High energy

One approach being explored as a route to practical fusion energy uses heavy ion beams focused on an indirect drive target. Such beams will lose electrons while passing through background gas in the target chamber, and therefore it is necessary to assess the rate at which the charge state of the incident beam evolves on the way to the target. Accelerators designed primarily for nuclear physics or high energy physics experiments utilize ion sources that generate highly stripped ions in order to achieve high energies economically. As a result, accelerators capable of producing heavy ion beams of 10 to 40 MeV0amu with charge state 1 currently do not exist. Hence, the stripping cross sections used to model the performance of heavy ion fusion driver beams have, up to now, been based on theoretical calculations. We have investigated experimentally the stripping of 3.4 MeV0amu Kr ϩ7 and Xe ϩ11 in N 2 ; 10.2 MeV0amu Ar ϩ6 in He, N 2 , Ar, and Xe; 19 MeV0amu Ar ϩ8 in He, N 2 , Ar, and Xe; 30 MeV He ϩ1 in He, N 2 , Ar, and Xe; and 38 MeV0amu N ϩ6 in He, N 2 , Ar, and Xe. The results of these measurements are compared with the theoretical calculations to assess their applicability over a wide range of parameters.

HO Funsten · F. Allegrini · P. Bochsler · G. Dunn · S. Ellis · D. Everett · MJ Fagan · SA Fuselier · M. Granoff · M. Gruntman · AA Guthrie · J. Hanley · RW Harper · D. Heirtzler · P. Janzen · KH Kihara · B. King · H. Kucharek · MP Manzo · M. Maple · K. Mashburn · DJ McComas · E. ...

Racrufi es uno de los exponentes más reconocidos del arte fantástico mexicano. En este libro, los lectores encontrarán textos e imágenes de toda su trayectoria: dibujos infantiles, publicidades para las fiestas de high energy en México y obras personales ya de su trayectoria y evolución plásticas en la fantasía y la ciencia ficción. Él logra una integración única de referencias sobre historia de México, tecnología, robots, seres y objetos imaginarios que abren muchos caminos de interpretación.

Photoemission spectra taken at room temperature with high energy and angle resolution on Bi2Sr2CaCu2O8 single crystals reveal a band near EF with weak dispersion along lambdaX. It crosses EF at about 1/2 lambdaX and the occupied part becomes visible up to the Brillouin zone boundary in angle-resolved inverse photoemission spectra. Starting for T>Tc with a clear Fermi edge, for T<Tc

What aspects of optical fabrication technology need to be developed so as to facilitate existing planned missions, or enable new ones? Throughout the submillimeter to UV wavelengths, the common goal is to push technology to the limits to make the largest possible apertures that are diffraction limited. At any one wavelength, the accuracy of the surface must be better than lambda/30 (rms error). The wavelength range is huge, covering four orders of magnitude from 1 mm to 100 nm. At the longer wavelengths, diffraction limited surfaces can be shaped with relatively crude techniques. The challenge in their fabrication is to make as large as possible a reflector, given the weight and volume constraints of the launch vehicle. The limited cargo diameter of the shuttle has led in the past to emphasis on deployable or erectable concepts such as the Large Deployable Reflector (LDR), which was studied by NASA for a submillimeter astrophysics mission. Replication techniques that can be used to produce light, low-cost reflecting panels are of great interest for this class of mission. At shorter wavelengths, in the optical and ultraviolet, optical fabrication will tax to the limit the most refined polishing methods. Methods of mechanical and thermal stabilization of the substrate will be severely stressed. In the thermal infrared, the need for large aperture is tempered by the even stronger need to control the telescope's thermal emission by cooled or cryogenic operation. Thus, the SIRTF mirror at 1 meter is not large and does not require unusually high accuracy, but the fabrication process must produce a mirror that is the right shape at a temperature of 4 K. Future large cooled mirrors will present more severe problems, especially if they must also be accurate enough to work at optical wavelengths. At the very shortest wavelengths accessible to reflecting optics, in the x-ray domain, the very low count fluxes of high energy photons place a premium on the collecting area. It is not necessary to reach or even approach the diffraction limit, which would demand subnanometer fabrication and figure control. Replication techniques that produce large very lightweight surfaces are of interest for x-ray optics just as they are for the submillimeter region. Optical fabrication requirements are examined in more detail for missions in each of the three spectral regions of interest in astrophysics.

Applying the animated beam method the total cross sections (TCS) for double ionization (DI) of helium by electrons are measured in the collision energy region from threshold to 3 keV. The TCS for the same process are calculated at intermediate and high incident energies in the first Born approximation (FBA). The radial and angular correlations between the bound electrons and

The 8.9‐GeV/c Recycler antiproton storage ring is equipped with both stochastic and electron cooling systems. These cooling systems are designed to assist accumulation of antiprotons for the Tevatron collider operations. In this paper we report on an experimental demonstration of electron cooling of high‐energy antiprotons. At the time of writing this report, the Recycler electron cooling system is routinely used in collider operations. It has helped to set recent peak luminosity records. © 2006 American Institute of Physics