相关论文: Monitoring observations of 6.7 GHz methanol masers

Discovery of periodic maser emission was an unexpected result from monitoring observations of methanol transitions in high-mass young stellar objects. We report on the detection of five new periodic sources from a monitoring program with…

We report the discovery of 6.7 GHz methanol maser periodic flares in four massive star forming regions and the updated light curve for the known periodic source G22.357+0.066. The observations were carried out with the Torun 32 m radio…

We present the results of a 5-year monitoring program of 42 sources targeted at 6.7 GHz methanol masers, conducted from March 2017 to October 2022 using the Irbene 32 and 16 meter radio telescopes. Sources were observed with irregular…

We report the discovery of periodic flares of 6.7GHz methanol maser in the young massive stellar object G22.357+0.066. The target was monitored in the methanol maser line over 20 months with the Torun 32m telescope. The emission was also…

Periodic flares of maser emission are thought to be induced either by variations of the seed photon flux in young binary systems or the pump rate regulated by stellar and accretion luminosities. We seek to study the variability of four…

Results of the long-term monitoring observations of the 6.7 GHz Class II methanol masers associated with the four high-mass star-forming regions by Hitachi 32-m radio telescope are presented. We detected periodic flux variability in…

An intensive monitoring program of 54 6.7-GHz methanol maser sources was carried out at the Hartebeesthoek Radio Astronomy Observatory from January 1999 to April 2003. The monitoring program was subsequently continued on 19 sources of…

6.7 GHz methanol maser emission from the well-studied star-forming region Cepheus A was monitored with the Torun 32 m radio telescope. We found synchronized and anticorrelated changes of the flux density of the two blueshifted and one…

Aims. We report the discovery of periodic maser variability of an unusual pattern in the high-mass young stellar object G26.598-0.024. Methods. A ten-year monitoring of the 6.7 GHz methanol maser was carried out with the Torun 32 m radio…

We report the detection of bursts of 6.7 GHz methanol maser emission in a high-mass star-forming region, G33.64-0.21. One of the spectral components of the maser in this source changed its flux density by 7 times that of the previous day,…

Context: Periodicity in 6.7 GHz methanol maser sources is a rare phenomenon that was discovered during long-term monitoring programmes. Understanding the underlying processes that lead to periodic variability might provide insights into the…

We have observed bursting variability of the 6.7 GHz methanol maser of G33.641-0.228. Five bursts were detected in the observation period of 294 days from 2009 to 2012. The typical burst is a large flux density rise in about one day…

Context. Class II methanol masers at 6.7 and 12.2 GHz occur close to high-mass young stellar objects (HMYSOs). When they are observed simultaneously, such studies may contribute to refining the characterisation of local physical conditions.…

We detected flaring flux variability that regularly occurred with the period of 23.9 days on a 6.7 GHz methanol maser emission at Vlsr = 25.30 km/s in G 014.23-00.50 through highly frequent monitoring using the Hitachi 32-m radio telescope.…

The 6.7 GHz methanol maser in a high-mass star-forming region G33.641$-$0.228 is known to exhibit burst-like flux variability due to an unknown mechanism. To investigate the burst mechanism, we conducted high-cadence flux and circular…

We have detected periodic flares of the 6.7 GHz methanol maser from an intermediate-mass star-forming region IRAS22198+6336. The maser was monitored daily in 2011, 2012, and 2013. Six flares were observed with a period of 34.6 days. The…

Context: Class II methanol masers at 6.7 GHz originate close to high-mass young stellar objects (HMYSOs). Their high sensitivity to local condition variations makes them a useful marker of the activity of the emerging massive stars. Aims:…

{The variability study of 6.7\,GHz methanol masers has become a useful way to improve our understanding of the physical conditions in high-mass star-forming regions.} {Based on the single-dish monitoring using the Irbene telescopes, we…

Methanol and water vapour masers are signposts of early stages of high-mass star formation but it is generally thought that due to different excitation processes they probe distinct parts of stellar environments. Here we present…

We present the results of a high sensitivity survey for 6.7 GHz methanol masers towards 22 GHz water maser using the 100 m Efflesberg telescope. A total of 89 sources were observed and 10 new methanol masers were detected. The new…