Difference: SpireCalibrationWeb (94 vs. 95)

Revision 952013-10-09 - IvanV

Line: 1 to 1
 
META TOPICPARENT name="WebHome"

SPIRE instrument and calibration web pages

Line: 153 to 153
 
  • Faint (<10 Jy) and medium (<100 Jy) strength sources
  • Bright sources (>500 Jy)
Changed:
<
<
  • Extended sources
>
>
  • Semi-extended sources
  • Spectral mapping observations
 
  • Observations with few repetitions
Deleted:
<
<
  • H+L observations
  For faint sources, the subtraction of instrument, telescope and background emission is particularly important. Optimum subtraction can be performed in several ways (read the SPIRE Data Reduction Guide for details):
Line: 166 to 166
  A listing of the available Dark Sky observations can be found here.
Added:
>
>
 

Cookbooks

Cookbooks are provided inside the SPIRE Data Reduction Guide (see above).

Line: 231 to 234
 
    • These are also available in the SPIRE calibration context (photRsrf) and can be accessed in HIPE after a calibration context has been loaded (See above).

  • Neptune and Uranus models used for the SPIRE photometer flux calibration:
Changed:
<
<
    • The ESA2 models of the SPIRE calibration, used up to HIPE v10 and spire_cal_10_1, are available here.
    • NEW The ESA4 models of the SPIRE calibration, used from HIPE v11 and spire_cal_11_0, are available here.
>
>
    • The ESA2 models used up to HIPE v10 and spire_cal_10_1, are available here.
    • NEW The ESA4 models used from HIPE v11 and spire_cal_11_0, are available here.
 

Spectrometer calibration

Changed:
<
<
Important FTS information, including details of the calibration, point source and extended source calibration etc, is available in the SPIRE Observers' Manual, Sections 4.2 and 5.3. These two sections are a must-read for anybody processing SPIRE FTS data.
>
>
  • SPIRE Spectrometer Calibration:
    Full details of the SPIRE FTS calibration can be found in the SPIRE Observers Manual (to be updated soon) and in Swinyard et al. (2013, submitted).
    • Calibration uncertainties, which should be included in addition to the statistical errors of any measurement from HIPE v11 onwards, are as follows:
      • Point sources observed on the centre detectors (SSWD4 and SLWC3): the measured repeatability is 6%, with the following contributions: (i) absolute systematic uncertainty in the models from comparison of Uranus and Neptune - determined to be 3%; (i) the statistical repeatability determined from observations of Uranus and Neptune, with pointing corrected - estimated at 1% (excluding the edges of the bands); (iii) the uncertainties in the instrument and telescope model, which lead to an additive continuum offset error of 0.4 Jy for SLW and 0.3 Jy for SSW and (iv) the effect of the Herschel APE.
      • Sparse observations of significantly extended sources:
        • the absolute uncertainty in intensity for a reasonably bright, fully extended object, observed in the central detectors is, in theory, 1%, with the following contributions: (i) the systematic uncertainty in telescope model of 0.06%; (ii) the statistical repeatability estimated at 1% and (iii) an additive continuum offset of 3.4x10-20 W/m2/Hz/sr for SLW and 1.1x10-19 W/m2/Hz/sr for SSW.
        • In practice, truly extended sources tend to be faint and the uncertainty is therefore dominated by the additive offsets. When the source extent is larger than the main beam size, but not fully extended, or if there is structure inside the beam, then the uncertainties are dominated by the source-beam coupling (see Wu et al. 2013 ) and are significantly greater than 1%.
      • Mapping mode: the variations between detectors becomes important and the overall repeatability has been measured as 7% (see Benielli et al. 2013, submitted, for a full discussion of mapping mode observations). The off-axis detectors are less well calibrated, especially outside the unvignetted part of the field.

  • Uranus model used for the SPIRE FTS point-source flux calibration:
    • The ESA4 model, used from HIPE v10, is available here.
 

Interest groups and scripts

 
This site is powered by the TWiki collaboration platform Powered by Perl