NO NEUTRON STAR COMPANION TO THE LOWEST MASS SDSS WHITE DWARF
- Columbia Astrophysics Laboratory, Columbia University, New York, NY 10027 (United States)
- Department of Physics, University of Alberta, Edmonton, AB T6G 2G7 (Canada)
- Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States)
- Department of Astronomy, University of Washington, Seattle, WA 98195 (United States)
- Arecibo Observatory, Arecibo, PR 00612 (United States)
- Gemini Observatory, Northern Operations Center, Hilo, HI 96720 (United States)
SDSS J091709.55+463821.8 (hereafter J0917+4638) is the lowest surface gravity white dwarf (WD) currently known, with log g = 5.55 {+-} 0.05 (M {approx} 0.17 M{sub sun}). Such low-mass white dwarfs (LMWDs) are believed to originate in binaries that evolve into WD/WD or WD/neutron star (NS) systems. An optical search for J0917+4638's companion showed that it must be a compact object with a mass {>=}0.28 M{sub sun}. Here we report on Green Bank Telescope 820 MHz and XMM-Newton X-ray observations of J0917+4638 intended to uncover a potential NS companion to the LMWD. No convincing pulsar signal is detected in our radio data. Our X-ray observation also failed to detect X-ray emission from J0917+4638's companion, while we would have detected any of the millisecond radio pulsars in 47 Tuc. We conclude that the companion is almost certainly another WD.
- OSTI ID:
- 21313794
- Journal Information:
- Astrophysical Journal (Online), Vol. 700, Issue 2; Other Information: DOI: 10.1088/0004-637X/700/2/L123; Country of input: International Atomic Energy Agency (IAEA); ISSN 1538-4357
- Country of Publication:
- United States
- Language:
- English
Similar Records
A Multiwavelength Study of Nearby Millisecond Pulsar PSR J1400−1431: Improved Astrometry and an Optical Detection of Its Cool White Dwarf Companion
An eccentric binary millisecond pulsar with a helium white dwarf companion in the galactic field