+----------------------------------------------------------+ | NICMOS | STScI Analysis Newsletter | NICMOS STAN | December 2002 +----------------------------------------------------------+ Visit the NICMOS web site http://www.stsci.edu/hst/nicmos/ "New in the Last 45 Days" for all new information about NICMOS. CONTENTS (Optional): - HST Cycle 12 Call for Proposals - New NICMOS Instrument Handbook - NICMOS Coronagraphy White Paper - High S/N NICMOS Grism Capability - post-NCS NICMOS Linearity Calibration - post-NCS NICMOS Cold Mask Movement - post-NCS Darks - Cryocooler Status - post-NCS NICMOS Focus and Pointing - NICMOS preprints +----------------------------------------------------------+ http://www.stsci.edu/spd/cycle12/announce.html HST Cycle 12 Call for Proposals NASA and The Space Telescope Science Institute (STScI) are pleased to announce the Cycle 12 Call for Proposals for Hubble Space Telescope (HST) Observations and funding for Archival Research and Theoretical Research programs. Participation in this program is open to all categories of organizations, both domestic and foreign, including educational institutions, profit and nonprofit organizations, NASA Centers, and other Government agencies. This solicitation will be open from October 16, 2002 through January 24, 2003 8:00pm EST, and proposals may be submitted throughout this period. Results of the selection will be announced in April 2003. +----------------------------------------------------------+ http://www.stsci.edu/hst/nicmos/ New NICMOS Instrument Handbook The post-NCS updated NICMOS Instrument Handbook for Cycle 12 has been completed and released. The new Instrument Handbook is available on the NICMOS home web page. +----------------------------------------------------------+ http://www.stsci.edu/hst/nicmos/ NICMOS Coronagraphy White Paper A report comparing ground-based Adaptive Optics (AO) observations with HST/NICMOS direct imaging and coronagraphy has been prepared and released to STScI by Glenn Schneider, Steward Observatory, University of Arizona, Tucson, AZ. The report, title: "DOMAINS OF OBSERVABILTY IN THE NEAR-INFRARED with HST/NICMOS and (ADAPTIVE OPTICS AUGMENTED) LARGE GROUND-BASED TELESCOPES," is available on the HST Cycle 12 Phase I web page and on the NICMOS home web page. +----------------------------------------------------------+ http://www.stsci.edu/hst/nicmos/ High S/N NICMOS Grism Capability Results from a NICMOS calibration program to characterize the high S/N capability of NICMOS grism spectroscopy has been prepared and released. Instrument Science Report (ISR) ISR-NIC-2003-001, title: "High Signal-to-Noise, Differential NICMOS Spectrophotometry," is available on the NICMOS home web page. +----------------------------------------------------------+ http://www.stsci.edu/hst/nicmos/calibration/ post-NCS NICMOS Linearity Calibration ------------------------------------- Analysis of post-NCS long exposure images indicates that the linearity of the NICMOS detectors has not changed with the qualifier that the saturation limit is now lower. The current linearity files delivered to CDBS for use by the OPUS pipeline and calnica contain the pre-NCS correction coefficients, but decreased saturation values [node2]. These files are also available for NICMOS users on the NICMOS web page. New linearity reference files will be produced using the post-NCS data and installed in CDBS in the near future. post-NCS NICMOS Cold Mask Movement ---------------------------------- Deep PSF images of calibration target LHS1846 (J=8.65; J-K=0.75; sp.typ=M4V) were obtained in each NICMOS Camera (program ID: 9704). Analysis using phase retrieval software show no appreciable change in cold mask position since January 1999. post-NCS Darks -------------- The NICMOS "dark current" is composed of three independent components - a true dark-current which accumulates linearly with exposure time, an "amplifier glow" which results from operation of the four readout amplifiers near the detector corners, injecting a spatially dependent signal each time the detector is read out, and finally an amplifier-induced, spatially varying bias component called "shading," whose amplitude across the detector depends on the time since the non-destructive readout. All components of the darks have been characterized at the post-NCS operating temp of 77.1~K. The observed changes in characteristics were generally as-expected, based on data taken through this temperature range during the end-of-life (EOL) warmup in early 1999. The linear component of the dark current shows an increased amplitude and a large number of "hot" pixels across all the detectors. These pixels are still functional and calibratable, but have a much higher level of linear dark current than the mean of the rest of the array, giving an uncalibrated image a "salty" appearance. Small differences were seen in the amplifier glow component, but in general the amplitude and spatial extent of the glow are similar to the pre-NCS era. The shading components also showed small differences from the modeled values of EOL. New models were fit to the shading at the 77.1~K operating temperature. New reference files for the fixed temperature of 77.1~K have been built and installed into the calibration database. Cryocooler Status ----------------- The cryocooler has held the NICMOS detector temperatures quite well at ~77.1 K. The amplitude of daily variations of the detector temperatures is 0.05 K and larger deviations occur when HST is oriented to unusually cold or hot attitudes for extended periods of time. Furthermore, a slow seasonal increase of the detector temperatures to an average value of 77.19 K has occurred as the aft-shroud warmed with the approach of Earth to perihelion. An adjustment to decrease the NCC temperature control-law set-point by 0.05 K was performed on December 19, 2002 (day 2002.353 at 14:28:47 UT), which reduced the detector temperatures by 0.04 K on average. It is anticipated that a corresponding increase in the control-law set-point temperature will be required during Spring 2003 once Earth recedes from the Sun. +----------------------------------------------------------+ http://www.stsci.edu/hst/nicmos/performance/focus/ post-ncs_focus_update.html post-NCS NICMOS Focus and Pointing Monthly monitoring of the NICMOS focus will continue through February 2003 and bi-monthly there after. The latest focus results show that the focus is as expected and stable. Trending indicates the focus oscillates about the set values for each camera. The HST Secondary mirror was moved on December 2, 2002 (day 2002.336 at 21:00 UTC) to correct the HST focus. The movement of the mirror completed with no problems. The NICMOS focus monitor executed two days after the mirror movement and the results were nominal. The NICMOS science aperture file was updated and will take affect starting with observations on January 13, 2003. This is a result of the calibration program following the reactivation of NICMOS. Any data since the refurbishment that is retrieved from the HST Archive will automatically be recalibrated by OTFR with the new pointing values. +----------------------------------------------------------+ +----------------------------------------------------------+ | Additional general section(s) (e.g. NICMOS preprints) +----------------------------------------------------------+ http://www.stsci.edu/hst/nicmos/ Gilliland, R.L. and Arribas, S. 2003, "High Signal-to-Noise, Differential NICMOS Spectrophotometry," ISR-NIC-2003-001. King, N.L., Nota, A., Walsh, J.R., Panagia, N., Gull, T.R., Pasquali, A., Clampin, M., and Bergeron, L.E. 2002, "A Hubble Space Telescope Polarization Study of Dust in the eta Carinae Homunculus," ApJ, 581, 285. Noriega-Crespo, A., Cotera, A., Young, E., and Chen, H. 2002, "Hubble Space Telescope NICMOS Images of the HH 7/11 Outflow in NGC 1333," ApJ, 580, 959. Schneider, G. 2002, "Domains of Observabilty in the Near- Infrared with HST/NICMOS and (Adaptive Optics Augmented) Large Ground-Based Telescope," STScI White Paper. +----------------------------------------------------------+ | Help: http://www.stsci.edu/hst/nicmos/proposing/phase1 +----------------------------------------------------------+ | To subscribe or unsubscribe to the STAN, send a message | to majordomo@stsci.edu with the subject line blank and | the following in the body: [un]subscribe SINAME_news +----------------------------------------------------------+ | The Space Telescope Science Institute is operated by the | Association of Universities for Research in Astronomy, | Inc., under NASA contract NAS5-26555. +----------------------------------------------------------+
