Persistent flickering of T CrB during the high activity state pre-nova outburst phase
ATel #15916; S. N. Shore (Univ. Pisa), F. Teyssier ARAS Group)
on 28 Feb 2023; 12:44 UT
Distributed as an Instant Email Notice Novae
Credential Certification: S. N. Shore (shore@df.unipi.it)
Subjects: Optical, Cataclysmic Variable, Nova, Variables
Referred to by ATel #: 16023
In 2015, the recurrent nova T Coronae Borealis entered an active state (Ilkiewicz et al. 2016) that is likely preceding its next outburst (Schaefer 2019, Luna etal. 2020). On 2023 Jan. 14, we detected flickering of T CrB in B band photometry at the primary focus of the 1 meter telescope Omicron of the Observatory C2PU (Calern, France). A total of 525 images (individual exposure time of 10s) were obtained on 2023 Jan. 14 from 03:05 to 04:59 UTC. The total amplitude detected was 0.125+/- 0.01 mag. This observation confirms that flickering persists during the active state, but at a lower level (see ATel #2586, ATel #8675). The amplitude is greater than for the 2016 observations, the brightness in B has decreased (delta B approx. +0.37). The cadence permitted the detection of very rapid events (brightening and dimmings) with durations from 4 min to 1 min with respective amplitudes of about 0.03 to 0.01 mag. The summary is given in the table, the plots are accessed at the associated URL (below).
Table 1. Flickering of T CrB
min max average stdev typical error
[mag] [mag] [mag] [mag] [mag]
11.041 11.166 11.113 0.028 0.010
This study was performed in the context of the training DUAO provided by Université Nice Côte d'Azur MAUCA (France)
Plots of B flickering in T CrB
