English

A multi-wavelength study of nearby starburst galaxy M 82

Astrophysics of Galaxies 2026-02-25 v1 Cosmology and Nongalactic Astrophysics High Energy Astrophysical Phenomena

Abstract

We present a multi-wavelength study of the nearby starburst galaxy M 82 by combining high-resolution Far-ultraviolet (FUV) imaging from the Ultra-Violet Imaging Telescope (UVIT) onboard AstroSat and archival Chandra X-ray observations. Using FUV flux measurements, we estimate a spatially-resolved star formation rate (SFR) across several star-forming clumps within a radius of \sim3.6 kpc, finding a total SFR of 0.022 M_{\odot} yr1^{-1}. The Hα_{\alpha} recombination line flux yields an SFR of \sim0.010 M_{\odot} yr1^{-1}, while the infrared-based SFR derived from 24 μm\mu\mathrm{m} emission is significantly higher at 16 - 18 M_{\odot} yr1^{-1}, suggesting that a substantial fraction of star formation in M 82 is heavily dust-obscured. Morphological comparison of FUV, Hα_{\alpha}, mid-infrared, and soft X-ray emission reveals a strong spatial correlation, tracing multi-phase outflows along the galaxy's minor axis. X-ray spectral analysis using a three-temperature VAPEC\texttt{VAPEC} model shows enhanced abundances of Ne, Mg, Si, and S, consistent with enrichment from Type-II supernovae. These results demonstrate the importance of combining UV, optical, IR, and X-ray observations to probe both obscured and unobscured star formation, the metal enrichment, and the outflow-driven evolution of starburst galaxies.

Keywords

Cite

@article{arxiv.2602.20786,
  title  = {A multi-wavelength study of nearby starburst galaxy M 82},
  author = {Nilkanth Vagshette and Satish S. Sonkamble and Madhav Patil and Sachindra Naik and Ilani Loubser},
  journal= {arXiv preprint arXiv:2602.20786},
  year   = {2026}
}

Comments

Accepted for publication in Astrophysics (Ap) Journal