The James Webb Space Telescope has captured images of two early universe quasars, revealing the relationship between black holes and their host galaxies. The breakthrough suggests that the mass ratios observed in newer galaxies existed less than a billion years after the Big Bang.
Recent James Webb Space Telescope (JWST) observations of two quasars in the nascent universe have revealed important insights into the early relationship between black holes and their galaxies, which is consistent with mass ratios observed in the recent universe.
New images reveal for the first time the starlight of two massive galaxies hosting actively growing black holes called quasars less than a billion years after the Big Bang. These black holes are nearly a billion times the mass of our sun, while their host galaxies are nearly a hundred times our sun's mass, a ratio similar to that found in the recent universe. According to a recent research report published in Nature, the powerful combination of the Subaru Telescope's wide-field survey observations and JWST paves a new way to study the distant universe.
近年来，对巨型黑洞的观测引起了天文学家的关注。事件地平线望远镜（EHT）已经开始对星系中心的黑洞"影子"进行成像。2020年新物理学奖授予了银河系中心的恒星运动观测。虽然这种巨型黑洞的存在已经变得确凿无疑，但没有人知道它们的起源。
Astronomers report that billion-solar-mass black holes existed in the universe's first billion years - how could these black holes have grown so large when the universe was so young? Even more puzzling, observations of the local universe show a clear relationship between the mass of supermassive black holes and the larger galaxies in which they reside.星系和黑洞的大小完全不同，那么是黑洞先出现还是星系先出现呢？这是一个宇宙尺度上的"先有鸡还是先有蛋"的问题。
An international research team led by Peking University's Kavli Institute for Astronomy and Astrophysics (KIAA) Kavli Astrophysics Researcher Masafusa Onoue, Kavli Institute for Physics and Mathematics of the Universe (IPMU) researcher Ding Xuheng, and IPMU Professor John Silverman has set out to answer this question using the James Webb Space Telescope (JWST). The James Webb Space Telescope (JWST) is a 6.5-meter space telescope jointly developed by the National Aeronautics and Space Administration (NASA), the European Space Agency (ESA) and the Canadian Space Agency (CSA) and will be launched in December 2021.
Quasars are bright while their host galaxies are dim, which poses a challenge for researchers to detect the dim light of galaxies against the bright light of quasars, especially at long distances. "Searching for the host galaxies of quasars at redshift 6 is like wearing foggy glasses to find fireflies in a breathtaking fireworks show. The host galaxies are very dim and the image resolution is very limited, even by the Hubble Space Telescope, so uncovering their hidden beauty is a real challenge," said Xuheng Ding.
The research team used JWST to observe two quasars, namely HSCJ2236+0032 and HSCJ2255+0251, with redshifts of 6.40 and 6.34 respectively. The age of the universe at that time was approximately 860 million years. The two quasars were originally discovered through wide-field surveys of the 8.2-meter Subaru telescope, and so far, the research team has used the telescope to discover more than 160 quasars. These relatively low-brightness quasars are prime targets for measuring the properties of their host galaxies, and their successful detection represents the earliest detection of starlight in a quasar to date.
Images of the two quasars were taken with JWST's NIRCam instrument at infrared wavelengths of 3.56 and 1.50 microns, with the host galaxy becoming clearly visible after careful modeling and subtraction of glare from the accreting black hole. Stellar signatures of the host galaxy are also seen in the spectrum taken by JWST's NIRSpec for J2236+0032, further supporting the detection of the host galaxy. "I have been deeply involved in the Subaru high-redshift quasar survey since I was a PhD student at the National Astronomical Observatory of Japan. I am very proud that we successfully detected the starlight of high-redshift quasars using the Subaru telescope," said Masafusa Onoue.
Through observations, the research team found that the ratio of black hole mass to host galaxy mass is similar to the ratio of black hole mass to host galaxy mass in the modern universe. This result shows that the relationship between the black hole and the host galaxy was formed within the first billion years after the Big Bang. The research team will continue this study with a larger sample of distant quasars, aiming to further constrain the co-evolution history of black holes and their parent galaxies in cosmic time. These observations will constrain models of the coevolution of black holes and their parent galaxies.
Compiled source: ScitechDaily