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 Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

We report our attempts to locate the progenitor of the peculiar type Ic SN2007gr in HST pre-explosion images of the host galaxy, NGC 1058. Aligningadaptive optics Altair/NIRI imaging of SN 2007gr from the Gemini (North)Telescope with the pre-explosion HST WFPC2 images, we identify the SN positionon the HST frames with an accuracy of 20 mas. Although nothing is detected atthe SN position we show that it lies on the edge of a bright source, 134+/-23mas (6.9 pc) from its nominal centre. Based on its luminosity we suggest thatthis object is possibly an unresolved, compact and coeval cluster and that theSN progenitor was a cluster member, although we note that model profile fittingfavours a single bright star. We find two solutions for the age of this assumedcluster; 7-/+0.5 Myrs and 20-30 Myrs, with turn-off masses of 28+/-4 Msun and12-9 Msun respectively. Pre-explosion ground-based K-band images marginallyfavour the younger cluster age/higher turn-off mass. Assuming the SN progenitorwas a cluster member, the turn-off mass provides the best estimate for itsinitial mass. More detailed observations, after the SN has faded, shoulddetermine if the progenitor was indeed part of a cluster, and if so allow anage estimate to within ~2 Myrs thereby favouring either a high mass single staror lower mass interacting binary progenitor.

The birth place of the type Ic Supernova 2007gr