TY - JOUR
T1 - Investigating Galactic Supernova Remnant Candidates Using LOFAR
AU - Driessen, Laura N.
AU - Domček, Vladimír
AU - Vink, Jacco
AU - Hessels, Jason W.T.
AU - Arias, Maria
AU - Gelfand, Joseph D.
N1 - Funding Information:
Science Foundation Ireland (SFI), Department of Business, Enterprise and Innovation (DBEI), Ireland; NWO, The Netherlands; The Science and Technology Facilities Council, UK. This paper is also based (in part) on observations obtained with XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA.
Funding Information:
We would like to thank Vincent Morello, George Heald, Raymond Oonk, Andre Offringa, Jess Broderick, Pedro Salas, Alex Mechev, and Irene Polderman for useful discussions and assistance with LOFAR imaging and calibration. L.N.D. and J. W.T.H. acknowledge support from the European Research Council under the European Union’s Seventh Network Framework Programme (FP/2007-2013)/ERC Grant Agreement nr. 337062. J.W.T.H. is an NWO Vidi fellow. This paper is based (in part) on data obtained with the International LOFAR Telescope (ILT) under project code LC4_011. LOFAR (van Haarlem et al. 2013) is the Low Frequency Array designed and constructed by ASTRON. It has observing, data processing, and data storage facilities in several countries, that are owned by various parties (each with their own funding sources), and that are collectively operated by the ILT foundation under a joint scientific policy. The ILT resources have benefited from the following recent major funding sources: CNRS-INSU, Observatoire de Paris and Université d’Orléans, France; BMBF, MIWF-NRW, MPG, Germany;
Publisher Copyright:
© 2018. The American Astronomical Society. All rights reserved.
PY - 2018/6/20
Y1 - 2018/6/20
N2 - We investigate six supernova remnant (SNR) candidates - G51.21+0.11, G52.37-0.70, G53.07+0.49, G53.41+0.03, G53.84-0.75, and the possible shell around G54.1+0.3 - in the Galactic plane using newly acquired Low-Frequency Array High-band Antenna observations, as well as archival Westerbork Synthesis Radio Telescope and Very Large Array Galactic Plane Survey mosaics. We find that G52.37-0.70, G53.84-0.75, and the possible shell around pulsar wind nebula G54.1+0.3 are unlikely to be SNRs, while G53.07+0.49 remains a candidate SNR. G51.21+0.11 has a spectral index of α = - 0.7 ± 0.21, but lacks X-ray observations and as such requires further investigation to confirm its nature. We confirm one candidate, G53.41+0.03, as a new SNR because it has a shell-like morphology, a radio spectral index of α = - 0.6 ± 0.2 and it has the X-ray spectral characteristics of a 1000-8000 year old SNR. The X-ray analysis was performed using archival XMM-Newton observations, which show that G53.41+0.03 has strong emission lines and is best characterized by a nonequilibrium ionization model, consistent with an SNR interpretation. Deep Arecibo radio telescope searches for a pulsar associated with G53.41+0.03 resulted in no detection, but placed stringent upper limits on the flux density of such a source if it was beamed toward Earth.
AB - We investigate six supernova remnant (SNR) candidates - G51.21+0.11, G52.37-0.70, G53.07+0.49, G53.41+0.03, G53.84-0.75, and the possible shell around G54.1+0.3 - in the Galactic plane using newly acquired Low-Frequency Array High-band Antenna observations, as well as archival Westerbork Synthesis Radio Telescope and Very Large Array Galactic Plane Survey mosaics. We find that G52.37-0.70, G53.84-0.75, and the possible shell around pulsar wind nebula G54.1+0.3 are unlikely to be SNRs, while G53.07+0.49 remains a candidate SNR. G51.21+0.11 has a spectral index of α = - 0.7 ± 0.21, but lacks X-ray observations and as such requires further investigation to confirm its nature. We confirm one candidate, G53.41+0.03, as a new SNR because it has a shell-like morphology, a radio spectral index of α = - 0.6 ± 0.2 and it has the X-ray spectral characteristics of a 1000-8000 year old SNR. The X-ray analysis was performed using archival XMM-Newton observations, which show that G53.41+0.03 has strong emission lines and is best characterized by a nonequilibrium ionization model, consistent with an SNR interpretation. Deep Arecibo radio telescope searches for a pulsar associated with G53.41+0.03 resulted in no detection, but placed stringent upper limits on the flux density of such a source if it was beamed toward Earth.
KW - H II regions
KW - ISM: supernova remnants
KW - X-rays: ISM
KW - radio continuum: ISM
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U2 - 10.3847/1538-4357/aac32e
DO - 10.3847/1538-4357/aac32e
M3 - Article
AN - SCOPUS:85049204385
SN - 0004-637X
VL - 860
JO - Astrophysical Journal
JF - Astrophysical Journal
IS - 2
M1 - 133
ER -