Related papers: A Massive White Dwarf Companion to the Eccentric B…
Most millisecond pulsars with low-mass companions are in systems with either helium-core white dwarfs or non-degenerate ("black widow" or "redback") stars. A candidate counterpart to PSR J1816+4510 was identified by Kaplan et al. (2012)…
We report on Keck and {\em Hubble Space Telescope} observations of the binary millisecond pulsar PSR B1855+09. We detect its white-dwarf companion and measure $\mv=25.90\pm0.12$ and $\mi=24.19\pm0.11$ (Vega system). From the…
We report the optical discovery of the companion to the 2 M_sun millisecond pulsar PSR J1614-2230. The optical colors show that the 0.5 M_sun companion is a 2.2 Gyr old He-CO white dwarf. We infer that $\dot{M}$ during the accretion phase…
We present observations of fields containing eight recently discovered binary millisecond pulsars using the telescopes at MDM Observatory. Optical counterparts to four of these systems are detected, one of which, PSR J2214+3000, is a novel…
We report on a search for pulsars at the positions of eight low-mass white dwarfs and one higher-mass white dwarf with the 100-m Effelsberg Radio Telescope. These systems have orbital parameters suggesting that their unseen companions are…
We report on Keck optical BVRI images and spectroscopy of the companion of the binary millisecond pulsar PSR J0218+4232. A faint bluish (V=24.2, B-V=0.25) counterpart is observed at the pulsar location. Spectra of this counterpart reveal…
We report detection of the binary companion to the millisecond pulsar J2302+4442 based on the deep observations performed with the Gran Telescopio Canarias. The observations revealed an optical source with $r'$ = 23.33$\pm$0.02 and…
Many physically motivated extensions to general relativity (GR) predict significant deviations in the properties of spacetime surrounding massive neutron stars. We report the measurement of a 2.01 +/- 0.04 solar mass pulsar in a 2.46-hr…
We have performed detailed numerical calculations of the non-conservative evolution of close X-ray binary systems with intermediate-mass (2.0-6.0 M_sun) donor stars and a 1.3 M_sun accreting neutron star. We calculated the thermal response…
We report on the discovery of the companion star to the millisecond pulsar J1342+2822B in the globular cluster M3. We exploited a combination of near-ultraviolet and optical observations acquired with the Hubble Space Telescope in order to…
PSR J1903+0327 is a mili-second pulsar with a mass of 1.67 M_{\odot} in a highly eccentric orbit (e=0.44) around a main-sequence star. This unique system cannot be reconciled with current observations where milli-second pulsars are…
A young and undermassive white dwarf has been identified as the possible companion to the millisecond pulsar PSR B1620-26 in Messier 4. This association is important as it then helps constrain the mass of the third body in the system to be…
We report on the discovery of a binary pulsar, PSR J1740-3052, during the Parkes multibeam survey. Timing observations of the 570-ms pulsar at Jodrell Bank and Parkes show that it is young, with a characteristic age of 350 kyr, and is in a…
Low-mass white dwarfs (LMWDs) are believed to be exclusive products of binary evolution, as the Universe is not yet old enough to produce them from single stars. Because of the strong tidal forces operating during the binary interaction…
We present the identification of the companion star to the intermediate mass binary pulsar J1439-5501 obtained by means of ground-based deep images in the B, V and I bands, acquired with FORS2 mounted at the ESO-VLT. The companion is a…
We report on photometric and spectroscopic observations of white dwarf companions to four binary radio millisecond pulsars, leading to the discovery of companions to PSRs J0614-3329, J1231-1411 and J2017+0603. We place limits on the…
We present optical high-speed photometry of three millisecond pulsars with low-mass ($< 0.3 M_{\odot}$) white dwarf companions, bringing the total number of such systems with follow-up time-series photometry to five. We confirm the…
PSR J1811-1736 (P=104 ms) is an old (~1.89 Gyrs) binary pulsar (P_orb=18.8 d) in a highly eccentric orbit (e=0.828) with an unidentified companion. Interestingly enough, the pulsar timing solution yields an estimated companion mass 0.93…
We present infrared observations in search of a planet around the white dwarf, GD66. Time-series photometry of GD66 shows a variation in the arrival time of stellar pulsations consistent with the presence of a planet with mass > 2.4Mj. Any…
White dwarfs typically have masses in a narrow range centered at about 0.6 solar masses (Msun). Only a few ultra-massive white dwarfs (M>1.2 Msun) are known. Those in binary systems are of particular interest because a small amount of…