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)

Comments

A SIGNIFICATIVE FRACTION OF BARYONS RESIDE IN THE FILAMENTS OF THE COSMIC WEB

(Credit: NASA, ESA, and E. Hallman (University of Colorado, Boulder) Observations of the cosmic microwave background indicate that baryons (protons, neutrons, etc., - the ordinary matter just to understand) occupies only 5% of the total energy content of the Universe (95% is dark matter and dark energy). However in the local universe approximately half of this "ordinary" matter it has never been observed.

A UNIVERSE WITHOUT A CENTER?

Image Credit: Eugenio Bianchi, Carlo Rovelli & Rocky Kolb. According to the standard theories of cosmology, there is no center of the universe. In a conventional explosion, material expand out from a central point and the instinct suggests that with the Big Bang happened something similar. But the Big Bang was not an explosion like that at all: it was an explosion of space, not an explosion in space . The Big Bang happened everywhere in the Universe.

A Sapphire Super-Earth

Twenty-one light years away, in the constellation Cassiopeia, a planet by the name of HD219134 b orbits its star with a year that is just three days long. With a mass almost five times that of Earth, it is what is known as a super-Earth. Unlike our planet, however, these super-Earths were formed at high temperatures close to their host star and contain high quantities of calcium, aluminum and their oxides – including sapphire and ruby. HD219134 b is one of three candidates likely to belong to a new, exotic class of exoplanets. These objects are completely different from the majority of Earth-like planets. They have 10 to 20 percent lower densities than Earth. Researchers looked at different scenarios to explain the observed densities. For example, a thick atmosphere could lead to a lower overall density. But two of the exoplanets studied, 55 Cancri e and WASP-47 e, orbit their star so closely that their surface temperature is almost 3,000 degrees and they would have lost this ...

SpaceTime

Search This Blog