TAT Bloginteresting astrophysics storieshttp://www.tat.physik.uni-tuebingen.de/~tat/blog/feed.php2022-12-08T12:38:35+00:00A bizarre gamma-ray burst breaks the rules for these cosmic eruptions<p><img src="http://www.tat.physik.uni-tuebingen.de/~tat/blog/content/public/upload/120722lgstrange-grbfeat_0_o.jpg" alt="undefined" /></p>
<p><em>One possible origin for GRB 211211A, shown in this illustration, is a pair of compact stars merging (bright dots in the center) and emitting jets of radiation (green and purple beams). Heavy elements forming in the clouds of matter surrounding the stars emit light that is known as a kilonova.</em> <em>SAMUELE RONCHINI/GSSI 2022</em></p>
<p>By <strong>Lisa Grossman</strong><br />8.12.2022</p>
<p>Astronomers have spotted a bright gamma-ray burst that upends previous theories of how these energetic cosmic eruptions occur.</p>
<p>For decades, astronomers thought that GRBs came in two flavors, long and short — that is, lasting longer than two seconds or winking out more quickly. Each type has been linked to different cosmic events. But about a year ago, two NASA space telescopes caught a short GRB in long GRB’s clothing: It lasted a long time but originated from a short GRB source.</p>
<p>“We had this black-and-white vision of the universe,” says astrophysicist Eleonora Troja of the Tor Vergata University of Rome. “This is the red flag that tells us, nope, it’s not. Surprise!”</p>
<p>This burst, called GRB 211211A, is the first that unambiguously breaks the binary, Troja and others report December 7 in five papers in Nature and Nature Astronomy.</p>
<p>Prior to the discovery of this burst, astronomers mostly thought that there were just two ways to produce a GRB. The collapse of a massive star just before it explodes in a supernova could make a long gamma-ray burst, lasting more than two seconds (SN: 10/28/22). Or a pair of dense stellar corpses called neutron stars could collide, merge and form a new black hole, releasing a short gamma-ray burst of two seconds or less.</p>
<p> </p>
<p><a href="https://www.sciencenews.org/article/gamma-ray-burst-breaks-rules-kilonova?utm_source=email&utm_medium=email&utm_campaign=latest-newsletter-v2&utm_source=Latest_Headlines&utm_medium=email&utm_campaign=Latest_Headlines" target="_blank">See full text</a></p>
<p> </p>http://www.tat.physik.uni-tuebingen.de/~tat/blog/index.php?controller=post&action=view&id_post=3672022-12-08T12:38:35+00:00IceCube neutrinos give us first glimpse into the inner depths of an active galaxy<p><img src="http://www.tat.physik.uni-tuebingen.de/~tat/blog/content/public/upload/image970enlarge-1_0_o.jpg" alt="undefined" /></p>
<p>Hubble image of the spiral galaxy NGC 1068. Credit: NASA/ESA/A. van der Hoeven</p>
<p>Posted on November 3, 2022 by Staff</p>
<p>The detection was made at the National Science Foundation-supported IceCube Neutrino Observatory, a massive neutrino telescope encompassing 1 billion tons of instrumented ice at depths of 1.5 to 2.5 kilometers below Antarctica’s surface near the South Pole. This unique telescope, which explores the farthest reaches of our universe using neutrinos, reported the first observation of a high-energy astrophysical neutrino source in 2018. The source, TXS 0506+056, is a known blazar located off the left shoulder of the Orion constellation and 4 billion light-years away.</p>
<p>“One neutrino can single out a source. But only an observation with multiple neutrinos will reveal the obscured core of the most energetic cosmic objects,” says Francis Halzen, a professor of physics at the University of Wisconsin–Madison and principal investigator of IceCube. He adds, “IceCube has accumulated some 80 neutrinos of teraelectronvolt energy from NGC 1068, which are not yet enough to answer all our questions, but they definitely are the next big step towards the realization of neutrino astronomy.”</p>
<p>Unlike light, neutrinos can escape in large numbers from extremely dense environments in the universe and reach Earth largely undisturbed by matter and the electromagnetic fields that permeate extragalactic space. Although scientists envisioned neutrino astronomy more than 60 years ago, the weak interaction of neutrinos with matter and radiation makes their detection extremely difficult. Neutrinos could be key to our queries about the workings of the most extreme objects in the cosmos.</p>
<p> </p>
<p><a href="https://icecube.wisc.edu/news/press-releases/2022/11/icecube-neutrinos-give-us-first-glimpse-into-the-inner-depths-of-an-active-galaxy/" target="_blank">Full story</a></p>
<p> </p>http://www.tat.physik.uni-tuebingen.de/~tat/blog/index.php?controller=post&action=view&id_post=3662022-11-03T23:20:58+00:00Emanuele Berti has received the 2023 Richard A. Isaacson Award in Gravitational-Wave Science<p> </p>
<p><img src="http://www.tat.physik.uni-tuebingen.de/~tat/blog/content/public/upload/fe9s-j2vuaajn96_0_o.jpeg" alt="undefined" /></p>
<p>Richard A. Isaacson Award in Gravitational-Wave Science</p>
<p> </p>
<p>This award recognizes outstanding contributions in gravitational-wave physics, gravitational-wave astrophysics, and the technologies that enable this science.</p>
<p>The annual award consists of $5,000, a certificate, travel reimbursement and a registration waiver to attend the APS April Meeting to give an invited talk and accept the award.</p>
<p> </p>
<p><a href="https://aps.org/programs/honors/prizes/isaacson.cfm" target="_blank">See full text</a></p>
<p> </p>http://www.tat.physik.uni-tuebingen.de/~tat/blog/index.php?controller=post&action=view&id_post=3652022-10-15T08:34:24+00:00Scientists Just Detected a Colossal Gamma-Ray Burst, And It's a Record-Breaker<p><img src="http://www.tat.physik.uni-tuebingen.de/~tat/blog/content/public/upload/gamma-ray-burst-art_0_o.jpg" alt="undefined" />An artist's impression of a gamma-ray burst. (ESO/A. Roquette)</p>
<p>12 October 2022<br />By MICHELLE STARR</p>
<p>Observatories around the world have just detected a colossal flare of extremely energetic radiation described as "record-breaking".</p>
<p>The event, first detected on October 9, was so bright that it was initially confused for an event closer to home. Initially dubbed Swift J1913.1+1946, it was thought to be a brief flash of X-rays from a not-too-distant source. It was only through further analysis that astronomers discovered the true nature of the glow – a gamma-ray burst, one of the most violent explosions in the Universe, now re-named GRB221009A.</p>
<p>Though further away, it was still one of the closest seen yet, just 2.4 billion light-years away. Moreover, this exceptionally bright gamma-ray burst appears to be the most energetic ever detected, coming in at up to 18 teraelectronvolts.</p>
<p>To be clear, though this proximity happens to be 20 times closer than the average long gamma-ray burst, it poses absolutely no danger to life on Earth.</p>
<p>Rather, it's tremendously exciting – an event that could shed new light (pun intended) on these fascinating explosions. Although its closeness makes it appear brighter in our sky, GRB221009A is possibly the most intrinsically bright gamma-ray burst we've ever seen.</p>
<p> </p>
<p><a href="https://www.sciencealert.com/scientists-just-detected-a-colossal-gamma-ray-burst-and-its-a-record-breaker" target="_blank">See full text</a></p>
<p> </p>http://www.tat.physik.uni-tuebingen.de/~tat/blog/index.php?controller=post&action=view&id_post=3642022-10-15T08:27:30+00:00