J/A+A/704/A135 Optical photometry of SN 2020aeuh (Tsalapatas+, 2025)
A thermonuclear supernova interacting with hydrogen- and helium-deficient
circumstellar material. SN 2020aeuh as a SN Ia-CSM-C/O?
Tsalapatas K., Sollerman J., Chiba R., Kool E., Johansson J., Rosswog S.,
Schulze S., Moriya T.J., Andreoni I., Brink T.G., Chen T.X., Covarrubias S.,
De K., Dimitriadis G., Filippenko A.V., Fremling C., Gangopadhyay A.,
Maguire K., Mo G., Sharma Y., Sravan N., Terwel J.H., Yang Y.
<Astron. Astrophys. 704, A135 (2025)>
=2025A&A...704A.135T 2025A&A...704A.135T (SIMBAD/NED BibCode)
ADC_Keywords: Supernovae ; Photometry, ugriz ; Optical
Keywords: supernovae: general - supernovae: individual: SN 2020aeuh -
supernovae: individual: SN 2020eyj
Abstract:
Identifying the progenitors of thermonuclear supernovae (Type Ia
supernovae; SNe Ia) remains a key objective in contemporary astronomy.
The rare subclass of SNe Ia-CSM that interacts with circumstellar
material (CSM) allows for studies of the progenitor's environment
before explosion, and generally favours single-degenerate progenitor
channels. The case of SN Ia-CSM PTF11kx clearly connected
thermonuclear explosions with hydrogen-rich CSM-interacting events,
and the more recent SN 2020eyj connected SNe Ia with helium-rich
companion progenitors. Both of these objects displayed delayed CSM
interaction which established their thermonuclear nature. Here we
present a study of SN2020aeuh, a Type Ia-CSM with delayed interaction.
We analyse photometric and spectroscopic data that monitor the
evolution of SN2020aeuh and compare its properties with those of
peculiar SNe Ia and core-collapse SNe.
At early times, the evolution of SN2020aeuh resembles a slightly
overluminous SN∼Ia. Later, the interaction-dominated spectra develop
the same pseudocontinuum seen in Type Ia-CSM PTF11kx and SN 2020eyj.
However, the later-time spectra of SN2020aeuh lack hydrogen and helium
narrow lines. Instead, a few narrow lines could be attributed to
carbon and oxygen. We fit the pseudobolometric light curve with a
CSM-interaction model, yielding a CSM mass of 1-2M☉.
We propose that SN2020aeuh was a Type Ia supernova that eventually
interacted with a dense medium which was deficient in both hydrogen
and helium.
Whereas previous SNe Ia-CSM constitute our best evidence for
nondegenerate companion progenitors, the CSM around SN2020aeuh is more
difficult to understand. We include a hydrodynamical simulation for a
double-degenerate dynamical collision to showcase that such a
progenitor scenario could produce significant amounts of hydrogen-poor
CSM, although likely not as much as the inferred CSM mass around
SN2020aeuh. It is clear that SN2020aeuh challenges current models for
stellar evolution leading up to a SN Ia explosion.
Description:
Optical photometry of SN 2020aeuh, in observed magnitudes. Phase is
relative to ZTF first detection, in rest-frame days.
Objects:
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RA (2000) DE Designation(s)
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12 35 51.85 +37 42 12.53 SN 2020aeuh = ATLAS 20bkbb
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea1.dat 49 662 Optical photometry of SN 2020aeuh
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Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
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1- 10 F10.4 d MJD Time in MJD
13- 18 F6.2 d Phase Phase relative to first detection
20 A1 --- Filter [gri co] Optical Filters
23- 27 F5.2 mag mag ? Magnitude in Filter in the AB system
30- 34 F5.2 mag e_mag ? Magnitude in Filter error
36- 40 F5.2 mag maglim ? Limiting magnitude
42- 49 A8 --- Tel Telescope + instrument
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Acknowledgements:
Konstantinos Tsalapatas, konstantinos.tsalapatas(at)astro.su.se
(End) Patricia Vannier [CDS] 01-Oct-2025