Helium emission from Balmer-dominated shocks in Type Ia supernova remnants provides constraints to their progenitor systems

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Das, Priyam, Seitenzahl, Ivo Rolf, Ghavamian, Parviz, Ruiter, Ashley Jade, Laming, J. Martin, Murphy, Simon J., O'Donnel, Cillian
Format: Preprint
Published: 2026
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866917466876149760
author Das, Priyam
Seitenzahl, Ivo Rolf
Ghavamian, Parviz
Ruiter, Ashley Jade
Laming, J. Martin
Murphy, Simon J.
O'Donnel, Cillian
author_facet Das, Priyam
Seitenzahl, Ivo Rolf
Ghavamian, Parviz
Ruiter, Ashley Jade
Laming, J. Martin
Murphy, Simon J.
O'Donnel, Cillian
contents Balmer-dominated shocks in Type Ia supernova remnants offer powerful probes into collisionless shock physics and hints towards supernova progenitor environments. Prior studies focused on the hydrogen Balmer lines, which manifest as a superposition of broad and narrow emission lines. Using integral-field spectroscopy with MUSE, we discovered broad and narrow helium emission lines from Balmer-dominated filaments of three Type Ia supernovae remnants in the Large Magellanic Cloud: SNR 0509-67.5, SNR 0519-69.0 and N103B. We detect broad and narrow He~\textsc{i} 5876~Å~,7065~Å emission in SNR 0519 and N103B and He \textsc{ii} 8236~Å in SNR 0519. In SNR 0509 we detect narrow He~\textsc{i} 5015~Å, 6678~Å, 7065~Å and 7281~Å, with only 7065~Å~ exhibiting a broad component. The detection of narrow He\,\textsc{ii} challenges existing shock models, where such emission is not expected, and may indicate either incomplete ion-ion equilibration behind the shock or an origin in shock precursors. For SNR 0509 and N103B, the neutral He/H line ratios indicate enhanced helium abundances, whereas SNR 0519 is consistent with the primordial He/H value. We therefore propose helium emission in Balmer-dominated shocks as a new diagnostic of shock physics and Type Ia supernova circumstellar environments. Although our modeling is primarily a proof of concept, it demonstrates the possibility to infer the total He-to-H abundance ratio, with dominant uncertainties arising from the assumed initial ionization fractions. Despite the uncertainties, we demonstrate that narrow helium lines can serve as effective probes of circumstellar conditions and progenitor evolution when analysed alongside reliable constraints on the preshock neutral H/He abundance ratio.
format Preprint
id arxiv_https___arxiv_org_abs_2605_05661
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Helium emission from Balmer-dominated shocks in Type Ia supernova remnants provides constraints to their progenitor systems
Das, Priyam
Seitenzahl, Ivo Rolf
Ghavamian, Parviz
Ruiter, Ashley Jade
Laming, J. Martin
Murphy, Simon J.
O'Donnel, Cillian
Solar and Stellar Astrophysics
Astrophysics of Galaxies
High Energy Astrophysical Phenomena
Atomic Physics
Balmer-dominated shocks in Type Ia supernova remnants offer powerful probes into collisionless shock physics and hints towards supernova progenitor environments. Prior studies focused on the hydrogen Balmer lines, which manifest as a superposition of broad and narrow emission lines. Using integral-field spectroscopy with MUSE, we discovered broad and narrow helium emission lines from Balmer-dominated filaments of three Type Ia supernovae remnants in the Large Magellanic Cloud: SNR 0509-67.5, SNR 0519-69.0 and N103B. We detect broad and narrow He~\textsc{i} 5876~Å~,7065~Å emission in SNR 0519 and N103B and He \textsc{ii} 8236~Å in SNR 0519. In SNR 0509 we detect narrow He~\textsc{i} 5015~Å, 6678~Å, 7065~Å and 7281~Å, with only 7065~Å~ exhibiting a broad component. The detection of narrow He\,\textsc{ii} challenges existing shock models, where such emission is not expected, and may indicate either incomplete ion-ion equilibration behind the shock or an origin in shock precursors. For SNR 0509 and N103B, the neutral He/H line ratios indicate enhanced helium abundances, whereas SNR 0519 is consistent with the primordial He/H value. We therefore propose helium emission in Balmer-dominated shocks as a new diagnostic of shock physics and Type Ia supernova circumstellar environments. Although our modeling is primarily a proof of concept, it demonstrates the possibility to infer the total He-to-H abundance ratio, with dominant uncertainties arising from the assumed initial ionization fractions. Despite the uncertainties, we demonstrate that narrow helium lines can serve as effective probes of circumstellar conditions and progenitor evolution when analysed alongside reliable constraints on the preshock neutral H/He abundance ratio.
title Helium emission from Balmer-dominated shocks in Type Ia supernova remnants provides constraints to their progenitor systems
topic Solar and Stellar Astrophysics
Astrophysics of Galaxies
High Energy Astrophysical Phenomena
Atomic Physics
url https://arxiv.org/abs/2605.05661