@article{d459e1cbc4444522b9de56df766ad867,
title = "Methanol and water maser observations separate disc and outflow sources in IRAS 19410+2336",
abstract = "We investigate the kinematics of high-mass protostellar objects within the high-mass starforming region IRAS 19410+2336. We performed high angular resolution observations of 6.7-GHz methanol and 22 GHz water masers using the Multi-Element Radio Linked Interferometer Network (MERLIN) and e-MERLIN interferometers. The 6.7-GHz methanol maser emission line was detected within the ~16-27 km s -1 velocity range with a peak flux density ~50 Jy. The maser spots are spread over ~1.3 arcsec on the sky, corresponding to ~2800 au at a distance of 2.16 kpc. These are the first astrometric measurements at 6.7 GHz in IRAS 19410+2336. The 22-GHz water maser line was imaged in 2005 and 2019 (the latter with good astrometry). Its velocities range from 13 to ~29 km s -1. The peak flux density was found to be 18.7 and 13.487 Jy in 2005 and 2019, respectively. The distribution of the water maser components is up to 165 mas, ~350 au at 2.16 kpc. We find that the Eastern methanol masers most probably trace outflows from the region of millimetre source mm1. The water masers to the West lie in a disc (flared or interacting with outflow/infall) around another more evolved millimetre source (13-s). The maser distribution suggests that the disc lies at an angle of 60° or more to the plane of the sky and the observed line-of-sight velocities then suggest an enclosed mass between 44M ⊙ and as little as 11M ⊙ if the disc is edge-on. The Western methanol masers may be infalling. ",
keywords = "Masers, Stars: formation, Stars: individual: IRAS 19410+2336, Stars: massive",
author = "Darwish, {M. S.} and Edris, {K. A.} and Richards, {A. M. S.} and S. Etoka and Saad, {M. S.} and Beheary, {M. M.} and Fuller, {G. A}",
note = "Funding Information: We warmly thank Prof. R. Battye, M. Gray, and R. Beswick, and the rest of the e-MERLIN team for guidance in reducing these data. We also remember the important role of the late Dr. Jim Cohen in the initiation of this project.We thank the referee for very helpful comments, which have improved this paper. e-MERLIN is the UK radio interferometer array, operated by the University of Manchester on behalf of Science and Technology Facilities Council (STFC).We acknowledge the use of MERLIN archival data as well as NASA's Astrophysics Data System Service. MD would like to acknowledge the Science and Technology Development Fund N5217, Academy of Scientific Research and Technology, Cairo, Egypt and Kottamia Center of Scientific Excellence for Astronomy and Space Sciences (KCSEASSc), National Research Institute of Astronomy and Geophysics. Our sincere thanks to H. Beuther and F. Widmann for their helpful discussion. Funding Information: We warmly thank Prof. R. Battye, M. Gray, and R. Beswick, and the rest of the e-MERLIN team for guidance in reducing these data. We also remember the important role of the late Dr. Jim Cohen in the initiation of this project. We thank the referee for very helpful comments, which have improved this paper. e-MERLIN is the UK radio interferometer array, operated by the University of Manchester on behalf of Science and Technology Facilities Council (STFC). We acknowledge the use of MERLIN archival data as well as NASA{\textquoteright}s Astrophysics Data System Service. MD would like to acknowledge the Science and Technology Development Fund N5217, Academy of Scientific Research and Technology, Cairo, Egypt and Kottamia Center of Scientific Excellence for Astronomy and Space Sciences (KCSEASSc), National Research Institute of Astronomy and Geophysics. Our sincere thanks to H. Beuther and F. Widmann for their helpful discussion. Publisher Copyright: {\textcopyright} 2020 The Author(s).",
year = "2020",
month = apr,
day = "1",
doi = "10.1093/mnras/staa574",
language = "English",
volume = "493",
pages = "4442--4452",
journal = "Royal Astronomical Society. Monthly Notices",
issn = "1365-2966",
publisher = "Oxford University Press",
number = "3",
}