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

The Type~Ia supernova (SN~Ia) 2016coj in NGC 4125 (redshift $z=0.004523$) wasdiscovered by the Lick Observatory Supernova Search 4.9 days after the fittedfirst-light time (FFLT; 11.1 days before $B$-band maximum). Our first detection(pre-discovery) is merely $0.6\pm0.5$ day after the FFLT, making SN 2016coj oneof the earliest known detections of a SN Ia. A spectrum was taken only 3.7 hrafter discovery (5.0 days after the FFLT) and classified as a normal SN Ia. Weperformed high-quality photometry, low- and high-resolution spectroscopy, andspectropolarimetry, finding that SN 2016coj is a spectroscopically normal SNIa, but with a high velocity of \ion{Si}{2} $\lambda$6355 ($\sim 12,600$\,\kms\around peak brightness). The \ion{Si}{2} $\lambda$6355 velocity evolution canbe well fit by a broken-power-law function for up to a month after the FFLT. SN2016coj has a normal peak luminosity ($M_B \approx -18.9 \pm 0.2$ mag), and itreaches a $B$-band maximum \about16.0~d after the FFLT. We estimate there to below host-galaxy extinction based on the absence of Na~I~D absorption lines inour low- and high-resolution spectra. The spectropolarimetric data exhibit weakpolarization in the continuum, but the \ion{Si}{2} line polarization is quitestrong ($\sim 0.9\% \pm 0.1\%$) at peak brightness.

Discovery and Follow-up Observations of the Young Type Ia Supernova 2016coj