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We present here the precise wavelength calibration of a high-resolutionspectrum using Uranium (U) lines in the wavelength range of 3809 - 6833 \AA\for precision radial velocity measurements for exoplanet detection or relatedastrophysical sciences. We identify 1540 well-resolved U lines from ahigh-resolution (R=67,000) spectrum of the uranium-argon hollow cathode lamp(UAr HCL) using PARAS spectrograph in the aforesaid wavelength range. Wecalculate the neutral and first allowed transitions (Ritz wavelength) of U fromits known energy levels and compare them with our observed central wavelengths.We measure an offset of -0.15 m\AA\space in our final U line list. The linelist has an average measurement uncertainty of 15 m s$^{-1}$ (0.013 pixels or0.28 m\AA). We included these lines to the PARAS data analysis framework toperform the wavelength calibration and then calculate the multi-order RadialVelocity (RV) of PARAS spectra. The typical dispersion of residuals around thewavelength solution of a UAr spectrum, using U lines, is found to be 0.8m\AA\space($\sim$45 m s$^{-1}$). With the use of this line list, we present ourresults for the precision RV of an on-sky source (A RV standard star), and anoff-sky source (A HCL) observed with PARAS along with UAr HCL. We measure thedispersion in absolute drift difference between two fibers (inter-fiber drift)for a span of 6.5 hours to be 88 cm s$^{-1}$, and the RV dispersion(${\sigma_{RV}}$) for a RV standard star, HD55575 over the course of $\sim$450days to be 3.2 m s$^{-1}$. These results are in good agreement with theprevious ones measured using the ThAr HCL. It proves that the ThAr HCL with$\sim$ 99\% pure-Th are replaceable with the UAr HCL for the wavelengthcalibration of the high-resolution spectrographs such as PARAS (R $\leq$67,000) to achieve a RV precision of 1-3 m s$^{-1}$ in the visible region.

Precision wavelength calibration for Radial Velocity measurements using Uranium lines between 3800-6900 \AA