排序方式: 共有33条查询结果,搜索用时 0 毫秒
1.
KM Varier AM Vinodkumar NVSV Prasad PV Madhusudhana Rao DL Sastry Lagy T Baby MC Radhakrishna NG Puttaswamy JJ Das P Sugathan N Madhavan AK Sinha DO Kataria 《Pramana》1999,53(3):529-533
Large enhancements have been observed in the sub-barrier fusion cross sections for Ti+Ni systems in our previous studies.
Coupled channel calculations incorporating couplings to 2+ and 3− states failed to explain these enhancements completely. A possibilty of transfer channels contributing to the residual enhancements
had been suggested. In order to investigate the role of relevant transfer channels, measurements of one- and two-nucleon transfer
were carried out for 46,48Ti+61Ni systems. The present paper gives the results of these studies. 相似文献
2.
Ter-Avetisyan S Schnürer M Busch S Risse E Nickles PV Sandner W 《Physical review letters》2004,93(15):155006
Deep dips in MeV ion spectra are obtained from water droplet targets irradiated by intense [(0.5-1.2) x 10(19) W/cm(2)] and ultrashort (35 fs) laser pulses. The existence of these dips is ascribed to the generation of a multielectron-temperature plasma, which is confirmed by our experiments. An existing fluid model based on hot-electron components with significantly different temperatures is consistent with the behavior we observe in the ion spectra of the femtosecond laser-driven interaction. The model provides a good simulation of the observed spectral dips and allows us to establish important parameters such as hot- and cold-electron temperatures and the respective electron density ratios. The result may be of interest for spectral tailoring of proton spectra in future applications of laser-generated proton beams. 相似文献
3.
E. Frster K. Goetz D. Zimmer P. Glas A. Goetsch R. Koch M. Naumann P. V. Nickles M. Schnürer I. Will 《Annalen der Physik》1987,499(1):61-73
This paper reports details on the design of the Nd: glass laser facility NIXE at the Central Institute of Optics and Spectroscopy, including the target chamber and the x-ray diagnostics, spatial and temporal behaviour of the 1.06 μm radiation generated are given. Plane, massive targets of aluminium and silicon have been irradiated with 6-nsec FWHM laser pulses. Investigations of laser produced Al- and Si-plasmas have been performed with spectral and spatial high resolution diagnostics, consisting of a 3 channel crystal-spectrometer, 2 crystal-microscopes, and 2 pinhole cameras and the results are presented. Line spectra have been interpreted within the hypothesis of a steady state coronal equilibrium. He-like lines of the Al-plasma indicate temperatures up to 400 eV and densities up to 2 · 1020 cm?3. Total x-ray photon flux in the He-like resonance line has been calculated giving 1013 phot/ster. 相似文献
4.
5.
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
6.
Janulewicz KA Schnürer M Tümmler J Priebe G Risse E Nickles PV Greenberg B Levin M Pukhov A Mandelbaum P Zigler A 《Optics letters》2005,30(12):1572-1574
Investigations of plasma produced by a boron nitride capillary discharge irradiated with a guided 20-TW Ti: sapphire laser pulse at a peak intensity of 4 x 10(18) W/cm2 are presented. The guided laser radiation in the plasma channel generated He-like ions that, subject to suitable plasma temperature, recombined into Li-like nitrogen ions. Intense radiation at a wavelength of 24.77 nm was observed, indicating possible lasing at the 3d(5/2) - 2p(3/2) transition in Li-like nitrogen. 相似文献
7.
Ion acceleration at the front and rear surfaces of thin foils with high-intensity 40-fs laser pulses
Ion acceleration from the front and rear sides of a foil target is observed by measurements of the ions’ spectral and spatial
emission characteristics when irradiating the targets with ultrashort (40-fs) high-intensity laser pulses. The experimental
results show that the origin of accelerated ions, from both the front and rear surfaces of the target, strongly depend on
the laser energy absorption mechanism. In particular, laser pulse parameters such as pulse duration and contrast are crucial
and determine the entire acceleration scenario. Thus, the experimental outcome can be controlled by selection of the irradiation
conditions.
The text was submitted by the authors in English. 相似文献
8.
9.
Optimum conditions for elliptical focusing are derived for singly resonant optical parametric oscillators with hemispherical resonator in dependence on double refraction. By elliptical focusing it is possible to focus more tightly in the non-walk-off plane. In a LiNbO3 oscillator pumped with 1,06 μm radiation the threshold pump power can be lowered about a factor 6 by elliptical focusing in comparison with circular focusing. 相似文献
10.
O. T. DeJesus L. G. Flores A. K. Converse R. M. Bartlett D. Murali R. Jeraj T. R. Oakes R. J. Nickles C. J. Jaskowiak 《Journal of Radioanalytical and Nuclear Chemistry》2006,269(3):561-564
Summary Exposure to several environmental chemicals in utero is associated with subtle deleterious effects in cognitive, motor and
behavioral functions. In order to assess in utero exposure to possible neurotoxins, fetal brain uptake of an exogenous compound
given to a pregnant rhesus macaque was investigated using PET/CT imaging. CT clearly delineated the fetus which allowed the
time course of the PET tracer in the fetal brain and other organs to be monitored. This study demonstrates the feasibility
of quantifying the absolute fetal uptake of chemicals given systemically to the mother. 相似文献