Cim lub cev xilethi-aus tuaj yeem ua rau tsis meej pem. Tsuas yog cov hnub qub muaj qhov pom tseeb, qhov loj, qhov luminosity thiab lwm yam tsis muaj. Peb yuav sim daws qhov kawg. Lub luminosity ntawm cov hnub qub yog dab tsi? Nws puas muaj dab tsi ua nrog lawv qhov pom kev nyob rau hmo ntuj? Lub luminosity ntawm lub hnub yog dab tsi?
Nature of stars
hnub qub yog lub cev loj heev uas tawm lub teeb. Lawv yog tsim los ntawm gases thiab hmoov av, raws li ib tug tshwm sim ntawm gravitational compression. Sab hauv cov hnub qub yog lub hauv paus ntom ntom uas muaj cov tshuaj tiv thaiv nuclear. Lawv ua kom cov hnub qub ci. Cov yam ntxwv tseem ceeb ntawm cov luminaries yog cov spectrum, qhov loj me, ci ntsa iab, luminosity, sab hauv cov qauv. Tag nrho cov kev ntsuas no nyob ntawm qhov loj ntawm ib lub hnub qub thiab nws cov tshuaj muaj pes tsawg leeg.
Lub ntsiab "constructors" ntawm lub ntiaj teb no yog helium thiab hydrogen. Nyob rau hauv ib qho me me txheeb ze rau lawv, carbon, oxygen thiab hlau (manganese, silicon, hlau) yuav muaj. Cov hnub qub hluas muaj qhov loj tshaj plaws ntawm hydrogen thiab helium, nrog rau lub sij hawm lawv cov proportions txo, muab txoj kev rau lwm yam.
Wocov cheeb tsam sab hauv ntawm lub hnub qub, ib puag ncig yog "kub". Qhov kub hauv lawv nce mus txog ntau lab kelvins. Muaj kev cuam tshuam tsis tu ncua uas hydrogen hloov mus rau helium. Ntawm qhov chaw, qhov kub thiab txias qis dua thiab tsuas yog nce mus txog ob peb txhiab kelvins.
Lub luminosity ntawm cov hnub qub yog dab tsi?
Fusion cov tshuaj tiv thaiv hauv cov hnub qub yog nrog los ntawm kev tawm dag zog. Luminosity kuj yog hu ua lub cev kom muaj nuj nqis uas qhia tau meej npaum li cas lub zog ntawm lub cev xilethi-aus tsim nyob rau lub sijhawm.
Nws feem ntau tsis meej pem nrog lwm yam, xws li qhov ci ntawm cov hnub qub nyob rau hmo ntuj. Txawm li cas los xij, qhov ci ntsa iab lossis qhov pom tseeb yog qhov kwv yees tus yam ntxwv uas tsis ntsuas nyob rau hauv ib txoj kev. Nws muaj feem cuam tshuam nrog qhov kev ncua deb ntawm lub luminary los ntawm lub ntiaj teb thiab piav qhia tsuas yog tias lub hnub qub pom zoo nyob rau saum ntuj. Qhov tsawg dua tus naj npawb ntawm tus nqi no, qhov loj dua nws qhov pom kev ci ntsa iab.
Tsis zoo li nws, lub luminosity ntawm cov hnub qub yog lub hom phiaj parameter. Nws tsis yog nyob ntawm seb tus neeg soj ntsuam nyob qhov twg. Qhov no yog tus yam ntxwv ntawm lub hnub qub uas txiav txim siab nws lub zog lub zog. Nws tuaj yeem hloov pauv nyob rau lub sijhawm sib txawv ntawm kev hloov pauv ntawm lub cev xilethi-aus.
kwv yees li luminosity, tab sis tsis zoo ib yam, yog qhov loj kawg nkaus. Nws qhia txog qhov ci ntawm lub hnub qub, pom rau tus neeg soj ntsuam ntawm qhov deb ntawm 10 parsecs lossis 32.62 lub teeb xyoo. Nws yog feem ntau siv los xam cov luminosity ntawm cov hnub qub.
Kev txiav txim siab luminosity
Tus nqi zog uas lub cev xilethi-aus tso tawm yog txiav txim siab hauv watts (W), joules ib ob(J / s) lossis hauv ergs ib thib ob (erg / s). Muaj ntau txoj hauv kev los nrhiav qhov yuav tsum tau muaj.
Nws tuaj yeem suav tau yooj yim siv cov qauv L=0, 4(Ma -M) yog tias koj paub tus nqi tiag tiag ntawm lub hnub qub xav tau. Yog li, tsab ntawv Latin L sawv rau luminosity, tsab ntawv M yog qhov loj kawg nkaus, thiab Ma yog qhov loj ntawm lub hnub (4.83 Ma).
Lwm txoj kev muaj kev paub ntau ntxiv txog lub teeb pom kev zoo. Yog tias peb paub lub vojvoog (R) thiab qhov kub thiab txias (T ef ) ntawm nws qhov chaw, ces qhov luminosity tuaj yeem txiav txim siab los ntawm cov mis L=4pR 2sT4ef. Lub Latin s nyob rau hauv cov ntaub ntawv no txhais tau hais tias ib tug ruaj khov lub cev kom muaj nuj nqis - lub Stefan-Boltzmann tas mus li.
Lub luminosity ntawm peb lub hnub yog 3.839 x 10 26 Watts. Rau qhov yooj yim thiab meej, cov kws tshawb fawb feem ntau piv cov luminosity ntawm lub cev cosmic nrog tus nqi no. Yog li, muaj cov khoom ntau txhiab lossis ntau lab lub sijhawm tsis muaj zog lossis muaj zog dua lub hnub.
hnub qub luminosity chav kawm
Yuav piv cov hnub qub rau ib leeg, astrophysicists siv cov kev faib tawm sib txawv. Lawv muab faib ua spectra, qhov ntau thiab tsawg, kub, thiab lwm yam. Tab sis feem ntau, rau daim duab tiav, ob peb yam ntxwv siv ib zaug.
Muaj qhov nruab nrab Harvard kev faib tawm raws li cov spectra emitted los ntawm luminaries. Nws siv cov ntawv Latin, txhua tus sib raug rau cov xim tshwj xeeb ntawm hluav taws xob (O-xiav, B - dawb-xiav, A - dawb, thiab lwm yam).
Hnub qub ntawm tib lub spectrum tuaj yeem muaj qhov sib txawvluminosity. Yog li ntawd, cov kws tshawb fawb tau tsim Yerk kev faib tawm, uas tseem yuav siv rau hauv tus lej no. Nws cais lawv los ntawm luminosity, raws li lawv qhov loj npaum li cas. Nyob rau tib lub sij hawm, txhua hom hnub qub yog muab tsis tau tsuas yog cov tsiaj ntawv ntawm lub spectrum, tab sis kuj cov zauv lub luag hauj lwm rau lub luminosity. Yog li, faib:
- hypergiants (0);
- brightest supergiants (Ia+);
- bright supergiants (Ia);
- normal supergiants (Ib);
- bright giants (II);
- ib txwm loj loj (III);
- subgiants (IV);
- dwarfs ntawm lub ntsiab ntu (V);
- subdwarfs (VI);
- dwarfs dawb (VII);
Qhov ntau dua qhov luminosity, qhov me me ntawm tus nqi tiag. Rau cov loj heev thiab supergiants, nws yog qhia nrog tus cim rho tawm.
Kev sib raug zoo ntawm tus nqi tiag, qhov kub thiab txias, spectrum, luminosity ntawm cov hnub qub yog qhia los ntawm daim duab Hertzsprung-Russell. Nws tau saws nyob rau hauv 1910. Daim duab qhia txog kev faib tawm Harvard thiab York thiab tso cai rau koj los txiav txim siab thiab faib cov luminaries ntau dua.
Qhov sib txawv hauv luminosity
Cov tsis muaj hnub qub sib cuam tshuam nrog ib leeg. Lub luminosity yog cuam tshuam los ntawm qhov kub ntawm lub hnub qub thiab nws qhov loj. Thiab lawv feem ntau nyob ntawm cov tshuaj muaj pes tsawg leeg ntawm lub hnub qub. Qhov loj ntawm lub hnub qub yuav ntau dua, qhov hnyav dua nws muaj (hnyav dua li hydrogen thiab helium).
Hypergiants thiab ntau yam supergiants muaj ntau tshaj plaws. Lawv yog cov hnub qub uas muaj zog tshaj plaws thiab ci ntsa iab tshaj plaws hauv lub qab ntuj khwb, tab sis tib lub sijhawm, lawv yog cov tsawg tshaj plaws. Dwarfs, ntawm qhov tsis sib xws, muaj qhov loj me me thiabluminosity, tab sis ua li 90% ntawm tag nrho cov hnub qub.
Lub hnub qub loj tshaj plaws tam sim no paub yog xiav hypergiant R136a1. Nws luminosity tshaj lub hnub ci ib los ntawm 8.7 lab lub sij hawm. Lub hnub qub hloov pauv hauv lub hnub qub Cygnus (P Cygnus) tshaj lub hnub nyob rau hauv luminosity los ntawm 630,000 lub sij hawm, thiab S Doradus tshaj qhov ntsuas no los ntawm 500,000 zaug. Ib lub hnub qub me tshaj plaws paub, 2MASS J0523-1403 muaj luminosity ntawm 0.00126 ntawm Lub Hnub.
