X-ray Observations of Two Type Ia Supernovae with an H$\alpha$ Line in their Optical Spectrum

Vikram V. Dwarkadas

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arXiv · 2407.00279

X-ray Observations of Two Type Ia Supernovae with an H$\alpha$ Line in their Optical Spectrum

Vikram V. Dwarkadas

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Abstract

We report on Chandra X-ray observations of SN 2016jae and SN 2018cqj, both low luminosity Type Ia supernova that showed the presence of a H line in their early optical spectrum. No X-ray emission is detected at the location of either SN. Upper limits to the luminosity of up to 2 $\times 10^{40}\,$ erg s$^{-1}$ are calculated for each SN, depending on the assumed spectral model, temperature and column density. This luminosity is comparable to that of another low-luminosity Type Ia SN, SN 2018fhw, that was observed with Chandra. It is generally lower than upper limits calculated for Type Ia-CSM SNe observed in X-rays, and also below that of SN 2012ca, the only Type Ia-CSM SN to have been detected in X-rays. Comparisons are made to other Type Ia SN with a H line observed in X-rays. The observations suggest that while the density into which the SN is expanding may have been high at the time the H$\alpha$ line was detected, it had decreased considerably by the time of X-ray observations.

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Vikram V. Dwarkadas. 2024-06-29. X-ray Observations of Two Type Ia Supernovae with an H$\alpha$ Line in their Optical Spectrum. https://arxiv.org/abs/2407.00279

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