Astron. Astrophys. Suppl. Ser.
Volume 145, Number 2, August 2000
|Page(s)||187 - 195|
|Published online||15 August 2000|
II. in Taurus-Auriga, Orion and Scorpius
Instituto de Astronomía, Carretera Tijuana Ensenada km 107, Ensenada B.C., CP. 22860, México
2 Osservatorio Astronomico di Capodimonte, Via Moiariello 16, I-80131 Napoli, Italy
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Accepted: 11 April 2000
We present uvby-β photometry of 116 X-ray flux-selected active stars in the directions of the Orion (40), Taurus-Auriga (58) and Scorpius OB2-2 (18) star forming regions. Additionally, we give near IR JHK photometry of 20 active stars in the Taurus-Auriga direction. The program stars were selected from the ROSAT All Sky Survey and EINSTEIN X-ray surveys and are spectroscopically confirmed weak-line T Tauri stars and weak-line T Tauri star candidates. The photometry confirms the young nature of the program stars and also indicates that a significant fraction of the sample could be foreground objects. The data given here probably represent the largest homogeneous uvby-β photometric sample of new WTTS and WTTS candidates. Many objects in the sample are observed photometrically for the first time.
Key words: stars: activity / stars: evolution / stars: pre-main sequence
Based on observations collected at the Observatorio Astronómico Nacional in Sierra San Pedro Mártir, Baja California, México.
Tables 1-4 are also available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (220.127.116.11) or via http://cdsweb.u-strasbg.fr/Abstract.html
© European Southern Observatory (ESO), 2000