Astronomy and Astrophysics – Astrophysics
Scientific paper
Sep 1998
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1998a%26a...337..372r&link_type=abstract
Astronomy and Astrophysics, v.337, p.372-378 (1998)
Astronomy and Astrophysics
Astrophysics
14
Stars: Activity, X-Rays: Stars, Open Clusters And Associations: Individual: Ic 4756
Scientific paper
We have obtained an 88 kilosecond ROSAT HRI exposure of the intermediate-age open cluster IC 4756 with the purpose of detecting stars in the high luminosity tail (log L_X >= 10(29) erg s(-1) ) of its X-ray luminosity distribution. However, only 1 cluster member (HSS 201) out of the 60 members inside the central high-sensitivity region of the HRI field of view (FOV) was detected. This star has spectral type A8, suggesting a close binary system with a low mass X-ray emitting companion. We compare the distribution of upper limits for F and G-type dwarfs in IC 4756 with the X-ray distribution functions of the similarly aged Hyades and Praesepe clusters. The results of this statistical analysis are inconclusive for G-type stars, but suggest that at least F-type stars in IC 4756 are not as X-ray luminous as their Hyades counterparts, thus indicating intrinsic differences between the two clusters. Finally, our data indicate a deficit of very active binaries with respect to both Hyades and Praesepe, and older open clusters.
Drake Stephen Alan
Randich Sofia
Schmitt Juergen H. M. M.
Simon Theodore
Singh Kamal P.
No associations
LandOfFree
ROSAT HRI observations of the intermediate-age open cluster IC 4756 does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with ROSAT HRI observations of the intermediate-age open cluster IC 4756, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and ROSAT HRI observations of the intermediate-age open cluster IC 4756 will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-810055