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An XMM-Newton Search for X-Ray Emission from the Microlensing Event MACHO-96-BLG-5
MACHO-96-BLG-5 was a microlensing event observed toward the bulge of theGalaxy with an exceptionally long duration of ~970 days. Themicrolensing parallax fit parameters were used to estimate a lens massM=6+10-3 Msolar, corresponding to adistance d in the range 0.5-2 kpc. The upper limit on the absolutebrightness for main-sequence stars of the same mass is less than 1Lsolar, so the lens is a good black hole candidate. Such ablack hole would accrete from the interstellar medium, thereby emittingin the X-ray band. Here we report the analysis of a deep XMM-Newtonobservation toward the MACHO-96-BLG-5 lens position. Only an upper limit(99.8% confidence level) to the X-ray flux from the lens position,9.10×10-15 to 1.45×10-14 ergscm-2 s-1 in the 0.2-10 keV energy band, isobtained, allowing us to constrain the putative black hole's accretionparameters.
| The Tokyo PMC catalog 90-93: Catalog of positions of 6649 stars observed in 1990 through 1993 with Tokyo photoelectric meridian circle
The sixth annual catalog of the Tokyo Photoelectric Meridian Circle(PMC) is presented for 6649 stars which were observed at least two timesin January 1990 through March 1993. The mean positions of the starsobserved are given in the catalog at the corresponding mean epochs ofobservations of individual stars. The coordinates of the catalog arebased on the FK5 system, and referred to the equinox and equator ofJ2000.0. The mean local deviations of the observed positions from theFK5 catalog positions are constructed for the basic FK5 stars to comparewith those of the Tokyo PMC Catalog 89 and preliminary Hipparcos resultsof H30.
| Photometric observations of emission B-stars in the southern Milky Way
In order to study the distribution of Be stars and their correlation tothe local spiral structure of the Galaxy photoelectric UBV photometrywas carried out for a total of 488 Be stars located in the southernMilky Way between galactic longitudes 315 and 45 deg. UBV magnitudes arepresented for these stars.
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