In this work we are reporting on the measurement of the proton-air inelastic cross section $sigma^{rm inel}_{rm p-air}$ using the Telescope Array (TA) detector. Based on the measurement of the $sigma^{rm inel}_{rm p-air}$ the proton-proton cross sect
ion $sigma_{rm p-p}$ value is also determined at $sqrt{s} = 95_{-8}^{+5}$ TeV. Detecting cosmic ray events at ultra high energies with Telescope Array enables us to study this fundamental parameter that we are otherwise unable to access with particle accelerators. The data used in this report is the hybrid events observed by the Middle Drum fluorescence detector together with the surface array detector collected over five years. The value of the $sigma^{rm inel}_{rm p-air}$ is found to be equal to $567.0 pm 70.5 [{rm Stat.}] ^{+29}_{-25} [{rm Sys.}]$ mb. The total proton-proton cross section is subsequently inferred from Glauber Formalism and Block, Halzen and Stanev QCD inspired fit and is found to be equal to $170_{-44}^{+48} [{rm Stat.}] _{-17}^{+19} [{rm Sys.}] $mb.
In this paper we report the first observation in the Southern hemisphere of an energy dependence in the Galactic cosmic ray anisotropy up to a few hundred TeV. This measurement was performed using cosmic ray induced muons recorded by the partially de
ployed IceCube observatory between May 2009 and May 2010. The data include a total of 33$times 10^{9}$ muon events with a median angular resolution of $sim3^{circ}$ degrees. A sky map of the relative intensity in arrival direction over the Southern celestial sky is presented for cosmic ray median energies of 20 and 400 TeV. The same large-scale anisotropy observed at median energies around 20 TeV is not present at 400 TeV. Instead, the high energy skymap shows a different anisotropy structure including a deficit with a post-trial significance of -6.3$sigma$. This anisotropy reveals a new feature of the Galactic cosmic ray distribution, which must be incorporated into theories of the origin and propagation of cosmic rays.
