Free Astronomy Magazine January-February 2024 ARABIC VERSION

absorbing material al- ways exists between the active galactic nu- cleus and us, the team has successfully cap- tured the accretion flow towards the ac- tive galactic nucleus. Furthermore, the re- search team has also elucidated the physi- cal mechanism re- sponsible for inducing this gas accretion. The observed gas disk ex- hibited a gravitational force so substantial that it could not be sustained by the pres- sure calculated from the motion of the gas disk. When this situa- tion arises, the gas disk collapses under its weight, forming complex structures and becoming inca- pable of maintaining stable motion at the galactic center. As a result, the gas rapidly falls towards the cen- tral black hole. ALMA has revealed this physical phenom- enon known as “grav- itational instability” at the galaxy’s heart. In addition, this study has significantly ad- vanced the quantitative understand- ing of gas flows around the active galactic nucleus. The accretion rate at which gas is supplied to the black hole can be calculated from the den- sity of the observed gas and the ve- locity of the accretion flow. Surprisingly, this rate was found to be 30 times greater than what is re- quired to sustain the activity of this active galactic nucleus. In other words, most of the accretion flow at the 1-light-year scale around the galactic center was not contributing to the growth of the black hole. So, where did this surplus gas go? This study also unravels this mys- tery—high-sensitivity observations of all phase gases with ALMA-de- tected outflows from the active galactic nucleus. Quantitative analysis revealed that most of the gas that flowed toward the black hole was expelled as atomic or molecular outflows. However, due to their slow ve- locities, they couldn’t escape from the grav- itational potential of the black hole and eventually returned to the gas disk. There, they were recycled back into an accretion flow towards the black hole, akin to a fountain, thus com- pleting a fascinating gas recycling process at the galactic cen- ter. Regarding the achievements of this study, Takuma Izumi states, “Detecting ac- cretion flows and outflows in a region just a few light-years around the actively growing supermas- sive black hole, partic- ularly in a multi- phase gas, and even deciphering the ac- cretion mechanism it- self, are indeed mon- umental achieve- ments in the history of supermassive black hole research.” He emphasizes the sig- nificance of this ac- complishment. Look- ing ahead to the fu- ture, he also continues, “To compre- hensively understand the growth of supermassive black holes in cosmic history, we need to investigate vari- ous types of supermassive black holes located farther away. This re- quires high-resolution and high-sen- sitivity observations, and we have high expectations for the further use of ALMA and for upcoming large radio interferometers in the next generation.”      ﻣﺠﻠﺔ FreeAstronomy ﺎﻟﻌﺮ ﺔ 40 ﺗﻮز ﻌـــــــﺎت أول أﻛﺴـــــــ ﺪ اﻟﻜﺮـــــــﻮن )CO ( ﻣﻤـــــــﺎ ﻌﻜـــــــﺲوﺟـــــــﻮد اﻟﻐـــــــﺎزاﻟـــــــﺬري وﺳـــــــ ﺎﻧ ﺪ ـﺪروﺟ اﻟﻬ (HCN) ﻣﻤـﺎ ﻌﻜـﺲوﺟـﻮد اﻟﻐـﺎزاﻟـ ـ ﻋـﺎﻟﻲ اﻟﻜﺜﺎﻓـﺔ ﺠﺰ ـﺐ وﺧـﻂ إﻋـﺎدة ﺗﺮﻛ ــﺪروﺟ اﻟﻬ ) H36 α و ( ﻌﻜــﺲوﺟــﻮد اﻟﻐــﺎزاﻟﻤﺘــﺄﻳﻦ ﻫــﻲ اﻟــﺬ ﻣـﺎ ــﺎﻟﻠﻮن ﻈﻬــﺮ اﻷ ﻤــﺮ واﻷزرق واﻷﺧﻀــــﺮواﻟــــﻮرد ﻋﻠــــﻰ اﻟﺘــــﻮاﻟﻲ ﺗ. ﻮﺟــــﺪ ﻧــــﻮاة ﻣﺠــــﺮة ﻧﺸــــﻄﺔ ﻓــــﻲ اﻟﻤﺮﻛــــﺰ وﻣــــﻦ ـﻞ ﻣﺎﺋـﻞ ﻣـﻦ اﻟﻤﻨـﺎﻃﻖ اﻟـ اﻟﻤﻌـﺮوف أن ﻫـﺬﻩ اﻟﻤﺠـﺮة ﻟﻬـﺎ ﻫﻴ ـﺔ ـﺨﺎرﺟ ﺔ إﻟـﻰ اﻟﻤﻨـﺎﻃﻖ اﻟﺪاﺧﻠ ــــﺚ ﺗﺸــــ ﮫ اﻟﻤﻨﻄﻘــــﺔ اﻟﻮﺳــــﻄﻰﻗﺮﺻــــ ﺣ ﺎً ــــ ﺗﻘﺮ ﺎً ــــﻒ ــــﻢ ﻗــــﺮص اﻟﻐــــﺎزاﻟﻤﺮﻛــــﺰي اﻟﻜﺜ ﻳ ﻠــــﻎ ﺣ ) اﻷﺧﻀﺮ ﺣﻮاﻟ ( ﻲﺳﺖﺳﻨﻮاتﺿﻮﺋ ﺔ : وﻗﺪ ﺗﻢ رﺻﺪ ـﺔ ذﻟﻚ ﻔﻀﻞ اﻟﺪﻗﺔ اﻟﻌﺎﻟ ﻟﻤﺮﺻـﺪ أﻟﻤـﺎ اﻧﻈـــﺮاﻟﺸـــ ﻞ اﻟـــﺪاﺧﻠﻲ ﻟﻠﺤﺼــــﻮل ﻋﻠـــﻰﻣﻨﻈـــﺮ ﻣﻜـــ . ﻨﺘﻘــــﻞ ﺗـــﺪﻓﻖ اﻟ ﻼزﻣـــﺎ ﺸـــ ﻞ ﻋﻤــــﻮد ﺗﻘﺮ ﺎً ﻋﻠﻰ اﻟﻘﺮص اﻟﻤﺮﻛﺰي اﻟﻜﺜ ﻒ . وﻣﻊ وﺟﻮد ﻣﺎدة ﻣﺎﺻـﺔ داﺋﻤًﺎ ﺑـ ﻧـﻮاة ا ﺠـﺮة اﻟﻨﺸـﻄﺔ وﺑﻴﻨﻨــﺎ ﻧﺠ ـﺢ اﻟﻔﺮﻳﻖ ﰲ اﻟﺘﻘﺎط اﻟﺘﺪﻓﻖ اﻟﱰاﻛﻤــﻲ ﻧﺤــﻮ ﻧــﻮاة ا ﺠﺮة اﻟﻨﺸـﻄﺔ . ﻋـﻼوة ﻋﲆ ذﻟـﻚ، ﻓﻘـﺪ أوﺿـﺢ ﻓﺮﻳﻖ اﻟﺒﺤﺚ أﻳﻀًﺎ اﻵﻟﻴﺔ اﻟﻔﻴﺰﻳﺎﺋﻴﺔ ا ﺴ ﺆوﻟﺔ ﻋـﻦ ﺗﺤﻔﻴﺰ ﺗﺮاﻛﻢ اﻟﻐﺎز وﻗـﺪ أﻇﻬــﺮ ﻗــﺮص اﻟﻐــﺎز ا ﺮﺻــﻮد ﻗـﻮة ﺟﺎذﺑﻴ ـﺔ ﻛﺒ ة ﻟﺪرﺟﺔ أﻧﻪ ﻻ ﻳﻤﻜﻦ ﺗﺤﻤﻠﻬـــﺎ ﺑ ﺎﻟﻀـــﻐﻂ ا ﺤﺴـﻮب ﻣ ـﻦ ﺣﺮﻛ ـﺔ ﻗﺮص اﻟﻐﺎز وﻋﻨﺪﻣﺎ ﺗﻨﺸﺄ ﻫﺬه اﻟﺤﺎﻟﺔ ﻳﻨﻬﺎر ﻗﺮص اﻟﻐﺎز ﺗﺤﺖ ﺛﻘﻠﻪ ﻣﺸﻜﻼ ﻫﻴﺎﻛﻞ ﻣﻌﻘﺪة وﻳﺼـﺒﺢ ﻏ ﻗﺎدر ﻋـﲆ اﻟﺤﻔـﺎظ ﻋﲆ ﺣﺮﻛـﺔ ﻣﺴـﺘﻘﺮة ﰲ ﻣﺮﻛـﺰ ا ﺠــﺮة وﻧﺘﻴﺠــﺔ ﻟــﺬﻟﻚ، ﻳﺴــﻘﻂ اﻟﻐــﺎز ـﺑــ ﴪﻋﺔ ﻧﺤ ـﻮ اﻟﺜﻘ ـﺐ اﻷﺳﻮد ا ﺮﻛﺰي . ﻟ ﻘﺪ ﻛﺸﻒ ﺎ ﻣﺮﺻﺪ أ ﻋﻦ ﻫﺬه اﻟﻈﺎﻫﺮة اﻟﻔﻴﺰﻳﺎﺋﻴﺔ ا ﻌﺮوﻓـﺔ ﺑﺎﺳـﻢ ﻋـﺪم " اﺳ ـﺘﻘﺮار اﻟﺠﺎذﺑﻴ ـﺔ ﰲ " ﻗﻠﺐ ا ﺠﺮة ﺑﺎﻹﺿﺎﻓﺔ إﱃ ذﻟﻚ ﻓﻘﺪ ﺳـﺎﻫﻤﺖ ﻫـﺬه اﻟﺪراﺳﺔ ﺑﺸﻜﻞ ﻛﺒـ ﰲ ﺗﻌﺰﻳــﺰ اﻟﻔﻬــﻢ اﻟﻜﻤــﻲ ــــــ ﻟﺘﺪﻓﻘﺎت اﻟﻐﺎز ﺣﻮل ﻧﻮاة ا ﺠـﺮة اﻟﻨﺸـﻄﺔ . ﻳﻤﻜﻦ ﺣﺴﺎب ﻣﻌﺪل اﻟﱰاﻛﻢ اﻟﺬي ﻳﺘﻢ ﻋﻨـﺪه إﻣﺪاد اﻟﺜﻘﺐ اﻷﺳﻮد ﺑﺎﻟ ﻐﺎز ﻣﻦ ﻛﺜﺎﻓﺔ اﻟﻐـﺎز ا ﺮﺻﻮد وﴎﻋﺔ ﺗﺪﻓﻖ ﻣﺎدة اﻟﱰاﻛﻢ . ﻣﻦ ا ﺜ ﻟﻠﺪﻫﺸﺔ أن ﻫﺬا ا ﻌﺪل ﻳﺰﻳﺪ 30 ﻣﺮة ﻋﻤﺎ ﻫﻮ ﻣﻄﻠﻮب ﻻﺳﺘﺪاﻣﺔ ﻧﺸﺎط ﻫﺬه ا ﻟﻨﻮاة ا ﺠﺮﻳﺔ اﻟﻨﺸﻄﺔ . ﺑﻤﻌﻨﻰ آﺧﺮ ﻣﻌﻈﻢ اﻟﺘـﺪﻓﻖ اﻟﱰاﻛﻤﻲ ﻋﲆ ﻣﻘﻴﺎس ﺳﻨﺔ ﺿـﻮ ﺋﻴﺔ واﺣـﺪة ﺣﻮل ﻣﺮﻛﺰ ا ﺠﺮة ﻟﻢ ﻳﺴ ﻬﻢ ﰲ ﻧﻤـﻮ اﻟﺜﻘـﺐ ـــ اﻷﺳﻮد ﻓﺄﻳﻦ ذﻫﺐ ﻫﺬا اﻟﻔﺎﺋﺾ ﻣـﻦ اﻟﻐـﺎز؟ ﺗﻜﺸﻒ ﻫﺬه اﻟﺪراﺳﺔ أﻳﻀ ﺎً ﻫﺬا اﻟﻠﻐﺰ ﺣﻞ ﻋﻦ وﻫﻮ ﻋﻤﻠﻴﺎت رﺻﺪ ﻋﺎﻟﻴﺔ اﻟﺤﺴﺎﺳﻴﺔ ﻟﺠﻤﻴﻊ ﻏﺎزات اﻟﻄﻮر ﻣﻊ اﻟﺘـﺪﻓﻘﺎت اﻟﺨﺎرﺟـﺔ ﻣـﻦ ﻧﻮاة ا ﺠﺮة اﻟﻨﺸﻄﺔ اﻟﺘﻲ اﻛﺘﺸﻔﻬﺎ ﻣﺮﺻﺪ أ ﺎ ﺑﻜﻞ ﺳﻬﻮﻟﻪ . ﻛﺸﻒ اﻟﺘﺤﻠﻴﻞ اﻟﻜﻤﻲ أن ﻣﻌﻈﻢ اﻟﻐﺎز اﻟـﺬي ﺗﺪﻓﻖ ﻧﺤﻮ اﻟﺜﻘﺐ اﻷﺳﻮد ﺗﻢ ﻃﺮده ﻛﺘﺪﻓﻘﺎت ذرﻳﺔ أو ﺟﺰﻳﺌﻴﺔ وﻣﻊ ذﻟﻚ، وﻧﻈﺮًا ﻟﺴ ـ ﺮﻋﺎﺗﻬﺎ ــ اﻟﺒﻄﻴﺌﺔ ﻟﻢ ﺗـﺘﻤﻜﻦ ﻣـﻦ اﻟﻬـﺮوب ﻣـﻦ اﻟ ﺠﺎذﺑﻴـﺔ اﻟﻜﺎﻣﻨﺔ ﻟ ﻠﺜﻘـﺐ اﻷﺳـﻮد ﻓﻌــﺎدت ﰲ اﻟﻨﻬﺎ ﻳــﺔ إﱃ ﻗﺮص اﻟﻐﺎز وﻫﻨﺎك ﺗﻤﺖ إﻋــﺎدة ﺗــﺪوﻳﺮﻫﺎ ﻣــﺮة أﺧـﺮى ﰲ ﺷـﻜﻞ ﺗ ـﺪﻓﻖ ﺗﺮاﻛﻤﻲ ﺑﺎﺗﺠـﺎه اﻟﺜﻘـﺐ اﻷﺳﻮد ﻳﺸـﺒﻪ اﻟﻨـﺎﻓﻮر ة وﺑــﺬﻟﻚ ﺗــﻢ اﺳــﺘﻜﻤﺎل ﻋﻤﻠﻴﺔ إﻋﺎدة ﺗﺪوﻳﺮ اﻟﻐﺎز اﻟﺮاﺋﻌﺔ ﰲ ﻣﺮﻛﺰ ا ﺠـﺮة . ﻓﻴﻤﺎ ﻳﺘﻌﻠـﻖ ﺑﺈﻧﺠـﺎزات ﻫ ـﺬه اﻟﺪراﺳ ـﺔ، ﻳﻘ ـﻮل ﺗﺎﻛﻮﻣــــﺎ إﻳﺰوﻣــــﻲ : » اﻛﺘﺸــﺎف اﻟﺘــﺪﻓﻘﺎت ا ﱰاﻛﻤــﺔ واﻟﺘــﺪﻓﻘﺎ ت اﻟﺨﺎرﺟﻴـﺔ ﰲ ﻣﻨﻄﻘــﺔ ﻻ ﺗﺒﻌﺪ ﺳﻮى ﺑﻀﻊ ﺳﻨﻮات ﺿــﻮﺋﻴﺔ ﺣــﻮل اﻟﺜﻘــﺐ اﻷﺳﻮد اﻟﻔﺎﺋﻖ ذو اﻟﻨﻤـﻮ اﻟﻨ ﺸﻂ ﺧﺎﺻـﺔ ﰲ اﻟﻐـﺎز ﻣﺘﻌﺪد ا ﺮاﺣﻞ وﺣﺘ ﻰ إن ﻛﺸــﻒ ﻏﻤــﻮض آﻟﻴــﺔ اﻟــﱰاﻛﻢ ﻧﻔﺴــﻬﺎ ﻫــﻲ اﻧﺠـﺎز ﻫﺎﺋ ـﻞ ﻳﺦ ﰲ ﺗـﺎر أﺑﺤﺎث اﻟﺜﻘﻮب اﻟﺴـﻮداء اﻟﻬﺎﺋﻠــﺔ و ﻳﺆﻛــﺪ ﻋــﲆ أﻫﻤﻴــﺔ ﻫــﺬا اﻹﻧﺠــﺎز اﺗﻄﻠﻊ إﱃ و ﻧﺤﻮ ا ﺴﺘﻘﺒﻞ وﻳﻮاﺻﻞ أﻳﻀًﺎ ﻗـﺎﺋﻼً :» ﻟﻜـﻲ ﻧﻔﻬـﻢ ﺑﺸـﻜﻞ ﺷﺎﻣﻞ ﻧﻤﻮ اﻟﺜﻘﻮب اﻟﺴﻮداء ﻓﺎﺋﻘﺔ اﻟﻜﺘﻠـﺔ ﰲ اﻟﺘﺎرﻳﺦ اﻟﻜـﻮﻧﻲ، ﻧﺤﺘـﺎج إﱃ دراﺳـﺔ أﻧـﻮاع ﻣﺨﺘﻠﻔﺔ ﻣﻦ اﻟﺜﻘ ﻮب اﻟﺴﻮداء ﻓﺎﺋﻘـﺔ اﻟﻜﺘﻠـﺔ ا ﻮﺟـﻮدة ﰲ أﻣــﺎﻛﻦ أﺑﻌ ـﺪ . وﻫــﺬا ﻳﺘﻄﻠــﺐ ﻋﻤﻠﻴﺎت رﺻﺪ ﻋﺎﻟﻴﺔ اﻟﺪﻗﺔ وﻋﺎﻟﻴﺔ اﻟﺤﺴﺎﺳﻴﺔ وﻟﺪﻳﻨﺎ ﺗﻮﻗﻌﺎت ﻛﺒـ ة ﺰﻳـﺪ ﻣـﻦ اﺳـﺘﺨﺪام ﻣﺮﺻـﺪ أ ـﺎ وﻣﻘـﺎﻳﻴﺲ اﻟﺘـﺪاﺧﻞ اﻟﺮادﻳـﻮي اﻟﻘﺎدﻣﺔ ﰲ اﻟﺠﻴﻞ اﻟﻘﺎدم . - ﻳﻨﺎﻳﺮ ﻓﺒﺮﺍﻳﺮ 2 0 2 4