English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

We discuss the absorption due to various constituents of the interstellarmedium of M82 seen in moderately high resolution, high signal-to-noise ratiooptical spectra of SN 2014J. Complex absorption from M82 is seen, at velocities45 $\le$ $v_{\rm LSR}$ $\le$ 260 km s$^{-1}$, for Na I, K I, Ca I, Ca II, CH,CH$^+$, and CN; many of the diffuse interstellar bands (DIBs) are alsodetected. Comparisons of the column densities of the atomic and molecularspecies and the equivalent widths of the DIBs reveal both similarities anddifferences in relative abundances, compared to trends seen in the ISM of ourGalaxy and the Magellanic Clouds. Of the ten relatively strong DIBs consideredhere, six (including $\lambda$5780.5) have strengths within $\pm$20% of themean values seen in the local Galactic ISM, for comparable N(K I); two areweaker by 20--45% and two (including $\lambda$5797.1) are stronger by 25--40%.Weaker than "expected" DIBs [relative to N(K I), N(Na I), and E(B-V)] in someGalactic sight lines and toward several other extragalactic supernovae appearto be associated with strong CN absorption and/or significant molecularfractions. While the N(CH)/N(K I) and N(CN)/N(CH) ratios seen toward SN 2014Jare similar to those found in the local Galactic ISM, the combination of highN(CH$^+$)/N(CH) and high W(5797.1)/W(5780.5) ratios has not been seenelsewhere. The centroids of many of the M82 DIBs are shifted, relative to theenvelope of the K I profile -- likely due to component-to-component variationsin W(DIB)/N(K I) that may reflect the molecular content of the individualcomponents. We compare estimates for the host galaxy reddening E(B-V) andvisual extinction A$_{\rm V}$ derived from the various interstellar specieswith the values estimated from optical and near-IR photometry of SN 2014J.

Diffuse Interstellar Bands vs. Known Atomic and Molecular Species in the Interstellar Medium of M82 toward SN 2014J