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171.
Th. Kuehl R. Bock S. Borneis E. Brambrink H. Brand J. Caird E. M. Campbell K. Cassou E. Gaul S. Goette C. Haefner T. Hahn H. M. Heuck D. H. H. Hoffmann D. Javarkova A. Klisnick H.-J. Kluge S. Kunzer T. Merz P. Neumayer P. Nickles M. D. Perry D. Reemts D. Ros M. Roth S. Samek W. Sandner G. Schaumann F. Schrader W. Seelig A. Tauschwitz R. Thiel D. Ursescu P. Wiewior U. Wittrock B. Zielbauer 《Hyperfine Interactions》2005,162(1-4):55-62
The high-energy high-power laser system PHELIX (Petawatt High Energy Laser for heavy Ion eXperiments) [1] is currently under construction at the Gesellschaft fuer Schwerionenforschung mbH (GSI) Darmstadt. With PHELIX GSI will
offer the unique combination of a high-current, high-energy (GeV/u) heavy-ion beam with an intense laser beam. This will open
the door to a variety of fundamental science issues in the field of atomic physics, plasma physics and nuclear physics. The
project will gain further interest in the near future by the dramatic increase of the accelerator performance with the starting
FAIR project at GSI [2]. This paper reports the current status of the project as well as the laser architecture. The proposed physics program and
a first experiment carried out with PHELIX, the realization of a transient collisionally excited x-ray laser [3], will also be reviewed briefly. 相似文献
172.
I. Mirebeau M. Hennion M.J.P. Gingras A. Keren K. Kojima M. Larkin G.M. Luke B. Nachumi W.D. Wu Y.J. Uemura I.A. Campbell G.D. Morris 《Hyperfine Interactions》1997,104(1-4):343-348
In the amorphous ( Fe1-x Mn_x)75 P16 B_6 Al_3 alloys, muon and neutron depolarization data, combined with the results of small angle neutron scattering, magnetization and Mössbauer spectroscopy, probe the existence of three distinct magnetic transitions at TC, TK and TF (TF < K < C). 相似文献
173.
Melting and solidification of pure gallium is studied using real-time radioscopy methods. Sharp contrast between melt and solid phases with a 3% density difference is illustrated. The interfacial shape reflects convective flow in the liquid phase. Comparisons are made between real-time non-intrusive X-ray observations and results gained from probing techniques and numerical simulations reported in the literature. Similar qualitative trends in temperature distribution, yet discrepancies in interfacial location and shape, are exhibited. 相似文献
174.
During the past five years, over 600 papers have been published on research work carried out with diacetylenes. Far fewer papers can be found on diacetylene mesophase studies, and these are reviewed in this paper. Some new findings by the authors are also presented. 相似文献
175.
It is well known that for a p-group, the invariant field ispurely transcendental (T. Miyata, Invariants of certain groupsI, Nagoya Math. J. 41 (1971), 69–73). In this note, weshow that a minimal generating set of this field can be chosenas homogeneous invariants from the invariant ring. As a result,we show that the invariant ring localized at one suitable invariantis the localization of a polynomial subring at this same invariant.This second result is a generalization of a recent result ofthe first author for cyclic groups of order p (H. E. A. Campbell,Rings of invariants of representations of Cp in characteristicp, preprint, 2006). As well, we specialize these results tothis latter case. 相似文献
176.
177.
57Fe Mössbauer measurements have been made on the ternary ThMn12-type intermetallic compounds Gd(Fe6–x
Cr
x
)Al6 withx=0, 0.5, 1.0, 1.5 and 2.0, at temperatures of 4.2 and 77 K. The principal effect of the Cr substitution is to reduce the57Fe magnetic hyperfine field at 4.2 K in this series. The analysis of the57Fe Mössbauer spectra is consistent with a ferromagnetic coupling between the Gd and Cr magnetic moments. These results are in agreement with previous studies by Felner et al. on GdCr6Al6, in which a ferromagnetic ordering withT
C=170 K was observed.On leave from Applied Acoustics Institute, Shaanxi Teachers University, Xian, PR China. 相似文献
178.
Davidson Sacha Bailey David Campbell Bruce A. 《Zeitschrift fur Physik C Particles and Fields》1994,61(4):613-643
We present model independent constraints on the masses and couplings to fermions ofB andL conserving leptoquarks. Such vector or scalar particles could have masses below 100 GeV and be produced at HERA; we list the generation dependent bounds that can be calculated from rare lepton and meson decays, meson-anti-meson mixing and various electroweak tests. 相似文献
179.
We calculate the cross section for hadroproduction of a pair of heavy quarks in a (3)S(1) color-singlet state at next-to-leading order in QCD. This corresponds to the leading contribution in the nonrelativistic QCD expansion for J/psi and Upsilon production. The higher-order corrections have a large impact on the p(T) distributions, enhancing the production at high p(T) at both the Fermilab Tevatron and the CERN Large Hadron Collider. The total decay rate of a (3)S(1) into hadrons at next-to-leading order is also computed, confirming for the first time the result obtained by Mackenzie and Lepage in 1981. 相似文献
180.
Adare A Adler SS Afanasiev S Aidala C Ajitanand NN Akiba Y Al-Bataineh H Alexander J Al-Jamel A Aoki K Aphecetche L Armendariz R Aronson SH Asai J Atomssa ET Averbeck R Awes TC Azmoun B Babintsev V Baksay G Baksay L Baldisseri A Barish KN Barnes PD Bassalleck B Bathe S Batsouli S Baublis V Bauer F Bazilevsky A Belikov S Bennett R Berdnikov Y Bickley AA Bjorndal MT Boissevain JG Borel H Boyle K Brooks ML Brown DS Bruner N Bucher D Buesching H Bumazhnov V Bunce G Burward-Hoy JM Butsyk S Camard X 《Physical review letters》2007,98(23):232302
We present azimuthal angle correlations of intermediate transverse momentum (1-4 GeV/c) hadrons from dijets in Cu+Cu and Au+Au collisions at square root sNN=62.4 and 200 GeV. The away-side dijet induced azimuthal correlation is broadened, non-Gaussian, and peaked away from Delta phi=pi in central and semicentral collisions in all the systems. The broadening and peak location are found to depend upon the number of participants in the collision, but not on the collision energy or beam nuclei. These results are consistent with sound or shock wave models, but pose challenges to Cherenkov gluon radiation models. 相似文献