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arXiv · 2309.11563

From Out of the Blue: Swift Links 2002es-like, 2003fg-like, and Early-Time Bump Type Ia Supernovae

W. B. Hoogendam·B. J. Shappee·P. J. Brown·M. A. Tucker·C. Ashall·A. L. Piro
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Abstract

We collect a sample of 42 SNe Ia with Swift UV photometry and well-measured early-time light curve rises and find that 2002es-like and 2003fg-like SNe Ia have different pre-peak UV color evolutions compared to normal SNe Ia and other spectroscopic subtypes. Specifically, 2002es-like and 2003fg-like SNe Ia are cleanly separated from other SNe Ia subtypes by UVM2-UVW1>=1.0~mag at 10 days prior to B-band maximum. Furthermore, the SNe Ia that exhibit non-monotonic bumps in their rising light curves, to date, consist solely of 2002es-like and 2003fg-like SNe Ia. We also find that SNe Ia with two-component power-law rises are more luminous than SNe Ia with single-component power-law rises at pre-peak epochs. Given the similar UV colors, along with other observational similarities, we discuss a possible progenitor scenario that places 2002es-like and 2003fg-like SNe Ia along a continuum and may explain the unique UV colors, early-time bumps, and other observational similarities between these objects. Ultimately, further observations of both subtypes, especially in the near-infrared, are critical for constraining models of these peculiar thermonuclear explosions.

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W. B. Hoogendam, B. J. Shappee, P. J. Brown, M. A. Tucker, C. Ashall, A. L. Piro. 2023-09-20. From Out of the Blue: Swift Links 2002es-like, 2003fg-like, and Early-Time Bump Type Ia Supernovae. https://doi.org/10.3847/1538-4357%2Fad33ba

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