@article{d9fd70a03ab042c990e1d3c13b1bca9c,
title = "OH maser towards IRAS 06056+2131: polarization parameters and evolution status",
abstract = "We present high-angular resolution observations of OH maser emission towards the high-mass star-forming region IRAS 06056+2131. The observations were carried out using the UK radio interferometer array, Multi-Element Radio Linked Interferometer Network (MERLIN) in the OH main lines at 1665 and 1667 MHz, in addition to the OH satellite line at 1720 MHz. The results of this study reveal the small upper limit to the size of emission in the 1665-MHz line with an estimated total intensity of ~4 Jy. We did not detect any emission from the 1667 and 1720-MHz lines. The full polarization mode of MERLIN enables us to investigate the magnetic field in the OH maser region. In this transition, a Zeeman pair is identified from which a magnetic strength of ~-1.5 mG is inferred. Our results show that IRAS 06056+2131 is highly polarized, with ~ 96 per cent circular polarization and ~6 per cent linear polarization. The linear polarization angle is ~29°, implying a magnetic field which could be aligned with the outflow direction detected towards this region, but the actual magnetic field direction has an uncertainty of up to 110° due to the possible effects of Faraday rotation. The star-forming evolutionary status of the embedded protostellar object is discussed.",
keywords = "Masers, Polarization, Stars: formation, Stars: individual: IRAS 06056+2131, Stars: massive",
author = "Darwish, {Mohamed Said} and Richards, {Anita M. S.} and Sandra Etoka and Khaled Edris and Somaya Saad and Mohamed Beheary and Gary Fullar",
note = "Funding Information: We gratefully 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 initiating this project. We thank the anonymous referee for very insightful and helpful comments which have improved this paper. e-MERLIN is the UK radio interferometer array, operated by the University of Manchester on behalf of STFC. We acknowledge the use of MERLIN archival data as well as NASA{\textquoteright}s Astrophysics Data System Service. M. Darwish would like to acknowledge the Science and Technology Development Fund (STDF) N5217, Academy of Scientific Research and Technology (ASRT), Cairo, Egypt and Kottamia Center of Scientific Excellence for Astronomy and Space Sciences (KCSEASSc), National Research Institute of Astronomy and Geophysics (NRIAG). Our sincere thanks to S. Ellingsen and J. Allotey for their helpful discussion and to C. Sobey for pulsar data. Funding Information: We gratefully 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 initiating this project. We thank the anonymous referee for very insightful and helpful comments which have improved this paper. e-MERLIN is the UK radio interferometer array, operated by the University of Manchester on behalf of STFC. We acknowledge the use of MERLIN archival data as well as NASA's Astrophysics Data System Service. M. Darwish would like to acknowledge the Science and Technology Development Fund (STDF) N5217, Academy of Scientific Research and Technology (ASRT), Cairo, Egypt and Kottamia Center of Scientific Excellence for Astronomy and Space Sciences (KCSEASSc), National Research Institute of Astronomy and Geophysics (NRIAG). Our sincere thanks to S. Ellingsen and J. Allotey for their helpful discussion and to C. Sobey for pulsar data. Publisher Copyright: {\textcopyright} 2020 The Author(s).",
year = "2020",
month = nov,
day = "1",
doi = "10.1093/mnras/staa2810",
language = "English",
volume = "499",
pages = "1441--1449",
journal = "Royal Astronomical Society. Monthly Notices",
issn = "1365-2966",
publisher = "Oxford University Press",
number = "1",
}