[KSCI] Korea Science Citation Index Service

http://dx.doi.org/10.5303/PKAS.2015.30.2.129

FLUX MONITORING OF 6.7 GHz METHANOL MASER TO SYSTEMATICALLY RESEARCH PERIODIC VARIATIONS USING THE HITACHI 32-m

SUGIYAMA, KOICHIRO (Center for Astronomy, Ibaraki University)
YONEKURA, YOSHINORI (Center for Astronomy, Ibaraki University)
MOTOGI, KAZUHITO (The Research Institute for Time Studies, Yamaguchi University)
SAITO, YU (College of Science, Ibaraki University)
FUJISAWA, KENTA (The Research Institute for Time Studies, Yamaguchi University)
ISHII, SHOTA (College of Science, Ibaraki University)
MOMOSE, MUNETAKE (College of Science, Ibaraki University)
HONMA, MAREKI (Mizusawa VLBI Observatory)
TAZAKI, FUMIE (Mizusawa VLBI Observatory)
TANAKA, KEI E.I. (Department of Astronomy, University of Florida, 211 Bryant Space Science Center)
HOSOKAWA, TAKASHI (Department of Physics and Research Center for the Early Universe, The University of Tokyo)
UCHIYAMA, MIZUHO (Institute of Astronomy, Graduate School of Science, The University of Tokyo)
INAYOSHI, KOHEI (Department of Astronomy, Columbia University)

Publication Information

Publications of The Korean Astronomical Society / v.30, no.2, 2015 , pp. 129-131 More about this Journal

Abstract

We have initiated single-dish monitoring observations of ~400 methanol maser sources at 6.7 GHz using the Hitachi 32-m radio telescope from December 2012 to systematically research periodic flux variations, which are observed in some methanol maser sources associated with high-mass (proto-)stars. In our monitoring, we have made daily monitoring, so that each source has been observed every nine days with an integration time of 5 min (typical $3{\sigma}$ detection sensitivities of 0.9 Jy). The monitoring observations help us statistically understand periodic flux variations with a period longer than 50 days. As an initial result, we present a new detection of periodic flux variations in the 6.7 GHz methanol maser source G 036.70+00.09. The period of the flux variations is ~53 days (~0.019 cycles $day^{-1}$ ), and seems to be stable over 9 cycles, at least until the middle of August 2014.

Keywords

Masers: methanol; Stars: formation; Stars: massive; Stars: variables;

Citations & Related Records

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