PNV J06000985+1426152 in Orion

[Paolo Berardi]

A probable outburst of a known star normally shining at mag 19-20. From follow-up I read that now should be around mag 12.8 (unfiltered) and could be a dwarf nova like SU UMa or WZ Sge. I have not yet found any spectra.

IAUC TOCP:
http://www.cbat.eps.harvard.edu/unconf/ ... 26152.html

My attempt in very bad weather conditions. Less than hour with several clouds passage and high turbulence...



It show a blue continuum nearly featureless (at spectrum resolution/SNR) interrupted by h-beta and h-gamma broad absorption hydrogen lines. Other features are very weak. The subject is not very easy, it requires a longer exposure time.

Slit view through C9.25 f/10 and Lhires III:



Paolo

[Paolo Berardi]

The observation of 7.759 march reported on CBAT follow-up:



Paolo

[Paolo Berardi]

New observation of 12 march. Target is less bright but integration is greater:



An unusual thing about 7 march observation. I took 18 x 360 s frames but were used first 13 for spectrum profile extraction due to poor SNR of last frames (for weather problem). While I was checking results depending on used frames, I noticed that profile was slightly different, not only for noise level. So I tried to divide frames in two group, 1-9 and 10-18, obtaining two profiles that show some differences (apart SNR) indicated by arrow:



I wonder if these rapid changes happened in about 1.3h are true (instrinsic of the CV star) or are part of random fluctuations for low SNR.

Paolo

[Francois Teyssier]

That's not impossible Paolo
Here's a list of publications about spectroscopy of dwraf novae outbursts
http://www.astronomie-amateur.fr/Docume ... tburts.pdf
There's not so much survey of dwarf novae in outburst
Time series should be a good subject
François

[Paolo Berardi]

Thank you François, very interesting papers. I hope to observe a brighter dwarf nova or CV outburst in future!

Paolo