipeline processing and data analysis. It is also available online here:
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 The best source of information for reducing SPIRE Photometer data is the SPIRE Data Reduction Guide available through the HIPE help. This runs through the User Pipeline scripts step by step, describes several other Useful Scripts, and offers advice for specific issues that might be encountered.

New definition of Leve2 products
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  • For versions of the HCSS prior to HIPE 10.0, a single point source calibrated (Jy/beam) map was provided in the Level 2 product for each of the PSW, PMW, PLW bands. However, for observations processed with HIPE 10.0 or later, more than one map calibration is made available within the Level 2 product. Maps are provided for the following scenarios for post HIPE 10.0 processing:
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  • For versions of the HCSS prior to HIPE 10.0, a single point source calibrated (Jy/beam) map was provided in the Level 2 product for each of the PSW, PMW, PLW bands. However, for observations processed with HIPE 10.0 or later, more than one map calibration is made available within the Level 2 product. Maps are provided for the following scenarios for post HIPE v10.0 processing:
 

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Planck-HFI & Herschel-SPIRE cross calibration: absolute offset re-processing

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Herschel-SPIRE detectors are only sensitive to relative variations, as a consequence the absolute brightness of the observed region is unknown and maps are constructed such that they have zero median. Planck-HFI detectors are similar to the SPIRE ones, however its observing strategy allows it to (almost) observe a sky's great circle every minute (having a 1 rpm spinning rate). By comparing the sky brightness as measured by COBE-FIRAS at the galactic poles (where the dust emission is lower), HFI is capable of setting an absolute offset to its maps. SPIRE and HFI share two channels with overlapping wavebands: SPIRE-PMW and HFI-857 have a similar filter profile, while SPIRE-PLW and HFI-545 are shifted by $\sim 10$\%.
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Herschel-SPIRE detectors are only sensitive to relative variations, as a consequence the absolute brightness of the observed region is unknown and maps are constructed such that they have zero median. Planck-HFI detectors are similar to the SPIRE ones, however its observing strategy allows it to (almost) observe a sky's great circle every minute (having a 1 rpm spinning rate). By comparing the sky brightness as measured by COBE-FIRAS at the galactic poles (where the dust emission is lower), HFI is capable of setting an absolute offset to its maps. SPIRE and HFI share two channels with overlapping wavebands: SPIRE-PMW and HFI-857 have a similar filter profile, while SPIRE-PLW and HFI-545 are shifted by ~10%.
  As of HCSS 10, a new task named zeroPointCorrection is available: this task calculates the absolute offset for a SPIRE map based on cross-calibration with HFI-545 and HFI-857 maps, colour-correcting HFI to SPIRE wavebands assuming a grey body function with fixed beta. At first, Planck data needed by the task were delivered to HSC under special agreement: as a consequence, Herschel users were not able to re-process the absolute offset calculation. However, Planck data became public in April 2013 and it is now possible to exectue the zeroPointCorrection.
 
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