Community Release Note for SPIRE Calibration 12_3
The SPIRE calibration tree "spire_cal_12_3" was released in May 2014 to be compatible with HIPE v12.1.
Note that this calibration tree updates the previously released calibration tree, 12_2.
Impact of the changes compared to the previous release (12_2)
- The RSRF product has been updated such that the frequency column is identical to the aperture efficiency products (correcting rounding effects). No change to actual RSRF numbers.
- The spectrometer bands are increased slightly in the overlap region and at the high frequency end of SSW:
- Old bands: SLW: 446.7-989.4 GHz; SSW: 959.3-1544.0 GHz
- New bands: SLW: 446.7-1018.0 GHz; SSW: 944.0-1568.0 GHz
- The extended calibration is not changed (apart from wider bands).
- The Low resolution point-source calibration is changed by <5% (before OD1000) and <2.7% (after OD1000) to bring it into line with the High resolution calibration. This was achieved by correcting for the pointing offset of Uranus during the calibration observations. The effect is to reduce the flux density of the final spectra. Changes are greatest for SSWD4 at high frequency, and smallest for SLWC3 (~1% for SLW).
- The High resolution point-source calibration has also been adjusted using improved corrections for the pointing offset of Uranus in the calibration observations. The effect for SSWD4 is ~2.5% before OD1000, and 0.8% after OD 1000. For SLWC3, the effect is <0.8% before OD1000 and <0.1% after OD1000. The effect is to increase the flux density in the final spectra.
- A small correction has been made to the point-source calibration for off-axis detectors for observations made before OD1000.
- The frequency grid for the beam profile shape been updated to match exactly that used in Makiwa et al. (2013, Applied Optics, 42, 3864) - this gives slightly better coverage at the edges of the new bands. The shapes themselves do not change.
Differences in individual products compared to the previous release
For detailed information about each product, see http://herschel.esac.esa.int/twiki/bin/view/Public/SpireCalibrationProducts.
- SCalPhotRsrf: Frequency column updated to match aperture efficiency product.
Release Date: May 2014 (coinciding with the public release of HIPE v12.1)
- SCalSpecInstRsrf: Wider bands
- SCalSpecTeleRsrf: Wider bands
- SCalSpecBeamParam: Wider bands + update corrections for pointing of Uranus observation used before and after OD1000.
- SCalSpecBandEdge: Wider bands
- SCalSpecBeamProf: Update frequency grid and store frequency scale in WCS 3rd axis (rather than separate array).