Ukuhlaziywa kwe-Spectral yomthala okhanyayo i-JADES-GS-z14-0 okusekelwe ekubonweni okwenziwe ngoJanuwari 2024 kwembule i-redshift engu-14.32 okuwenza ube umthala okude kakhulu owaziwayo (umthala okude kakhulu owawaziwa ngokuthi i-JADES-GS-z13-0 endaweni ebomvu i-redshift kwe-z = 13.2). Yakhiwa endaweni yonke yokuqala cishe eminyakeni eyizigidi ezingu-290 ngemva kwe-Big Bang. Inani elikhulu lokukhanya kwenkanyezi lisikisela ukuthi kukhulu futhi kungaphezu kweminyaka engu-1,600 yokukhanya ububanzi ngosayizi. Umthala onjalo okhanyayo, omkhulu nomkhulu endaweni yonke yakuqala ekuntweleni kokusa kwe-cosmic udelela ukuqonda kwamanje ukwakheka komthala. Izinkanyezi zokuqala endaweni yonke kwakuyizinkanyezi ze-Pop III ezine-zero-metal noma ezinensimbi ephansi kakhulu. Kodwa-ke, ucwaningo lwezakhiwo ze-infrared zomthala we-JADES-GS-z14-0 lwembula ukuba khona komoyampilo okusho ukuthi ukunotha kwensimbi okusho ukuthi izizukulwane zezinkanyezi ezinkulu zase ziqedile izifundo zazo zokuphila kusukela ekuzalweni kuya ekuqhumeni kwe-supernova cishe eminyakeni eyizigidi ezingu-290 endaweni yokuqala. Ngakho, izici zalo mthala ziyangqubuzana nokuqonda kwamanje ukwakheka komthala endaweni yonke yokuqala.
Umkhathi wakudala kakhulu, eminyakeni engaba ngu-380,000 ngemva kwe-Big Bang, wawugcwele amagesi ane-ioned futhi wawungabonakali ngokuphelele ngenxa yokusakazwa kwama-photon ngama-electron amahhala. Lokhu kwalandelwa inkathi yokungathathi hlangothi yendawo yonke yokuqala eyathatha iminyaka engaba izigidi ezingu-400. Kule nkathi, indawo yonke yayingathathi hlangothi futhi isobala. Ukukhanya kokuqala kwavela endaweni yonke kuba sobala, kwaba bomvu kwashintshelwa ebangeni le-microwave ngenxa yokunwetshwa, futhi manje sekubonakala njenge-Cosmic Microwave Background (CMB). Ngenxa yokuthi indawo yonke yayigcwele amagesi angathathi hlangothi, asikho isignali yokubona eyakhishwa (yingakho ibizwa ngokuthi i-dark age). Izinto ezingezona i-ionized azikhiphi ukukhanya yingakho kunzima ekutadisheni indawo yonke yokuqala yenkathi engathathi hlangothi. Kodwa-ke, imisebe ye-microwave engu-21 cm ubude (ihambisana no-1420 MHz) ekhishwa i-cosmic hydrogen ebandayo, engathathi hlangothi phakathi nale nkathi ngenxa yoshintsho lwe-hyperfine ukusuka ku-parallel spin ukuya kwi-anti-parallel spin ezinzile inikeza amathuba kwizazi zezinkanyezi. Le misebe ye-microwave engu-21 cm izoshintshwa ngokubomvu lapho ifika emhlabeni futhi izobonwa kumaza angama-200MHz kuya ku-10 MHz njengamaza omsakazo. I REACH (I-Radio Experiment for the Analysis of Cosmic Hydrogen) Ukuhlola kuhloswe ukuthola ulayini ongatholakali kalula ongu-21-cm ku-Cosmic Hydrogen.
Inkathi ye-reionization kwaba inkathi elandelayo emlandweni wendawo yonke yakuqala eyathatha cishe iminyaka eyizigidi ezingu-400 ngemva kwe-Big Bang yaya eminyakeni eyi-1 bhiliyoni. Amagesi aphinde a-ionized ngenxa yamandla aphezulu emisebe ye-UV ekhishwa izinkanyezi zakuqala ezinamandla. Ukwakhiwa kwemithala nama-quasars kwaqala kule nkathi. Izibani zalesi sikhathi zibomvu zishintshelwe kububanzi obubomvu ne-infrared. Izifundo ze-Huble deep field zaziyisiqalo esisha ekutadisheni indawo yonke yakuqala nokho ububanzi bayo bokuthwebula izibani zakuqala babunomkhawulo. Kwakudingeka i-infrared observatory esekelwe emkhathini. I-JWST igxile kakhulu kwi-infrared astronomy ukuze ukufunda umkhathi wokuqala.
I-Telescope ye-James Webb Space (I-JWST) yethulwa mhla zingama-25 kuZibandlela wezi-2021. Ngemva kwalokho, i-tt yafakwa emzileni oseduze nendawo ye-Sun-Earth L2 Lagrange engaba yizigidi ezingu-1.5 km ukusuka emhlabeni. Iqale ukusebenza ngokugcwele ngoJulayi 2022. Isebenzisa amathuluzi abalulekile esayensi ebhodini afana ne-NIRCam (Near Infrared Camera), i-NIRSpec (Near Infrared Spectrograph), i-MIRI (Mid-Infrared Instrument), i-JWST icinga amasignali abonakalayo/e-infrared avela ezinkanyezini zakuqala nemithala. kwakhiwa endaweni yonke ukuze kuqondwe kangcono ukwakheka nokuziphendukela kwemithala kanye nokwakheka kwezinkanyezi nezinhlelo zamaplanethi. Eminyakeni emibili edlule, kukhiqize imiphumela ethokozisayo ekuhloleni ukusa kwe-cosmic (okungukuthi, inkathi eminyakeni eyizigidi ezingamakhulu ambalwa okuqala ngemva kokuqhuma okukhulu lapho imithala yokuqala yazalwa khona).
Uhlelo lwe-JWST Advanced Deep Extragalactic Survey (JADES).
Lolu hlelo luhlose ukutadisha ukuvela komthala kusukela ekushintsheni okuphezulu okubomvu kuya ku-cosmic emini ngendlela ye-infrared imaging kanye ne-spectroscopy emikhakheni ejulile ye-GOODS-S kanye ne-GOODS-N.
Onyakeni wokuqala, abacwaningi be-JADES bathola amakhulukhulu emithala kusukela eminyakeni yokuqala eyizigidi ezingu-650 ngemva kokuqhuma okukhulu. Ekuqaleni kuka-2023, bathola umthala kudathasethi yabo ebonakala sengathi ishintshile ngokubomvu okungu-14 okusikisela ukuthi lokho kufanele kube umthala okude kakhulu kodwa wawukhanya kakhulu. Futhi, ibonakale iyingxenye yomunye umthala ngenxa yokuba seduze. Ngakho-ke, babone lokho kuzuza ngo-Okthoba 2023. Idatha entsha yasekela ukuthi ishintshile ngo-14. Kudingeka i-spectrum yalo mthala ukuze kuhlonzwe indawo ye-Lyman-alpha break ku-spectrum ukuze kulinganiswe ukushintsha okubomvu nokunquma ubudala.
I-Lyman-alpha iwumugqa wokuphuma kwe-spectral we-hydrogen ochungechungeni lwe-Lyman lapho ama-electron eshintsha esuka ku-n=2 ukuya ku-n=1. Iphuzu le-Lyman-alpha break ku-spectrum lihambisana nobude obuqashiwe (λukuphawula). Ukushintsha okubomvu (z) kungabalwa ngokwefomula z = (λukuphawula – λukuphumula) / λukuphumula
I-JADES-GS-z14-0 umthala
Ngokufanelekile, umthala uphinde wabonwa ngoJanuwari 2024 kusetshenziswa i-NIRCam (Near Infrared Camera) kanye ne-NIRSpec (Near Infrared Spectrograph). Ukuhlaziywa kwe-Spectral kunikeze ubufakazi obucacile bokuthi umthala ubuku-redshift engu-14.32, okuwenza umthala okude kakhulu owaziwayo (irekhodi lomthala elikude kakhulu langaphambilini (JADES-GS-z13-0 at the redshift of z = 13.2). Waqanjwa ngokuthi i-JADES -GS-z14-0, umthala okhanyayo osebangeni leminyaka yokukhanya eyizigidi eziyizinkulungwane eziyi-13.5 Ngaphezu kwalokho, yayingaphezu kweminyaka engu-1,600 yokukhanya ububanzi eyayiphakamisa ukuthi izinkanyezi ezincane ziwumthombo wokukhanya kwawo Akulindelekile ukuthi umthala okhona ngaphansi kweminyaka eyizigidi ezingu-300 ngemva kwe-Big Bang ube nezakhiwo ezinjalo.
Kwakunezinye izimanga ezazilindelwe.
Abacwaningi bakwazile ukuthola i-JADES-GS-z14-0 kumaza amade amaza besebenzisa i-MIRI (Mid-Infrared Instrument). Lokhu bekusho ukuthwebula ukukhishwa kwebanga lokukhanya okubonakalayo kulo mthala okuye kwashintshwa ngokubomvu ukuze kungabi kude kumathuluzi aseduze ne-infrared. Ukuhlaziywa kwembula ubukhona bomoya-mpilo we-ionized obonisa i-stellar metallicity ephezulu. Lokhu kungenzeka kuphela lapho izizukulwane eziningi zezinkanyezi seziyiphile inkambo yazo yokuphila.
Izinkanyezi zokuqala endaweni yonke zinensimbi eyiziro noma zinensimbi ephansi kakhulu. Abizwa ngezinkanyezi ze-Pop III noma izinkanyezi ze-Population III. Izinkanyezi zensimbi ephansi ziyizinkanyezi ze-Pop II. Izinkanyezi ezisencane zinensimbi ephezulu futhi zibizwa ngokuthi “izinkanyezi ze-Pop I” noma izinkanyezi zensimbi yelanga. Ngokuqhathaniswa ne-metallicity ephezulu engu-1.4%, ilanga liyinkanyezi yakamuva. Ku-astronomy, noma iyiphi into esindayo kune-helium ibhekwa njengensimbi. Amakhemikhali angewona ama-metal njengomoya-mpilo, i-nitrogen njll ayizinsimbi esimweni se-cosmological. Izinkanyezi zithola insimbi inothiswa esizukulwaneni ngasinye kulandela umcimbi we-supernova. Ukwanda kokuqukethwe kwensimbi ezinkanyezini kubonisa ubudala obuncane.
Uma kubhekwa iminyaka yomthala i-JADES-GS-z14-0 ingaphansi kweminyaka eyizigidi ezingu-300 ngemva kwe-Big Bang, izinkanyezi kulo mthala kufanele kube izinkanyezi ze-Pop III ezinokuqukethwe okuyi-zero-metal. Kodwa-ke, i-MIRI ye-JWST yathola ukuba khona komoyampilo.
Uma kubhekwa lokhu okuphawulwe ngenhla nokutholwe, izici zomthala wendawo yonke wakuqala i-JADES-GS-z14-0 azihambisani nokuqonda kwamanje ukwakheka komthala. Kungenzeka kanjani ukuthi umthala onezici ezinjalo uqanjwe ukuthi waba eminyakeni eyizigidi ezingu-290 ngemva kwe-Bing Bang? Kungenzeka ukuthi imithala eminingi enjalo ingase itholakale esikhathini esizayo. Mhlawumbe izinhlobonhlobo zemithala zazikhona e-Cosmic Dawn.
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References:
- Carniani, S., et al. 2024. Ukuqinisekiswa kwe-Spectroscopic kwemithala emibili ekhanyayo endaweni ebomvu engu-14. Nature (2024). Ishicilelwe 24 July 2024. DOI: https://doi.org/10.1038/s41586-024-07860-9 . Shicilela ngaphambili ku-axRiv. Ihanjiswe ngomhla ka-28 Meyi 2024. DOI: https://doi.org/10.48550/arXiv.2405.18485
- Helton JM, et al 2024. Ukuthola i-JWST/MIRI photometric ku-7.7 μm we-stellar continuum nokuphuma kwe-nebular kumthala oku-z>14. Shicilela ngaphambili ku-axRiv. Ihanjiswe ngomhla ka-28 Meyi 2024. DOI: https://doi.org/10.48550/arXiv.2405.18462
- I-NASA James Webb Space Telescope. Amaphuzu avelele asekuqaleni - I-James Webb Space Telescope ye-NASA Ithola I-Galaxy Eyaziwa Kakhulu. Kuthunyelwe ngomhla ka-30 Meyi 2024. Itholakala e- https://webbtelescope.org/contents/early-highlights/nasas-james-webb-space-telescope-finds-most-distant-known-galaxy
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