Kusho ukuthini nge-astrophysics yenuzi?
I-astrophysics yenuzi iyigatsha lesayensi elifunda izinqubo zenuzi ezenzeka endaweni yonke nokuthi zakha kanjani, ziguqula kanjani, futhi zisabalalisa kanjani izinto zasemkhathini. Nakuba i-astrophysics ngokuvamile ibhekana nezinto zasemkhathini—njengezinkanyezi, amaplanethi, ama-nebulae, kanye nemithala—i-astrophysics yenuzi iqokomisa “imishini” esebenza ngaphakathi kwayo: ukusabela kwenuzi, ukubola kwemisebe, kanye nokusebenzisana kwezinhlayiya ezinamandla aphezulu okunquma ukuvela kwezinkanyezi kanye nomsuka wezinto zamakhemikhali.
Empilweni yansuku zonke, siyazi i-nucleus ye-athomu njengesikhungo se-athomu, esakhiwe ngama-proton nama-neutron. Emkhathini , la ma-nuclei awahlali nje lapho; asabela ezindaweni ezinokushisa okukhulu kanye nokucindezela. Enkabeni yenkanyezi, isibonelo, amazinga okushisa afinyelela ezigidini kuya ezigidini zamadigri. Lezi zimo zivumela ama-nuclei e-athomu ukuthi ashayisane futhi adlule ekuhlanganisweni kwenuzi, ahlanganise ama-nuclei alula abe yizinzima ngenkathi ekhulula amandla. Lawa mandla yiwo enza izinkanyezi zikhanye futhi "yifektri" eyinhloko yokwakheka kwezinto endaweni yonke.
Kungani i-astrophysics yenuzi ibalulekile?
I-astrophysics yenuzi iphendula imibuzo eminingana emikhulu yesayensi. Okokuqala: izakhi zamakhemikhali zivelaphi? Izinto ezifana nekhabhoni emizimbeni yethu, umoya-mpilo esiwuphefumulayo, ngisho negolide elisebucwebeni aziveli nje emoyeni omncane. Zidalwa ngochungechunge lokusabela kwenuzi ezinkanyezini kanye nezehlakalo ezinkulu ze-cosmic, bese zisakazeka esikhaleni esiphakathi kwezinkanyezi ngemimoya yezinkanyezi noma ukuqhuma kwe-supernova . Okwesibili: izinkanyezi ziphila futhi zife kanjani? Umjikelezo wokuphila kwenkanyezi unqunywa kakhulu "uphethiloli" wenuzi otholakala enkabeni yayo nokuthi yiziphi izenzo ezibusayo esigabeni esithile. Okwesithathu: siyihlola kanjani imithetho yefiziksi ngaphansi kwezimo ezimbi kakhulu? Izinkanyezi ze-neutron ezifana nezimo zinobukhulu obukhulu kakhulu, okwenza kube amalabhorethri emvelo okuhlola imibono yezinto ezisemandleni amakhulu.
Imiqondo eyisisekelo: ukuhlanganiswa, ukubola, kanye nokubanjwa kwezinhlayiya
I-astrophysics yenuzi iqala ngezinqubo ezintathu eziyinhloko.
1. Ukuhlanganiswa kwe-nuclear: ukuhlanganiswa kwe-nuclei ekhanyayo ibe yi-nuclei esindayo. Isibonelo esaziwa kakhulu ukuguqulwa kwe-hydrogen ibe yi-helium ezinkanyezini ezifana neLanga. Ukuhlanganiswa kukhipha amandla ngoba isisindo esiphelele semikhiqizo sincane kancane kunesisindo se-reactants; lo mehluko wesisindo uguqulwa ube amandla ngokusho kwesibalo \(E = mc^2\).
2. Ukubola kwemisebe: ama-nuclei angazinzile aguquka abe amanye ama-nuclei ngokukhipha izinhlayiya noma imisebe. Lokhu kubola kubalulekile ezimweni ezahlukene, njengokusebenza njengomthombo wokushisa kwangaphakathi kwezinye izinto zasezulwini kanye "newashi" lendawo yonke ekunqumeni ubudala.
3. Ukubanjwa kwezinhlayiya: isibonelo, ukubanjwa kwama-neutron noma ama-proton yi-nucleus. Le nqubo ibalulekile ekwakhekeni kwezinto ezisindayo, ikakhulukazi lapho ama-neutron eningi futhi etholakala isikhathi esifushane.
Lezi zinqubo ezintathu zenzeka ngamazinga athonywa izinga lokushisa, ubuningi, ukwakheka kwezinto, kanye namathuba okusabela. Yilapho idatha yefiziksi yenuzi—njengezingxenye zokusabela kanye nokuphila okuyingxenye—iba khona ebalulekile.
I-astrophysics yenuzi ngaphakathi kwezinkanyezi: kusukela ekushiseni kwe-hydrogen kuya ensimbini
Izinkanyezi zithola amandla ngokusabela kochungechunge lwemiphumela yenuzi evame ukubizwa ngokuthi isigaba "sokusha", yize sihlukile ekushisweni ngamakhemikhali. Ukulandelana kwezigaba kuncike kubunzima benkanyezi.
– Ukusha kwe-hydrogen: Ezinkanyezini ezifana neLanga, i-hydrogen ihlangana ukuze yakhe i-helium ngokuyinhloko ngochungechunge lwe-proton-proton. Ezinkanyezini ezinkulu nezishisayo, umjikelezo we-CNO (carbon-nitrogen-oxygen) uyabusa; izakhi C, N, kanye ne-O zisebenza njengezinto ezibangela ukwakheka kwezinto.
– Ukushiswa kwe-Helium: Njengoba i-hydrogen enkabeni iphela, i-core iyancipha futhi ishise, okuvumela i-helium ukuthi ihlangane ngenqubo ye-triple-alpha ukuze yakhe ikhabhoni. Kulokhu, izakhi ezifana ne-oxygen nazo zingakheka.
– Izigaba ezithuthukile ezinkanyezini ezinkulu: Izinkanyezi ezinkulu zingaqhubeka nokuhlanganisa izakhi ezisindayo: ikhabhoni, i-neon, i-oxygen, ngisho ne-silicon. Lezi zigaba zikhiqiza ama-core asinda kakhulu, ekugcineni asondele ensimbini.
Kungani insimbi ivame ukubizwa ngokuthi umkhawulo? Ngoba ukuhlanganiswa kwama-nuclei okusindayo kunensimbi akusawakhiphi amandla, kodwa kunalokho kuyawadinga. Ngenxa yalokho, lapho umongo wenkanyezi enkulu ugcwele izakhi ezifana nensimbi, "injini" yamandla okuhlanganisa ayisebenzi. Kuleli qophelo, inkanyezi enkulu iseduze nokuwa kwamandla adonsela phansi, okungaholela ku-supernova.
Ama-supernova nokuzalwa kwezinto ezisindayo
Imicimbi ye-supernova iyisenzakalo esikhulu ku-astrophysics yenuzi. Lapho umongo wenkanyezi enkulu udilika, kwenzeka ukuqhuma okukhulu. Ngaphansi kwalezi zimo ezimbi kakhulu, kwenzeka i-neutron flux enamandla, okuvumela izakhi ezisinda kakhulu kunensimbi ukuthi zakheke ngokubamba i-neutron.
Ngokuvamile, kunezindlela ezimbili zokwakheka kwezinto ezisindayo:
– Inqubo ye-s (ukubanjwa kwe-neutron okuhamba kancane): ukubanjwa kwe-neutron kwenzeka kancane kakhulu kunokubola kwe-beta. Le nqubo ngokuvamile yenzeka ezinkanyezini ezinkulu ezibomvu (isb., izinkanyezi esigabeni se-AGB) futhi ikhiqiza izinto ezithile ezifana ne-strontium, i-barium, kanye ne-lead.
– Inqubo ye-r (ukubanjwa kwe-neutron okusheshayo): ukubanjwa kwe-neutron kwenzeka ngokushesha kakhulu kunokubola kwe-beta. Le nqubo idinga indawo ecebile kakhulu nge-neutron. Ngaphezu kwe-supernovae, ukuhlangana kwezinkanyezi ze-neutron manje sekuqashelwa njengomthombo omkhulu wenqubo ye-r, okukhiqiza izinto ezifana negolide, i-platinum, nezinye izinto ezisindayo.
Ukutholakala kwamagagasi adonsela phansi avela ekuhlanganeni kwezinkanyezi ze-neutron kanye nokubonwa kwe-kilonovae kuqinisa umqondo wokuthi izakhi ezisindayo "zingakhiqizwa" ezenzakalweni ezinjalo. Lokhu kubonisa indlela i-astrophysics yenuzi exhumanisa ngayo inkolelo-mbono, ukubonwa, kanye nokuhlolwa endabeni eyodwa yendawo yonke.
Indima yezinkanyezi ze-neutron, imisebe ye-cosmic, kanye ne-neutrinos
Ngaphandle kwezinkanyezi ezivamile, izinto eziyingozi kakhulu njengezinkanyezi ze-neutron nazo ziyizihloko ezibalulekile. Izinkanyezi ze-neutron ziyizinsalela ze-supernova eziminyene kakhulu; ithisipuni lezinto zazo lingasinda izigidigidi zamathani. Lapho, ukusebenzisana kwenuzi kuhilela izimo zezinto ngobuningi okunzima ukuziphinda elabhorethri. I-astrophysics yenuzi ifunda nokusabela oqweqweni lwezinkanyezi ze-neutron, njengalezo ezenzeka lapho izinto ezivela enkanyezini ehambisanayo ziwela (ukwanda), okubangela ukuqhuma kwe-X-ray.
Okwamanje, imisebe ye-cosmic—izinhlayiya ezinamandla kakhulu ezihamba emkhathini—zingangqubuzana nemimoya yeplanethi noma izinto eziphakathi kwezinkanyezi futhi zibangele ukuqhekeka, zihlukanise ama-nuclei abe yizinto ezilula njenge-lithium, i-beryllium, ne-boron. Lokhu kuchaza ukuthi kungani ezinye izinto ezilula zingavamile kakhulu ekuhlanganisweni kwezinkanyezi kodwa noma kunjalo zenzeka emvelweni.
Ama-neutrino nawo abaluleke kakhulu. Lezi zinhlayiya azihlangani kahle nezinto, kodwa zikhiqizwa ngobuningi obukhulu ezingxenyeni zezinkanyezi ikakhulukazi ngesikhathi se-supernovae. Ukutholwa kwama-neutrino avela kuma-supernovae (njenge-SN 1987A) kunikeza ubufakazi obuqondile bezinqubo zenuzi kanye namandla enuzi angenakubonwa ngokukhanya kuphela.
Ososayensi bayicwaninga kanjani?
I-astrophysics yenuzi iyinsimu exube kakhulu imikhakha eyahlukene. Izindlela zayo zifaka:
1. Ukuqaphelwa kwezinkanyezi: I-Spectroscopy isetshenziselwa ukuhlonza izakhi ezinkanyezini nasema-nebulae ngemigqa ye-spectral. Ubuningi bezakhi bunikeza izinkomba zezinqubo zenuzi ezenzekayo.
2. Ukuhlolwa kwe-physics yenuzi: Elabhorethri, ososayensi balinganisa ingxenye ehlukene yokusabela emandleni ahlobene nezimo zezinkanyezi. Inselele iwukuthi ukusabela ezinkanyezini kuvame ukwenzeka emandleni aphansi ngamathuba aphansi, ngakho-ke ukuhlolwa kudinga izinto zokuthola ezibucayi kakhulu nezindawo ezikhethekile.
3. Ukulingisa ngekhompyutha: Ngenxa yokuthi izinqubo eziningi zenzeka ngaphansi kwezimo ezimbi kakhulu futhi zihilela amanethiwekhi amakhulu okusabela, amamodeli ezinombolo asetshenziselwa ukulingisa ukuvela kwezinkanyezi, ama-supernovae, kanye nokwakheka kwezinto.
4. Ama-Astroparticles: Ukubonwa kwama-neutrinos, imisebe ye-gamma, kanye namagagasi adonsela phansi kugcwalisa ulwazi oluvela ekukhanyeni okubonakalayo, okwakha inkathi "yezinkanyezi eziningi".
Isiphetho
I-astrophysics yenuzi iwucwaningo lokuthi ukusabela kwenuzi kunika amandla kanjani izinkanyezi, kubangele izehlakalo zezulu ezibhubhisayo, futhi kwakha izakhi zamakhemikhali ezakha umhlaba osizungezile. Kusukela ekuhlanganisweni kwe-hydrogen eLangeni kuya ekuqhumeni kwe-supernova kanye nokuhlangana kwezinkanyezi ze-neutron ezikhiqiza izakhi ezisindayo, konke kuyingxenye yendaba efanayo: indawo yonke yavela ngezinqubo zenuzi. Ukuqonda i-astrophysics yenuzi kusho ukuqonda imvelaphi yezinto, umlando wezinkanyezi, kanye nezinqubo eziyisisekelo ezenza indawo yonke ibe yilokho eyikho namuhla.
Uma ufisa, ngingenza inguqulo ethandwa kakhulu yalesi sihloko (ulimi olulula) noma inguqulo yezemfundo (enefomula, izibonelo zokusabela, kanye nezinkomba zemiqondo efana nochungechunge lwe-proton-proton, i-triple-alpha, kanye nenqubo ye-s/r ngokuningiliziwe).
