We provide a scenario in which a hidden U (1) gauge boson constitutes dark matter of the Universe and decays into the standard-model particles through a kinetic mixing with an U (1)B - L gauge boson. Interestingly, our model can naturally account for the steep rise in the positron fraction recently reported by PAMELA. Moreover, we find that due to the charge assignment of U (1)B - L, only a small amount of antiprotons are produced in the decay, which is also consistent with the PAMELA and other observational data.
|Number of pages||5|
|Journal||Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics|
|Publication status||Published - 2009 Mar 30|