Astronomers observe a mysterious explosion of energy for the first time
For the first time, astronomers have observed one of the strongest flashes found so far in the sky, and it appeared as a result of a collision between a star and a “neutron star” (a small body whose radius does not exceed 30 km, but is characterized by the density of its substance and the intensity of its gravity), as it is called.
This was done by radio astronomy in the millimeter range of radio frequency wavelengths, providing an unprecedented view of one of the most violent astronomical events in the universe.
A research team led by Northwestern University in the US state of Illinois and Radboud University in the Netherlands used the Atacama Large Millimeter/ Submillimeter Array in Chile, referred to as the ALMA Radio Telescope for short, to capture That glow caused by what was called “GRB 211106A” (GRB 211106A), knowing that it is a short gamma-ray burst (a gamma ray flux or “GRB” for short) was found to have originated in a galaxy 20 billion light-years away from Earth.
Talking about this discovery, Wen Fei Fong, a professor of physics and astronomy at Northwestern University, said that "this short burst of gamma rays was the first time we had attempted to observe such an event using ALMA." It is very difficult to spot flares after short bursts, so it was amazing to catch this cosmic event shining so brightly.”
Dr. Fong is one of a large group of researchers who participated in a study on this observation process that will be published in a future issue of the Astrophysical Journal Letters, knowing that it is now available electronically at arxiv.org in the form of A draft that has not yet been peer-reviewed.
As a reminder, “gamma ray bursts” (GRBs) are powerful flashes of gamma rays emitted when massive stars at the end of their life cycle collapse to form black holes, or merging, or colliding, dense neutron stars into a binary system of two stars, with Stars accompany them to form a black hole, a violent and intense cosmic collision believed to be responsible for the presence of most of the world's heavy metals such as gold and plutonium.
In a statement he made in this regard, the astronomer at Radboud University and the lead researcher in the scientific paper Tanmo Laskar said that “collisions occur as a result of radiation left by gravitational waves (very fast, invisible waves that ripple in space and travel at the speed of light and are capable of causing disturbance). As it passes through the fabric of space-time (which was predicted by Albert Einstein in his general theory of relativity) it removes energy from the orbit of binary stars, causing the stars to rotate towards each other.”
The researcher added, explaining that “the resulting explosion was accompanied by flows of radiation and gas moving at a speed almost equal to the speed of light. When one of these radiations goes to Earth, we detect a short pulse of “gamma rays,” or “streams of short duration” gamma rays.
Short-duration "gamma-ray bursts" last only a fraction of a second, while their glow stays in longer, less energetic wavelengths of light over minutes or even days.
This was the case with “GRP 211106A”, as the resulting glow was first detected in X-ray light by the “Neil Gerals Swift Observatory” of the US Space Agency “NASA”, and then it was observed in infrared light by the “Hubble Telescope”. Satellite, and finally in the light of millimeter radio by “ALMA”.
Only in the last observations made by ALMA, it was found that the "gamma ray flux" came from a distant galaxy.
Dr. Laskar explained that "the observations made by the "Hubble Telescope" revealed an unchanging field of galaxies. The unparalleled sensitivity of the ALMA matrix allowed us to more precisely locate the gamma ray flux in this field, and it turned out to be in a faint galaxy far beyond our own.
This in turn means that this short-duration gamma-ray burst is more powerful than we first thought, making it one of the brightest and most energetic of all.”
Thanks to the wavelength in the millimeter range, the scientists also obtained a clearer picture of the structure and density of the environment surrounding the “gamma ray flux”, according to Dr. Fong, and also allowed the researchers to measure the apparent width of the radiation and gas flow that led to the explosion by only more than 15 degrees, which constitutes one of the The widest ranges ever measured.
The study highlights the importance of observing and observing complex cosmic phenomena at multiple wavelengths using the most advanced instruments at hand, which now include the newly launched James Webb Space Telescope (JWST).
"In the future, we can also use the James Webb Space Telescope to capture infrared flares and study their chemical composition," said Dr. Laskar. "I am excited about these upcoming discoveries in our field."
Source: The Independent
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