We present high-resolution measurements of $4f–3d$ x-ray transitions in Cr-like tungsten ions conducted at Shanghai Electron Beam Ion Trap (EBIT). These previously unresolved lines within the $5.195–5.260\AA$ wavelength range are relevant to tokamak plasma diagnostics. High-resolution measurements using a flat Si (111) crystal spectrometer yielded experimental wavelengths with an accuracy of approximately 40 ppm. The agreement between the measured spectra and those theoretically simulated from Flexible Atomic Code calculations and collisional-radiative modeling supported the line identifications. For the seven identified lines, the average difference between experimental and theoretical wavelengths is around 132 ppm. In Maxwellian fusion plasmas, these Cr-like ${\mathrm{W}}^{50+}$ lines are predicted to maintain a stable profile similar to the profile observed in the EBIT. Additionally, some emissions from higher-charged tungsten were observed but remain unassigned. These measurements provide valuable benchmarks for both fusion plasma diagnostics and the validation of challenging atomic structure calculations of highly charged ions with open $3d$ subshell.

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• Atomic spectra
• Electron correlation calculations for atoms & ions
• Electronic transitions
• Fine & hyperfine structure
• Trapped ions
• Atom & ion trapping & guiding
• Configuration interaction
• X-ray diffraction