Monitoring T CrB
Active Dates: Oct. 18, 2024 – Oct. 31, 2026
Abstract:
The AAVSO and multiple astronomers request ongoing monitoring of the recurrent nova T CrB 1) to alert the astronomical community as soon as T CrB begins its eruption, and 2) to continue to build its multicolor light curve prior to, during, and after the anticipated eruption. Observations with all filters, as well as visual observations, are requested. Spectroscopy is also requested. Observations should be reported to the AAVSO International Database (AID) or AAVSO Spectroscopy Database (AVSpec) as soon as possible after making them. Discussion re T CrB has been moved from the old (now archived) AAVSO forum to the AAVSO forum created in October 2024 for this observing campaign.
Justification:
Valuable and important information on what to do now regarding observing T CrB and what to do when it erupts is given in the AAVSO blog post: "What to do during the eruption of T CrB" ( https://www.aavso.org/blog/what-do-during-eruption-t-crb). See below for a link to creating finder charts with comparison stars and to accessing pre-made charts of T CrB. Background information on T CrB and a link to the YouTube video of an AAVSO webinar on T CrB may be found here: https://www.aavso.org/news/t-crb-pre-eruption-dip
Requested Data Types:
Spectroscopy, Photometry
Targets
| Name | Magnitude | Variability Type | Photometry Notes | Spectroscopy Notes |
|---|---|---|---|---|
| T CrB | 2.00 | NR+ELL |
Cadence: Custom Precision: 100 |
Cadence: Custom Resolution: 1000 Desired SNR: 100 |
Spectroscopy Lines:
H-beta (4861.0 Å), H-alpha (6563.0 Å)
Photometry Filters:
U (Johnson), B (Johnson), V (Johnson), R (Cousins), I (Cousins), u (Sloan), g (Sloan), r (Sloan), i (Sloan), z (Sloan), Other (Please Specify)
Comparison Stars:
Finder charts with comparison stars for T CrB may be created using the AAVSO Variable Star Plotter (https://apps.aavso.org/vsp). Pre-made charts for T CrB may be downloaded from here: https://www.aavso.org/t-crb-finder-charts
Co-Authorship
Observers are not eligible for co-authorship.
Additional Observer Input:
PHOTOMETRY: Other filters include unfiltered reduced to a V zero point (CV), unfiltered reduced to an Rc zeropoint (RC), and visual. Nightly observations are requested prior to the eruption. Once the eruption begins, several observations per night are requested until after the eruption is over and T CrB has returned to minimum, or until a different cadence is requested. CAUTION: CCD and CMOS observers need to be extremely careful not to saturate their detectors, especially when T CrB is very bright (see the recommendations given in the "What to do during the eruption of T CrB" blog post linked to above). SPECTROSCOPY: Prior to the eruption, low resolution observations a few times per week covering the entire spectrum are requested. During the eruption the AAVSO will request both low-resolution observations covering the entire spectrum as well as high-resolution observations of several near-UV and optical emission lines (for example, [Ne III] at 3869 and 3967Å; the Calcium Triplet at 8498, 8542, and 8662Å; and Hɑ at 6563Å). Observations of a given spectroscopic line / region should be collected 3-4 times per night during the first two weeks of the eruption and nightly thereafter until the end of the eruption.
Additional Submission Location:
No other submission locations are requested.
Notes:
No public notes