Speaker
Yorito Yamaguchi
Description
A hypothetical *U*(1) gauge field has been introduced to explain several
experimental results that the Standard Model (SM) can not describe,
such as the high energy positron excess in cosmic rays, the muon g-2 anomaly
and so on. The hypothetical *U*(1) field is considered to very weakly couple
with SM, and its gauge boson called as a 'dark photon' mixes in ordinary
photons as a result.
The PHENIX experiment has a good capability to measure low mass electron pairs
with a good mass resolution. We have conducted a search for elecron pairs possibly
showing up from dark photons within Dalitz decays of $\pi^{0}$ and $\eta$. An upper limit
of the dark photon mixing strength with ordinary photons has been obtained for
30<$m_{ee}$<90 MeV/c$^{2}$. Combining with other experimental results, the possibility of
explanation by the dark photon for the 3.6 sigma deviation of the measured muon
g-2 value from the SM calculations was excluded.
We will present our latest result on the dark photon search and discuss a possibility
for future light dark matter searches with heavy ion collisions as well.
| On behalf of collaboration: | PHENIX |
|---|
Author
Yorito Yamaguchi
