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Title: THE GALACTIC O-STAR SPECTROSCOPIC SURVEY. I. CLASSIFICATION SYSTEM AND BRIGHT NORTHERN STARS IN THE BLUE-VIOLET AT R {approx} 2500

Abstract

We present the first installment of a massive spectroscopic survey of Galactic O stars, based on new, high signal-to-noise ratio, R {approx} 2500 digital observations from both hemispheres selected from the Galactic O-Star Catalog of MaIz Apellaniz et al. and Sota et al. The spectral classification system is rediscussed and a new atlas is presented, which supersedes previous versions. Extensive sequences of exceptional objects are given, including types Ofc, ON/OC, Onfp, Of?p, Oe, and double-lined spectroscopic binaries. The remaining normal spectra bring this first sample to 184 stars, which is close to complete to B = 8 and north of {delta} = -20{sup 0} and includes all of the northern objects in MaIz Apellaniz et al. that are still classified as O stars. The systematic and random accuracies of these classifications are substantially higher than previously attainable, because of the quality, quantity, and homogeneity of the data and analysis procedures. These results will enhance subsequent investigations in Galactic astronomy and stellar astrophysics. In the future, we will publish the rest of the survey, beginning with a second paper that will include most of the southern stars in MaIz Apellaniz et al.

Authors:
; ;  [1];  [2];  [3];  [4];  [5];  [6]
  1. Instituto de Astrofisica de Andalucia-CSIC, Glorieta de la Astronomia s/n, 18008 Granada (Spain)
  2. Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States)
  3. Instituto de Ciencias Astronomicas, de la Tierra y del Espacio, Casilla 467, 5400 San Juan (Argentina)
  4. Las Campanas Observatory, Observatories of the Carnegie Institution of Washington, La Serena (Chile)
  5. Instituto de Astrofisica de La Plata (CCT La Plata-CONICET, Universidad Nacional de La Plata), Paseo del Bosque s/n, 1900 La Plata (Argentina)
  6. Departamento de Fisica, Universidad de La Serena, Av. Cisternas 1200 Norte, La Serena (Chile)
Publication Date:
OSTI Identifier:
21560410
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal, Supplement Series; Journal Volume: 193; Journal Issue: 2; Other Information: DOI: 10.1088/0067-0049/193/2/24
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ACCURACY; CATALOGS; CLASSIFICATION; SIGNAL-TO-NOISE RATIO; SPECTRA; STARS; DIMENSIONLESS NUMBERS; DOCUMENT TYPES

Citation Formats

Sota, A., Maiz Apellaniz, J., Alfaro, E. J., Walborn, N. R., Barba, R. H., Morrell, N. I., Gamen, R. C., and Arias, J. I., E-mail: jmaiz@iaa.es. THE GALACTIC O-STAR SPECTROSCOPIC SURVEY. I. CLASSIFICATION SYSTEM AND BRIGHT NORTHERN STARS IN THE BLUE-VIOLET AT R {approx} 2500. United States: N. p., 2011. Web. doi:10.1088/0067-0049/193/2/24.
Sota, A., Maiz Apellaniz, J., Alfaro, E. J., Walborn, N. R., Barba, R. H., Morrell, N. I., Gamen, R. C., & Arias, J. I., E-mail: jmaiz@iaa.es. THE GALACTIC O-STAR SPECTROSCOPIC SURVEY. I. CLASSIFICATION SYSTEM AND BRIGHT NORTHERN STARS IN THE BLUE-VIOLET AT R {approx} 2500. United States. doi:10.1088/0067-0049/193/2/24.
Sota, A., Maiz Apellaniz, J., Alfaro, E. J., Walborn, N. R., Barba, R. H., Morrell, N. I., Gamen, R. C., and Arias, J. I., E-mail: jmaiz@iaa.es. Fri . "THE GALACTIC O-STAR SPECTROSCOPIC SURVEY. I. CLASSIFICATION SYSTEM AND BRIGHT NORTHERN STARS IN THE BLUE-VIOLET AT R {approx} 2500". United States. doi:10.1088/0067-0049/193/2/24.
@article{osti_21560410,
title = {THE GALACTIC O-STAR SPECTROSCOPIC SURVEY. I. CLASSIFICATION SYSTEM AND BRIGHT NORTHERN STARS IN THE BLUE-VIOLET AT R {approx} 2500},
author = {Sota, A. and Maiz Apellaniz, J. and Alfaro, E. J. and Walborn, N. R. and Barba, R. H. and Morrell, N. I. and Gamen, R. C. and Arias, J. I., E-mail: jmaiz@iaa.es},
abstractNote = {We present the first installment of a massive spectroscopic survey of Galactic O stars, based on new, high signal-to-noise ratio, R {approx} 2500 digital observations from both hemispheres selected from the Galactic O-Star Catalog of MaIz Apellaniz et al. and Sota et al. The spectral classification system is rediscussed and a new atlas is presented, which supersedes previous versions. Extensive sequences of exceptional objects are given, including types Ofc, ON/OC, Onfp, Of?p, Oe, and double-lined spectroscopic binaries. The remaining normal spectra bring this first sample to 184 stars, which is close to complete to B = 8 and north of {delta} = -20{sup 0} and includes all of the northern objects in MaIz Apellaniz et al. that are still classified as O stars. The systematic and random accuracies of these classifications are substantially higher than previously attainable, because of the quality, quantity, and homogeneity of the data and analysis procedures. These results will enhance subsequent investigations in Galactic astronomy and stellar astrophysics. In the future, we will publish the rest of the survey, beginning with a second paper that will include most of the southern stars in MaIz Apellaniz et al.},
doi = {10.1088/0067-0049/193/2/24},
journal = {Astrophysical Journal, Supplement Series},
number = 2,
volume = 193,
place = {United States},
year = {Fri Apr 01 00:00:00 EDT 2011},
month = {Fri Apr 01 00:00:00 EDT 2011}
}
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