Free Astronomy Magazine September-October 2025 ARABIC VERSION

complexnatureofGRBsatveryhigh energies.Theresultssupporttheo- reticalmodelsinwhichthesebursts generate structured, multi-layered jetswhereparticlesareaccelerated. GRBsareamongtheUniverse’smost powerful phenomena, releasing in justsecondsasmuchenergyasthe Sunemitsoveritsentirelifetime.As their name suggests, they burst over a brief, prompt phase, lasting sec- onds to minutes, and then are fol- lowedbyanafterglowthatcanfade overhourstomonths.GRBsareclas- sifiedasshortorlongbasedonthe duration of the burst: long GRBs are thought to be linked to excep- tionally bright supernovae, while short GRBs likely result from neu- tronstarcollisions.Despitetheirin- tensebrightness,theseextragalactic sourcesarechallengingtodetectat the highest energies because the gammaraystheyemitweakenover thevastdistancestheytravel,aswell as due to their transient nature. On 9 October 2022, space-based ob- servatories, such as NASA’s Fermiand Swift satellites, detected an ex- tremely bright long GRB, namedGRB221009A. “Dubbedthe‘BOA T’ (Brightest Of All Time), the burst wassointensethatitsaturatedmul- tiple instruments observing it, and triggered follow-up observations across the globe,” explains Alicia López Oramas, researcher at the IAC and Publications Manager of LST Collaboration. “BOAT is a unique event:itisestimatedthattherewill be one GRB per millennium withthis intensity,” she adds. TheLST-1telescope,locatedatthe CTAO’s northern array site in La Palma (Canary Islands, Spain), be- gan observing the event just 1.33 days after the initial explosion. Spanning over 20 days after the GRB onset, the observations with the LST-1 enabled the LST Collab- oration to identify an excess of gammarays. “Whilethisexcessdid rtist’simpressionofagamma-ray burst. [ESO/A. Roquette] SEPTEMBER-OCTOBER2025 A ﻣﺠﻠﺔ FreeAstronomy ﺎﻟﻌﺮ ﺔ 23 ﺗﺪﻋﻢ ﻫﺬه اﻟﻨﺘﺎﺋﺞ اﻟﻨﻤﺎذج اﻟﻨﻈﺮﻳﺔ اﻟﺘﻲ ﺗﻮﻟﺪ ﻓﻴﻬﺎ ﻫﺬه اﻻﻧﻔﺠﺎرات ﻧﻔﺎﺛﺎت ﻣﻨﻈﻤﺔ ﻣﺘﻌﺪدة اﻟ ﻄﺒﻘﺎت ﺣﻴﺚ ﻳﺘﻢ ﺗﴪﻳﻊ اﻟﺠﺴﻴﻤﺎت ﻌـﺪ ﺗ. اﻧﻔﺠﺎرات أﺷﻌﺔ ﻏﺎﻣﺎ ﻣـﻦ أﻗـﻮى اﻟﻈـﻮاﻫﺮ اﻟﻜﻮﻧﻴﺔ ﺣﻴﺚ ﺗﻄﻠﻖ ﰲ ﺛﻮانٍ ﻓﻘﻂ ﻗـﺪر اً ﻣـﻦ اﻟﻄﺎﻗﺔ ﻳﻌـﺎدل ﻣـﺎ ﺗ ﺒﻌﺜـﻪ اﻟ ﺸـﻤﺲ ﻃـﻮال . ﻋﻤﺮﻫﺎ وﻛﻤﺎ ﻳﻮﺣﻲ اﺳﻤﻬﺎ ﻓﺈ ﻧﻬﺎ ﺗﻨﻔﺠـﺮ ﰲ ﻣﺮﺣﻠﺔ ﻗﺼ ة وﴎﻳﻌﺔ ﺗﺴﺘﻤﺮ ﻣﻦ ﺛـﻮانٍ إﱃ دﻗﺎﺋﻖ ﺛﻢ ﻳﺘﺒﻌﻬﺎ ﺗﻮﻫﺞ ﻳﻤﻜﻦ أن ﻳﺘﻼﳽ ﻋﲆ ﻣــﺪار ﺳــﺎﻋﺎت إﱃ أﺷــﻬﺮ . ﻳــﺘﻢ ﺗﺼــﻨﻴﻒ اﻧﻔﺠﺎرات أﺷﻌﺔ ﻏﺎﻣﺎ ﻋـﲆ أﻧﻬـﺎ أو ﻗﺼـ ة ﻃﻮﻳﻠﺔ ﺑﻨﺎءً ﻋـﲆ ﻣـﺪة اﻻﻧﻔﺠـﺎر ﻳ: ﻌﺘﻘـﺪ أن اﻧﻔﺠـﺎر ات أﺷـﻌﺔ ﻏﺎﻣـﺎ اﻟﻄﻮﻳﻠـﺔ ﻣﺮﺗﺒﻄـﺔ ﺑﺎ ﺴــﺘﻌﺮ ات اﻟﻌﻈﻤــﻰ اﻟﺴــﺎﻃﻌﺔ ﺑﺸــﻜﻞ اﺳــﺘﺜﻨﺎﺋﻲ ﺑﻴﻨﻤــﺎ ﻣــﻦ ا ﺤﺘﻤــﻞ أن ﺗﻨــﺘﺞ اﻧﻔﺠــﺎرات أﺷــﻌﺔ ﻏﺎﻣــﺎ اﻟﻘﺼــ ة ﻋــﻦ ﺗﺼﺎدﻣﺎت اﻟﻨﺠﻮم اﻟﻨﻴﻮﺗﺮوﻧﻴﺔ وﻋـﲆ اﻟـﺮﻏﻢ ﻣﻦ ﺳﻄﻮﻋﻬﺎ اﻟ ﺸﺪﻳﺪ ﻓﺈن ﻫﺬه ا ﺼﺎدر ﺧﺎرج ا ﺠﺮة ﺗﺸﻜﻞ ﺗﺤﺪﻳ ﺎً ﻟﻠﻜﺸﻒ ﻋﻨﻬﺎ ﻋﻨﺪ أﻋـﲆ اﻟﻄﺎﻗﺎت ﻷن أﺷﻌﺔ ﻏ ﺎﻣﺎ اﻟﺘﻲ ﺗﻨﺒﻌـﺚ ﻣﻨﻬـﺎ ﺗﺘﻀـﺎءل ﻣ ـ ﻊ ا ﺴــﺎﻓﺎت اﻟﺸﺎﺳـﻌﺔ اﻟﺘــﻲ ﺗﺴﺎﻓﺮﻫﺎ ﺑﺎﻹﺿﺎﻓﺔ إﱃ ﻃﺒﻴﻌﺘﻬﺎ اﻟﻌﺎﺑﺮة . ﰲ 9 أﻛﺘﻮﺑﺮ 2022 رﺻﺪت ﻣﺮاﺻـﺪ ﻓﻀـﺎﺋﻴﺔ ﻣﺜﻞ أ ﻗﻤﺎر ﻓ ﻣﻲ وﺳﻮﻳﻔﺖ اﻟﺘﺎﺑﻌـﺔ ﻟﻨﺎﺳـﺎ اﻧﻔﺠﺎر أﺷﻌﺔ ﻏﺎﻣﺎ ﻃﻮﻳـﻞ ﺷـﺪﻳﺪ اﻟﺴـﻄﻮع ﻤﻲﺳ GRB221009A وﺗﻮﺿﺢ أﻟﻴﺴﻴﺎ ﻟﻮﺑﻴﺰ أوراﻣﺎس اﻟﺒﺎﺣﺜﺔ ﰲ ا ﺮﻛـﺰ اﻟﻔﻠﻜـﻲ اﻟـﺪوﱄ وﻣﺪﻳﺮة ﻣﻨﺸﻮرات ﻣﴩوع ﺗﻠﺴﻜﻮب اﻟﻔﻀﺎء اﻟﻜﺒ (LST) ": أُﻃﻠﻖ ﻋﲆ اﻻﻧﻔﺠـﺎر اﺳـﻢ BOAT ) أ ﻊ اﻧﻔﺠﺎر ﻋﲆ ﻣﺮ اﻟﻌﺼﻮر ( وﻛﺎن ﺷﺪﻳﺪ اﻟﻜﺜﺎﻓﺔ ﻟﺪرﺟﺔ أﻧﻪ أﻏﻠـﻖ اﻟﻌﺪﻳـ ﺪ ﻣـﻦ اﻷﺟﻬﺰة اﻟﺘﻲ ﺗﺮﺻـﺪه ﻣﻤـﺎ أدى إﱃ ﻋﻤﻠﻴـﺎت رﺻ ـﺪ ﻻﺣﻘــﺔ ﰲ ﺟﻤﻴــﻊ أﻧﺤــﺎء اﻟﻌــﺎﻟﻢ ." وﺗﻀﻴﻒ ﻳ : " ﻌﺪ اﻧﻔﺠﺎر BOAT ﺎً ﺣﺪﺛ إذ اً ﻓﺮﻳـﺪ ﻳﺤﺪث اﻧﻔﺠﺎر أﺷﻌﺔ ﻏﺎﻣﺎ ﺑﻬﺬا ا ﺴﺘﻮى ﻣﺮة واﺣﺪ ﻛﻞ أﻟﻒ ﻋﺎم ." ﺑﺪأ ﺗﻠﺴـﻜﻮب LST-1) ( اﻟﻮاﻗﻊ ﰲ ا ﻮﻗﻊ اﻟﺸـﻤﺎﱄ ﺮﺻـﺪ ﻣﺼـﻔﻮﻓﺔ ﺗﻠﺴﻜﻮﺑ ﺎت ﺗﺸ ﻳﻨﻜﻮف (CTAO) ﻻ ﺑﺎ ـﺎ ﰲ ) ﺟﺰر اﻟﻜﻨﺎري، إﺳﺒﺎﻧﻴﺎ ﺑ( ﺮﺻﺪ اﻟﺤـﺪث ﺑﻌـﺪ 1.33 ﺎً ﻳﻮﻣ ﻓﻘﻂ ﻣـﻦ اﻻﻧﻔﺠـﺎر اﻷوﱄ ﺑﻌـﺪ و ﻣﺮور أ ﻛﺜﺮ ﻣﻦ 20 ﺎً ﻳﻮﻣ ﻋـﲆ ﺑﺪاﻳـﺔ اﻧﻔﺠـﺎر أﺷﻌﺔ ﻏﺎﻣﺎ ﻣﻜﻨﺖ اﻷرﺻﺎد ﺑﺎﺳﺘﺨﺪام ﺗﻌﺎون اﻟﺘﻠﺴﻜﻮب اﻟﻜﺒ ) (LST-1 ﻣﻦ ﺗﺤﺪﻳﺪ ﻛﻤﻴﺔ ﻛﺒ ة ﻣﻦ أﺷﻌﺔ ﺎﻣﺎﻏ ا ﻨﺒﻌﺜﺔ . رﺳــــــﻢ ﺗﺨ ﻠـــــــﻲ ﻈﻬـــــــﺮ اﻧﻔﺠــــــﺎر أﺷـــــــﻌﺔ ﻏﺎﻣـــــــﺎ . [ESO/A. Roquette] ﺳﺒﺘﻤﺒﺮ - ﺃﻛﺘﻮﺑﺮ 2 0 2 5