[Yang, X. J.
; Lu, F. J.] Chinese Acad Sci, Ctr Particle Astrophys, Inst High Energy Phys, Beijing 100049, Peoples R China
; [Yang, X. J.
; Chen, L.] Beijing Normal Univ, Dept Astron, Beijing 100875, Peoples R China
; [Tsunemi, H.] Osaka Univ, Dept Earth & Space Sci, Grad Sch Sci, Osaka 5600043, Japan
We performed aCr-Kemission line survey in young supernova remnants (SNRs) with the Chandra archival data. Our sample includes W49B, Cas A, Tycho, andKepler. We confirmed the existence of the Cr line in W49B and discovered this emission line in the other three SNRs. The line center energies, equivalent widths (EWs), and fluxes of the Cr lines are given. The Cr in Cas A is in a high ionization state, while that in Tycho and Kepler is in a much lower one. We find a good positive correlation between Cr and Fe line center energies, suggesting a common origin of Cr and Fe in the nucleosynthesis, which is consistent with the theoretical predictions. We propose that the EW ratio between Cr and Fe can be used as a supplementary constraint on the progenitors' properties and the explosion mechanism.