Neutrino Masses, Dark Energy and the Gravitational Lensing of Pregalactic HI

Understand

We study the constraints which the next generation of radio telescopes could place on the mass and number of neutrino species by studying the gravitational lensing of high redshift 21 cm emission in combination with wide-angle surveys of galaxy lensing.

• We use simple characterizations of reionization history and of proposed telescope designs to forecast the constraints and detectability threshold for neutrinos.
• It is found that the degeneracy between neutrino parameters and dark energy parameters is significantly reduced by incorporating 21 cm lensing.
• The combination of galaxy and 21 cm lensing could constrain the sum of the neutrino masses to within ~ 0.04 eV and the number of species to within ~ 0.1.