Andrea H. Prestwich

BVRI Light Curves for 22 Type 1a Supernovae

We present 1210 Johnson/Cousins B, V, R, and I photometric observations of 22 recent Type Ia supernovae (SNe Ia): SNe 1993ac, 1993ae, 1994M, 1994S, 1994T, 1994Q, 1994ae, 1995D, 1995E, 1995al, 1995ac, 1995ak, 1995bd, 1996C, 1996X, 1996Z, 1996ab, 1996ai, 1996bk, 1996bl, 1996bo, and 1996bv. Most of the photometry was obtained at the Fred Lawrence Whipple Observatory of the Harvard-Smithsonian Center for Astrophysics in a cooperative observing plan aimed at improving the database for SNe Ia. The redshifts of the sample range from cz = 1200 to 37,000 km s-1 with a mean of cz = 7000 km s-1.

Chandra High-Resolution Camera observations of the luminous X-ray source in the starburst galaxy M82

We have analyzed Chandra High Resolution Camera observations of the starburst galaxy M82, concentrating on the most luminous x-ray source. We find a position for the source of

Radio Emission from an Ultraluminous X-ray Source

\rm R.A. = 09^h 55^m 50^s.2, decl. = +69^{\circ} 40\arcmin 46\arcsec.7

The Effect of Starburst Metallicity on Bright X-ray Binary Formation Pathways

(J2000) with a

THE ORBITAL PERIOD OF THE WOLF-RAYET BINARY IC 10 X-1: DYNAMIC EVIDENCE THAT THE COMPACT OBJECT IS A BLACK HOLE

1\sigma

A Minisurvey of X-Ray Point Sources in Starburst and Nonstarburst Galaxies

radial error of

A CHANDRA HIGH-RESOLUTION X-RAY IMAGE OF CENTAURUS A

0.7\arcsec

CLASSIFYING X-RAY SOURCES IN EXTERNAL GALAXIES FROM X-RAY COLORS

. The accurate x-ray position shows that the luminous source is not at the dynamical centre of M82 nor coincident with any suggested radio AGN candidate. The source is highly variable between observations, which suggests that the source is a compact object and not a supernova or remnant. There is no significant short term variability within the observations. Dynamical friction and the off-center position place an upper bound of

X-ray binary formation in low-metallicity blue compact dwarf galaxies

10^{5} - 10^{6} M_{\odot}

A 33 hour period for the Wolf-Rayet/black hole X-ray binary candidate NGC 300 X-1

on the mass of the object, depending on its age. The x-ray luminosity suggests a compact object mass of at least