409 citations · 4k across the 58 of their papers we have counts for
7 papers · 1 filter
Photometric and Spectroscopic Analysis of Cool White Dwarfs with Trigonometric Parallax Measurements
P. Bergeron, S. K. Leggett, Maria Teresa Ruiz
A photometric and spectroscopic analysis of 152 cool white dwarf stars is presented. The discovery of 7 new DA white dwarfs, 2 new DQ white dwarfs, 1 new magnetic white dwarf, and…
The Luminosity Function of Magnitude and Proper-Motion Selected Samples. The case of White-Dwarfs
Rene A. Mendez, Maria T. Ruiz
The luminosity function of white dwarfs is a powerful tool for studies of the evolution and formation of the Milky Way. The (theoretical) white dwarf cooling sequence provides a us…
The interplay of observational errors through numerical simulations using the method for magnitude and proper-motion samples of local disk white dwarfs.}
Rene A. Mendez, Maria T. Ruiz
White dwarf cooling sequences provides a useful indicator of the evolutionary time scales involved in the chronometry and star formation history of the galactic disk and, for this…
PMN J1838-3427: A new gravitationally lensed quasar
Joshua N. Winn, Jacqueline N. Hewitt, Paul L. Schechter +11
We report the discovery of a new double-image quasar that was found during a search for gravitational lenses in the southern sky. Radio source PMN J1838-3427 is composed of two fla…
The Chemical Composition of the Small Magellanic Cloud H II Region NGC 346 and the Primordial Helium Abundance
Manuel Peimbert, Antonio Peimbert, Maria Teresa Ruiz
Spectrophotometry in the 3400-7400 range is presented for 13 areas of the brightest H II region in the SMC: NGC 346. The observations were obtained at CTIO with the 4-m telescope.…
A Near Infrared Polarized Bipolar Cone in the CIRCINUS Galaxy
M. Ruiz, D. M. Alexander, S. Young +3
We present near-infrared broad-band polarization images of the nuclear regions of the Circinus galaxy in the J, H and K bands. For the first time the south-eastern reflection cone…