We have detected sub-TeV gamma-ray emission from the direction of the Galactic center (GC) using the CANGAROO-II Imaging Atmospheric Cerenkov Telescope. We detected a statistically significant excess at energies greater than 250 GeV. The flux was 1 order of magnitude lower than that of the Crab Nebula at 1 TeV with a soft spectrum proportional to . The signal centroid is consistent with the GC direction, and the Ϫ4.6‫5.0ע‬E observed profile is consistent with a pointlike source. Our data suggest that the GeV source 3EG J1746Ϫ2851 is identical to this TeV source, and we study the combined spectra to determine the possible origin of the gammaray emission. We also obtain an upper limit on the cold dark matter density in the Galactic halo.

We have detected gamma-ray emission at the 6 σ level at energies greater than 500 GeV from the supernova remnant RX J0852.0−4622 (G266.2−1.2) using the

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We have achieved label free DNA hybridization detection at the level of a few femto-moles using on-chip terahertz (THz) integrated devices. The devices consist of two photoconductive switches for the generation and detection of THz pulses. A DNA specimen placed in a reservoir on the micro strip line (MSL) connecting the switches delays the propagating THz pulses. Different delay times were observed depending on the DNA conformation. The high sensitivity achieved is due to MSL design adjustment and the use of a specimen reservoir. Both simulations and experimental results indicate that devices with a narrower MSL have higher sensitivity.

SS433, located at the center of the supernova remnant W50, is a close proximity binary system consisting of a compact star and a normal star. Jets of material are directed outwards from the vicinity of the compact star symmetrically to the east and west. Non-thermal hard X-ray emission is detected from lobes lying on both sides. Shock accelerated electrons are expected to generate sub-TeV gamma rays through the inverse-Compton process in the lobes. Observations of the western X-ray lobe region of SS433/W50 system have been performed to detect sub-TeV gamma-rays using the 10m CANGAROO-II telescope in August and September, 2001, and July and September, 2002. The total observation times are 85.2 hours for ON source, and 80.8 hours for OFF source data. No significant excess of sub-TeV gamma rays has been found at 3 regions of the western X-ray lobe of SS433/W50 system. We have derived 99% confidence level upper limits to the fluxes of gamma rays and have set constraints on the strengths of the magnetic fields assuming the synchrotron/inverse-Compton model for the wide energy range of photon spectrum from radio to TeV. The derived lower limits are 4.3 microgauss for the center of the brightest X-ray emission region and 6.3 microgauss for the far end from SS433 in the western X-ray lobe. In addition, we suggest that the spot-like X-ray emission may provide a major contribution to the hardest X-ray spectrum in the lobe.Comment: 7 pages, 8 figures, to be published in Astroparticle Physic