Ultraviolet Spectral Classification of O and B Stars in the Large Magellanic Cloud

1999 ◽  
Vol 117 (6) ◽  
pp. 2856-2867 ◽  
Author(s):  
Margaret M. Smith Neubig ◽  
Frederick C. Bruhweiler
1999 ◽  
Vol 118 (4) ◽  
pp. 1684-1699 ◽  
Author(s):  
Nolan R. Walborn ◽  
Laurent Drissen ◽  
Joel Wm. Parker ◽  
Abhijit Saha ◽  
John W. MacKenty ◽  
...  

1982 ◽  
Vol 255 ◽  
pp. 440 ◽  
Author(s):  
D. H. Clark ◽  
I. R. Tuohy ◽  
M. A. Dopita ◽  
D. S. Mathewson ◽  
K. S. Long ◽  
...  

1985 ◽  
Vol 111 ◽  
pp. 411-413
Author(s):  
Janet Rountree ◽  
George Sonneborn ◽  
Robert J. Panek

Previous studies of ultraviolet spectral classification have been insufficient to establish a comprehensive classification system for ultraviolet spectra of early-type stars because of inadequate spectral resolution. We have initiated a new study of ultraviolet spectral classification of B stars using high-dispersion IUE archival data. High-dispersion SWP spectra of MK standards and other B stars are retrieved from the IUE archives and numerically degraded to a uniform resolution of 0.25 or 0.50 Å. The spectra (in the form of plots or photowrites) are then visually examined with the aim of setting up a two-dimensional classification matrix. We follow the method used to create the MK classification system for visual spectra. The purpose of this work is to examine the applicability of the MK system (and in particular, the set of standard stars) in the ultraviolet, and to establish classification criteria in this spectral region.


2020 ◽  
Vol 499 (4) ◽  
pp. 5508-5526
Author(s):  
S K Sahoo ◽  
A S Baran ◽  
S Sanjayan ◽  
J Ostrowski

ABSTRACT We report the results of our search for pulsating subdwarf B stars in full frame images, sampled at 30 min cadence and collected during Year 1 of the TESS mission. Year 1 covers most of the southern ecliptic hemisphere. The sample of objects we checked for pulsations was selected from a subdwarf B stars data base available to public. Only two positive detections have been achieved, however, as a by-product of our search we found 1807 variable objects, most of them not classified, hence their specific variability class cannot be confirmed at this stage. Our preliminary discoveries include: 2 new subdwarf B (sdB) pulsators, 26 variables with known sdB spectra, 83 non-classified pulsating stars, 83 eclipsing binaries (detached and semidetached), a mix of 1535 pulsators and non-eclipsing binaries, two novae, and 77 variables with known (non-sdB) spectral classification. Among eclipsing binaries we identified two known HW Vir systems and four new candidates. The amplitude spectra of the two sdB pulsators are not rich in modes, but we derive estimates of the modal degree for one of them. In addition, we selected five sdBV candidates for mode identification among 83 pulsators and describe our results based on this preliminary analysis. Further progress will require spectral classification of the newly discovered variable stars, which hopefully include more subdwarf B stars.


1991 ◽  
Vol 369 ◽  
pp. 515 ◽  
Author(s):  
Janet Rountree ◽  
George Sonneborn

1997 ◽  
Vol 114 ◽  
pp. 1951 ◽  
Author(s):  
Margaret M. Smith Neubig ◽  
Frederick C. Bruhweiler

2001 ◽  
Vol 113 (787) ◽  
pp. 1130-1139 ◽  
Author(s):  
Elizabeth G. Jaxon ◽  
Martín A. Guerrero ◽  
J. Chris Howk ◽  
Nolan R. Walborn ◽  
You‐Hua Chu ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document