Constraining Magnetic Field Amplification in SN Shocks Using Radio Observations of SNe 2011fe and 2014J

DOI: 
10.3847/1538-4357/aa704c
Publication date: 
01/06/2017
Main author: 
Kundu, E.
IAA authors: 
Pérez-Torres, M. A.;Alberdi, A.
Authors: 
Kundu, E.;Lundqvist, P.;Pérez-Torres, M. A.;Herrero-Illana, R.;Alberdi, A.
Journal: 
The Astrophysical Journal
Refereed: 
Yes
Publication type: 
Article
Volume: 
842
Pages: 
17
Abstract: 

We modeled the radio non-detection of two Type Ia supernovae (SNe), SN 2011fe and SN 2014J, considering synchrotron emission from the interaction between SN ejecta and the circumstellar medium. For ejecta whose outer parts have a power-law density structure, we compare synchrotron emission with radio observations. Assuming that 20% of the bulk shock energy is being shared equally between electrons and magnetic fields, we found a very low-density medium around both the SNe. A less tenuous medium with particle density ∼1 cm<SUP>−3</SUP>, which could be expected around both SNe, can be estimated when the magnetic field amplification is less than that presumed for energy equipartition. This conclusion also holds if the progenitor of SN 2014J was a rigidly rotating white dwarf (WD) with a main-sequence (MS) or red giant companion. For a He star companion, or a MS for SN 2014J, with 10% and 1% of bulk kinetic energy in magnetic fields, we obtain mass-loss rates of 〈 {10}<SUP>-9</SUP> and 〈 ∼ 4× {10}<SUP>-9</SUP> {M}<SUB>ȯ </SUB> {{yr}}<SUP>-1</SUP> for a wind velocity of 100 {km} {{{s}}}<SUP>-1</SUP>. The former requires a mass accretion efficiency of 〉99% onto the WD, but is less restricted for the latter case. However, if the tenuous medium is due to a recurrent nova, it is difficult from our model to predict synchrotron luminosities. Although the formation channels of SNe 2011fe and 2014J are not clear, the null detection in radio wavelengths could point toward a low amplification efficiency for magnetic fields in SN shocks.

Database: 
ADS
SCOPUS
URL: 
https://www.scopus.com/inward/record.uri?eid=2-s2.0-85021076053&doi=10.3847%2f1538-4357%2faa704c&partnerID=40&md5=04bd090820799f857640aa3f734fcc1f
ADS Bibcode: 
2017ApJ...842...17K
Keywords: 
circumstellar matter;ISM: magnetic fields;supernovae: general;supernovae: individual: SN 2011fe;SN 2014J