A YOUNG MASSIVE STELLAR POPULATION AROUND THE INTERMEDIATE-MASS BLACK HOLE ESO 243-49 HLX-1

作者：Farrell S A^*; Servillat M; Pforr J; Maccarone T J; Knigge C; Godet O; Maraston C; Webb N A; Barret D; Gosling A J; Belmont R; Wiersema K

来源：Astrophysical Journal Letters, 2012, 747(1): L13.

DOI：10.1088/2041-8205/747/1/L13

• accretion, accretion disks
• galaxies: interactions
• galaxies: star clusters: general
• globular clusters: general
• X-rays: binaries
• X-rays: individual (ESO 243-49 HLX-1)

We present Hubble Space Telescope and simultaneous Swift X-ray Telescope observations of the strongest candidate intermediate-mass black hole (IMBH) ESO 243-49 HLX-1. Fitting the spectral energy distribution from X-ray to near-infrared wavelengths showed that the broadband spectrum is not consistent with simple and irradiated disk models, but is well described by a model comprised of an irradiated accretion disk plus a similar to 10(6) M-circle dot stellar population. The age of the population cannot be uniquely constrained, with both young and old stellar populations allowed. However, the old solution requires excessive disk reprocessing and an extremely small disk, so we favor the young solution (similar to 13 Myr). In addition, the presence of dust lanes and the lack of any nuclear activity from X-ray observations of the host galaxy suggest that a gas-rich minor merger may have taken place less than similar to 200 Myr ago. Such a merger event would explain the presence of the IMBH and the young stellar population.

• 出版日期2012-3-1