T CrB before its new nova event

Matthieu Le Lain
Posts: 24
Joined: Mon Apr 15, 2019 4:33 pm

Re: T CrB before its new nova event

Post by Matthieu Le Lain »

Hi all,

Here is a new spectrum of T CrB with an alpy on C8 (24/03/2022)
T CrB - 24/03/2022
T CrB - 24/03/2022
Matthieu
Joan Guarro Flo
Posts: 627
Joined: Thu Nov 03, 2011 8:50 pm

Re: T CrB before its new nova event

Post by Joan Guarro Flo »

Hello,

That's T CrB from the SMM remote Observatory this last night.

Regards, J. Guarro.
Attachments
T CrB1.png
T CrB1.png (24.2 KiB) Viewed 5392 times
T CrB2.png
T CrB2.png (30.15 KiB) Viewed 5392 times
T CrB3.png
T CrB3.png (14.08 KiB) Viewed 5392 times
T CrB4.png
T CrB4.png (27.37 KiB) Viewed 5392 times
Francois Teyssier
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Re: T CrB before its new nova event

Post by Francois Teyssier »

Good!
The campaign is restarted after the (too long) seasonal gap
The last spectra show a fast decline of He II line toward 0 in low resolution spectra and very faint in echelle spectra.
This sudden fading after a long decrease could be a clue of the entrance of the system in the last phase before the nova outburst.
A page summarize the current status and the monitoring. It will be updated weekly.
http://www.astronomie-amateur.fr/Erupti ... TCrB0.html

A cadency of 2/3 spectra a week is suggested.
The behavior of the recurrent nova *before* the outburst may provide informations at least as important tahn the nova event in itself.

All the best and thanks in advance for your involvment.

fmt
Last edited by Francois Teyssier on Tue May 02, 2023 6:20 pm, edited 2 times in total.
Francois Teyssier
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Re: T CrB before its new nova event

Post by Francois Teyssier »

Detection of strong flickering by M. Minev, R. Zamanov, K. Stoyanov (Institute of Astronomy and NAO, Bulgarian Academy of Sciences)
https://www.astronomerstelegram.org/?read=16023
The flickering increased compared to the last published values (my work)
stronomerstelegram.org/?read=15916
and graph: http://www.astronomie-amateur.fr/DUAO/T ... ering.html

M. Minev+ conclude by the question: Does it mean that the super-active state is over?
The increase of the flickering coincides with the sudden fading of He II.

http://www.astronomie-amateur.fr/Erupti ... TCrB0.html updated
Christian Buil
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Re: T CrB before its new nova event

Post by Christian Buil »

Alpha evolution at high spectral resolution (instruments from 4 to 8 inch + Star'Ex HR, on ZWO AM5 mount) :

Image

C. Buil
etienne bertrand
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Re: T CrB before its new nova event

Post by etienne bertrand »

Un spectre de T Crb au LhiresIII
Image
Joan Guarro Flo
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Joined: Thu Nov 03, 2011 8:50 pm

Re: T CrB before its new nova event

Post by Joan Guarro Flo »

Hi there,

This is a T CrB graphics from the SMM Remote Observatory in this bad weather season.

Cheers, J. Guarro
Attachments
TCRB 20230603.png
TCRB 20230603.png (37.98 KiB) Viewed 3746 times
Guillaume Bertrand
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Location: Nantes

Re: T CrB before its new nova event

Post by Guillaume Bertrand »

Here's a new spectrum of T CrB with my little 72mm refractor. (A bit of a challenge ;)) In red, for comparison, a spectrum from a year ago.

Cheers,
Guillaume
Attachments
_tcrb_20220722_876_group_plot.png
Christian Buil
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Re: T CrB before its new nova event

Post by Christian Buil »

A high-resolution Star'Ex spectrum (R=19 000) made on June 13th from Antibes and like Guillaume B, using a small diameter, here an 80 mm Askar scope (model PHQ), all on an AM5 mount, and managed via ASIAir (except for the spectra storagel under Prism):

Image

Full observed range :

Image

The intensity of the Halpha line is still falling, while the star remains blocked at magnitude V=10. How far will this Halpha line go...

Christian Buil
Francois Teyssier
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Re: T CrB before its new nova event

Post by Francois Teyssier »

Yes, the spectrum returns to the pre-high state aspect: the continuum is dominated by the M4 III red giant. The emission lines becomes fainter (even if He II and He I are still present)
During the two last months, the EW grew a little bit according to orbital phase. But the global trend is decline.

First low res spectrum in the database, more than 10 years ago.
asdb_tcrb_20130217_146.png
asdb_tcrb_20130217_146.png (52.02 KiB) Viewed 3405 times
Guillaume's comparison shows the decline observed during the last months.
But a word a caution: the flux and profiles of the lines are strongly dependent of the orbital phase. Thus the most accurate comparison should use spectra acquired at the same orbital phase



This is a key point of the symbiotic stars monitoring: long term and high cadency observations can produce very valuable results
It needs much more abnegation than short observing campaigns.
This is my conception of the contribution of amateurs to the community (in fact exactly the same state of mind as in photometry since one and half century)
And it is very appreciated by number of professionnal teams working on eruptive stars.
Our T CrB dataset (more than 760 spectra in 10 years) is a treasure for the research (even if it raises more news question than it solves !)

I'm working on a presentation for the SAS 2013 symposium. It will be ready next week.

Bonne continuation! Keep on the very good job!
François
Attachments
asdb_tcrb_20230218_425.png
asdb_tcrb_20230218_425.png (43.55 KiB) Viewed 3242 times
Last edited by Francois Teyssier on Thu Jan 04, 2024 8:08 am, edited 1 time in total.
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