Second repeating fast radio burst discovered in space
What in news:
· The discovery of the extragalactic signal is among the first, eagerly awaited results from the Canadian Hydrogen Intensity Mapping Experiment (CHIME).
About the News:
· Scientists have detected the second repeating fast radio burst (FRB) ever recorded, which may help better understand the source of these mysterious signals originating from far outside our Milky Way galaxy.
· FRBs are believed to emanate from powerful astrophysical phenomena billions of light years away.
· However, the source of these signals are not well understood.
· The discovery of the extragalactic signal is among the first, eagerly awaited results from the Canadian Hydrogen Intensity Mapping Experiment (CHIME), a radio telescope inaugurated in 2017.
· Until now, there was only one known repeating FRB.
· And with more repeaters and more sources available for study, we may be able to understand these cosmic puzzles — where they’re from and what causes them.
· The repeating FRB was one of a total of 13 bursts detected over a period of just three weeks during the summer of 2018.
· The majority of the 13 FRBs detected showed signs of “scattering,” a phenomenon that reveals information about the environment surrounding a source of radio waves.
· The amount of scattering observed by the CHIME team led them to conclude that the sources of FRBs are powerful astrophysical objects more likely to be in locations with special characteristics.
· That could mean in some sort of dense clump like a supernova remnant,” said Cherry Ng, an astronomer at the University of Toronto in Canada.
Fast radio bursts:
· FRB’s are intense bursts of radio emission that have durations of milliseconds and exhibit the characteristic dispersion sweep of radio pulsars.
· The first was discovered in 2007 by Lorimer et al., although it was actually observed some six years earlier, in archival data from a pulsar survey of the Magellanic clouds.
The Canadian Hydrogen Intensity Mapping Experiment (CHIME)
· CHIME an interferometric radio telescope at the Dominion Radio Astrophysical Observatory in British Columbia, Canada.
· It consists of four semi-cylinders populated with 1024 dual-polarization radio receivers sensitive at 400–800 MHz.
· The telescope has no moving parts and observes half of the sky each day as the Earth turns.
· CHIME's daily survey of the sky will enable study of our own Milky Way galaxy, in radio frequencies, and is expected to improve the understanding of galactic magnetic fields.
· CHIME will also detect the mysterious extragalactic fast radio bursts (FRB) that last just milliseconds and have no known astrophysical explanation
· It will also help to calibrate measurements of radio waves from rapidly spinning neutron stars use to detect gravitational waves.
Expected prelims question:
Consider the following statements
1. CHIME is an interferometric radio telescope.
2. CHIME only detects mysterious extragalactic fast radio bursts (FRB).
Which of the above statements are correct.
a) Only 1
b) Only 2
c) Both 1 and 2
d) None of above
Ans - a
Expected mains question
What do you understand by term fast radio bursts in cosmology. Add anote on CHIME in relation to FRB.