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Related papers: A Multi-Epoch, Simultaneous Water and Methanol Mas…

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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…

Astrophysics · Physics 2010-01-28 Y. Xu , J. J. Li , K. Hachisuka , J. D. Pandian , K. M. Menten , C. Henkel

This article focuses on NGC7538 IRS1, one of the most luminous and studied HC HII regions in the northern hemisphere. Our aim is to identify the young stellar objects (YSOs) embedded within the ionized gas and study their kinematic…

Solar and Stellar Astrophysics · Physics 2025-03-14 Luca Moscadelli , Ciriaco Goddi , Tomoya Hirota , Alberto Sanna

The changes in the spectral line profile of the 22GHz H2O maser are calculated as a function of emerging maser flux. We address not only the narrowing and re-broadening of the maser lines, but also the deviations of Gaussian symmetry as a…

Astrophysics · Physics 2009-11-10 W. H. T. Vlemmings , H. J. van Langevelde

We present the results of multi-epoch very long baseline interferometry (VLBI) water (H2O) maser observations carried out with the VLBI Exploration of Radio Astrometry (VERA) toward the Cepheus A HW3d object. We measured for the first time…

Four Class I maser sources were detected at 44, 84, and 95 GHz toward chemically rich outflows in the regions of low-mass star formation NGC 1333I4A, NGC 1333I2A, HH25, and L1157. One more maser was found at 36 GHz toward a similar outflow,…

Astrophysics of Galaxies · Physics 2015-06-04 S. V. Kalenskii , V. I. Slysh , L. E. B. Johansson , P. Bergman , S. Kurtz , P. Hofner , C. M. Walmsley

We report the first observations in a rare family of class II methanol maser transitions in both CH$_3$OH and $^{13}$CH$_3$OH toward three southern high-mass star formation regions, along with the first maser detected in the $^{13}$CH$_3$OH…

We report the detection of the millimeter CH$_3$OH masers including a new detection of class I (11$_{0,11}$-10$_{1,10}$A) and class II (6$_{1,5}$-5$_{2,4}$E) maser transitions toward the high-mass protostar S255IR NIRS3 in post-burst phase.…

Solar and Stellar Astrophysics · Physics 2023-09-06 Giseon Baek , Jeong-Eun Lee , Neal J. Evans , Tomoya Hirota , Yuri Aikawa , Ji-hyun Kang , Jungha Kim , Jes K. Jørgensen

We present a study of signatures of on-going star formation in a sample of protostellar objects with enhanced 4.5 {\mu}m emission ('green' sources) near the Galactic center. To understand how star formation in the Galactic center region…

Astrophysics of Galaxies · Physics 2015-05-27 Edward T. Chambers , Farhad Yusef-Zadeh , Doug Roberts

We present 1" resolution CARMA observations of the 3mm continuum and 95 GHz methanol masers toward 14 candidate high mass protostellar objects (HMPOs). Dust continuum emission is detected toward seven HMPOs, and methanol masers toward 5…

Astrophysics of Galaxies · Physics 2011-02-11 S. Schnee , J. Carpenter

We present high angular resolution (FWHM_beam < 0.2") observations of the 23.1-GHz methanol (CH_3OH) transition toward the massive-star forming region NGC 7538 IRS 1. The two velocity components previously reported by Wilson et al. are…

Astrophysics of Galaxies · Physics 2015-05-18 Roberto Galván-Madrid , Gabriela Montes , Edgar A. Ramírez , Stan Kurtz , Esteban Araya , Peter Hofner

In the early days of methanol maser discoveries the 9(2)-10(1) A+ transition at 23.1 GHz was found to exhibit maser characteristics in the northern star-forming region W3(OH), and probable maser emission in two other sources. Attention…

Astrophysics · Physics 2009-11-10 D. M. Cragg , A. M. Sobolev , J. L. Caswell , S. P. Ellingsen , P. D. Godfrey

Astrophysical masers are widely used in star formation studies. In particular, they are valuable in investigations of high-mass star-forming regions that are difficult to observe at optical frequencies. We used multi-transition data to…

Solar and Stellar Astrophysics · Physics 2025-03-17 A. Kobak , A. Bartkiewicz , K. L. J. Rygl , A. M. S. Richards , M. Szymczak , P. Wolak

We present a survey for water maser emission toward a sample of 44 low-luminosity young objects, comprising (proto-)brown dwarfs, first hydrostatic cores (FHCs), and other young stellar objects (YSOs) with bolometric luminosities lower than…

Solar and Stellar Astrophysics · Physics 2017-04-26 Jose F. Gomez , Aina Palau , Lucero Uscanga , Guillermo Manjarrez , David Barrado

This work presents a detailed study of the gas kinematics towards the "Hot Molecular Core" (HMC) G31.41+0.31 via multi-epoch VLBI observations of the H2O 22 GHz and CH3OH 6.7 GHz masers, and single-epoch VLBI of the OH 1.6 GHz masers. Water…

Solar and Stellar Astrophysics · Physics 2015-06-12 Luca Moscadelli , Jing Jing Li , Riccardo Cesaroni , Alberto Sanna , Ye Xu , Qizhou Zhang

We present a search for water maser emission at 22 GHz associated with young low-mass protostars in six HII regions -- M16, M20, NGC 2264, NGC 6357, S125, and S140. The survey was conducted with the NRAO Very Large Array from 2000 to 2002.…

Astrophysics · Physics 2009-11-10 Kevin R. Healy , J. Jeff Hester , Mark J. Claussen

We test models of starburst driven outflows using observations of the 22.2 GHz H$_2$O and 36.2 GHz class I CH$_3$OH maser lines. We have observed the starburst galaxy NGC 253 using the Karl G. Jansky Very Large Array. We present evidence…

Astrophysics of Galaxies · Physics 2019-01-16 Mark Gorski , Jürgen Ott , Richard Rand , David S. Meier , Emmanuel Momjian , Eva Schinnerer , Simon P. Ellingsen

We carried out observations of the 22 GHz H2O masers in a high-mass protostar S255 NIRS 3 by using VERA. We measured the proper motions of the 22 GHz H2O masers associated with a bipolar outflow. The expansion velocity of the blueshifted…

Context. Water vapor emission at 22 GHz from masers associated with star-forming regions is highly variable. Aims. We present a database of up to 20 years of monitoring of a sample of 43 masers within star-forming regions. The sample covers…

Using the Herschel Space Observatory's Heterodyne Instrument for the Far-Infrared (HIFI), we have performed mapping observations of the 620.701 GHz 5(32)-4(41) transition of ortho-H2O within a roughly 1.5 x 1.5 arcmin region encompassing…

Astrophysics of Galaxies · Physics 2015-06-15 David A. Neufeld , Yuanwei Wu , Alex Kraus , Karl M. Menten , Volker Tolls , Gary J. Melnick , Zsofia Nagy

We have used the Australia Telescope Compact Array (ATCA) to make the first high resolution observations of a large sample of class~I methanol masers in the 95-GHz ($8_0$--$7_1$A$^+$) transition. The target sources consist of a…

Astrophysics of Galaxies · Physics 2018-03-28 Tiege P. McCarthy , Simon P. Ellingsen , Maxim A. Voronkov , Giuseppe Cimo