Nearly all black holes come in one of dual sizes: stellar mass black holes that import adult to a few dozen times a mass of a object or supermassive black holes trimming from a million to several billion times a sun’s mass. Astronomers trust that medium-sized black holes between these dual extremes exist, though justification has been tough to come by, with roughly a half-dozen possibilities described so far.
A group led by astronomers during a University of Maryland and NASA’s Goddard Space Flight Center has found justification for a new intermediate-mass black hole about 5,000 times a mass of a sun. The find adds one some-more claimant to a list of intensity medium-sized black holes, while strengthening a box that these objects do exist. The group reported a commentary in a Sep 21, 2015 online book of Astrophysical Journal Letters.
The outcome follows adult on a identical anticipating by some of a same scientists, regulating a same technique, published in Aug 2014. While a prior investigate accurately totalled a black hole weighing 400 times a mass of a object regulating information from NASA’s Rossi X-ray Timing Explorer (RXTE) satellite, a stream investigate used information from a European Space Agency’s XMM-Newton satellite.
“This outcome provides support to a thought that black holes exist on all distance scales. When we report something for a initial time, there is always some doubt,” pronounced lead author Dheeraj Pasham, a postdoctoral associate during a Joint Space-Science Institute, a investigate partnership between UMD’s Departments of Astronomy and Physics and NASA Goddard. “Identifying a second claimant with a opposite instrument puts weight behind both commentary and gives us certainty in a technique.”
The new intermediate-mass black hole candidate, famous as NGC1313X-1, is personal as an ultraluminous X-ray source, and as such is among a brightest X-ray sources in a circuitously universe. It has proven tough to explain accurately because ultraluminous X-ray sources are so bright, however. Some astronomers think that they are intermediate-mass black holes actively sketch in matter, producing large amounts of attrition and X-ray deviation in a process.
Against this backdrop of rambling X-ray fireworks combined by NGC1313X-1, Pasham and his colleagues identified dual repeating flares, any flashing during an scarcely solid frequency. One flashed about 27.6 times per notation and a other about 17.4 times per minute. Comparing these dual rates yields a scarcely ideal 3:2 ratio. Pasham and his colleagues also found this 3:2 ratio in M82X-1, a black hole they identified in Aug 2014, nonetheless a altogether magnitude of flashing was many aloft in M82X-1.
Although astronomers are not nonetheless certain what causes these solid flashes, a participation of a clockwork 3:2 ratio appears to be a common underline of stellar mass black holes and presumably intermediate-mass black holes as well. The flashes are many expected caused by activity tighten to a black hole, where impassioned sobriety keeps all surrounding matter on a really parsimonious leash, Pasham said.
The 3:2 ratios can also produce an accurate magnitude of a black hole’s mass. Smaller black holes will peep during a aloft frequency, while incomparable black holes will peep reduction often.
“To make an analogy with acoustic instruments, if we suppose that stellar mass black holes are a violin and supermassive black holes are a double bass, afterwards intermediate-mass black holes are a violoncello,” pronounced co-author Francesco Tombesi, an partner investigate scientist in UMD’s Department of Astronomy who has a corner appointment during NASA Goddard around a Center for Research and Exploration in Space Science and Technology.
Pasham and Tombesi wish that identifying ultraluminous X-ray sources that vaunt a pivotal 3:2 flashing ratio will produce many some-more intermediate-mass black hole possibilities in a nearby future.
“Our process is quite empirical, it’s not reliant on models. That’s because it’s so strong,” Pasham explained. “We don’t know what causes these oscillations, though they seem to be reliable, during slightest in stellar mass black holes.”
NASA skeleton to launch a new X-ray telescope, a Neutron Star Interior Composition Explorer (NICER), in 2016. Pasham has already identified several intensity intermediate-mass black hole possibilities that he hopes to try with NICER.
“Observing time is during a premium, so we need to build a box with an determined process and a list of possibilities a process can request to,” Pasham explained. “With this result, we are in a good position to pierce brazen and make some-more sparkling discoveries.”