|
Документ взят из кэша поисковой машины. Адрес
оригинального документа
: http://www.stsci.edu/ftp/instrument_news/GHRS/Ghrs_isr/ghrs_isr074/ghrs_isr074_5.html
Дата изменения: Fri May 31 02:17:34 1996 Дата индексирования: Sun Dec 23 21:07:37 2007 Кодировка: Поисковые слова: освещенность |
Purpose: The purpose of this program is to monitor the sensitivity, wavelength and detector calibrations of Side 1.
Description: Four times per year (twice in Cycle 6) the following observations will be done:
DETECTOR CALIBRATIONS
1) dark count measurement
2) focus check at nominal high voltage and tweak current
3) flat field exposure at center of photocathode
4) coarse sample mapping function at central y deflection
5) coarse line mapping function at central x deflection
SENSITIVITY MONITORING:
The sensitivity calibration of the GHRS Side 1 grating G140L will be monitored with the UV spectrophotometric standard star BD+28D4211.
WAVELENGTH MONITORING:
The spectral cal lamp mini-functional test for the first order gratings will be done. It is an internal test which makes measurements of the lamp (SC2). It is used to monitor the carrousel function, Y deflections, resolving power, and sensitivity. All observations are with the LSA or the SC2 aperture.
Fraction of GO Programs Supported: All GHRS programs using gratings G140M (10%) and G140L (27%) for wavelengths and sensitivities. The detector calibration part supports ECH-A (11%) in addition to G140L and G140M.
Resources:
Observation: Internal-14 orbits (7 orbits for each of the 2 executions. Note: the internal orbits are full orbits). External-2 orbits (1 orbit for each of the 2 executions).
Analysis: 0.24 FTE. The data will be reduced and analyzed by technical assistants, L. E. Sherbert (0.08 FTE) and A. Gonnella (0.08 FTE) under the supervision of an Instrument Scientist (0.04 FTE per execution for a total of 0.08 FTE).
Special Requirements: One complete set of observations (detector + sensitivity + wavelengths) should be on one SMS. The detector calibrations themselves should be executed within 24 hours. The repeat should occur should occur after 120 +/- 10 days.
Accuracy: Relative sensitivities will be measured to better than 2%. Wavelengths should be good to within 1 diode RMS.
Products: The results of the test will be discussed in an ISR to be published 2 months after completion of the program.