121592881
Thermal problems on high flux beam lines
Abstract Wiggler and undulator magnets can provide very intense photon flux densities to beam line components. This paper addresses some thermal/materials consequences due to such impingement. The LBL/Exxon/SSRL hybrid-wiggler beam line VI [1] now nearing operation will be able to provide up to ∼ 7 kW of total photon power at planned SPEAR operating conditions. The first masks are located at 6.5 m from the source and may receive a peak power density (transverse to the beam) exceeding 20 kW/cm2. Significantly, this heat transfer rate exceeds that radiated from the sun's surface (7 kW/cm2) and is comparable to that if welding torches. Clearly, cooling and configuration are of critical importance. Configurations for the first mask, the movable mask and the pivot mask on this beam line are presented together with considerations of thermal stress fatigue and of heat transfer by conduction to water-cooling circuits. Some preliminary information on the heating of crystals and mirrors is also presented. For the future, many additional intense wiggler/undulator beam lines are contemplated at several storage rings. The design of these beamlines would be enhanced by faster and more accurate computational techniques. LBL is developing a computer code which will be capable of giving photon power densities onto impinged surfaces for a wide range of source and beam line parameters. These include electron beam energy, current, emittance and orbit deviations; wiggler/undulator length, period and magnetic field; photon energy and angular distribution; reflection/absorption at intermediate impinged surfaces; defining apertures and focusing by mirrors. Three-dimensional computer programs for temperature, stress and strain have been available for some years, but “user friendly” versions are being sought. Other items to pursue are also suggested.
116155554
Use of intense sub-microsecond electron bursts to produce rock shattering
116274825
EDDY CURRENTS, LANDAU-DAMPING COEFFICIENTS, AND THEIR IMPLICATIONS IN ELECTRON-RING COMPRESSOR DESIGN
119430569
Elliptical Vacuum Chamber Stress and Deflections
Equations are derived for the bending moments and stresses at all points and for deflections at the major and minor axes in a uniform-wall tubular chamber of elliptical cross section subjected to uniform pressure loading. Graphs are included to facilitate computations.
33708694
Acceleration of Uranium at the Bevalac
Recent upgrading projects have extended the mass range of particles that can be accelerated at the Bevalac to include any element of the periodic table to energies above 1 billion electron volts per atomic mass unit. This capability was verified on 11 May 1982 with the production of a uranium beam at 147.7 million electron volts per atomic mass unit.
115544101
Experimental superconducting accelerator ring (ESCAR)
Author(s): Avery, R.; Elioff, T.; Garren, A.; Gilbert, W.; Green, M.; Grander, H.; Hartwig, E.; Hopkins, D.; Lambertson, G.; Lofgren, E.; Lou, K.; Meuser, R.; Peters, R.; Smith, L.; Staples, J.; Thomas, R.; Wolgast, R.
119825872
Limits on heavy leptons with massive neutrinos