Searching for an Intermediate Mass Black Hole in the Blue Compact Dwarf galaxy MRK 996

Abstract

The possibility is explored that accretion on an intermediate mass black hole contributes to the ionisation of the interstellar medium of the Compact Blue Dwarf galaxy MRK996. Chandra observations set tight upper limits (99.7 per cent confidence level) in both the X-ray luminosity of the posited AGN, Lx(2-10keV)<3e40erg/s, and the black hole mass, <1e4/λMsolar, where λ, is the Eddington ratio. The X-ray luminosity upper limit is insufficient to explain the high ionisation line [OIV]25.89μm, which is observed in the mid-infrared spectrum of the MRK996 and is proposed as evidence for AGN activity. This indicates that shocks associated with supernovae explosions and winds of young stars must be responsible for this line. It is also found that the properties of the diffuse X-ray emission of MRK996 are consistent with this scenario, thereby providing direct evidence for shocks that heat the galaxy's interstellar medium and contribute to its ionisation.

Submitted to MNRAS

References in corpus (13)

• The synthesis of the cosmic X-ray background in the Chandra and XMM-Newton era
• Formation of Supermassive Black Holes by Direct Collapse in Pregalactic Halos
• Supermassive black hole formation during the assembly of pre-galactic discs
• A New Sample of Low-mass Black Holes in Active Galaxies
• The evolution of massive black hole seeds
• Emission-line Diagnostics of Low Metallicity AGN
• Precise Black Hole Masses From Megamaser Disks: Black Hole-Bulge Relations at Low Mass
• The Coincidence of Nuclear Star Clusters and Active Galactic Nuclei
• A new method for determining the sensitivity of X-ray imaging observations and the X-ray number counts
• The mass function of high redshift seed black holes
• Dynamical Constraints on The Masses of the Nuclear Star Cluster and Black Hole in the Late-Type Spiral Galaxy NGC 3621
• Low-Mass Seyfert 2 Galaxies in the Sloan Digital Sky Survey
• An Accreting Black Hole in the Nuclear Star Cluster of the Bulgeless Galaxy NGC 1042

Cited by in corpus (7)

• Intermediate-Mass Black Holes
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• The merging dwarf galaxy UM 448: chemodynamics of the ionized gas from VLT integral field spectroscopy
• $NuSTAR$ Observations of Four Nearby X-ray Faint AGN: Low Luminosity or Heavy Obscuration?
• An X-ray + Radio Search for Massive Black Holes in Blue Compact Dwarf Galaxies
• A Gemini/GMOS study of the physical conditions and kinematics of the blue compact dwarf galaxy Mrk 996
• Physical Origins of Outflowing Cold Clouds in Local Star-forming Dwarf Galaxies