High-energy Variability of PSR J1311-3430

• Published in: The Astrophysical journal Vol. 850; no. 1; pp. 100 - 109
• Main Authors: An, Hongjun, Romani, Roger W., Johnson, Tyrel, Kerr, Matthew, Clark, Colin J.
• Format: Journal Article
• Language: English
• Published: Philadelphia The American Astronomical Society 20.11.2017; IOP Publishing; Institute of Physics (IOP)
• Subjects: ASTRONOMY AND ASTROPHYSICS; Astrophysics; binaries: close; Flares; Gamma rays; gamma-rays: stars; Millisecond pulsars; Power law; pulsars: individual (PSR J1311-3430); X-rays: binaries; XMM (spacecraft)
• ISSN: 0004-637X; 1538-4357; 1538-4357
• DOI: 10.3847/1538-4357/aa947f

We have studied the variability of the black-widow-type binary millisecond pulsar PSR J1311−3430 from optical to gamma-ray energies. We confirm evidence for orbital modulation in the weak off-pulse 200 MeV emission, with a peak at , following pulsar inferior conjunction. The peak has a relatively hard spectrum, extending above ∼1 GeV. XMM-Newton and Swift UV observations also show that this source's strong X-ray flaring activity is associated with optical/UV flares. With a duty cycle of ∼7%-19%, this flaring is quite prominent with an apparent power-law intensity distribution. Flares are present at all orbital phases, with a slight preference for . We explore possible connections of these variabilities with the intrabinary shock and magnetic activity on the low-mass secondary.