PSN J12262933+3113383 in NGC4414

[Robin Leadbeater]

Star Analyser user Gianluca Masi has obtained an image and a low resolution SA100 spectrum of this object in NGC4414 which shows no obvious features. Further spectra of this currently mag 14 object are encouraged.

http://www.cbat.eps.harvard.edu/unconf/ ... 13383.html
http://www.rochesterastronomy.org/super ... 33+3113383

Robin

[Paolo Berardi]

Hi Robin, this is a very quick check (11 june) with Lhires III and 150 l/mm grating. Only 35 mins integration in binning 4x4. Target is faint and spectrum noisy. Anyway I try to extract the profile.

The 2d spectrum and slit view:



Spectral profile calibrated (wavelength & relative intensities):



Gelato, the system provides automatic recognition, provides in first instance an analogy with type IIn SN2009au at 4 days age:



Most items in report are SN II type in early stage:



I perform observation and data reduction very quickly and hope I have not made mistakes. Target profile is very poor in features (perhaps it is normal in the early days of a SN event) but it could also be for low SNR or other. It would be good to have a further confirmation.

Ciao
Paolo

[Robin Leadbeater]

Hi Paolo,

The lack of features seems to confirm Gianluca's spectrum. Type II normally show strong H alpha emission. Perhaps it will develop. I see it is still listed at rochesterastronomy as type unknown. Anyone know where best to report these observations?

Robin

[Robin Leadbeater]

Now confirmed as SN 2013df (CBET 3557) type II with a weak P Cyg H alpha line in a spectrum from Keck II. Similar to 1993J which was also in your GELATO list Paolo so your classification was good

Cheers
Robin

[Christian Buil]

A spectrum of SN2014df in NGC4414 taken with a (small) 200-mm telescope (June 14). First the image:



and the spectrum:


(taken in bin1x1 mode with Atik460EX CCD camera)

I confirm, the Halpha line is very weak (!) on this tyoe II supernova!

See also my 2013 supernova page:

http://www.astrosurf.com/buil/supernovae/2013/obs.htm

Christian

[Paolo Berardi]

A lot of information, thank you Robin and Christian (very nice spectrum)! I'm glad to know that Gelato interface is able to working also with so low SNR spectra.

Concerning spectrum profile I read from "OPTICAL SPECTRA OF SUPERNOVAE", Filippenko A. Astron. Astrophys. 1997. 35: 309-355 (http://ned.ipac.caltech.edu/level5/Marc ... rames.html), about type IIP SN:

"At very early times, the spectrum is nearly featureless and quite blue, indicating a high color temperature ( 10,000 K). Very weak hydrogen Balmer lines and He I 5876 are often visible"

Now I'm trying another observation, I hope to integrate more signal than my last session. Not an easy target for me. I'm guiding on host galaxy nucleus (no valid star around). I'll show the result if I can get the job done.

Ciao
Paolo

[Paolo Berardi]

Updating with 13/6 observation. Binning 2x2 and 35 micron slit, 12x600s.
Wavelength calibration with ISIS lateral mode on sky pollution lines.

The profile is still very noisy but some features become visible also here:



Another Gelato fit with new profile:



Paolo

[Christian Buil]

Excellent matching Paolo !

A spectrum taken the 15.9 / 06 (Celestron 11 + Alpy600 + Atik460 bin 1x1) :



(can be downoad from http://www.astrosurf.com/buil/supernovae/2013/obs.htm

Christian