Issue |
A&A
Volume 503, Number 3, September I 2009
|
|
---|---|---|
Page(s) | 1023 - 1036 | |
Section | Catalogs and data | |
DOI | https://doi.org/10.1051/0004-6361/200810798 | |
Published online | 09 July 2009 |
A variability sample catalogue selected from the Sydney Observatory Galactic Survey*
1
Observatoire astronomique, UMR 7550, 11 rue de l'Université, 67000 Strasbourg, France e-mail: fresneau@astro.u-strasbg.fr
2
Department of Physics, Central Michigan University, Mt. Pleasant, MI 48859, USA e-mail: osbor1wh@cmich.edu
Received:
13
August
2008
Accepted:
1
July
2009
Context. A set of stars brighter than about B-magnitude 14
and having at least three observations are identified in the Sydney
Observatory Galactic Survey, carried out over the years 1892–1932
along the galactic equator section
with galactic latitude
. Short-term (30 min) and
long-term (decades) magnitude variations in the data set
are analyzed.
Aims. Evidence is sought for a correlation between short-term and long-term variabilities which would identify stars in a non-quiescent phase.
Methods. We use a reduced proper motion diagram to classify the stars in
our sample into probable dwarfs, giants and other types. The validity of the
kinematical classification is checked using objective-prism spectroscopic
classification for early-type stars. A search is
made for statistical correlations between our variability indicators and
physical and kinematical stellar properties.
Results. We find that suspected photospheric activity for giant and dwarf stellar candidates is correlated with the time to cross the galactic thin disk. We estimate a significant apparent B-magnitude variation of ±0.25 over the 40 years of photographic observations, and candidates for monitoring for possible photospheric activity at the present time are selected employing a statistical colour-diagram which uses the total proper motion component as a distance indicator.
Conclusions. Follow up studies of our tentative findings are suggested.
Toward this aim the derived data for the set of stars
with variability information is archived as the variability Sample
Catalogue. The data for a set of
stars along
the section of the galactic equator
,
, and a set of of
stars
along the section of the galactic meridian
,
is also archived as a quick-look
facility for seeking long-term magnitude changes since the
century-old photographic observations were obtained.
Key words: surveys / stars: variables: general
© ESO, 2009
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.