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 Tools annual

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 monthly

Global: Zendy Plus monthly

Presents the access of premium content as premium feature

Premium Content

Global: Zendy Plus annual

Global: Zendy Free Plan

We present a comprehensive data set of supernova (SN) 2016adj located withinthe central dust lane of Centaurus A. SN 2016adj is significantly reddened andafter correcting the peak apparent $B$-band magnitude ($m_B = 17.48\pm0.05$)for Milky Way reddening and our inferred host-galaxy reddening parameters(i.e., $R_{V}^{host} = 5.7\pm0.7$ and $A_{V}^{host} = 6.3\pm0.2$), we estimateit reached a peak absolute magnitude of $M_B \sim -18$. Detailed inspection ofthe optical/NIR spectroscopic time-series reveals a carbon-rich SN Ic and not aSN Ib/IIb as previously suggested in the literature. The NIR spectra showsprevalent carbon-monoxide formation occurring already by +41 days past $B$-bandmaximum, which is $\approx 11$ days earlier than previously reported in theliterature for this object. Interestingly around two months past maximum, theNIR spectrum of SN~2016adj begins to exhibit H features, with a +97~d mediumresolution spectrum revealing both Paschen and Bracket lines with absorptionminima of $\sim 2000$ km/s, full-width-half-maximum emission velocities of$\sim 1000$ km/s, and emission line ratios consistent with a dense emissionregion. We speculate these attributes are due to circumstellar interaction(CSI) between the rapidly expanding SN ejecta and a H-rich shell of materialformed during the pre-SN phase. A bolometric light curve is constructed and asemi-analytical model fit suggests the supernova synthesized 0.5 solar massesof $^{56}$Ni and ejected 4.2 solar masses of material, though these valuesshould be approached with caution given the large uncertainties associated withthe adopted reddening parameters, possible CSI contamination, and known lightecho emission. Finally, inspection of Hubble Space Telescope archival datayielded no progenitor detection.

The carbon-rich type Ic supernova 2016adj in the iconic dust lane of Centaurus A: signatures of interaction with circumstellar hydrogen?