OTR imaging of intense 120 GeV protons in the NuMI beamline at fnal

An Optical Transition Radiation (OTR) detector has been installed in the Fermilab NuMI proton beamline, which operates at beam powers of up to -350 kW, to obtain real-time, spill-by-spill beam profiles for neutrino production. As part of the Run II collider plan and the NuMI neutrino program, a series of OTR detectors were designed, constructed and installed in various beamlines at Fermilab. NuMI OTR images of 120 GeV protons for 13 beam intensities up to 4.1times10¹³ at a spill rate of 0.5 Hz and small transverse beam size of ~1 mm (sigma) are presented here. Beam profiles are extracted from the OTR images and compared with an adjacent secondary- electron emission (SEM) monitor. The OTR detector provides two-dimensional beam shape, such as ellipticity and tilt, as well as beam centroid and beam intensity information. In addition, the response of the OTR detector over time is examined to look for signs of foil aging.