Hi all,
Not an Earth shattering one but the BOSS team (Me, Greg Bock, Stu Parker, Colin Drescher, Pat Pearl and Brendan Downs) got another to add to our long list (71 in total now and 4 for July!)
The reason I mention this one even though it is faint is because of the circumstances behind the ATel below.
The SN is in a distant galaxy PGC161935 in Telescopium in the same field as NGC6855. The galaxy is about 782 million light years away (a new BOSS record) think about that distance and the journey the light took.
Anyways by sheer luck when we emailed Siding Springs Observatory at about midnite the astronomers were working on another galaxy within arc minutes of this one so we had a spectra within 2 hours of discovery!
Incredible really.
ATel5239
Classification of PSN J20065788-5625312 as a Type Ia SN near max with WiFeS
ATel #5239; M. Childress, R. Scalzo, F. Yuan, B. Schmidt (Australian National University), B. Tucker (ANU, UC Berkeley)
on 31 Jul 2013; 16:21 UT
Distributed as an Instant Email Notice Supernovae
Credential Certification: Michael Childress (mjc@mso.anu.edu.au)
Subjects: Optical, Supernovae
We report spectroscopic classification of PSN J20065788-5625312 as a SN Ia near max based on a 40 minute spectrum obtained with the Wide Field Spectrograph (WiFeS - Dopita et al., 2007, ApSS, 310, 255) on the ANU 2.3m telescope at Siding Spring Observatory, NSW Australia, using the B3000/R3000 gratings (3500-9800 A, 1 A resolution). PSN J20065788-5625312 was discovered by Peter Marples and Greg Bock on 2013 July 31.51 at 17.4 mag, and our spectrum with WiFeS on 2013 July 31.64 indicates it is a Type Ia around maximum light. Classification with SNID (Blondin & Tonry, 2007, ApJ, 666, 1024) shows best match to SN 1994D at -2 days at a redshift of 0.050 +- 0.006, consistent with the redshift of the apparent host galaxy 2MASX J20065644-5625175 (z=0.051946, Jones et al., 2009, MNRAS, 399, 683). Clear SN Ia signatures include Si II 6355 at a rest frame velocity of 12,000 km/s (using host redshift), Si II 5972, the S II "W", O I 7700, Ca H/K, and the Ca II NIR triplet.
Name | RA (J2000) | Dec (J2000) | Disc. Date | Disc. Source | Disc Mag | z | Type | Phase | Notes
PSN J20065788-5625312 | 20 06 57.88 | -56 25 31.2 | 20130731 | Marples, Bock | 17.4 | 0.050 | Ia | -2 |
Peter
I noted the telegram this morning. I thought it unusual because it was from Siding Springs. You guys don't tend to have the Aussies confirm the discoveries.
I didn't note the close time though. Well done.
Here's my pre-discovery image taken 5 days earlier showing the new SN. I missed this one!!! I checked the image for new objects around the larger galaxy, NGC6855, which was centered in the field. I didn't see the tiny little newbie at 18.0 magnitude near PGC161935 at the time, must have been too tired by 1am to notice it..Doh!!
And btw, I get a value of 780 Mlyrs (using H0=72). This is a new distance record for BOSS, previous one being 733 Mlyrs (PGC75651)
Thanks Terry and Allan,
Will post image tonight or can be seen on Bright Supernova Page. http://www.rochesterastronomy.org/supernova.html
Had distance recalculate at 780 million light years away, give or take a few it's BOSS furthest yet!
Thanks Terry and Allan,
Will post image tonight or can be seen on Bright Supernova Page. http://www.rochesterastronomy.org/supernova.html
Had distance recalculate at 780 million light years away, give or take a few it's BOSS furthest yet!
Congratulations Peter and Greg.
I don't think I will try to observe this one
Cheer
Hi Gary, yes we get fantastic co-ordination with a number of professional groups these days, but the Siding Springs team broke a confirmation record last night for us by spectrally confirming it in about an hour and a half.
Yes Dave, a 12" RC...will normally do SN searches, then colour imaging at Leyburn on occasions too.
Hi Gary, yes we get fantastic co-ordination with a number of professional groups these days, but the Siding Springs team broke a confirmation record last night for us by spectrally confirming it in about an hour and a half.
Hi Greg, Peter,
If I were the Siding Spring's ANU team, I would set you up with your own dedicated hotline mobile complete with
"Across the Universe" ringtone.
It could be left in the control room or under Brian Schmidt's pillow.
Yes Dave, a 12" RC...will normally do SN searches, then colour imaging at Leyburn on occasions too.
Ok,
Wouldn't the 14 inch have much better light gathering capability - larger area and smaller central obstruction, or is the lower faster f ratio of the RC scope more significant for your SN patrols?
I think it may have been Tuesday... I remember it like yesterday, the supercontinent Rodinia started breaking up (thanks Google).
