Published January 1, 2015 | Version v1
Journal article

NO MICROWAVE FLARE OF SAGITTARIUS A* AROUND THE G2 PERIASTRON PASSING

  • 1. Institute of Space and Astronautical Science (ISAS), Japan Aerospace Exploration Agency, 3-1-1 Yoshinodai, Chuo-ku, Sagamihara, Kanagawa 252-5210 (Japan)
  • 2. Mizusawa VLBI Observatory, National Astronomical Observatory of Japan, 2-12, Hoshigaoka, Mizusawa, Oshu, Iwate 023-0861 (Japan)
  • 3. Center for Astronomy, Ibaraki University, 2-1-1 Bunkyo, Mito, Ibaraki 310-8512 (Japan)
  • 4. Division of Physics, Faculty of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8571 (Japan)
  • 5. Faculty of Engineering, Gifu University, 1-1, Yanagito, Gifu, Gifu 501-1193 (Japan)
  • 6. National Astronomical Observatory of Japan, 2-21-1, Osawa, Mitaka, Tokyo 181-8588 (Japan)
  • 7. Geospatial Information Authority of Japan, 1, Kitasato, Tsukuba 305-0811 (Japan)
  • 8. Department of Astronomy, the University of Tokyo, Bunkyo, Tokyo 113-0033 (Japan)
  • 9. Kashima Space Research Center, National Institute of Information and Communications Technology (NICT) 893-1 Hirai, Kashima, Ibaraki 314-8501 (Japan)

Description

In order to explore any change caused by the G2 cloud approaching, we have monitored the flux density of Sgr A* at 22 GHz from 2013 February to 2014 August with a sub-array of the Japanese Very Long Baseline Interferometry Network. The observation period included the expected periastron dates. The number of observation epochs was 283 days. We have observed no significant microwave enhancement of Sgr A* in the whole observation period. The average flux density in the period is S ν = 1.23 ± 0.33 Jy. The average is consistent with the usually observed flux density range of Sgr A* at 22 GHz

Availability note (English)

Available from http://dx.doi.org/10.1088/2041-8205/798/1/L6

Additional details

Identifiers

Publishing Information

Journal Title
Astrophysical Journal Letters
Journal Volume
798
Journal Issue
1
Journal Page Range
[4 p.]
ISSN
2041-8205

INIS

Country of Publication
United States
Country of Input or Organization
International Atomic Energy Agency (IAEA)
INIS RN
46070099
Subject category
S79: ASTROPHYSICS, COSMOLOGY AND ASTRONOMY;
Descriptors DEI
CLOUDS; FLUX DENSITY; GALAXIES; GALAXY NUCLEI; GHZ RANGE; INTERFEROMETRY; MICROWAVE RADIATION; MONITORS
Descriptors DEC
ELECTROMAGNETIC RADIATION; FREQUENCY RANGE; MEASURING INSTRUMENTS; RADIATIONS