DW Cnc: a micronova with a negative superhump and a flickering spin

ABSTRACT Magnetic accreting white dwarfs in cataclysmic variables have been known to show bursts driven by different physical mechanisms; however, the burst occurrence is much rarer than in their non-magnetic counterparts. DW Cnc is a well-studied intermediate polar that showed a burst with a 4-mag amplitude in 2007. Here we report on a recent burst in DW Cnc observed by All-Sky Automated Survey for Supernovae that reached a peak luminosity of 6.6 $\times$ 10$^{33}$ erg s$^{-1}$, another 4 mag increase from its quiescent high state level. The released energy of the burst suggests that these are micronovae, a distinctive type of burst seen in magnetic systems that may be caused by a thermonuclear runaway in the confined accretion flow. Only a handful of systems, most of them intermediate polars, have a reported micronova bursts. We also report on the reappearance of the negative superhump of DW Cnc as shown by Transiting Exoplanet Satellite Survey and OPTICAM data after the system emerges from its low state and immediately before the burst. We further report on a new phenomenon, where the spin signal turns ‘on’ and ‘off’ on the precession period associated with the negative superhump, which may indicate pole flipping. The new classification of DW Cnc as a micronova as well as the spin variability show the importance of both monitoring known micronova systems and systematic searches for more similar bursts, to limit reliance on serendipitous discoveries.

Authors

Institutions

Publication Details

Journal
Monthly Notices of the Royal Astronomical Society
Published
2025-03-12
DOI
https://doi.org/10.1093/mnras/staf412
Citations
3
Primary Topic
Gamma-ray bursts and supernovae
Type
article
Field-Weighted Citation Impact
3.46

Funders

Controls
|||
ALL TIME
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
article

DW Cnc: a micronova with a negative superhump and a flickering spin

J V Hernández Santisteban, R. Michel, Noel Castro Segura, A. Sahu et al.
3 citations
Monthly Notices of the Royal Astronomical Society
Gamma-ray bursts and supernovae
3.46
article

DW Cnc: a micronova with a negative superhump and a flickering spin

J V Hernández Santisteban, R. Michel, Noel Castro Segura, A. Sahu, A. Castro, Liliana Altamirano-Dévora, P. Groot, Domitilla de Martino, John A. Paice, Z A Irving, Simone Scaringi, D. A. H. Buckley, Colin Littlefield, C. Knigge, J. Echevarría, D. Altamirano, M Veresvarska
article en
3 citations

Abstract

ABSTRACT Magnetic accreting white dwarfs in cataclysmic variables have been known to show bursts driven by different physical mechanisms; however, the burst occurrence is much rarer than in their non-magnetic counterparts. DW Cnc is a well-studied intermediate polar that showed a burst with a 4-mag amplitude in 2007. Here we report on a recent burst in DW Cnc observed by All-Sky Automated Survey for Supernovae that reached a peak luminosity of 6.6 $\times$ 10$^{33}$ erg s$^{-1}$, another 4 mag increase from its quiescent high state level. The released energy of the burst suggests that these are micronovae, a distinctive type of burst seen in magnetic systems that may be caused by a thermonuclear runaway in the confined accretion flow. Only a handful of systems, most of them intermediate polars, have a reported micronova bursts. We also report on the reappearance of the negative superhump of DW Cnc as shown by Transiting Exoplanet Satellite Survey and OPTICAM data after the system emerges from its low state and immediately before the burst. We further report on a new phenomenon, where the spin signal turns ‘on’ and ‘off’ on the precession period associated with the negative superhump, which may indicate pole flipping. The new classification of DW Cnc as a micronova as well as the spin variability show the importance of both monitoring known micronova systems and systematic searches for more similar bursts, to limit reliance on serendipitous discoveries.

Monthly Notices of the Royal Astronomical SocietyVol. 539(3)
Andrews University (US), St. Andrews University (US), Radboud University Nijmegen (NL), University of Cape Town (ZA), Universidad Autónoma de la Ciudad de México (MX), University of St Andrews (GB), Universidad Autónoma de Baja California (MX), Durham University (GB), University of the Free State (ZA), Astronomical Observatory of Capodimonte (IT), Ensenada Institute of Technology (MX), University of Warwick (GB), Bay Area Environmental Research Institute (US), South African Radio Astronomy Observatory (ZA), Astronomical Observatory (RS), University of Southampton (GB), Universidad Nacional Autónoma de México (MX)
National Aeronautics and Space Administration, Space Telescope Science Institute, Queen's University Belfast, National Research Foundation, Queen's University, Nuclear Safety and Security Commission, Universidad Nacional Autónoma de México, Science and Technology Facilities Council
Openalex Percentile: Top 9%
Gamma-ray bursts and supernovae
3.46
DOIOpen Access PDFOpenAlex
AI Navigator

Ask Laika to Summarize, Analyze, and Connect papers live on the map.

Summarize Papers & Methodologies

Extract key findings, datasets, and comparative methods across publications.

Benchmark Rankings & Visual Analytics

Rank top research institutions, authors, funders, topics, and journals by Field-Weighted Citation Impact (FWCI) and paper volume with instant charts.

Connect Distant Disciplines

Bridge topological clusters on the map to find hidden collaborative intersections.