Facial reconstruction

Search LJMU Research Online

Browse Repository | Browse E-Theses

RINGO3 polarimetry of the Type I superluminous SN 2017egm

Maund, JR, Steele, IA, Jermak, HE, Wheeler, JC and Wiersema, K (2018) RINGO3 polarimetry of the Type I superluminous SN 2017egm. Monthly Notices of the Royal Astronomical Society, 482 (3). pp. 4057-4061. ISSN 0035-8711

RINGO3 polarimetry of the Type I superluminous SN 2017egm.pdf - Published Version

Download (1MB) | Preview


The origin of the luminosity of superluminous supernovae (SLSNe) is an unresolved mystery, and a number of very different physical scenarios (including energy injection from magnetars, collision with a dense circumstellar medium, and pair instability-induced explosions) have been invoked. The application of polarimetry to normal SNe has been shown to probe the three-dimensional structure of exploding stars, providing clues to the nature of the explosion mechanism. We report imaging linear polarimetry observations of the Type I SLSN 2017egm, in the galaxy NGC 3191, conducted with the Liverpool Telescope and the RINGO3 instrument. Observations were acquired at four epochs, spanning 4–19 d after light curve maximum, however, polarization was not detected at a level of >3σ. At +7 and + 15 d, and in the average over all epochs, we find a possible polarization signal, detected at a significance of ≈2σ in the ‘blue’ channel. This signal is seen, primarily, in the Stokes q parameter, with a corresponding polarization angle consistent with the orientation of the spiral arm in proximity to the position of SN 2017egm. We interpret this as indicating that any polarization, if present, originates from dust in the host galaxy rather than being intrinsic to the SN itself. Despite its apparent peculiarities, compared to other Type I SLSNe, the polarization characteristics of SN 2017egm are consistent with the previously reported low polarization of other SLSNe of this variety.

Item Type: Article
Additional Information: This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society ©: 2018 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.
Uncontrolled Keywords: 0201 Astronomical and Space Sciences
Subjects: Q Science > QB Astronomy
Q Science > QC Physics
Divisions: Astrophysics Research Institute
Publisher: Oxford University Press
Related URLs:
Date Deposited: 06 Aug 2019 10:14
Last Modified: 04 Sep 2021 09:03
DOI or ID number: 10.1093/mnras/sty2963
URI: https://researchonline.ljmu.ac.uk/id/eprint/11147
View Item View Item