Nova Alert - PNV J19150199+0719471

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Nova Alert - PNV J19150199+0719471

Beitragvon Thomas Eversberg » 02. Juni 2013, 15:27:05 PM

Hi all! Yesterday the following Nova Alert came from our french colleagues: http://tech.groups.yahoo.com/group/spec ... sage/14168

Knud Strandbeck and me (team 2 of the present Teide campaign) spontaneously stopped our ongoing WR programm and took a 600s echelle spectrum of this 11mag beast. Attached are the spectra independently quick-reduced by Martin Dubs and Lothar Schanne (ISIS and MIDAS, respectively). It seems that various emission lines in Halpha, He and Carbon are visible. The most prominent is Halpha with an 82km/s width. We now discuss with our Montreal PIs how to proceed. Next night we will take a 1800s spectrum and see what we can do.

Cheers, Thomas
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Zuletzt geändert von Thomas Eversberg am 03. Juni 2013, 00:24:37 AM, insgesamt 2-mal geändert.
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Nova Alert - PNV J06270375+3952504

Beitragvon thierry Garrel » 02. Juni 2013, 15:38:21 PM

Hi all,it seems not to be a nova spectrum. H alpha profile is typical of emission from a circumstellar disk, carbon lines may came from a hot component. Not a classical nova but something like a cataclysmic variable, dwarf nova. Also photometric surperhump were detected on VSNET. 
This spectra is the first i've seen from the PN and for this is important to produce quickly. You may send it to ATel or VSNET.
Cheers
Thierry





2013/6/2 Thomas Eversberg <fg-spek-convento@vds-astro.de (fg-spek-convento@vds-astro.de)>
Hi all! Yesterday the following Nova Alert came from our french colleagues: http://tech.groups.yahoo.com/group/spectro-l/message/14168

Knud Strandbeck (team 2 of the present Teide campaign) spontaneously stopped our ongoing WR programm and took a 600s echelle spectrum of this 11mag beast. Attached are the spectra independently quick-reduced by Martin Dubs and Lothar Schanne (ISIS and MIDAS, respectively). It seems that various emission lines in Halpha, He and Carbon are visible. The most prominent is Halpha with an 82km/s width. We now discuss with our Montreal PIs how to proceed. Next night we will take a 1800s spectrum and see what we can do.

Cheers, Thomas





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Beitragvon Thomas Eversberg » 02. Juni 2013, 15:56:33 PM

Yes, it is a dwarf nova.
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Nova Alert - PNV J06270375+3952504

Beitragvon thierry Garrel » 02. Juni 2013, 15:57:50 PM

Would you like to send quickly the link to VSNET or i can do it for you ?Good shot !
T



2013/6/2 Thomas Eversberg <fg-spek-convento@vds-astro.de (fg-spek-convento@vds-astro.de)>
Yes, it is a dwarf nova.





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Beitragvon Thomas Eversberg » 02. Juni 2013, 16:01:12 PM

Hi Thierry, we are very busy here at the summit. I already told Martin Dubs to announce it on behalf of the entire campaign. Note that it is not the spectrum of Knud and me but of the entire ProAm Teide team, hence, also yours. Could you please get in touch with him to organize the announcement at the respective organizations?

Cheers, Thomas
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Beitragvon Thomas Eversberg » 02. Juni 2013, 16:02:33 PM

Just proceed! :D

This is an exciting issue...........
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Nova Alert - PNV J06270375+3952504

Beitragvon thierry Garrel » 02. Juni 2013, 16:16:22 PM

I had quickly sent the link of the forum on VSNET list.Also a low resolution were taken yesterday by Thibault de France available here http://spektroskopieforum.vdsastro.de/viewtopic.php?p=23389#23389
Definitively not a classical nova.





2013/6/2 Thomas Eversberg <fg-spek-convento@vds-astro.de (fg-spek-convento@vds-astro.de)>
Just proceed! Bild

This is an exciting issue...........





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Beitragvon Thomas Eversberg » 02. Juni 2013, 16:45:08 PM

Do you have a link?
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Nova Alert - PNV J06270375+3952504

Beitragvon thierry Garrel » 02. Juni 2013, 17:53:53 PM

Sorry http://www.hd182989.info/nova


2013/6/2 Thomas Eversberg <fg-spek-convento@vds-astro.de (fg-spek-convento@vds-astro.de)>
Do you have a link?





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Nova Alert - PNV J06270375+3952504

Beitragvon Tony Moffat » 02. Juni 2013, 18:09:12 PM

It seems to be a dwarf nova in eruption as a nova, something they do every 10^{4-5} years. Both fall in the class of cataclysmic variable, i.e. low-mass accreting close binary with a WD and a low-mass companion as donor star. I?m asking my colleague Mike Shara what he thinks about continuing to observe this star.

Tony

From: thierry Garrel (fg-spek-convento@vds-astro.de)
Sent: Sunday, June 02, 2013 11:39 AM
To: fg-spek-convento@vds-astro.de (fg-spek-convento@vds-astro.de)
Subject: [fg-spek] Re: Nova Alert - PNV J06270375+3952504




Hi all,it seems not to be a nova spectrum. H alpha profile is typical of emission from a circumstellar disk, carbon lines may came from a hot component. Not a classical nova but something like a cataclysmic variable, dwarf nova. Also photometric surperhump were detected on VSNET.
This spectra is the first i've seen from the PN and for this is important to produce quickly. You may send it to ATel or VSNET.
Cheers
Thierry





2013/6/2 Thomas Eversberg )vds-astro.de (fg-spek-convento(==>)vds-astro.de ([email]fg-spek-convento(==>)vds-astro.de[/email]))>
: Hi all! Yesterday the following Nova Alert came from our french colleagues: http://tech.groups.yahoo.com/group/spectro-l/message/14168

Knud Strandbeck (team 2 of the present Teide campaign) spontaneously stopped our ongoing WR programm and took a 600s echelle spectrum of this 11mag beast. Attached are the spectra independently quick-reduced by Martin Dubs and Lothar Schanne (ISIS and MIDAS, respectively). It seems that various emission lines in Halpha, He and Carbon are visible. The most prominent is Halpha with an 82km/s width. We now discuss with our Montreal PIs how to proceed. Next night we will take a 1800s spectrum and see what we can do.

Cheers, Thomas









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Observatoire de Fontcaude, Montpellier, France
SpectroBlog http://gabalou.canalblog.com/
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Beitragvon Thomas Eversberg » 02. Juni 2013, 18:40:18 PM

Very well, Tony, at least Mike as an expert can give some advice. I hesitate to disturb our campaign but we should think about it as a potentially valuable target. If Mike says no, then we continue as it is.

Cheers, Thomas
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Beitragvon Martin Dubs » 02. Juni 2013, 21:11:32 PM

Hello Thomas,

looking a bit closer at the spectrum, reanalyzing it with a more recent response curve and comparing it with a spectrum of the sky background taken a few days earlier I come to the conclusion that the lines around 6600 and at 6678 are due to the sky background, as well as the strong lines further towards the infrared. I attach a very rough spectrum of the sky background. The waves in this spectrum arise because it is quite difficult to correct the blaze function with almost zero intensity, but it shows where the orders are merged (increase of noise).

I think it would be advisable to record a background spectrum with the next spectrum of the suspected dwarf nova, if there is sufficient time.

Regards, Martin
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comparisonnovaAql_sky.jpg
comparison of Nova Aql with sky background, shifted and scaled for clarity
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Beitragvon Thomas Eversberg » 02. Juni 2013, 21:19:55 PM

Ok, that makes sense.

I can do a sky exposure right beside the target for some minutes but certainly not very long. What do you suggest for exposure time?
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Beitragvon Martin Dubs » 02. Juni 2013, 21:38:12 PM

Hallo Thomas,

the sky spectrum above was recorded for 1x600 sec. If you cannot spend much time this should be the minimum, more is better.

Martin
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Beitragvon Thomas Eversberg » 02. Juni 2013, 21:44:17 PM

Ok, I understand. 1.5 hours target plus, say 0.5 hours sky would significantly reduce our program time (presently 1/3). Hmm, sounds not very good. I will do it this night but then we definitely need to make up our mind. When I get no additional and encouraging input from our PIs I will stop this track.
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Nova Alert - PNV J06270375+3952504

Beitragvon Robin Leadbeater » 02. Juni 2013, 23:43:21 PM

Which PNV are you looking at? The one in the message header and the spectrum posted by Thierry is an old one. The alert is for
PNV J19150199+0719471
R.A. 19:15:02.047 decl. +07:19:46.78 (J 2000.0) Robin


----- Original Message ----- From: Thomas Eversberg (fg-spek-convento@vds-astro.de)
To: fg-spek-convento@vds-astro.de (fg-spek-convento@vds-astro.de)
Sent: Sunday, June 02, 2013 4:27 PM
Subject: [fg-spek] Nova Alert - PNV J06270375+3952504



Hi all! Yesterday the following Nova Alert came from our french colleagues: http://tech.groups.yahoo.com/group/spectro-l/message/14168

Knud Strandbeck (team 2 of the present Teide campaign) spontaneously stopped our ongoing WR programm and took a 600s echelle spectrum of this 11mag beast. Attached are the spectra independently quick-reduced by Martin Dubs and Lothar Schanne (ISIS and MIDAS, respectively). It seems that various emission lines in Halpha, He and Carbon are visible. The most prominent is Halpha with an 82km/s width. We now discuss with our Montreal PIs how to proceed. Next night we will take a 1800s spectrum and see what we can do.

Cheers, Thomas
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Beitragvon Thomas Eversberg » 03. Juni 2013, 00:13:32 AM

What do you mean, Robin, it is this one: http://tech.groups.yahoo.com/group/spec ... sage/14168

Thomas
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Beitragvon Thomas Eversberg » 03. Juni 2013, 00:24:09 AM

Ah, I see! Yes, I annonced the wrong number in the header. Well, just a number... :lol:
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Nova Alert - PNV J06270375+3952504

Beitragvon Robin Leadbeater » 03. Juni 2013, 00:35:02 AM

Yes, but this message thread is headed PNV J06270375+3952504 which was in April and the spectrum linked by Thierry is also headed PNV J19150199+0719471
The possible nova alert is for PNV J19150199+0719471 in Aql
http://ooruri.kusastro.kyoto-u.ac.jp/mailarchive/vsnet-alert/15768
(I am on it currently using my new Alpy low resolution spectrograph)
Robin

----- Original Message ----- From: Thomas Eversberg (fg-spek-convento@vds-astro.de)
To: fg-spek-convento@vds-astro.de (fg-spek-convento@vds-astro.de)
Sent: Monday, June 03, 2013 1:13 AM
Subject: [fg-spek] Re: Nova Alert - PNV J06270375+3952504



What do you mean, Robin, it is this one: http://tech.groups.yahoo.com/group/spectro-l/message/14168

Thomas
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Beitragvon Thomas Eversberg » 03. Juni 2013, 00:52:46 AM

...this message thread is headed PNV J06270375+3952504...

Not anymore! :P

Aha, you are on it, too. Keep us informed, please, and show a spectrum asap. We are waiting for input from Mike Shara (NY) and then we make up our mind.

Good luck to Cumbria
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Nova Alert - PNV J19150199+0719471

Beitragvon Robin Leadbeater » 03. Juni 2013, 00:55:48 AM

(I am on it currently using my new Alpy low resolution spectrograph)



Here is a quick plot of the first 20min exposure from tonight

Cheers
Robin


----- Original Message ----- From: Thomas Eversberg (fg-spek-convento(==>)vds-astro.de ([email]fg-spek-convento(==>)vds-astro.de[/email]))
To: fg-spek-convento(==>)vds-astro.de ([email]fg-spek-convento(==>)vds-astro.de[/email]) (fg-spek-convento(==>)vds-astro.de ([email]fg-spek-convento(==>)vds-astro.de[/email]))
Sent: Monday, June 03, 2013 1:13 AM
Subject: [fg-spek] Re: Nova Alert - PNV J06270375+3952504



What do you mean, Robin, it is this one: http://tech.groups.yahoo.com/group/spectro-l/message/14168

Thomas
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pnv_aql_20130602.png
pnv_aql_20130602.png (11.23 KiB) 13531-mal betrachtet
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Nova Alert - PNV J19150199+0719471

Beitragvon Robin Leadbeater » 03. Juni 2013, 01:06:43 AM

Note this was at ~30deg elevation and is uncorrected for extinction so the drop at the blue end will be exagerated

Robin

----- Original Message ----- From: Robin Leadbeater (fg-spek-convento@vds-astro.de)
To: fg-spek-convento@vds-astro.de (fg-spek-convento@vds-astro.de)
Sent: Monday, June 03, 2013 1:56 AM
Subject: [fg-spek] Re: Nova Alert - PNV J19150199+0719471



: (I am on it currently using my new Alpy low resolution spectrograph)



Here is a quick plot of the first 20min exposure from tonight

Cheers
Robin
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Beitragvon Thomas Eversberg » 03. Juni 2013, 01:06:53 AM

Nice stuff and in good agreement with our observations. We just finished a one hour exposure (lost 15 additional minutes due to read-out trouble). Now we do a 30 minutes sky background exposure. Hopefully, Martin and/or Lothar have reduced it tommorrow. Unfortunately, it is a bit faint and we need such a long exposure time. And, of course, we want to continue our initial program.

Cheers, Thomas
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Nova Alert - PNV J06270375+3952504

Beitragvon thierry Garrel » 03. Juni 2013, 06:06:05 AM

Here is comments from Taichi Kato, Kyoto university. He encourages observations, specially eshel, but i don't think we could included it in the already heavy program.

Thierry


"So it is a WZ Sge-type dwarf nova with a moderate inclination (not so high enough to show large-amplitude early superhumps).But Halpha is stronger than in WZ Sge!    Please try one full-orbit spectroscopy (time resolution several minutes, total duration 2 hours).  You will be able to obtaina spiral pattern like: http://adsabs.harvard.edu/abs/2002PASJ...54L...7B    If you can follow the object on several nights, you will be able to see how the spiral pattern (the result of the 2:1 resonance) evolves.  Please try.    If you are not familiar with the 2:1 resonance, see: http://adsabs.harvard.edu/abs/2002A%26A...383..574O    Please include He II 4686.  This line will be a good tracer for this stage of WZ Sge-type outburst."





2013/6/3 Thomas Eversberg <fg-spek-convento@vds-astro.de (fg-spek-convento@vds-astro.de)>
Ah, I see! Yes, I annonced the wrong number in the header. Well, just a number... Bild





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Beitragvon Martin Dubs » 03. Juni 2013, 13:24:18 PM

Latest results,

here is a comparison of last night spectrum with the night before:
Notice that in the last spectrum the calibration lines have disappeared. The first spectrum of the nova had a readout error, so it was discarded. The remaining 5 images were combined to 5x600 sec exposure, which explains the slightly better S/N compared with the first spectrum. The differences in H-alpha are small, may well be noise. A time series of single exposures of 600 sec each showed little variation, it looks that the S/N is not quite sufficient for such an analysis.
Maybe with a separate campaign some trends of spectral changes could be established, but in a short experiment it will be difficult to find a periodic change.

Thierry,
is anything known about the period of the assumed binary or the spectral class and luminosity of the secondary for this object? Is something very similar to WZ Sge expected? I am not familiar with this type of dwarf novae.

Spectra are uploaded to the server as usual.

Martin
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comparison novaAql 24h.jpg
comparison Nova Aql within 24 hours
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Nova Alert - PNV J19150199+0719471

Beitragvon thierry Garrel » 03. Juni 2013, 14:12:50 PM

Orbital period is 2H so time series of 10 min during an entire period should well show a dance of the ha peaks. Well the weak absorption see in the emission line is a sign of near pole on view and the V/R ratio shouldn't be strong. But HeII 4686 should show stronger V/R variations than ha, cause of it is a high temperature ionization line concerning only the hot spot, who gave photometric superhumps during revolution of the circumstellar disk. In this blue part the snr is better than ha because it is a blue object. A gaussian filter at 2 or 3 times the instrumental resolution will remove the spikes and make profile cleaner for exploitation. That's what we used to do on such time series for pulsating stars. The five single exposures should be of interest for this new object and certainly a good opportunity of paper for professional involved in cataclysmic variable. A complete coverage of the orbital period is better, once if it could be done.
The sky is full of wonder and surprise. During the next four month at Teide, there will be certainly other nova or SN to observe if thre is enough room for this.
T



2013/6/3 Martin Dubs <fg-spek-convento@vds-astro.de (fg-spek-convento@vds-astro.de)>
Latest results,

here is a comparison of last night spectrum with the night before:
Notice that in the last spectrum the calibration lines have disappeared. The first spectrum of the nova had a readout error, so it was discarded. The remaining 5 images were combined to 5x600 sec exposure, which explains the slightly better S/N compared with the first spectrum. The differences in H-alpha are small, may well be noise. A time series of single exposures of 600 sec each showed little variation, it looks that the S/N is not quite sufficient for such an analysis.
Maybe with a separate campaign some trends of spectral changes could be established, but in a short experiment it will be difficult to find a periodic change.

Thierry,
is anything known about the period of the assumed binary or the spectral class and luminosity of the secondary for this object? Is something very similar to WZ Sge expected? I am not familiar with this type of dwarf novae.

Spectra are uploaded to the server as usual.

Martin





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Beitragvon Thomas Eversberg » 03. Juni 2013, 15:07:16 PM

Hi all! I had an email exchange with Nicole, Tona and Noel about this issue. We tried to contact an expert, Mike Shara (NY), but got no reaction yet. We all agree that this target is not matching our instrumentation (as you also pointed out). So we suggest to stick on our program and stop with this Nova.

If you disagree please say it.

Cheers, Thomas
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Beitragvon Martin Dubs » 03. Juni 2013, 15:55:24 PM

Thomas,
this is ok with me.

Thierry;
the S/N at 4646 A is not better than at H-alpha for some reason. In addition there is no He II emission to be seen. Apart from H-alpha I only see He I at 5876 and H-beta at 4861 A, very weak. At 10 min exposure S/N decreases, so longer time series would be needed to find a periodicity with this equipment. Therefore not much time would remain for the main goal of the campaign, as these objects are all seen at the same time of the night.

Martin
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Beitragvon Thomas Eversberg » 03. Juni 2013, 17:29:02 PM

Hi all! We got a clera statment from Mike Share, Professor at the Museum of Natural History in NY.

Don't do the nova. Do the WR!!! Mike


The Nova is out of our program.

Cheers, thomas
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Beitragvon thierry Garrel » 13. Juni 2013, 09:38:22 AM

some news from VSNET. New spectroscopy show that the system would be a WD acretor and a brown dwarf as low mass companion donator. A very interesting system.

"Hello,

We conducted Echelle observations of PNV Aql on June 3 during 2.5
hours with the 2.1m telescope
at the San Pedro M=E1rtir Observatory.
We detected a strong double-peaked H alfa line in emission, while H
Beta shows a
broad and shallow abosrption with a weak core in emission. H Gamma and
Delta are almost absent.
He I 4471 shows a weak absorption.

Radial velocities of H alfa shows a clear orbital period of P(orb)
0.06164 days. The semi amplitude of the
radial velocity curve is only K = 15 km/s, which for a high
inclination system (as presumed by the double peak H alfa line)
suggests a very low mass companion, possibly a brown dwarf. If this
proves correct we should be able
to observe the Balmer lines of the white dwarf when it returns to
quiescence.

Dr. Juan Echevarria

The following observers and colleagues have contributed to these
observations: Gonzalez-Buitrago, Olivares and Rafael Costero"
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