MBM 7 and MBM 55 X-ray sources Virtual Observatory Resource

Authors
  1. Hearty T.
  2. Magnani L.
  3. Caillault J.-P.
  4. Neuhaeuser R.
  5. Schmitt J.H.M.M.,Stauffer J.
  6. Published by
    CDS
Abstract

The star formation capability of two molecular clouds at high galactic latitude (|b|>30{deg}) is investigated. Possible pre-main sequence stars in and around the translucent clouds MBM7 and MBM55 have been identified via their X-ray emission by inspecting ROSAT All-Sky Survey observations of the clouds and environs and ROSAT pointed observations of the high-density cores within the clouds. Follow-up optical spectroscopy of the stellar X-ray sources with V<=15.5mag was conducted with the 1.5-m Fred Lawrence Whipple Observatory telescope to identify standard signatures of pre-main sequence stars (LiI {lambda}6708{AA} absorption and H{alpha} emission). We found 11 stars which have lithium equivalent widths, W(Li), above our detection threshold. Three of the stars with lithium also have weak H{alpha} emission. Relative ages for the stars with lithium are estimated by their position on an W(Li) vs. T_eff_ diagram. A calibration derived from data for several clusters with known ages indicates that the stars are older than the translucent high-latitude clouds. This conclusion is supported by a comparison with theoretical evolutionary tracks of the stars from our sample for which we have distance measurements from Hipparcos. We find it is unlikely that any of the X-ray active, lithium-rich stars we identified have formed in the clouds in question. Theoretical and observational arguments support this conclusion and render unlikely the possibility that low-extinction translucent clouds are the sites of star formation.

Keywords
  1. x-ray-sources
Bibliographic source Bibcode
1999A&A...341..163H
See also HTML
https://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/341/163
IVOA Identifier IVOID
ivo://CDS.VizieR/J/A+A/341/163
Document Object Identifer DOI
doi:10.26093/cds/vizier.33410163

Access

Web browser access HTML
https://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/341/163
https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/341/163
http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/341/163
IVOA Table Access TAP
https://tapvizier.cds.unistra.fr/TAPVizieR/tap
Run SQL-like queries with TAP-enabled clients (e.g., TOPCAT).
IVOA Cone Search SCS
For use with a cone search client (e.g., TOPCAT).
https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/341/163/table3?
https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/341/163/table3?
http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/341/163/table3?

History

1999-01-11T17:19:01Z
Resource record created
1999-01-11T16:19:25Z
Updated
1999-01-11T17:19:01Z
Created

Contact

Name
CDS support team
Postal Address
CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France
E-Mail
cds-question@unistra.fr