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A massive gamma-ray bubble is generating intense cosmic rays
Recent astronomical discoveries have unveiled a giant gamma-ray bubble in the Cygnus star-forming region that is proving to be a significant source of extreme cosmic rays. This discovery, made by the Large High Altitude Air Shower Observatory (LHAASO) Collaboration in China, has shed new light on the origins of cosmic rays with unprecedented energy levels.
The gamma-ray burst, designated GRB 221009A, was found to be more powerful than 10 peta-electronvolts (PeV), which is over ten times the average energy of such bursts. This makes it the brightest and most energetic gamma-ray burst ever studied by astronomers. The team, led by Professor Cao Zhen from the Institute of High Energy Physics of the Chinese Academy of Sciences, was able to accurately measure the energy spectrum of the burst, providing crucial insights into the nature of cosmic rays.
The LHAASO Collaboration, which comprises over 280 members from 32 astrophysics research institutions worldwide, used a range of detectors and telescopes to study cosmic rays. Their observatory, located at a high altitude on Mount Haizi in Sichuan Province, China, is dedicated to unraveling the mysteries of these high-energy particles.
One of the most intriguing aspects of the discovery is the identification of a massive cosmic ray accelerator near the center of the gamma-ray bubble. This accelerator is believed to be associated with the Cygnus OB2 star cluster, which contains young massive stars with intense radiation pressures. The collisions between stellar winds generated by these stars and the interstellar medium create an ideal environment for particle acceleration, leading to the production of high-energy gamma rays.
These findings have far-reaching implications for our understanding of astrophysical processes and could challenge existing models of galaxy formation and cosmic ray transport in the Milky Way. Additionally, the discovery of such an extreme cosmic ray source opens up new avenues for testing fundamental physics theories, such as Special Relativity and the nature of Dark Matter.
Overall, the investigation into this gamma-ray bubble and its cosmic ray accelerator represents a significant leap forward in our quest to comprehend the most energetic phenomena in the Universe. As scientists continue to delve deeper into the mysteries of cosmic rays and gamma-ray bursts, we can expect more groundbreaking discoveries that will reshape our understanding of the cosmos.
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University of Wisconsin-Milwaukee and Protesters reach an agreement to dismantle encampment
Protesters at the University of Wisconsin-Milwaukee have agreed to end their pro-Palestinian encampment following an agreement reached with the school, university officials announced on Sunday. The encampment, which had been in place for two weeks, will be dismantled by Tuesday, marking the end of what was believed to be the last standing encampment at a Wisconsin college.
University officials had allowed the encampment to remain on a patch of lawn between Mitchell Hall and a busy thoroughfare on the campus’s southern boundary, opting not to involve law enforcement. This approach differed from the response at the University of Wisconsin-Madison, where police were called in to remove tents after negotiations fell through. Despite initial efforts to disband the encampment, Wisconsin-Madison eventually reached an agreement with protesters to voluntarily dismantle the camp prior to commencement ceremonies.
Chancellor Mark Mone of Wisconsin-Milwaukee stated last Wednesday that the university had exhibited “the widest possible amount of patience and restraint.” However, he also cautioned that patience was wearing thin and hinted at potential action by the school. Following discussions with the UWM Popular University for Palestine Coalition, the university agreed to advocate for a cease-fire between Israel and Hamas, condemn the destruction of schools and universities in Gaza by Israeli forces, and hold meetings with protest leaders regarding university investments.
Additionally, the university pledged to urge the Water Council, a Milwaukee organization of water technology companies, to sever connections with two Israeli government-owned entities, Mekorot and the Israel Innovation Authority. Chancellor Mone serves as the treasurer on the Water Council’s board of directors.
In return for these commitments, the protesters agreed to dismantle the encampment beginning on Sunday and completing the process by Tuesday. They also agreed not to disrupt the university’s commencement ceremonies scheduled for Sunday. In a statement, the protesters expressed their satisfaction with the agreement, stating, “After hard fought edits and careful consideration by the coalition, we determined we had obtained all possible benefits from the encampment.”
The resolution of the encampment at the University of Wisconsin-Milwaukee represents a successful outcome of negotiations between university officials and protesters. By reaching a compromise that addresses the concerns of both parties, a peaceful resolution has been achieved, allowing for the encampment to be taken down without incident.