+--------------------------------------------------------+ | STScI Analysis Newsletter (STAN) | Cosmic Origins Spectrograph (COS) | Space Telescope Imaging Spectrograph (STIS) | June 2014 +--------------------------------------------------------+ In this Newsletter we provide some updates of interest to COS and STIS users who will be drafting and submitting Phase II HST programs over the next weeks Contents:
- Updated Extraction Heights in the COS ETC
- Gauging the impact of executing science program across
different COS/FUV lifetime positions lifetime positions - Time resolved observations with STIS/MAMA (TIME-TAG mode)
- Preliminary COS/FUV Pixel-to-Pixel flat field reference
file available
different COS/FUV lifetime positions lifetime positions It is expected that the position of COS FUV spectra will be relocated on the detector from the 2nd to the 3rd lifetime position early in 2015. There will some changes in instrument performance as a result of this move, and observers should evaluate if their science goals might be adversely affected should different observations in their program be split across the two lifetime positions. -------------------------------------------------------------- Time resolved observations with STIS/MAMA (TIME-TAG mode) The TIME-TAG mode records the arrival time of each photon on the COS and STIS MAMA detectors. The TIME-TAG mode is the default observation mode for COS but requires an active choice for the STIS users and is often overlooked. We encourage PIs of STIS/MAMA Cycle 22 programs to use the TIME-TAG mode for their observations of sources with count rates less than 20,000 counts/sec as it opens the time-domain window and further increases the legacy value of their observations at little or no extra cost. -------------------------------------------------------------- Preliminary COS/FUV Pixel-to-Pixel flat field reference
file available COS FUV spectra have multiple sources of fixed-patter noise, many of which are corrected in standard pipeline processing. Investigations are on-going to correct residual pixel-to-pixel variations, and while they are in-progress the COS team is making the preliminary calibration reference files available to all users, even if only high S/N observations will benefit from this calibration. +----------------------------------------------------------+ | Need help? http://www.stsci.edu/hst/stis/faqs/help +----------------------------------------------------------+ | To subscribe or unsubscribe to the STAN, send a message | to majordomo@stsci.edu with a blank subject line and | the following in the body: [un]subscribe cos_news | or [un]subscribe stis_news +----------------------------------------------------------+ | The Space Telescope Science Institute is operated by the | Association of Universities for Research in Astronomy, | Inc., under NASA contract NAS5-26555. +----------------------------------------------------------+