Speaker
Description
The Sun and Moon produce deep deficits in the nearly isotropic flux
of TeV cosmic rays measured at Earth. Observations of these
cosmic-ray deficits, or "shadows," can provide unique measurements
of the solar and Galactic environment. For example, the displacement
of the shadow of the Moon in the geomagnetic field allows for charge
discrimination of high-energy Galactic cosmic rays. The Sun shadow
varies strongly with the solar cycle, and multi-year measurements
enable precise tests of coronal magnetic field models. Moreover, the
Sun may also be a TeV gamma ray source due to interactions of
Galactic cosmic rays in its photosphere. The High Altitude Water
Cherenkov (HAWC) Observatory, a wide field-of-view detector of TeV
cosmic rays and gamma rays, performs unbiased high-statistics
measurements of the Sun and Moon each day. Using measurements of the
Moon shadow with two years of data from the complete HAWC array, we
will present strong limits on the flux of antiprotons above 1 TeV.
We will also present the first upper limits on the flux of gamma
rays above 1 TeV from the solar disk.
