Using sensitive instruments aboard ESA’s International Gamma-ray Astrophysics Laboratory (Integral) mission, astronomers GRB231115A Taken from the center of Messier 82 (M82, NGC 3034, or the Cigar Galaxy). Messier 82 (M82, NGC 3034, or Cigar Galaxy) is a starburst irregular galaxy located 12 million light-years away in the constellation Ursa Major. They say the spectral and timing characteristics of GRB 231115A, as well as the lack of X-ray and optical observations and gravitational wave signals several hours after the event, indicate that this outburst was the result of a giant flare from a magnetar. Suggests. They conclude that starburst galaxies like Messier 82, which are known to produce magnetars, could be promising targets for studying giant flares.
On November 15, 2023, Integral detected a burst of gamma rays that lasted just one-tenth of a second. The detection was sent to the Integral Science Data Center, where software determined it came from the nearby galaxy Messier 82. A small square on Integral's map indicates the location of the burst. Blue circles on the two cropped images indicate corresponding locations. Image credit: ESA / Integral / XMM-Newton / INAF / TNG / M. Rigoselli, INAF.
Giant flares are short explosive events that release very large amounts of energy as gamma-ray bursts (GRBs).
Only three such flares have been observed from magnetars in our Milky Way galaxy and the nearby Large Magellanic Cloud in the past roughly 50 years.
Observations of giant flares from distant magnetars are hampered by the fact that at long distances it is difficult to identify the source of the energy burst.
“Some young neutron stars have very strong magnetic fields, more than 10,000 times stronger than a typical neutron star. These are called magnetars. They emit energy as flares, and sometimes these flares can be huge,” said ESA astronomer Dr. Ashley Climes.
“However, in the past 50 years of gamma-ray observations, huge flares from our galaxy's magnetars have only been observed three times.”
“These explosions are extremely powerful. The explosion detected in December 2004 came from 30,000 light-years away from us, but was still powerful enough to affect the upper layers of Earth's atmosphere. It's like a solar flare coming from much closer to us.
“The flare detected by Integral is the first confirmation of the existence of a magnetar outside the Milky Way,” said Dr. Sandro Meleghetti, an astronomer at the National Institute of Astrophysics.
“We suspect that some of the other 'short gamma-ray bursts' revealed by Integral and other satellites are also giant flares from magnetars.”
“This discovery will begin the search for other extragalactic magnetars. If we can find more stars, we will be able to understand how often these flares occur and how the stars lose energy in the process. We can begin to understand that,” Dr. Cromes said.
“However, such short-lived explosions can only be caught by chance if the observatory is already pointing in the right direction,” said Dr. Jan-Uwe Ness, a scientist at the Integral project.
“This makes Integral, with its wide field of view more than 3,000 times the area of the sky covered by the Moon, extremely important for these detections.”
“Messier 82 is a bright galaxy in which star formation occurs,” the authors said.
“In these regions, massive stars are born, live short, turbulent lives, and leave behind neutron stars.”
“The discovery of magnetars in this region confirms that magnetars are likely young neutron stars.”
“The search for additional magnetars will continue in other star-forming regions to understand these extraordinary objects.”
of findings It was published in the magazine Nature.
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S. Meleghetti other. A giant magnetar flare in the nearby starburst galaxy M82. Nature, published online March 7, 2024. doi: 10.1038/s41586-024-07285-4
Source: www.sci.news
