RAPIDLY ROTATING PULSARS AS POSSIBLE SOURCES OF FAST RADIO BURSTS

Image: Artist's impression of a magnetar. Credit: ESO/L. Calçada

In a recent paper (Lyutikov et al. 2016) the authors discuss possible association of fast radio bursts (FRBs) with supergiant pulses emitted by young pulsars (ages ~ tens to hundreds of years) born with regular magnetic field but very short - few milliseconds - spin periods.
A fast radio burst (FRB) is a high-energy astrophysical phenomenon manifested as a transient radio pulse lasting only a few milliseconds. They are bright, unresolved, broadband, millisecond flashes, found in parts of the sky outside the Milky Way.

The authors argued that the physical constraints imposed by the properties of FRBs limit their origin to the magnetospheres of neutron stars. Two special types could satisfy those constraints: fast rotating young neutron stars (using the rotational energy to generate FRBs), or very high magnetic fields neutron stars - magnetars (using the magnetic energy).

The key distinction between the two possibilities would be a detection of high energy emission contemporaneous with an FRB - Crab giant pulses do not show high energy signals.

Lyutikov et al. 2016 (preprint) - Fast radio bursts as giant pulses from young rapidly rotating pulsars - (arXiv)

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‘Monster’ Planet Discovery Challenges Formation Theory

Artist’s illustration of a "hot Jupiter". Image Credit: NASA/CXC/M. Weiss A new research presents the discovery of NGTS-1b, a hot-Jupiter transiting an early M-dwarf host in a P~2.6 days orbit discovered as part of the Next Generation Transit Survey (NGTS). The planet has a mass of M~0.8 M(jupiter) making it the most massive planet ever discovered transiting an M-dwarf. NGTS-1b is the third transiting giant planet found around an M-dwarf, reinforcing the notion that close-in gas giants can form and migrate similar to the known population of hot Jupiters around solar type stars. The existence of the 'monster' planet, 'NGTS-1b', challenges theories of planet formation which state that a planet of this size could not be formed around such a small star. According to these theories, small stars can readily form rocky planets but do not gather enough material together to form Jupiter-sized planets. Such massive planets were not thought to exist ar...

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