60 citations · 558 across the 26 of their papers we have counts for
15 papers · 1 filter
Discovery of synchronized periodic variability of methanol maser features in G26.598-0.024
P. Wolak, M. Szymczak, A. Kobak +5
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…
Proper motion study of the 6.7 GHz methanol maser rings. I. A sample of sources with little variation
A. Bartkiewicz, A. Sanna, M. Szymczak +5
Methanol masers at 6.7~GHz are well-known signposts of high-mass star-forming regions. [...] We aim to understand the origin of the ring-like structures outlined by methanol maser…
Seven-year periodic variations in the methanol maser line displayed by the massive protostar IRAS 20216+4104
M. Szymczak, M. Durjasz, S. Goedhart +5
Aims: We report the discovery and analysis of a periodic methanol maser in the massive protostar IRAS 20216+4104. Methods: To obtain the light curve, we used the 6.7 GHz methanol m…
Molecular line search toward the flaring 6.7-GHz methanol masers of G24.33+0.13 and G359.6-0.243: rare maser transitions detected
Tiege McCarthy, Gabor Orosz, Simon Ellingsen +8
We have performed a molecular line search toward the flaring 6.7-GHz masers G24.33+0.13 and G359.62-0.24 using the Australia Telescope Compact Array. We present spectra of the 6.7-…
Observations of 12.2 GHz methanol masers towards northern high-mass protostellar objects
M. Durjasz, M. Szymczak, P. Wolak +1
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…
A search for the OH 6035 MHz line in high-mass star-forming regions
M. Szymczak, P. Wolak, A. Bartkiewicz +2
The excited states of OH masers detected in the environment of high-mass young stellar objects (HMYSOs) are important for improving our understanding of the physical conditions of…
Detection statistics of the RadioAstron AGN survey
Y. Y. Kovalev, N. S. Kardashev, K. V. Sokolovsky +57
The largest Key Science Program of the RadioAstron space VLBI mission is a survey of active galactic nuclei (AGN). The main goal of the survey is to measure and study the brightnes…
New evidence for Dicke's superradiance in the 6.7 GHz methanol spectral line in the interstellar medium
F. Rajabi, M. Houde, A. Bartkiewicz +3
We present new evidence for superradiance in the methanol 6.7 GHz spectral line for three different star-forming regions: S255IR-NIRS3, G24.329+0.144, and Cepheus A. Our analysis s…
Giant burst of methanol maser in S255IR-NIRS3
Marian Szymczak, Mateusz Olech, Paweł Wolak +2
Context: High-mass young stellar objects (HMYSOs) can undergo accretion episodes that strongly affect the star evolution, the dynamics of the disk, and its chemical evolution. Rece…
Monitoring observations of 6.7 GHz methanol masers
Marian Szymczak, Mateusz Olech, Rafał Sarniak +2
We report results of 6.7 GHz methanol maser monitoring of 139 star-forming sites with the Torun 32 m radio telescope from June 2009 to February 2013. The targets were observed at l…
Discovery of four periodic methanol masers and updated light curve for a further one
M. Szymczak, P. Wolak, A. Bartkiewicz
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…
6.7GHz methanol maser variability in Cepheus A
M. Szymczak, P. Wolak, A. Bartkiewicz
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 chan…
Long-term polarimetric observations of OH127.8+0.0
P. Wolak, M. Szymczak, E. Gerard
OH 1612 and 1667 MHz masers from the well known object OH127.8+0.0 were mon- itored in full-polarization mode over a period of 6.5 years and mapped with MERLIN at one epoch. The OH…
Polarization properties of OH masers in AGB and post-AGB stars
Paweł Wolak, Marian Szymczak, Eric Gérard
Context: Ground-state OH maser emission from late-type stars is usually polarized and remains a powerful probe of the magnetic field structure in the outer regions of circumstellar…
Periodic variability of 6.7GHz methanol masers in G22.357+0.066
M. Szymczak, P. Wolak, A. Bartkiewicz +1
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 m…