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arXiv · 2507.11647

X-ray Measurements of $^{44}$Ti in Four Supernova Remnants

Tyler E. Hanover·Mark D. Leising
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Abstract

We present the results of a search for scandium K$_\alpha$ X-ray fluorescence resulting from $^{44}$Ti electron capture decay in four young supernova remnants. We analyzed archival XMM-Newton data from Tycho's SNR, Kepler's SNR, Cassiopeia A, and SN 1987A. We fit the X-ray spectra in regions of interest with up to four components, thermal and power-law, as needed to fit the spectrum, and add a gaussian to test for extra Sc emission. While all require the line with modest confidence, none represent definitive detections on their own, and all are consistent with previous gamma-ray detections or limits on the $^{44}$Ti mass.

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Tyler E. Hanover, Mark D. Leising. 2025-07-15. X-ray Measurements of $^{44}$Ti in Four Supernova Remnants. https://doi.org/10.3847/1538-4357%2Fadec8b

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