The 2024 eruption of the Recurrent Nova LMC 1968 as caught by Swift
ATel #16752; M. J. Darnley (LJMU), N. P. M. Kuin (MSSL/UCL), K. L. Page (U. Leicester)
on 6 Aug 2024; 12:42 UT
Credential Certification: Matt Darnley (matt_darnley@icloud.com)
Subjects: Ultra-Violet, Nova, Transient
The Large Magellanic Cloud Recurrent Nova LMC 1968 (LMC V1341) has previously been seen in eruption in 1968, 1990 (Shore et al. 1991, ApJ, 370, 193), 2002, 2010 (Mróz et al. 2014, MNRAS, 443, 784), 2016 (Kuin et al. 2020, MNRAS, 491, 655), and 2020. Following the 2020 eruption, a recurrence period of four years was proposed (ATel #13731).
The Neil Gehrels Swift Observatory has been observing Nova LMC 1968 with a monthly cadence since the end of the 2020 eruption. The most recent observation occurred on 2024 August 1, comprising two snapshots of data taken about 16 hours apart.
The nova was still in quiescence during the first snapshot, but clearly in eruption during the latter.
The in-eruption count rate in the UVOT filters exceeded limits for aperture photometry, so the readout-streak was used (Page et al. 2013, MNRAS, 436, 1684):
Date (UT) UVOT (mag)
2024Aug01T04:19 m2 = 18.87 ± 0.16
2024Aug01T04:33 w1 = 18.19 ± 0.09
2024Aug01Y19:59 m2 = 9.9 ± 0.1
2024Aug01T20:12 w1 = 10.0 ± 0.1
No X-ray emission was detected during either snapshot, down to an upper limit of 0.004 count/s for the combined data, or 0.009 count/s at the time of the second snapshot.
As such, it seems that the 2024 eruption of Nova LMC 1968 occurred between 4:33 and 19:59 (UT) on 2024 August 1. There was no evidence for an X-ray flash within the sensitivity range of Swift. Based on quiescent monitoring of the nova, the recurrence period is 4 years.
Follow-up observations, including spectroscopy are most welcome.
