IR Standards: HZ43 Repeat

Details IR Standards: HZ43 Repeat IR Standards: HZ43 Repeat

Dec 1997

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1997hst..prop.8066b&link_type=abstract

HST Proposal ID #8066

Other

Hst Proposal Id #8066

Scientific paper

The purpose of the original IR Standards ID=7674 proposal is to establish a set of absolute flux standards on the WD scale that extend the existing wavelength coverage to 10200A with the STIS G750L grating setting. The final NICMOS calibration will be based on these results shortward of 10200A. The observations of HZ43 failed because the companion red star happened to be brighter in the F28X50LP acquistion filter, even though HZ43 is 4 times brighter in V and 35 times brighter in B. The acquistion for the repeat will be done in the blue 3729A F28x50OII filter. The observations of HZ43 are especially important because HZ43 is one of the 4 fundamental WD standard stars with pure hydrogen model atmospheres that define the WD flux scale {"White Dwarf Standard Stars: G191B2B, GD71, Gd153, HZ43", R. C. Bohlin, L. Colina, & D. S. Finley 1995, AJ, 110, 1316.} STIS observations of the other 3 fundamental standards show a difference in the region of the Paschen lines around 8500-10000 A, so that observations of the 4th star with G750L, plus 52X2 observations in G430L and G230LB, will help resolve the question of which star has the poorer flux model. The extra orbit {per visit} is to measure the throughput of apertures that are still poorly determined. HZ43 is an ideal source for these new aperture transmission measures, since exposure times are short and most of the target acquisition time can be saved. Discrepancies of up to 20% in the transmission throughput of the smaller apertures may be ascribed to poor pointing, to random expected scatter in the repeatability of the throughput, or even to a dependence on detector. Since few measurments exist, more data are needed, especially in G230LB, which has no data at all.

Affiliated with

Also associated with

No associations

Rating

IR Standards: HZ43 Repeat does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with IR Standards: HZ43 Repeat, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and IR Standards: HZ43 Repeat will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-896607