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Title: SIGNATURE OF AN INTERMEDIATE-MASS BLACK HOLE IN THE CENTRAL MOLECULAR ZONE OF OUR GALAXY

Abstract

We mapped the high-velocity compact cloud CO–0.40–0.22 in 21 molecular lines in the 3 mm band using the Nobeyama Radio Observatory 45 m radio telescope. Eighteen lines were detected from CO–0.40–0.22. The map of each detected line shows that this cloud has a compact appearance (d ≃ 3 pc) and extremely broad velocity width (ΔV ≃ 100 km s{sup −1}). The mass and kinetic energy of CO–0.40–0.22 are estimated to be 10{sup 3.6} M{sub ⊙} and 10{sup 49.7} erg, respectively. The representative position–velocity map along the major axis shows that CO–0.40–0.22 consists of an intense region with a shallow velocity gradient and a less intense high-velocity wing. Here, we show that this kinematical structure can be attributed to a gravitational kick to the molecular cloud caused by an invisible compact object with a mass of ∼10{sup 5} M{sub ⊙}. Its compactness and the absence of counterparts at other wavelengths suggest that this massive object is an intermediate-mass black hole.

Authors:
;  [1]; ;  [2]
  1. Department of Physics, Institute of Science and Technology, Keio University, 3-14-1 Hiyoshi, Yokohama, Kanagawa 223-8522 (Japan)
  2. School of Fundamental Science and Technology, Graduate School of Science and Technology, Keio University, 3-14-1 Hiyoshi, Yokohama, Kanagawa 223-8522 (Japan)
Publication Date:
OSTI Identifier:
22518646
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal Letters; Journal Volume: 816; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; BLACK HOLES; CARBON MONOXIDE; CLOUDS; GALAXIES; GALAXY NUCLEI; KINETIC ENERGY; MASS; MOLECULES; RADIO TELESCOPES; VELOCITY; WAVELENGTHS; ZONES

Citation Formats

Oka, Tomoharu, Mizuno, Reiko, Miura, Kodai, and Takekawa, Shunya, E-mail: tomo@phys.keio.ac.jp. SIGNATURE OF AN INTERMEDIATE-MASS BLACK HOLE IN THE CENTRAL MOLECULAR ZONE OF OUR GALAXY. United States: N. p., 2016. Web. doi:10.3847/2041-8205/816/1/L7.
Oka, Tomoharu, Mizuno, Reiko, Miura, Kodai, & Takekawa, Shunya, E-mail: tomo@phys.keio.ac.jp. SIGNATURE OF AN INTERMEDIATE-MASS BLACK HOLE IN THE CENTRAL MOLECULAR ZONE OF OUR GALAXY. United States. doi:10.3847/2041-8205/816/1/L7.
Oka, Tomoharu, Mizuno, Reiko, Miura, Kodai, and Takekawa, Shunya, E-mail: tomo@phys.keio.ac.jp. Fri . "SIGNATURE OF AN INTERMEDIATE-MASS BLACK HOLE IN THE CENTRAL MOLECULAR ZONE OF OUR GALAXY". United States. doi:10.3847/2041-8205/816/1/L7.
@article{osti_22518646,
title = {SIGNATURE OF AN INTERMEDIATE-MASS BLACK HOLE IN THE CENTRAL MOLECULAR ZONE OF OUR GALAXY},
author = {Oka, Tomoharu and Mizuno, Reiko and Miura, Kodai and Takekawa, Shunya, E-mail: tomo@phys.keio.ac.jp},
abstractNote = {We mapped the high-velocity compact cloud CO–0.40–0.22 in 21 molecular lines in the 3 mm band using the Nobeyama Radio Observatory 45 m radio telescope. Eighteen lines were detected from CO–0.40–0.22. The map of each detected line shows that this cloud has a compact appearance (d ≃ 3 pc) and extremely broad velocity width (ΔV ≃ 100 km s{sup −1}). The mass and kinetic energy of CO–0.40–0.22 are estimated to be 10{sup 3.6} M{sub ⊙} and 10{sup 49.7} erg, respectively. The representative position–velocity map along the major axis shows that CO–0.40–0.22 consists of an intense region with a shallow velocity gradient and a less intense high-velocity wing. Here, we show that this kinematical structure can be attributed to a gravitational kick to the molecular cloud caused by an invisible compact object with a mass of ∼10{sup 5} M{sub ⊙}. Its compactness and the absence of counterparts at other wavelengths suggest that this massive object is an intermediate-mass black hole.},
doi = {10.3847/2041-8205/816/1/L7},
journal = {Astrophysical Journal Letters},
number = 1,
volume = 816,
place = {United States},
year = {Fri Jan 01 00:00:00 EST 2016},
month = {Fri Jan 01 00:00:00 EST 2016}
}
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