3 research outputs found
SN 2021gno: a Calcium-rich transient with double-peaked light curves
We present extensive ultraviolet (UV) and optical photometric and optical
spectroscopic follow-up of supernova (SN)~2021gno by the "Precision
Observations of Infant Supernova Explosions" (POISE) project, starting less
than two days after the explosion. Given its intermediate luminosity, fast
photometric evolution, and quick transition to the nebular phase with spectra
dominated by [Ca~II] lines, SN~2021gno belongs to the small family of
Calcium-rich transients. Moreover, it shows double-peaked light curves, a
phenomenon shared with only four other Calcium-rich events. The projected
distance from the center of the host galaxy is not as large as other objects in
this family. The initial optical light-curve peaks coincide with a very quick
decline of the UV flux, indicating a fast initial cooling phase. Through
hydrodynamical modelling of the bolometric light curve and line velocity
evolution, we found that the observations are compatible with the explosion of
a highly-stripped massive star with an ejecta mass of and a
Ni mass of . The initial cooling phase (first light
curve peak) is explained by the presence of an extended circumstellar material
comprising with an extension of .
We discuss if hydrogen features are present in both maximum-light and nebular
spectra, and its implications in terms of the proposed progenitor scenarios for
Calcium-rich transients.Comment: 21 pages, 13 figures, accepted for publication in MNRA
SN 2021gno: a calcium-rich transient with double-peaked light curves
We present extensive ultraviolet (UV) and optical photometric and optical spectroscopic follow-up of supernova (SN) 2021gno by the 'Precision Observations of Infant Supernova Explosions' (POISE) project, starting less than 2 d after the explosion. Given its intermediate luminosity, fast photometric evolution, and quick transition to the nebular phase with spectra dominated by [Ca ii] lines, SN 2021gno belongs to the small family of Calcium-rich transients. Moreover, it shows double-peaked light curves, a phenomenon shared with only four other Calcium-rich events. The projected distance from the centre of the host galaxy is not as large as other objects in this family. The initial optical light-curve peaks coincide with a very quick decline of the UV flux, indicating a fast initial cooling phase. Through hydrodynamical modelling of the bolometric light curve and line velocity evolution, we found that the observations are compatible with the explosion of a highly stripped massive star with an ejecta mass of and a 56Ni mass of 0.024 M⊙. The initial cooling phase (first light-curve peak) is explained by the presence of an extended circumstellar material comprising ∼ with an extension of. We discuss if hydrogen features are present in both maximum-light and nebular spectra, and their implications in terms of the proposed progenitor scenarios for Calcium-rich transients