Related papers: Multiband Optical Light Curves of Black-Widow Puls…

We are monitoring established and putative redback millisecond pulsars (MSPs) in time-series photometry, repeatedly covering their 5-6 hr orbital light curves in $r^{\prime}$ or $R$. On timescales of months, PSR J1048+2339 and XMMU…

Binary systems composed of a recycled millisecond pulsar and a stellar companion in close orbit could be excellent sites to diagnose pulsar winds. In such systems, the pulsar outflow irradiates and heats up the companion atmosphere, which…

We describe a near-IR photometric search for cool red dwarf companions to hot EUV-detected white dwarfs (WDs). While some composite systems have been found optically among WDs detected in recent EUV All-Sky Surveys, we develop an IR…

We have obtained initial spectroscopic observations and additional photometry of the newly discovered Pb=94min gamma-ray black-widow pulsar PSR J1311-3430. The Keck spectra show a He-dominated, nearly H-free photosphere and a large…

I obtained time-series photometry of the compact binary candidate for the Fermi source 4FGL J0935.3+0901. Superposed on the 2.44 hr orbital modulation are day-to-day variations and frequent flaring as seen in several redback and black widow…

'Spider' binary systems - black widow and redback compact binaries differentiated by their companion's mass and nature - are an important type of pulsar system exhibiting a rich empirical phenomenology, including radio eclipses, optical…

We report on the determination of the astrometric, spin and orbital parameters for PSR J1953+1846A, a "black widow" binary millisecond pulsar in the globular cluster M71. By using the accurate position and orbital parameters obtained from…

We present a new analysis of the light curve for the secondary star in the eclipsing binary millisecond pulsar system PSR B1957+20. Combining previous data and new data points at minimum from the Hubble Space Telescope, we have 100%…

We describe the first X-ray observations of binary millisecond pulsars PSRs J0023+0923, J1810+1744, J2215+5135, and J2256-1024. All four are Fermi gamma-ray sources and three are 'black-widow' pulsars, with companions of mass < 0.1 solar…

Direct imaging surveys have discovered wide-orbit planetary-mass companions that challenge existing models of both star and planet formation, but their demographics remain poorly sampled. We have developed an automated binary companion…

PSR J1928+1815 is a 10.55 ms millisecond pulsar in a 3.6 hr orbit with a massive ($1.0$-$1.6\,M_{\odot}$) companion that produces extended radio eclipses. The companion, proposed to be a stripped helium star, is undetected in optical and…

Keck-telescope spectrophotometry of the companion of PSR J1810+1744 shows a flat, but asymmetric light-curve maximum and a deep, narrow minimum. The maximum indicates strong gravity darkening near the L_1 point, along with a heated pole and…

Context. PSR J0312$-$0921 and PSR J1627$+$3219 are black widow pulsars with orbital periods of 2.34 and 3.98 hours. They were recently detected in the radio and $\gamma$-rays. Aims. Our goals are to estimate the fundamental parameters of…

We report on the determination of astrometric, spin and orbital parameters for PSR J1518+0204C, a "black widow" binary millisecond pulsar in the globular cluster M5. The accurate position and orbital parameters obtained from radio timing…

We present the first X-ray observation of the energetic millisecond pulsar binary PSR J1431-4715, performed with XMM-Newton and complemented with fast optical multi-band photometry acquired with the ULTRACAM instrument at ESO-NTT. It is…

PSR J0636+5128 is a millisecond pulsar in one of the most compact pulsar binaries known, with a 96\,min orbital period. The pulsar mass function suggests a very low-mass companion, similar to that seen in so-called "black widow" binaries.…

We report the discovery of a new black-widow millisecond pulsar, PSR J1544-2555, associated with the Fermi-LAT source 4FGL J1544.2-2554. Optical, radio, and gamma-ray observations confirmed its nature as a compact spider binary system.…

We have used deep V and R images acquired at the ESO Very Large Telescope to identify the optical companion to the binary pulsar PSR J0610-2100, one of the black-widow millisecond pulsars recently detected by the Fermi Gamma-ray Telescope…

We modelled the radio and gamma-ray light curves of millisecond pulsars using outer gap, two-pole caustic, low-altitude slot gap, and pair-starved polar cap geometric models, combined with a semi-empirical conal radio model. We find that no…

We present Keck spectroscopic measurements of the millisecond pulsar binary J2215+5135. These data indicate a neutron-star (NS) mass M_NS=1.6Mo, much less than previously estimated. The pulsar heats the companion face to T_D~9000K; the…