Cov kws tshawb fawb hnub qub tau tshaj tawm tias lawv tau pom ib yam khoom me me uas muaj li ntawm 2.35 lub cev hnyav ntawm lub hnub nyob rau hauv lub pawg NGC 1851 hauv peb lub tsev. galaxy Txoj Kev Milky Way. Vim tias qhov no nyob rau ntawm qhov kawg qis ntawm "dub qhov mass-gap ”, cov khoom no compact yuav yog ib tug loj neutron lub hnub qub los yog lightest dub qhov lossis qee lub hnub qub tsis paub variant. Qhov xwm txheej tseeb ntawm lub cev no tseem tsis tau txiav txim siab. Txawm li cas los xij, qhov nthuav ntau dua yog tias, tsis zoo li lub cev compact zoo sib xws pom hauv qhov kev sib koom ua ke GW190814, lub cev compact no pom nyob rau hauv binary system tsim ua tus khub ntawm pulsar. Yog tias lub cev compact no hauv binary tsim nrog pulsar tau txiav txim siab ua ib qho dub qhov yav tom ntej, qhov no yuav yog thawj "pulsar - dub qhov system” paub.
Thaum cov roj ntws tawm, nuclear fusion nyob rau hauv hnub qub nres thiab tsis muaj lub zog rau cov khoom siv cua sov kom sib npaug sab hauv lub zog ntawm lub ntiajteb txawj nqus. Yog li ntawd, cov tub ntxhais hluas ntog nyob rau hauv nws tus kheej lub ntiajteb txawj nqus, tawm hauv qab ib tug compact remanentQhov no yog qhov kawg ntawm lub hnub qub. Lub hnub qub tuag tuaj yeem dhau los ua lub hnub qub dawb lossis lub hnub qub neutron lossis ib qho dub qhov nyob ntawm seb lub hnub qub qub loj npaum li cas. Cov hnub qub uas muaj qhov hnyav ntawm 8 txog 20 lub hnub qub yuav dhau los ua cov hnub qub neutron (NSs) thaum cov hnub qub hnyav dua yuav dhau los ua dub qhov (BHs).
Qhov siab tshaj plaws ntawm neutron hnub qub yog hais txog 2.2 hnub ci huab cua thaum dub qhov tsim nyob rau thaum kawg ntawm lub neej ntawm lub hnub qub feem ntau yog ntau dua 5 lub hnub qub loj. Qhov sib txawv ntawm qhov dub sib dua tshaj plaws (viz. 5 M⊙) thiab qhov hnyav tshaj plaws neutron lub hnub qub (ib. 2.2 M⊙) yog hu ua "dub qhov loj-gap".
Compact khoom hauv "dub qhov loj-gap”
Cov khoom me me uas poob rau hauv qhov sib txawv ntawm qhov hnyav (ntawm 2.2 txog 5 lub hnub qub) tsis tshua pom thiab tsis nkag siab zoo. Qee cov khoom me me uas pom hauv gravitational yoj cov xwm txheej nyob rau hauv thaj chaw sib txawv no. Ib qho piv txwv tsis ntev los no yog kev tshawb pom ntawm qhov hnyav me me ntawm 2.6 lub hnub qub hnyav rau hnub tim 14 Lub Yim Hli 2019 hauv qhov kev sib koom ua ke GW190814 uas ua rau muaj qhov dub kawg ntawm kwv yees li 25 lub hnub qub hnyav.
Cov khoom sib xyaw ua ke hauv qhov sib txawv loj hauv "binary system" tsim
Cov kws tshawb fawb tsis ntev los no tau tshaj tawm txog kev tshawb pom ntawm cov khoom sib cog lus ntawm li 2.35 hnub ci hauv pawg globular NGC 1851 hauv peb. tsev galaxy Milky Way. Vim qhov no yog qhov kawg ntawm "dub qhov mass-gap ”, cov khoom no compact yuav yog ib tug loj neutron lub hnub qub los yog lightest dub qhov los yog qee qhov tsis paub lub hnub qub variant.
Qhov tseeb ntawm lub cev no tseem tsis tau txiav txim siab.
Txawm li cas los xij, qhov nthuav ntxiv yog tias, tsis zoo li lub cev me me zoo sib xws uas pom hauv qhov kev sib koom ua ke GW190814, lub cev me me no pom nyob rau hauv kev tsim binary system ua tus khub ntawm lub eccentric binary millisecond pulsar.
Yog hais tias lub cev compact no nyob rau hauv binary tsim nrog lub pulsar yog txiav txim siab los ua ib tug dub qhov yav tom ntej, qhov no yuav yog thawj "pulsar - dub qhov system” paub. Qhov no yog qhov pulsar astronomers tab tom nrhiav rau xyoo lawm.
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References:
- LIGO. Xov xwm tshaj tawm - LIGO-Virgo Nrhiav Tsis Paub Cov Khoom hauv "Pawg Gap". Tshaj tawm rau Lub Rau Hli 23, 2020. Muaj nyob ntawm https://www.ligo.caltech.edu/LA/news/ligo20200623
- E. Barr et al., Ib tug pulsar nyob rau hauv ib tug binary nrog ib tug compact khoom nyob rau hauv lub loj sib txawv ntawm neutron hnub qub thiab dub qhov Science, Lub ib hlis ntuj 19, 2024. DOI: https://doi.org/10.1126/science.adg3005 Ua ntej https://doi.org/10.48550/arXiv.2401.09872
- Fishbach M., 2024. Mystery in the “mass gap”. SCIENCE. 18 Jan 2024. Vol 383, Issue 6680. p. 259-260. DOI: https://doi.org/10.1126/science.adn1869
- SARAO 2024. Xov xwm - Lub qhov dub tshaj plaws lossis lub hnub qub neutron hnyav tshaj plaws? MeerKAT nthuav tawm cov khoom tsis meej ntawm tus ciam teb ntawm qhov dub thiab cov hnub qub neutron. Tshaj tawm 18 Lub Ib Hlis 2024. Muaj nyob ntawm https://www.sarao.ac.za/news/lightest-black-hole-or-heaviest-neutron-star-meerkat-uncovers-a-mysterious-object-at-the-boundary-between-black-holes-and-neutron-stars/
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![Pinterest](https://pinterest.com/pin/create/button/?url=https://www.scientificeuropean.co.uk/sciences/space/have-astronomers-discovered-the-first-pulsar-black-hole-binary-system/&media=https://www.scientificeuropean.co.uk/wp-content/uploads/2024/01/system-assuming-that-the-massive-companion-star-is-a-black-hole-scaled-1.jpeg&description=Astronomers have recently reported detection of such a compact object of about 2.35 solar masses in the globular cluster NGC 1851 in our home galaxy Milkyway. Because this is at the lower end of “black hole mass-gap", this compact object could be either a massive neutron star or the lightest black hole or some unknown star variant. The exact nature of this body is yet to be determined. However, what is more interesting is that, unlike the similar compact body detected in the merger event GW 190814, this compact body is found in binary system formation as the companion of a pulsar. If this compact body in binary formation with the pulsar is determined to be a black hole in future, this would be the first “pulsar - black hole system” known. ){kind=link}