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 “svarthol mass-gap”, this compact object could be either a massive neutron stjörnu or the lightest svarthol 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 svarthol in future, this would be the first “pulsar – svarthol system” known.
Þegar eldsneyti klárast verður kjarnorkusamruni í stjörnur stöðvast og engin orka er til að hita efni til að koma jafnvægi á innra þyngdarkraftinn. Þar af leiðandi hrynur kjarninn undir eigin þyngdarafl og skilur eftir sig þétta remanent. This the end of the star. The dead star could white dwarf or neutron star or svarthol depending upon mass of the original star. Stars between 8 to 20 solar masses end up as neutron stars (NSs) while more heavier stars become svarthol (BHs).
Hámarksmassi á nifteindastjörnur is about 2.2 solar masses while svarthol formed at the end of stellar life cycle are usually of more than 5 solar masses. This mass-gap between the lightest black home (viz. 5 M⊙) and the heaviest neutron stjörnu (viz. 2.2 M⊙) er vísað til „massabils fyrir svarthol“.
Compact objects in “svarthol mass-gap”
Compact objects falling in mass-gap (between 2.2 to 5 solar masses) are not commonly encountered nor are well understood. Some compact objects observed in þyngdarbylgja events are in the mass-gap region. One such recent instance was discovery of a compact mass of 2.6 solar masses on 14 August 2019 in the merger event GW190814 which resulted in black home of final black hole about 25 solar masses.
Samþykkir hlutir í massabili í „tvíundarkerfis“ myndun
Scientists 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 “svarthol mass-gap”, this compact object could be either a massive neutron stjörnu or the lightest svarthol or some unknown star variant.
Nákvæmt eðli þessa líkama er enn ekki ákveðið.
Hins vegar, það sem er áhugaverðara er að ólíkt sambærilegum þéttum líkama sem fannst í samrunaviðburðinum GW 190814, finnst þessi þétti líkami í tvíkerfismyndun sem fylgifiskur sérvitringa tvíundar millisekúndna pulsar.
If this compact body in binary formation with the pulsar is determined to be a svarthol in future, this would be the first “pulsar – svarthol system” known. This is what pulsar astronomers are looking for decades.
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Tilvísanir:
- LIGO. Fréttatilkynning - LIGO-Virgo finnur leyndardómshlut í „Mass Gap“. Birt 23. júní 2020. Fæst á https://www.ligo.caltech.edu/LA/news/ligo20200623
- E. Barr o.fl., A pulsar in a binary with a compact object in massabil milli nifte stjörnu og svarthol Science, 19. janúar 2024. DOI: https://doi.org/10.1126/science.adg3005 Forprentun https://doi.org/10.48550/arXiv.2401.09872
- Fishbach M., 2024. Leyndardómur í „fjöldabilinu“. VÍSINDI. 18. janúar 2024. 383. árgangur, 6680. bls. 259-260. DOI: https://doi.org/10.1126/science.adn1869
- SARAO 2024. Fréttir – Léttasta svartholið eða þyngsta nifteindastjarnan? MeerKAT afhjúpar dularfullan hlut á mörkum svarthola og nifteindastjarna. Sent 18. janúar 2024. Fæst á 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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