-------------+--------------------------------------------+--------------------- | FFFFFF OOOOOO SSS | STScI | FF OO OO SS | STAN - FOS Analysis | FFFF OO OO SS | Number 2 News | FF OO OO SS | November 1994 | FF OOOOOO SSS | -------------+--------------------------------------------+--------------------- CONTENTS: - FOS NEWS + FOS home page + Enhanced FOS flux calibration now available (CALFOS v. 2.0) + Calibration product review for the FOS (FOS - ISR 130) + FOS-assisted GHRS Acquisitions - CALIBRATION WORKSHOP May 15-17, 1995 - Appendix: FOS Contacts ================================================================================ FOS NEWS -------- FOS home page ------------- The FOS Instrument Scientists have produced an FOS home page which may be found within the Space Telescope Electronic Information Service, STEIS. You can reach this page from the "Instrument News" page, http://www.stsci.edu/ftp/instrument_news or directly at: http://www.stsci.edu/ftp/instrument_news/FOS/topfos.html From it one may access the latest FOS information, our Instrument Science Reports, the Instrument Handbook, etc. Please let us know how this may be improved. If you use Ghostview to examine the PostScript documents, they may be unreadable unless you zoom in to a Magstep value of 2. We are working to provide true html documents. Enhanced FOS flux calibration now available (CALFOS v. 2.0) ---------------- ------------------------------------------- Howard Bushouse FOS calibration programmer A new version of CALFOS is available. It includes several new flux calibration related routines that offer a significant improvement in the accuracy of the calibrated data. Observers who have existing pre-COSTAR FOS data are therefore encouraged to reprocess their data using CALFOS v2.0 in order to take advantage of the more accurate results. * NOTE: Due to the lack of a sufficient temporal baseline to provide * * the required post-COSTAR epoch calibration data, the new calibration * * methodology can only be applied to pre-COSTAR data at this time. * * New post-COSTAR calibration data will be forthcoming in the next several * * months. CALFOS V2.0 is backwards compatible with the old calibration * * routines and can be used to re-process post-COSTAR data. * The new routines include corrections for changes in aperture throughput as a function of OTA focus and corrections for changes in instrumental sensitivity as a function of time, the method by which the observed count rate data are converted to absolute fluxes has been modified. In the new calibration methods an average inverse sensitivity (AIS) curve is derived for only for the A-1 (4.3") aperture for each detector/grating combination. Data obtained through other apertures is first corrected for the differences in aperture throughput relative to the A-1, and is then multiplied by the AIS for the A-1 aperture to convert count rates to fluxes. FOS Instrument Science Report CAL/FOS-125 by D. Lindler and R. Bohlin details these modifications. An electronic version (without the figures) is available at: http://www.stsci.edu/ftp/instrument_news/FOS/pub/fos_isr125.txt Before you can reprocess old data with the new calibration steps it is necessary to add 8 new keywords to your existing raw (d0h) image headers. The task "addnewkeys" in the hst_calib.fos package will do this. More details about CALFOS V2.0 can be found in the publication CAL/FOS 129 by the author. A PostScript version is available at: http://www.stsci.edu/ftp/instrument_news/FOS/pub/fos_isr129.ps Paper copies of these documents can be requested from any of the contacts mentioned in the Appendix, to analysis@stsci.edu or by selecting the "ISR PAPER COPY" red button in the FOS ISR page: http://www.stsci.edu/ftp/instrument_news/FOS/fos_bib.html Until the next release of STSDAS, the code is available via anonymous ftp as a tar file in: ftp://ftp.stsci.edu/observer/temp/calfos_2p0.tar please download also the file: ftp://ftp.stsci.edu/observer/temp/README.calfos_2p0 Calibration product review for the FOS (FOS - ISR 130) ----------------------------------------------------- This Instrument Science Report includes a comprehensive review of the current status of each FOS calibration operation. A complete reference guide of all recommended Cycle 4 reference files and tables is provided as well. (A complete list of all Reference Files and Tables for pre- and post-COSTAR observations is also accessible via the FOS home page mentioned above or directly at http://www.stsci.edu/ftp/instrument_news/FOS/fos_refguide_access.html) ISR 130 also describes the recommended re-processing procedures for certain calibrations, notably flat field and flux calibrations, and also the processing errors affecting polarimetry and background subtraction. A PostScript version of this important ISR can be found at: http://www.stsci.edu/ftp/instrument_news/FOS/pub/fos_isr130.ps A paper copy can be requested from any the contacts mentioned in the Appendix, from analysis@stsci.edu or by selecting the "ISR PAPER COPY" red button in the FOS ISR page: http://www.stsci.edu/ftp/instrument_news/FOS/fos_bib.html FOS-Assisted Acquisitions for the GHRS -------------------------------------- David Soderblom Lead Instrument Scientist, GHRS Version 5 of the GHRS Instrument Handbook mentioned a new acquisition mode that we expected to have available in Cycle 5. In this mode an object too faint to acquire with Side 1 of the GHRS (because of the 12.75 maximum STEP-TIME) can be acquired with the FOS, followed by a blind offset to the GHRS LSA and an ACCUM with G140L (for example). A test was run of FOS-assisted acquisitions for the GHRS and it was successful. We expect to support such activities in Cycle 5. GHRS Instrument Science Report 68 describes the test and the results. You can request a copy from analysis@stsci.edu or any member of the Analysis Team listed in the Appendix. ================================================================================ CALIBRATION WORKSHOP -------------------- A workshop on calibrating HST data obtained after the servicing mission will be held at the Space Telescope Science Institute in Baltimore from May 15th to May 17th 1995. The topics will include reviews about: - Instrument performance and status - Changes in the calibration pipeline - Instrument specific information (break away groups) - Update on Pre-COSTAR calibrations - Access to old calibration information for archive users - Preview of new instruments - New data analysis tools In addition, contributed papers or posters are invited from all participants. If you are interested in participating, we request that you fill out the following questionnaire and return it by e-mail to etkins@stsci.edu. By doing so, you will be added to the mailing list and receive further announcements, the final program and detailed logistics information. ----------------------------8<-------------------------------------------------- Please keep me on your mailing list for the workshop CALIBRATING HUBBLE SPACE TELESCOPE: POST SERVICING MISSION in May 1995. Name: Institution: Address: Phone: Fax: e-mail: The likelihood for my attendance is (check one): > 75%: 25% - 75%: < 25%: I will probably want to give a presentation: Oral: Poster: Title if available: The break away groups that I plan on attending: WFPC2: FOC: FOS: GHRS: Please send this completed form to etkins@stsci.edu. Thank you ----------------------------8<-------------------------------------------------- ================================================================================ APPENDIX: FOS contacts ----------------------- Any questions about the scheduling of your observations should be addressed to your PRESTO contact. If you do not know who this person is, PRESTO's Mosaic page (http://presto.stsci.edu/public/propinfo.html) contains that information. Post-Observation questions should be addressed to the FOS Analysis Team, if your program is covered by this pilot project, or analysis@stsci.edu (410-338-1082). FOS Analysis Team: ------------------ Analysis Scientist: Jeffrey Hayes - hayes@stsci.edu - 410-338-4936 Analysis Specialist: Jennifer Christensen - christen@stsci.edu - 410-338-1265 Analysis Specialist: Stephan Martin - smartin@stsci.edu - 410-338-4724 http://www.stsci.edu/Ateam/ateam.html The FOS Instrument Scientists are: ---------------------------------- Michael Dahlem dahlem@stsci.edu 410-338-4733 Tony Keyes keyes@stsci.edu 410-338-4975 Anuradha Koratkar koratkar@stsci.edu 410-338-4470 http://www.stsci.edu/ftp/instrument_news/FOS/topfos.html ================================================================================ Comments, questions, requests for issues, additions or deletions to the mailing list, etc. can be e-mailed to analysis@stsci.edu ================================================================================ The Space Telescope Science Institute is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS5-26555. ================================================================================