演講資訊

摘要：

There is growing evidence showing that, in addition to the stellar-mass and the central supermassive black holes, there is another class of black holes weighing in between the stellar-mass and supermassive, the so-called intermediate-mass black holes (IMBHs; 100 to a million solar masses). In this talk, I will present our recent results on the two ULXs, and the IMBH in the center of Mrk 59 (part of NGC 4861 complex) that was not resolved in previous X-ray observations. The IMBH’s location is coincident with a SDSS optical counterpart classified as galaxy. EVN observation also reveals a radio association within the region, indicating the presence of a jet. Using the fundamental plane relationship of accreting black holes, we estimate the central black hole mass to be around ten-thousand solar masses, that makes it fall in the range of IMBHs. A prominent HeII+other high-excitation lines associated with gas photo ionized by the X-ray source confirm its AGN nature, this is the very first AGN in the intermediate mass range found in a blue compact dwarf galaxy (the local analogue of high-redshift galaxies). Our discovery demonstrates that black holes in active compact dwarf galaxies indeed bridge the gap between supermassive and stellar-mass black holes and provide long-sought observational evidence that blue compact dwarf galaxies might truly be the building blocks of larger galaxies, which will shed light on understanding the growth of black holes and the formation of galaxies in the early Universe.