The analyzing power A in 28-GeV/c proton-proton elastic scattering was measured with a polarized proton target and a high-intensity unpolarized proton beam at the Brookhaven National Laboratory alternating-gradient synchrotron. ThePj^^ range of 2.85 to 5.95 (GeY/c)'^ was covered with good precision. A small dip of about -3.5% was found near Pj^^ =3.5 (GeV/c)^ where a 24-GeV/c CERN experiment had reported a deep dip of about -16% with large errors. In the previously unexplored large-P^^ region near 6 (GeV/c)^ these new large-error points suggest that^ may be rising.
Future Astrophysics missions operating in the hard X-ray/Soft Gamma ray range is slated to carry novel focusing telescopes based on the use of depth graded multilayer reflectors. Current design studies show that, at the foreseen focal lengths, it should be feasible to focus X-rays at energies as high as 300 keV. These designs use extrapolations of theoretical and experimentally determined optical constants from below 200 keV. In this paper we report on the first experimental determination of optical constants up to and above 200 keV. We present these first results as obtained at the National Synchrotron Light Source in Brookhaven and compare these to results obtained previously up to 180 keV of some of the same materials at the European Synchrotron Radiation Facility in Grenoble.
bOsservatorio Astronomico di Brera -23808 Merate(Lc) -Italy CNASA/Marshall Space Flight Center dUSRA, AL eUnjversjty of AL 1BCV Progetti, Milano Raytheon, ITSS, AL ABSTRACT The Constellation-X mission, planned for launch in 2013, will feature an array of hard-x-ray telescopes (HXT) with a total collecting area of greater than 1500 cm2 at 40 keY. Two technologies are currently being investigated for the optics of these telescopes including multilayer-coated Eletroformed-Nickel-Replicated (ENR) shells. The attraction of the ENR process is that the resulting full-shell optics are inherently stable and offer the prospect of better angular resolution which results in lower background and higher instrument sensitivity. The challenge for this process is to meet a relatively tight weight budget with a relatively dense material (pnjckel 9 g/cm3.)To demonstrate the viability of the ENR process we are fabricating a prototype HXT mirror module to be tested against a competing segmented-glass-shell optic. The ENR prototype will consist of 5 shells of diameters from 150 mm to 280 mm with a length of 426 mm. To meet the stringent weight budget for Con-X, the shells will range in thickness from 100 microns to 150 microns. The innermost of these will be coated with Iridium, while the remainder will be coated with graded-dspaced W/Si multilayers.Mandrels for these shells are in the fabrication stage, the first test shells have been produced and are currently undergoing tests for figure and microroughness. A tentative date of June '04 has been set for the prototype X-ray testing at MSFC. Issues currently being addressed are the control of stresses in the multiplayer coating and ways of mitigating their effects on the figure of the necessarily thin shells. The fabrication, handling and mounting of these shells must be accomplished without inducing permanent figure distortions.A full status report on the prototype optic will be presented along with test results as available.
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