title: Measurement of neutrino masses from relative velocities.
abstract: We present a new technique to measure neutrino masses using their flow field relative to dark matter. Present day streaming motions of neutrinos relative to dark matter and baryons are several hundred km/s, comparable with their thermal velocity dispersion. This results in a unique dipole anisotropic distortion of the matter-neutrino cross power spectrum, which is observable through the dipole distortion in the cross correlation of different galaxy populations. Such a dipole vanishes if not for this relative velocity and so it is a clean signature for neutrino mass. We estimate the size of this effect and find that current and future galaxy surveys may be sensitive to these signature distortions.
authors.affiliation: Key Laboratory for Computational Astrophysics, National Astronomical Observatories, Chinese Academy of Sciences, 20A Datun Road, Beijing 100012, China.
authors.forename: Hong-Ming
authors.initials: HM
authors.lastname: Zhu
authors.affiliation: Canadian Institute for Theoretical Astrophysics, 60 St. George Street, Toronto, Ontario M5S 3H8, Canada and Canadian Institute for Advanced Research, CIFAR Program in Gravitation and Cosmology, Toronto, Ontario M5G 1Z8, Canada.
authors.forename: Ue-Li
authors.initials: UL
authors.lastname: Pen
authors.affiliation: Key Laboratory for Computational Astrophysics, National Astronomical Observatories, Chinese Academy of Sciences, 20A Datun Road, Beijing 100012, China and Center of High Energy Physics, Peking University, Beijing 100871, China.
authors.forename: Xuelei
authors.initials: X
authors.lastname: Chen
authors.affiliation: Canadian Institute for Theoretical Astrophysics, 60 St. George Street, Toronto, Ontario M5S 3H8, Canada.
authors.forename: Derek
authors.initials: D
authors.lastname: Inman
authors.affiliation: Key laboratory for research in galaxies and cosmology, Shanghai Astronomical Observatory, Chinese Academy of Science, 80 Nandan Road, Shanghai 200030, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Yu