Friday·February 23, 2018

Neutron stars exclude light dark baryons

David McKeen🇺🇸 · Ann E. Nelson🇺🇸 · Sanjay Reddy🇺🇸 · Dake Zhou🇺🇸

Exotic new particles carrying baryon number and with mass of order the nucleon mass have been proposed for various reasons including baryogenesis, dark matter, mirror worlds, and the neutron lifetime puzzle. We show that the existence of neutron stars with mass greater than 0.7 $M_{\odot }$ places severe constraints on such particles, requiring them to be heavier than 1.2 GeV or to have strongly repulsive self-interactions.