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With the coming launch of the Swift satellite, there will be many new opportunities to study the physics of the prompt optical emission from gamma ray bursts with robotic ground-based telescopes. We discuss a new imaging system under development at Los Alamos National Laboratory that will provide simultaneous multicolor photometry of the rapidly evolving prompt optical emission in the first minutes after a burst trigger. This next generation system employs state-of-the-art photon-counting imaging technology at the focal plane of a rapidly slewing telescope. The imaging sensor is composed of an S-20 photocathode, stacked microchannel plates, and crossed delay line readout electronics that together are capable of measuring the time of arrival and positions for individual optical photons with 200 picosecond time resolution. The imager is coupled with electronically tunable liquid-crystal filters to provide essentially simultaneous linear polarization and multicolor photometric measurements of the prompt optical emission from a gamma ray bursts. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

While it has been known for centuries that the optical sky is variable, monitoring the sky for optical transients with durations as short as a minute is an area of astronomical research that remains largely unexplored. Prompt follow-up observations of Gamma Ray Bursts have shown that bright, explosive, optical transients exist. However, there are many reasons to suspect the existence of explosive optical transients that cannot be located through sky monitoring by high-energy satellites. The RAPTOR sky monitoring system is an autonomous system of telescope arrays at Los Alamos National Laboratory that identifies fast optical transients as short as a minute and makes follow-up observations in real time. The core of the RAPTOR system is composed of two arrays of telescopes, separated by 38 kilometers, that stereoscopically monitor a field of about 1300 square degrees for transients down to about 12.5th magnitude in 30 seconds. Both arrays are coupled to real-time data analysis pipelines that are designed to identify transients on timescales of seconds. Each telescope array also contains a more sensitive higher resolution “fovea” telescope, capable of both measuring the light curve at a faster cadence and providing color information. In a manner analogous to human vision, each array is mounted on a rapidly slewing mount so that the “fovea” of the array can be rapidly directed for real-time follow-up observations of any interesting transient identified by the wide-field system. We discuss the first results from RAPTOR and show that stereoscopic imaging and the absence of measurable parallax is a powerful tool for distinguishing real celestial transients in the “forest” of false positives. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

The ALEPH experiment, in the year 2000 recorded an excess of Higgs signal-like events of ∼ 3σ over the background-only hypothesis, for a Higgs mass of ∼ 115 GeV. This note presents the first results after the final data taking, which were published in November 2000. [ABSTRACT FROM AUTHOR]