NOAO >   Observing Info >   Approved Programs >   2018A-0051

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Program Information for 2018A-0051


PI: Saul J Adelman, The Citadel, adelmans@citadel.edu
Address: Physics Department, 171 Moultrie Street, Charleston, South Carolina 29409 United States of America

CoI: Austin F Gulliver, Brandon U.
CoI: Graham Hill, retired

Title: Spectral Synthesis High S/N Studies of Sharp-lined B, A, and F Stars Observed by STIS

Abstract: We propose to obtain very high quality optical region spectra of the remaining sharp-lined stars that we observed for our accepted STIS proposal "Advanced Spectral Library II: Hot Stars" to perform the highest quality analyses now possible of the observed optical and uv spectral regions. The spectra of these objects will be an important part of the scientific legacy of the Hubble Space Telescope. Although we have the analysis tools to do these studies ourselves, we expect to work with many of our STIS collaborators as was done for Sirius (Cowley et al. 2016). Collectively we will utilize the extensive experience of astronomical and laboratory spectroscopists for this project. These analyses should be exemplars for many years. We recognize that obtaining S/N 500+ spectra is somewhat unusual, but the spectral atlases we are producing should be the type of material that will be used for many years into the future. We are now working on the middle B and early A stars and then will proceed to the other three stars with spectral types near B1. We will use data from our forthcoming ASTRA Spectrophotometric Telescope. This should primarily yield improved effective temperatures and secondarily surface gravities. We need high S/N (500+) optical observations of these sharp-lined stars to perform state of-the-art spectrum synthesis calculations which will better account for line blending and illustrate problems with our knowledge of important atomic data. The later will be of interest to atomic spectroscopists. With those stars with similar effective temperatures and surface gravities we can study whether adjustments in the gf values can minimize the scatter about the mean.

Program Type: Standard/Galactic

Scheduled Nights:
Run 1 (2018A):  CT-1.5m-SVC/CHIRON -- 10hrs
Run 2 (2018A):  CT-1.5m-SVC/CHIRON -- 7hrs


National Optical Astronomy Observatory, 950 North Cherry Avenue, P.O. Box 26732, Tucson, Arizona 85726, Phone: (520) 318-8000, Fax: (520) 318-8360



NOAO >   Observing Info >   Approved Programs >   2018A-0051

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