THO3LR03
BNL, Upton, Long Island, New York, USA
To compensate for the beam-beam effects from the proton-proton interactions at the two interaction points in the Relativistic Heavy Ion Collider (RHIC), two electron lenses (e-lenses) have been installed and commissioned in 2014. In this report, the physics of electron lens is briefly introduced, followed by the electron lens hardware and electron beam commissioning results in 2014 RHIC run. Although in 2014, RHIC is operating with gold and 3He beams, and the luminosity is not limited by head on beam-beam interactions, we still aligned the electron beam with the hadron beam to get the first experience with the electron-hadron beam interaction. The demonstration of electron and gold beam overlap has been achieved via electron backscattered detector, as well as the demonstration of electron beam parameters that are sufficiently stable to have no negative impact on the gold beam life time. With the experience of using electron lens on hadron beam, head on beam-beam compensation can be commissioned in the following year with proton beams, with a lattice which phase advance has a multiple of 180 degrees between the beam-beam interaction and electron lens locations.
