Kumaphepha ashicilelwe kutshanje, abaphandi baqikelele ukuba izinga lokuwa kwe-supernova core kwi-Milky Way ibe yi-1.63 ± 0.46 iziganeko ngekhulu leminyaka. Ngoko ke, xa kunikwe isiganeko sokugqibela se-supernova, i-SN 1987A yabonwa kwiminyaka engama-35 eyadlulayo ngo-1987, isiganeko esilandelayo se-supernova kwi-Milky Way sinokulindeleka nangaliphi na ixesha kwixesha elizayo.
Ubomi benkwenkwezi kunye ne-supernova
Ngokwexesha eliziibhiliyoni zeminyaka, iinkwenkwezi ziphila ubomi bazo, ziyazalwa, ziguge kwaye ekugqibeleni zife ngokuqhuma kunye nokusasazeka kwezinto zeenkwenkwezi ziye kwindawo ephakathi kweenkwenkwezi njengothuli okanye ilifu.
Ubomi benkwenkwezi buqala kwi-nebula (ilifu lothuli, i-hydrogen, i-helium kunye nezinye iigesi ezifakwe kwi-ionized) xa ukuwa komxhuzulane welifu elikhulu kubangela i-protostar. Oku kuyaqhubeka nokukhula ngakumbi ngokukhula kwegesi kunye nothuli de kufikelelwe kubunzima bayo bokugqibela. Ubunzima bokugqibela benkwenkwezi bumisela ubomi bayo kunye noko kwenzeka kwinkwenkwezi ngexesha lobomi bayo.
Zonke iinkwenkwezi zifumana amandla azo kwi-nucleus fusion. Ukutsha kwamafutha enyukliya embindini kudala uxinzelelo olukhulu lwangaphandle ngenxa yobushushu obuphezulu obuphakathi. Oku kulinganisela amandla angaphakathi axhuzulayo. Ibhalansi iyaphazamiseka xa amafutha embindini ephela. Ubushushu buyehla, uxinzelelo lwangaphandle luyancipha. Ngenxa yoko, amandla axhuzulayo okuxinana kwangaphakathi ayalawula okunyanzela umongo ukuba unciphe kwaye udilike. Oko inkwenkwezi ekugqibeleni iphela emva kokudilika kuxhomekeke kubunzima benkwenkwezi. Kwimeko yeenkwenkwezi ezinkulu kakhulu, Xa umongo udilika ngexesha elifutshane, udala amaza amakhulu okutsha. Ukuqhuma okunamandla, okukhanyayo kubizwa ngokuba yi-supernova.
Esi siganeko seenkwenkwezi esidlulayo senzeka ngexesha lokugqibela lenkqubela phambili yenkwenkwezi kwaye sishiya intsalela ye-supernova. Ngokuxhomekeke kubunzima benkwenkwezi, intsalela inokuba yinkwenkwezi ye-neutron okanye umngxuma omnyama.
I-SN 1987A, i-supernova yokugqibela
Isiganeko sokugqibela se-supernova yayiyi-SN 1987A eyabonwa esibhakabhakeni esisezantsi kwiminyaka engama-35 eyadlulayo ngoFebruwari 1987. Yayisisiganeko sokuqala se-supernova esinjalo esibonakala ngamehlo enyama ukusukela kwiKepler's ngo-1604. Ifumaneka kwiLarge Magellanic Cloud ekufutshane ( umthala wesathelayithi weMilky Way), yayiyenye yeenkwenkwezi eziqhumayo ezikhanyayo ezibonwe kwiminyaka engaphezu kwama-400 ezazivutha ngamandla elanga elizizigidi ezili-100 kangangeenyanga ezininzi kwaye zanika ithuba elikhethekileyo lokufunda ngezigaba ngaphambi, ngexesha, nasemva kokufa kwenkwenkwezi.
Ukufundwa kwe-supernova kubalulekile
Ukufunda nge-supernova kuluncedo ngeendlela ezahlukeneyo ezifana nokulinganisa umgama esibhakabhakeni , ukuqonda ukwanda kwendalo kunye nohlobo lweenkwenkwezi njengeefektri zazo zonke izinto ezenza yonke into (kuquka nathi) efumaneka kwindalo iphela . Izinto ezinzima ezenziwe ngenxa yokudibana kwenyukliya (kwezinto ezikhaphukhaphu) embindini weenkwenkwezi kunye nezinto ezisandula ukwenziwa ngexesha lokuwa kwembindi zisasazwa kuyo yonke indawo ngexesha lokuqhuma kwe-supernova. Ii-supernova zidlala indima ebalulekileyo ekusasazeni izinto kwindalo iphela.
Ngelishwa, bekungekho thuba lininzi ngaphambili lokubona nokufunda ngokusondeleyo ukuqhuma kwe-supernova. Ukujonga ngokusondeleyo kunye nokufunda ukuqhuma kwe-supernova ngaphakathi kwegalaxy yethu yasekhaya iMilky Way kuya kuba yinto emangalisayo kuba uphando phantsi kwezo meko belungenakuze lwenziwe kwiilabhoratri eMhlabeni. Yiyo loo nto kubalulekile ukubhaqa i-supernova kwangoko nje ukuba iqale. Kodwa, umntu uza kwazi njani ukuba ukuqhuma kwe-supernova kuza kuqala? Ngaba kukho nayiphi na inkqubo yokulumkisa kwangethuba yokuthintela ukuqhuma kwe-supernova?
I-Neutrino, ibhakana yokudubula kwe-supernova
Ngasekupheleni kwekhondo lobomi, njengokuba inkwenkwezi iphuma kwizinto ezikhaphukhaphu njengezibaso zenyukliya edibanisayo eyinika amandla, umxhuzulane ongaphakathi uyongamela kwaye umaleko wangaphandle wenkwenkwezi uqalisa ukuwela ngaphakathi. Undoqo uqalisa ukuwohloka kwaye kwiimilliseconds ezimbalwa undoqo uye ucinezeleke kangangokuba ii-electron kunye neeprotons zidibana zenze ii-neutron kwaye i-neutrino ikhutshwe kwi-neutron nganye eyenziweyo.
Ii-neutrons ezenziwe ngolu hlobo zenza inkwenkwezi ye-proto-neutron ngaphakathi kwentliziyo apho yonke inkwenkwezi iwela phantsi kwentsimi enamandla yomxhuzulane ize ibuye umva. I-shock wave eveliswayo iyawa inkwenkwezi ishiya intsalela yodwa yomongo (inkwenkwezi ye-neutron okanye umngxuma omnyama ngokuxhomekeke kubunzima benkwenkwezi) kwaye yonke enye inxalenye yobunzima benkwenkwezi isasazeka iye kwindawo ephakathi kweenkwenkwezi.
Ukuqhuma okukhulu kwee -neutrinos eziveliswa kukuphuma kwe-core-collapse ukuya esibhakabhakeni ngaphandle kokuphazanyiswa ngenxa yokuba azisebenzisani nezinto. Malunga ne-99% yamandla okubopha adonsela phantsi aphuma njengee-neutrinos (ngaphambi kwee-photons ezivaleleke ebaleni) kwaye asebenza njengesibane sokuthintela ukuqhuma kwe-supernova. Ezi neutrinos zinokubanjwa emhlabeni ziindawo zokujonga ze-neutrino ezithi zona zisebenze njengesilumkiso sasekuqaleni sokubonwa okunokwenzeka kokuqhuma kwe-supernova kungekudala.
I-neutrinos ebalekayo ikwabonelela ngefestile eyodwa kwizehlo ezigqithisileyo ngaphakathi kwenkwenkwezi eqhumayo ezinokuba nefuthe ekuqondeni amandla asisiseko kunye namasuntswana asisiseko.
Inkqubo yesilumkiso yangethuba yeSupernova (SNEW)
Ngexesha lokugqibela lokubonwa kwe-core-collapse supernova (SN1987A), into eyenzekayo yabonwa ngeso lenyama. I-neutrinos zabhaqwa zizichongi ezibini ze-Cherenkov zamanzi, i-Kamiokande-II kunye ne-Irvine-MichiganBrookhaven (IMB) yovavanyo oluye lwaqaphela iziganeko ze-neutrino ze-19. Nangona kunjalo, ukufunyaniswa kwe-neutrinos kunokusebenza njengebhakana okanye i-alam yokuthintela ukubonwa kwe-supernova. Ngenxa yoko, iindawo ezahlukeneyo zokujonga izinto kunye nezazi ngeenkwenkwezi azikwazanga ukusebenza ngexesha ukuze zifunde kwaye ziqokelele idatha.
Ukususela ngo-1987, i-astronomy ye-neutrino iye yahamba phambili kakhulu. Ngoku, inkqubo yesilumkiso se-supernova i-SNWatch isendaweni ecwangciselwe ukukhalisa i-alam kwiingcali kunye nemibutho efanelekileyo malunga nokubonwa kwe-supernova enokwenzeka. Kwaye, kukho uthungelwano lwe-neutrino observatories kwihlabathi liphela, ebizwa ngokuba yi-Supernova Early Warning System (SNEWS) edibanisa imiqondiso yokuphucula ukuzithemba ekubhaqweni. Nawuphi na umsebenzi wesiqhelo uyaziswa kwiseva ephakathi ye-SNEWS ngabachongi ngabanye. Ngaphaya koko, i-SNEWS iye yaphuculwa ukuya kwi-SNEWS 2.0 kutshanje evelisa izilumkiso zokuzithemba okuphantsi.
I-Supernova ekufuphi kwi-Milkyway
Ii-Neutrino observatories ezisasazeke kwihlabathi liphela zijolise ekufumaneni okokuqala ii-neutrinos ezibangelwa kukudilika kweenkwenkwezi ezikwigalaksi yethu yasekhaya . Impumelelo yazo ke ngoko, ixhomekeke kakhulu kwisantya sokudilika kwe-supernova core kwiMilky Way.
Kumaphepha ashicilelwe kutshanje, abaphandi baqikelele izinga lokuwa kwe-supernova core kwi-Milky Way ukuba ibe yi-1.63 ± 0.46 iziganeko kwiminyaka eyi-100; malunga ne-supernovae enye ukuya kwezimbini ngenkulungwane. Ngaphaya koko, uqikelelo lubonisa ukuba ixesha eliphakathi kwe-core fallpse supernova kwiMilky Way linokuba phakathi kwama-47 ukuya kuma-85 eminyaka.
Ngenxa yeso siganeko sokugqibela se-supernova, i-SN 1987A yabonwa kwiminyaka engama-35 eyadlulayo, isiganeko esilandelayo se-supernova kwiMilky Way sinokulindelwa nangaliphi na ixesha kwixesha elizayo. Njengoko ii-neutrino observatories zidibene ukuze zibone ukuqhuma kwangethuba kunye neNkqubo ye-Supernova Early Warning (SNEW) ephuculweyo, izazinzulu ziya kuba kwindawo yokujonga ngokusondeleyo iziganeko ezilandelayo ezigqithisileyo ezinxulumene nokuqhuma kwe-supernova kwenkwenkwezi efayo. Esi iya kuba sisiganeko esibalulekileyo kunye nethuba elikhethekileyo lokufunda izigaba ngaphambi, ngexesha, nasemva kokufa kwenkwenkwezi ukuze kuqondwe ngcono indalo iphela.
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