Design of a CZT Gamma-Camera for GRB and Fast Transient Follow-up: a Wide-Field-Monitor for the EDGE Mission

The success of the SWIFT/BAT and INTEGRAL missions has definitely opened a new window for follow-up and deep study of the transient gamma-ray sky. This now appears as the access key to important progresses in the area of cosmological research and deep understanding of the physics of compact objects. To detect in near real-time explosive events like Gamma-Ray bursts, thermonuclear flashes from Neutron Stars and other types of X-ray outbursts we have developed a concept for a wide-field gamma-ray coded mask instrument working in the range 8-200 keV, having a sensitivity of 0.4 ph cm-2 s-1 in 1s (15-150 keV) and arcmin location accuracy over a sky region as wide as 3sr. This scientific requirement can be achieved by means of two large area, high spatial resolution CZT detection planes made of arrays of relatively large (~1cm2) crystals, which are in turn read out as matrices of smaller pixels. To achieve such a wide Field-Of-View the two units can be placed at the sides of a S/C platform serving a payload with a complex of powerful X-ray instruments, as designed for the EDGE mission. The two units will be equipped with powerful signal read out system and data handling electronics, providing accurate on-board reconstruction of the source positions for fast, autonomous target acquisition by the X-ray telescopes.Comment: 9 pages, 7 figures, SPIE Conference on UV, X-ray, and Gamma-Ray Instrumentation for Astronomy, San Diego 26-30 August 200

Compton Large Area Silicon Timing Tracker for Cosmic Vision M3

International audienceProposed in response to the ESA call for the third Medium size mission (M3), CAPSiTT is a small mission designed for a 3-year survey of the non-thermal high energy sky from an equatorial LEO orbit. With a large effective area and a very wide field of view, its single instrument, a silicon tracker, provides good imaging, spectroscopic and polarimetric capabilities with a sensitivity 10-100 times better than COMPTEL. Nucleosynthesis and particle acceleration mechanisms in various sites are the main scientific topics addressed by CAPSiTT

The UFFO (Ultra Fast Flash Observatory) Pathfinder: Science and Mission

Hundreds of gamma-ray burst (GRB) optical light curves have been measured since the discovery of optical afterglows. However, even after nearly 7 years of operation of the Swift Observatory, only a handful of measurements have been made soon (within a minute) after the gamma ray signal. This lack of early observations fails to address burst physics at short time scales associated with prompt emissions and progenitors. Because of this lack of sub-minute data, the characteristics of the rise phase of optical light curve of short-hard type GRB and rapid-rising GRB, which may account for ~30% of all GRB, remain practically unknown. We have developed methods for reaching sub-minute and sub-second timescales in a small spacecraft observatory. Rather than slewing the entire spacecraft to aim the optical instrument at the GRB position, we use rapidly moving mirror to redirect our optical beam. As a first step, we employ motorized slewing mirror telescope (SMT), which can point to the event within 1s, in the UFFO Pathfinder GRB Telescope onboard the Lomonosov satellite to be launched in Nov. 2011. UFFO's sub-minute measurements of the optical emission of dozens of GRB each year will result in a more rigorous test of current internal shock models, probe the extremes of bulk Lorentz factors, provide the first early and detailed measurements of fast-rise GRB optical light curves, and help verify the prospect of GRB as a new standard candle. We will describe the science and the mission of the current UFFO Pathfinder project, and our plan of a full-scale UFFO-100 as the next step.Comment: 4 pages, 5 figures, to appear in the 32nd International Conference on Cosmic Rays (ICRC), Beijing, August 11-18, 201

Efficacy of tissue brushing as measured by the prosthodontic tissue index

This study was conducted to determine the efficacy of brushing the oral mucosa supporting complete dentures with a soft brush to see if this treatment would reduce inflammation. The oral mucosa health status of 60 patients was monitored for 120 days using the PTI to measure inflammation. For comparison the patients were divided into two groups, and every effort was made to balance the groups for those variables that may effect inflammation. The patients were also compared with themselves. The experiment consisted of three phases; Phase 1 established baseline data, and Phases 2 and 3 were information-gathering sessions. Each patient received brushing instructions at the start of the brushing test period and additional brushing instruction during a reinforcement session after 30 days. Tissue brushing did reduce the inflammation index of the oral mucosa examined.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/74782/1/j.1754-4505.1984.tb00150.x.pd