23 research outputs found
CEM2k and LAQGSM as Event Generators for Space-Radiation-Shielding and Cosmic-Ray-Propagation Applications
The CEM2k and LAQGSM codes have been recently developed at Los Alamos
National Laboratory to simulate nuclear reactions for a number of applications.
We have benchmarked our codes against most available measured data at incident
particle energies from 10 MeV to 800 GeV and have compared our results with
predictions of other current models used by the nuclear community. Here, we
present a brief description of our codes and show illustrative results to show
that CEM2k and LAQGSM can be used as reliable event generators for
space-radiation-shielding, cosmic-ray-propagation, and other astrophysical
applications. Finally, we show the use of our calculated cross sections
together with experimental data from our LANL T-16 compilation to produce
evaluated files which we use in the GALPROP model of galactic particle
propagation to better constrain the size of the CR halo.Comment: 10 pages, 9 figures, LaTeX, talk given at the World Space Congress
2002, 34th COSPAR Scientific Assembly, Houston, Texas, USA, 10-19 October
2002, to appear in Advances in Space Researc
Small-angle fragmentation of carbon ions at 0.6 GeV/n: a comparison with models of ion-ion interactions
Momentum distributions of hydrogen and helium isotopes from 12C fragmentation at 3.5° were measured at 0.6 GeV/nucleon in the FRAGM experiment at ITEP TWA heavy ion accelerator. The fragments were selected by correlated time of flight and dE/dx measurements with a magnetic spectrometer with scintillation counters. The main attention was drawn to the high momentum region where the fragment velocity exceeds the velocity of the projectile nucleus. The momentum spectra of fragments span the region of the fragmentation peak as well as the cumulative region. The differential cross sections cover six orders of magnitude. The distributions measured are compared to the predictions of three ion-ion interaction models: BC, QMD and LAQGSM03.03. The kinetic energy spectra of fragments in the projectile rest frame have an exponential shape with two temperatures, being defined by their slope parameters
Magnetohydrodynamic Oscillations in the Solar Corona and Earth’s Magnetosphere: Towards Consolidated Understanding
Усиление эффекта Гуса-Хенхен при отражении гауссова пучка от диэлектрической пластины
International audienc
Small-angle fragmentation of carbon ions at 0.6 GeV/n: a comparison with models of ion-ion interactions
Small-angle fragmentation of carbon ions at 0.6 GeV/n: a comparison with models of ion-ion interactions
Momentum distributions of hydrogen and helium isotopes from 12C fragmentation at 3.5° were measured at 0.6 GeV/nucleon in the FRAGM experiment at ITEP TWA heavy ion accelerator. The fragments were selected by correlated time of flight and dE/dx measurements with a magnetic spectrometer with scintillation counters. The main attention was drawn to the high momentum region where the fragment velocity exceeds the velocity of the projectile nucleus. The momentum spectra of fragments span the region of the fragmentation peak as well as the cumulative region. The differential cross sections cover six orders of magnitude. The distributions measured are compared to the predictions of three ion-ion interaction models: BC, QMD and LAQGSM03.03. The kinetic energy spectra of fragments in the projectile rest frame have an exponential shape with two temperatures, being defined by their slope parameters
Carbon fragmentation at 300 MeV/nucleon vs transport codes
Momentum spectra of all long-lived fragments from 12C fragmentation at 3.5° have been measured. Differential cross sections span up to five orders of its magnitude. The preliminary results are compared with predictions of two transport codes: INCL++ and LAQGSM03.03. Both models give a good description of the data except few items which are discussed
Light fragments from (C + Be) interactions at 0.6 GeV/nucleon
Nuclear fragments emitted at 3.5° in 12C fragmentation at 0.6 GeV/nucleon have been measured. The spectra obtained are used for testing the predictions of four ion-ion interaction models: INCL++, BC, LAQGSM03.03 and QMD as well as for the comparison with the analytical parametrization in the framework of thermodynamical picture of fragmentation
Entwicklung und Test einer Auswerteelektronik fuer optische Quadratursignale
Es wird eine hochaufloesende, schnelle Signalauslesung und -aufbereitung fuer phasenverschobene (optische) Signale, speziell Zweistrahlinterferometer, vorgestellt. Im Bereich von zwei Amplitudendekaden und von DC bis zu mehreren Megahertz werden digitale Pulse mit analogen Zwischensignalen erzeugt sowie die Phasenlage der Signale mit hoher Genauigkeit bestimmt. Der halbautomatische Abgleich der Elektronik erfolgt mit den ersten Messsignalen. (orig.)This paper describes a fast, high resolution, electronic processing and readout unit for phase-shifted optical signals, especially from two-beam interferometers. Over two decades of amplitude and from DC up to several Megahertz, it produces digital pulses and analog linearized signals between these pulses. The phase difference between the signals is also measured with high resolution. Half-automatic signal offset adjustment is done with the first signals received. (orig.)SIGLEAvailable from TIB Hannover: RN 278(92-11) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman
Carbon fragmentation at 300 MeV/nucleon vs transport codes
Momentum spectra of all long-lived fragments from 12C fragmentation at 3.5° have been measured. Differential cross sections span up to five orders of its magnitude. The preliminary results are compared with predictions of two transport codes: INCL++ and LAQGSM03.03. Both models give a good description of the data except few items which are discussed