X-ray spectroscopy mass constraints on V1674 Her: the fastest nova does not have a near-Chandrasekhar white dwarf

Tekeba Olbemo, Manel Errando, Andrea Gokus

V1674 Her (Nova Her 2021) is the fastest classical nova ever recorded, with an optical decline time of $t_2\sim 1$ day, typically interpreted as evidence for a white dwarf mass cl…