skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: The black hole mass and the stellar ring in NGC 3706

Abstract

We determine the mass of the nuclear black hole (M) in NGC 3706, an early-type galaxy with a central surface brightness minimum arising from an apparent stellar ring, which is misaligned with respect to the galaxy's major axis at larger radii. We fit new HST/STIS and archival data with axisymmetric orbit models to determine M, mass-to-light ratio (Y {sub V}), and dark matter halo profile. The best-fit model parameters with 1σ uncertainties are M=(6.0{sub −0.9}{sup +0.7})×10{sup 8} M{sub ⊙} and Υ{sub V}=6.0±0.2 M{sub ⊙} L{sub ⊙,V}{sup −1} at an assumed distance of 46 Mpc. The models are inconsistent with no black hole at a significance of Δχ{sup 2} = 15.4 and require a dark matter halo to adequately fit the kinematic data, but the fits are consistent with a large range of plausible dark matter halo parameters. The ring is inconsistent with a population of co-rotating stars on circular orbits, which would produce a narrow line-of-sight velocity distribution (LOSVD). Instead, the ring's LOSVD has a small value of |V|/σ, the ratio of mean velocity to velocity dispersion. Based on the observed low |V|/σ, our orbit modeling, and a kinematic decomposition of the ring from the bulge, we conclude that themore » stellar ring contains stars that orbit in both directions. We consider potential origins for this unique feature, including multiple tidal disruptions of stellar clusters, a change in the gravitational potential from triaxial to axisymmetric, resonant capture and inclining of orbits by a binary black hole, and multiple mergers leading to gas being funneled to the center of the galaxy.« less

Authors:
;  [1]; ;  [2];  [3];  [4];  [5]
  1. Department of Astronomy, University of Michigan, 500 Church Street, Ann Arbor, MI 48109 (United States)
  2. Department of Astronomy, University of Texas, 1 University Station C1400, Austin, TX 78712 (United States)
  3. National Optical Astronomy Observatory, P.O. Box 26732, Tucson, AZ 85726 (United States)
  4. Universitäts-Sternwarte München, Ludwig-Maximilians-Universität, Scheinerstr. 1, D-81679 München (Germany)
  5. Institute for Advanced Study, Einstein Dr., Princeton, NJ 08540 (United States)
Publication Date:
OSTI Identifier:
22348096
Resource Type:
Journal Article
Journal Name:
Astrophysical Journal
Additional Journal Information:
Journal Volume: 781; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0004-637X
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; AXIAL SYMMETRY; BLACK HOLES; CAPTURE; DECOMPOSITION; DISPERSIONS; DISTANCE; DISTRIBUTION; GALAXIES; GALAXY NUCLEI; MASS; NONLUMINOUS MATTER; ORBITS; ORIGIN; SIMULATION; STARS; VELOCITY; VISIBLE RADIATION

Citation Formats

Gültekin, Kayhan, Richstone, Douglas O., Gebhardt, Karl, Kormendy, John, Lauer, Tod R., Bender, Ralf, and Tremaine, Scott. The black hole mass and the stellar ring in NGC 3706. United States: N. p., 2014. Web. doi:10.1088/0004-637X/781/2/112.
Gültekin, Kayhan, Richstone, Douglas O., Gebhardt, Karl, Kormendy, John, Lauer, Tod R., Bender, Ralf, & Tremaine, Scott. The black hole mass and the stellar ring in NGC 3706. United States. doi:10.1088/0004-637X/781/2/112.
Gültekin, Kayhan, Richstone, Douglas O., Gebhardt, Karl, Kormendy, John, Lauer, Tod R., Bender, Ralf, and Tremaine, Scott. Sat . "The black hole mass and the stellar ring in NGC 3706". United States. doi:10.1088/0004-637X/781/2/112.
@article{osti_22348096,
title = {The black hole mass and the stellar ring in NGC 3706},
author = {Gültekin, Kayhan and Richstone, Douglas O. and Gebhardt, Karl and Kormendy, John and Lauer, Tod R. and Bender, Ralf and Tremaine, Scott},
abstractNote = {We determine the mass of the nuclear black hole (M) in NGC 3706, an early-type galaxy with a central surface brightness minimum arising from an apparent stellar ring, which is misaligned with respect to the galaxy's major axis at larger radii. We fit new HST/STIS and archival data with axisymmetric orbit models to determine M, mass-to-light ratio (Y {sub V}), and dark matter halo profile. The best-fit model parameters with 1σ uncertainties are M=(6.0{sub −0.9}{sup +0.7})×10{sup 8} M{sub ⊙} and Υ{sub V}=6.0±0.2 M{sub ⊙} L{sub ⊙,V}{sup −1} at an assumed distance of 46 Mpc. The models are inconsistent with no black hole at a significance of Δχ{sup 2} = 15.4 and require a dark matter halo to adequately fit the kinematic data, but the fits are consistent with a large range of plausible dark matter halo parameters. The ring is inconsistent with a population of co-rotating stars on circular orbits, which would produce a narrow line-of-sight velocity distribution (LOSVD). Instead, the ring's LOSVD has a small value of |V|/σ, the ratio of mean velocity to velocity dispersion. Based on the observed low |V|/σ, our orbit modeling, and a kinematic decomposition of the ring from the bulge, we conclude that the stellar ring contains stars that orbit in both directions. We consider potential origins for this unique feature, including multiple tidal disruptions of stellar clusters, a change in the gravitational potential from triaxial to axisymmetric, resonant capture and inclining of orbits by a binary black hole, and multiple mergers leading to gas being funneled to the center of the galaxy.},
doi = {10.1088/0004-637X/781/2/112},
journal = {Astrophysical Journal},
issn = {0004-637X},
number = 2,
volume = 781,
place = {United States},
year = {2014},
month = {2}
}