The Owens Valley Radio Observatory

The Owens Valley Radio Observatory, located in the stunning Owens Valley, California, is the home of several Caltech-operated telescopes performing experiments in the fields of blazar jet physics, the interstellar medium, and the cosmic microwave background. It also provides the infrastructure to support the research being performed at the nearby CARMA array.

The 40m telescope is currently monitoring the 15 GHz flux densities of more than 1400 blazars: active galactic nuclei jets aimed directly at us. Each source is being observed at least twice a week. These measurements, interesting in their own right, are being correlated with brightnesses across the EM spectrum (and gamma radiation monitored by NASA's Fermi Gamma-Ray Space Telescope in particular) in order to explain the emission mechanisms in the highly-relativistic blazar jets. Further, the observatory is designing and building a new broadband receiver to increase the sensitivity of the telescope and measure the polarization of the radiation. The 40m telescope is also being used for a transient monitoring program which will soon employ the two 27m telescopes as well. The principle focus of the program is to study long-duration transients.

The C-Band All Sky Survey (CBASS) is now underway in an effort to map the polarized synchrotron emission from the Milky Way. The map will help astronomers to understand the Galactic magnetic field while aiding in the foreground subtraction from CMB maps. Such subtraction will enable OVRO to measure the CMB's elusive B-mode polarization, a relic of the inflationary period. The map will be made at 5 GHz using one of the 6m telescopes in Owens Valley and a 7.6m telescope in South Africa. OVRO has played a key role in the design and assembly of this experiment.

The Ku-Band Experiment (KuBE) is a proposed complement to the CBASS experiment which will be done at 15 GHz. A key difference is that KuBE is expected to be sensitive to the anomalous Galactic emission, probably due to spinning dust grains in the interstellar medium and discovered just last decade at OVRO. Caltech is leading the design and fabrication of this experiment, which will likely use a 6m dish.

Text maintained by Walter Max-Moerbeck <wmax [at]>