Background: Contemporary stopping powers for $fp$-shell nuclei slowing in tantalum can differ by a factor of 2 from the 1963 Lindhard, Scharff, and Schiøtt (LSS) theory [Mat. Fys. Medd. Dan. Vidensk Selsk. 33, no. 14 (1963)] used in Doppler-shift attenuation method (DSAM) lifetime measurements dating back to the 1970s. In recent work by Woodside et al. [Phys. Rev. C 113, 044306 (2026)], it was found that anomalously high collectivity in the $4_1^{+}\to 2_1^{+}$ transition of ${}^{58}\mathrm{Fe}$ given in the Evaluated Nuclear Structure Data File (ENSDF), Nesaraja et al. [Nucl. Data Sheets 111, 897 (2010)] could be traced back as largely due to the use of these historical stopping powers in the Doppler-shift lifetime measurements. Satisfactory agreement with shell-model calculations was obtained from a reanalysis of the 1978 DSAM measurement of Bolotin et al. [Nucl. Phys. A 311, 75 (1978)] once the stopping powers were replaced by up-to-date values.

Purpose: The DSAM measurement on ${}^{54}\mathrm{Cr}$ by the same group, Stuchbery et al. [Nucl. Phys. A 337, 1 (1980)], which used the same experimental methods and procedures, is reexamined.

Method: The computer code used in the original DSAM analysis has been rebuilt and upgraded with the capacity to use contemporary stopping powers. Reduced $E2$ transition strengths derived from the revised lifetimes are compared with shell-model calculations.

Results: The impact of revised stopping powers on the excited-state lifetimes depends on the relative contributions of nuclear and electronic stopping powers. It is primarily the electronic stopping powers that differ from LSS values. Hence, the magnitude of the change in lifetime depends on the lifetime itself. In the present case, the lifetimes increase by 16% to 27%, with the larger increase generally corresponding to shorter lifetimes where electronic stopping dominates.

Conclusions: Revised lifetimes, based on current stopping powers, imply $B\left(E2\right)$ transition rates between states up to the $6_1^{+}$ state in ${}^{54}\mathrm{Cr}$ that compare well with shell-model calculations using the GXFP1A interaction. Better agreement is obtained with the effective charges recently proposed by Ogunbeku et al. [Phys. Rev. Lett. 135, 072501 (2025)], namely $e_{\pi }=1.3$ and $e_{\nu }=0.45$, than with the standard $e_{\pi }=1.5$ and $e_{\nu }=0.5$. The lifetime data together with branching ratios and the shell-model calculations strongly suggest revision of the spins assigned to the levels at 3.786 [currently ${\left(4\right)}^{+}$] and 4.043 MeV (currently $5^{+}$). These levels are suggested to be the $5_1^{+}$ and $6_2^{+}$ states, respectively.

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• Electromagnetic transitions
• Lifetimes & widths
• Nuclear spin & parity
• Nuclear structure & decays
• Nuclear transition rates
• 39 ≤ A ≤ 58
• Shell model