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arXiv · 1710.06097

High-Energy Variability of PSR J1311-3430

Hongjun An·Roger W. Romani·Tyrel Johnson·Matthew Kerr·Colin J. Clark
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Abstract

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 $\ge$200-MeV emission, with a peak at $\phi_B\approx 0.8$, following pulsar inferior conjunction. The peak has a relatively hard spectrum, extending above $\sim 1$\,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 $\sim 7-19$%, this flaring is quite prominent with an apparent power-law intensity distribution. Flares are present at all orbital phases, with a slight preference for $\phi_B=0.5-0.7$. We explore possible connections of these variabilities with the intrabinary shock and magnetic activity on the low mass secondary.

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Hongjun An, Roger W. Romani, Tyrel Johnson, Matthew Kerr, Colin J. Clark. 2017-10-17. High-Energy Variability of PSR J1311-3430. https://doi.org/10.3847/1538-4357%2Faa947f

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