These particles are found in cosmic rays, where the anomalously large fraction observed by PAMELA in
These particles are found in cosmic rays, where the anomalously large fraction observed by PAMELA in 2008 has led scientists to speculate a primary source other than the interstellar medium. Applications of these particles include a namesake emission tomography that detects the gamma rays they emit upon annihilation. Discovered by Anderson in 1932, one of these particles and a neutrino are among the products of beta positive decay and Dirac theorized their existence as negative energy solutions to his namesake equation. For 10 points, name these positively-charged fermions, antiparticles of electrons.
These particles are found in cosmic rays, where the anomalously large fraction observed by PAMELA in 2008 has led scientists to speculate a primary source other than the interstellar medium.