CHANG-ES VI: Probing Supernova Energy Deposition in Spiral Galaxies Through Multi-Wavelength Relationships

Jiang-Tao Li; Rainer Beck; Ralf-Jurgen Dettmar; George Heald; Judith Irwin; Megan Johnson; Amanda A. Kepley; Marita Krause; E. J. Murphy; Elena Orlando; Richard J. Rand; A. W. Strong; Carlos J. Vargas; Rene Walterbos; Q. Daniel Wang; Theresa Wiegert

doi:10.1093/mnras/stv2757

paper

CHANG-ES VI: Probing Supernova Energy Deposition in Spiral Galaxies Through Multi-Wavelength Relationships

arXiv:1511.06673 · doi:10.1093/mnras/stv2757

Abstract

How a galaxy regulates its SNe energy into different interstellar/circumgalactic medium components strongly affects galaxy evolution. Based on the JVLA D-configuration C- (6 GHz) and L-band (1.6 GHz) continuum observations, we perform statistical analysis comparing multi-wavelength properties of the CHANG-ES galaxies. The high-quality JVLA data and edge-on orientation enable us for the first time to include the halo into the energy budget for a complete radio-flux-limited sample. We find tight correlations of $L_{radio}$ with the mid-IR-based SFR. The normalization of our $I_{1.6GHz} / W H z^{- 1} - SFR$ relation is $\sim$ 2-3 times of those obtained for face-on galaxies, probably a result of enhanced IR extinction at high inclination. We also find tight correlations between $L_{radio}$ and the SNe energy injection rate $E ˙_{SN (Ia + CC)}$ , indicating the energy loss via synchrotron radio continuum accounts for $\sim 0.1%$ of $E ˙_{SN}$ , comparable to the energy contained in CR electrons. The integrated C-to-L-band spectral index is $α \sim 0.5 - 1.1$ for non-AGN galaxies, indicating a dominance by the diffuse synchrotron component. The low-scatter $L_{radio} - SFR$ / $L_{radio} - E ˙_{SN (Ia + CC)}$ relationships have super-linear logarithmic slopes at $\sim 2 σ$ in L-band ( $1.132 \pm 0.067$ / $1.175 \pm 0.102$ ) while consistent with linear in C-band ( $1.057 \pm 0.075$ / $1.100 \pm 0.123$ ). The super-linearity could be naturally reproduced with non-calorimeter models for galaxy disks. Using Chandra halo X-ray measurements, we find sub-linear $L_{X} - L_{radio}$ relations. These results indicate that the observed radio halo of a starburst galaxy is close to electron calorimeter, and a galaxy with higher SFR tends to distribute an increased fraction of SNe energy into radio emission (than X-ray).

16 pages, 6 figures, 1 table, MNRAS in press

CHANG-ES VI: Probing Supernova Energy Deposition in Spiral Galaxies Through Multi-Wavelength Relationships

Abstract

References in corpus (25)

Cited by in corpus (35)