The present gravitational wave detection effort

Gravitational radiation offers a new non-electromagnetic window through which to observe the universe. The LIGO and Virgo Collaborations have completed a first joint data run with unprecedented sensitivities to gravitational waves. Results from searches in the data for a variety of astrophysical sources are presented. A second joint data run with improved detector sensitivities is underway, and soon major upgrades will be carried out to build Advanced LIGO and Advanced Virgo with expected improvements in event rates of more than 1000. In parallel there is a vigorous effort in the radio pulsar community to detect nHz gravitational waves via the timing residuals in an array of pulsars at different locations in the sky.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/85430/1/jpconf10_203_012002.pd

Dielectric measurements on high-Q ceramics in the microwave region

The postresonator method proposed by Hakki and Coleman for the measurement of dielectric properties of solids in the microwave region is reexamined. Based on the experiments performed around 10 GHz, the limitations of the method in loss determination for materials with tan delta < 5 x 10(-4) are outlined. Alternative techniques for studying high-Q materials are described. Loss measurements performed on well-prepared ceramics have been used to draw comparisons among these techniques. Some of the experimental findings are new and are reported for the first time

DiP230: Dielectric-Spectroscopy of Some Ba(B'1/2b''1/2)O3 Complex Perovskites in the 10(11)-10(14)Hz Range

Five Ba(B'1/2B1/2'')O3 ceramic compounds (B' = Y3+, Gd3+, Nd3+, In3+; B'' = Ta and B' = Mg2+; B'' = W6+) have been prepared to investigate the origin of microwave losses. Infrared reflectivity and submillimetre transmission measurements as well as low-frequency dielectric measurements were performed and evaluated. An attempt was undertaken to divide the submillimetre losses into intrinsic lattice losses (multiphonon absorption) proportional to temperature and extrinsic temperature independent loss contributions