Skip to main content Accessibility help
×
Home

Long-term and highly frequent monitor of 6.7 GHz methanol masers to statistically research periodic flux variations around high-mass protostars using the Hitachi 32-m

  • Koichiro Sugiyama (a1) (a2), Y. Yonekura (a2), K. Motogi (a3), Y. Saito (a2), T. Yamaguchi (a4), M. Momose (a2) (a4), M. Honma (a5), T. Hirota (a1), M. Uchiyama (a6), N. Matsumoto (a1), K. Hachisuka (a5), K. Inayoshi (a7), K. E. I. Tanaka (a8), T. Hosokawa (a9) and K. Fujisawa (a10)...

Abstract

We initiated a long-term and highly frequent monitoring project toward 442 methanol masers at 6.7 GHz (Dec >−30 deg) using the Hitachi 32-m radio telescope in December 2012. The observations have been carried out daily, monitoring a spectrum of each source with intervals of 9–10 days. In September 2015, the number of the target sources and intervals were redesigned into 143 and 4–5 days, respectively. This monitoring provides us complete information on how many sources show periodic flux variations in high-mass star-forming regions, which have been detected in 20 sources with periods of 29.5–668 days so far (e.g., Goedhart et al. 2004). We have already obtained new detections of periodic flux variations in 31 methanol sources with periods of 22–409 days. These periodic flux variations must be a unique tool to investigate high-mass protostars themselves and their circumstellar structure on a very tiny spatial scale of 0.1–1 au.

Copyright

References

Hide All
Araya, E. D., Hofner, P., Goss, W. M., et al., 2010, ApJL, 717, L133
Breen, S. L., Fuller, G. A., Caswell, J. L., et al., 2015, MNRAS, 450, 4109
Goedhart, S., Gaylard, M. J., & van der Walt, D. J., 2004, MNRAS, 355, 553
Goedhart, S., Maswanganye, J. P., Gaylard, M. J., & van der Walt, D. J., 2014, MNRAS, 437, 1808
Hosokawa, T. & Omukai, K., 2009, ApJ, 691, 823
Inayoshi, K., Sugiyama, K., Hosokawa, T., Motogi, K., & Tanaka, K. E. I., 2013, ApJL, 769, L20
Lomb, N. R., 1976, Ap&SS, 39, 447
Parfenov, S. Y. & Sobolev, A. M., 2014, MNRAS, 444, 620
Scargle, J. D., 1982, ApJ, 263, 835
Sugiyama, K., Yonekura, Y., Motogi, K., et al., 2015, PKAS, 30, 129
Sugiyama, K., Nagase, K., Yonekura, Y., et al., 2017, PASJ, 69, 59
Szymczak, M., Wolak, P., & Bartkiewicz, A., 2015, MNRAS, 448, 2284
Szymczak, M., Olech, M., Wolak, P., Bartkiewicz, A., & Gawroński, M., 2016, MNRAS, 459, L56
van der Walt, D. J., 2011, AJ, 141, 152
van der Walt, D. J., Maswanganye, J. P., Etoka, S., Goedhart, S., & van den Heever, S. P., 2016, A&A, 588, A47
Yonekura, Y., Saito, Y., Sugiyama, K., et al., 2016, PASJ, 68, 74
MathJax
MathJax is a JavaScript display engine for mathematics. For more information see http://www.mathjax.org.

Keywords

Metrics

Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed