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The brightness of the tip of the red-giant branch (TRGB) allows one toconstrain novel energy losses that would lead to a larger core mass at heliumignition and thus to a brighter TRGB than expected by standard stellar models.The required absolute TRGB calibrations strongly improve with reliablegeometric distances that have become available for the galaxy NGC 4258 thathosts a water megamaser and to the Large Magellanic Cloud based on 20 detachedeclipsing binaries. Moreover, we revise a previous TRGB calibration in theglobular cluster $\omega$ Centauri with a recent kinematical distancedetermination based on Gaia DR2 data. All of these calibrations have similaruncertainties and they agree with each other and with recent dedicated stellarmodels. Using NGC 4258 as the cleanest extra-galactic case, we thus find anupdated constraint on the axion-electron coupling of $g_{ae}<1.6\times10^{-13}$and $\mu_\nu<1.5\times10^{-12}\mu_{\rm B}$ (95\% CL) on a possible neutrinodipole moment, whereas $\omega$ Centauri as the best galactic target providesinstead $g_{ae}<1.3\times10^{-13}$ and $\mu_\nu<1.2\times10^{-12}\mu_{\rm B}$.The reduced observational errors imply that stellar evolution theory andbolometric corrections begin to dominate the overall uncertainties.

Axion and neutrino bounds improved with new calibrations of the tip of the red-giant branch using geometric distance determinations