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We report the discovery of high velocity candidates among RR~Lyrae starsfound in the Milky Way halo. We identified 9 RR~Lyrae stars with Galactocentricvelocities exceeding the local escape velocity based on the assumed Galaxypotential. Based on close examination of their orbits', we ruled out theirejection location in the Milky Way disk and bulge. The spatial distributionrevealed that seven out of 9 pulsators overlap with the position of theSagittarius stellar stream. Two out of these seven RR~Lyrae stars can betentatively linked to the Sagittarius dwarf spheroidal galaxy on the basis oftheir orbits. Focusing on the high-velocity tail of the RR~Lyrae velocitydistribution we estimate the escape velocity in the Solar neighborhood to be$v_{\rm esc}=512^{+94}_{-37}$\,km\,s$^{-1}$~($4$ to $12$\,kpc), and beyond theSolar neighborhood as $v_{\rm esc}=436^{+44}_{-22}$\,km\,s$^{-1}$~and $v_{\rmesc}=393^{+53}_{-26}$\,km\,s$^{-1}$~(for distances between $12$ to $20$\,kpcand $20$ to $28$\,kpc), respectively. We utilized three escape velocityestimates together with the local circular velocity to estimate the Milky Waymass. The resulting measurement $M_{\rm 200}=0.83^{+0.29}_{-0.16} \cdot10^{12}$\,M$_{\odot}$ falls on the lower end of the current Milky Way massestimates, but once corrected for the likely bias in the escape velocity(approximately $10$ percent increase of the escape velocity), our mass estimateyields $M_{\rm 200}=1.26^{+0.40}_{-0.22} \cdot 10^{12}$\,M$_{\odot}$, which isin agreement with estimates based on different diagnostics of the Milky Waymass. The MW mass within $20$\,kpc then corresponds to $M_{\rm MW} \left(r <20\,\text{kpc} \right)=1.9^{+0.2}_{-0.1} \times 10^{11}$\,M$_{\odot}$ withoutcorrection for bias, and $M_{\rm MW} \left(r < 20\,\text{kpc}\right)=2.1^{+0.2}_{-0.1} \times 10^{11}$\,M$_{\odot}$ corrected for a likelyoffset in escape velocities.

Milky Way archaeology using RR Lyrae and type II Cepheids II. High velocity RR Lyrae stars, and mass of the Milky Way