Search results for "Elastic collision"
showing 10 items of 18 documents
Formation of dislocations and hardening of LiF under high-dose irradiation with 5–21 MeV 12C ions
2017
R. Zabels, I. Manika, J. Maniks, and R.Grants acknowledge the national project IMIS2, and A. Dauletbekova, M. Baizhumanov, and M. Zdorovets the Ministry of Education and Science of the Republic of Kazakhstan for the financial support.
Optical Shielding of Destructive Chemical Reactions between Ultracold Ground-State NaRb Molecules
2020
Polar quantum gases represent promising platforms for studying many-body physics and strongly correlated systems with possible applications e.g. in quantum simulation or quantum computation. Due to their large permanent electric dipole moment polar molecules in electric field exhibit strong long-range anisotropic dipole-dipole interactions (DDIs). The creation and trapping of ultracold dipolar diatomic molecules of various species are feasible in many experimental groups nowadays. However long time trapping is still a challenge even in the case of the so called nonreactive molecules which are supposed to be immune against inelastic collisions in their absolute ground state [1] . Various hyp…
Polarization detection of trapped electrons via interaction with polarized atoms
1971
Electrons were trapped in an electrostatic quadrupole trap with superimposed homogeneous magnetic field. The electrons were polarized by spin exchange with a polarized atomic beam. The free trapped electron polarization was converted to a change in the electron translational energy via spin-dependent inelastic collisions with the atomic beam, and the electron translational temperature was monitored. Discussed are the development of this variation of the measurement technique, characteristics of electron storage, and the electron-polarized atom inelastic interaction as a function of electron temperature and time. The method has been applied to the detection of the (g-2) resonance of free, st…
Collisional Broadening of Rotational Lines in the Stimulated Raman Pentad Q-Branch of CD4
1992
Self- and argon-broadening coefficients are reported for a number of Raman Q-branch transitions in the nu(1) and nu(2) + nu(4) bands of (C-12)D4 at room temperature (296 K). The coefficients display a variation with j and with C exp n (symmetry species A, E, F) that is essentially independent of collision partner and which is similar to the j- and C exp n-dependence found in previous measurements of the IR line-broadening coefficients. The rotationally inelastic collision rates previously measured by Foy et al. (1988) for (C-13)D4 (V4 = 0, 1) in collision with (C-13)D4 or Ar account for only a part of the Raman broadening rate, suggesting possibly significant contributions to the linewidths…
Vibrational relaxation of Na2 molecules in a triplet state: collisional transfer from a mixed A 1Σu+ − b3Πu gateway level to long-lived levels of b 3…
1997
Abstract Collision-induced vibrational transitions of Na2 within the b 3Π1u state have been observed in a free jet expansion, using two CW dye lasers for the pump and probe steps. The b-state is entered by the pump laser using a low mixed ( A 1 Σ u + − b 3 Π u ) level as a gateway. The occupations of various v′,J′-levels are studied as functions of the position in the flowing gas. The radiative lifetimes of Na2 in levels which had been populated by vibrational relaxation are found to be very long (> 4 μs). Cross-sections are estimated for vibrationally inelastic collisions with Na and Ar atoms.
A weakly-interacting many-body system of Rydberg polaritons based on electromagnetically induced transparency
2020
We proposed utilizing a medium with a high optical depth (OD) and a Rydberg state of low principal quantum number, $n$, to create a weakly-interacting many-body system of Rydberg polaritons, based on the effect of electromagnetically induced transparency (EIT). We experimentally verified the mean field approach to weakly-interacting Rydberg polaritons, and observed the phase shift and attenuation induced by the dipole-dipole interaction (DDI). The DDI-induced phase shift or attenuation can be viewed as a consequence of the elastic or inelastic collisions among the Rydberg polaritons. Using a weakly-interacting system, we further observed that a larger DDI strength caused a width of the mome…
Population of neutron-rich nuclei around 48ca with deep inelastic collisions
2009
The deep inelastic reaction 48Ca+64Ni at 6 MeV/A has been studied using the CLARA–PRISMA setup. Angular distributions for pure elastic scattering and total cross-sections of the most relevant transfer channels have been measured. The experimental results are compared with predictions from a semiclassical model, showing good agreement for the presently analyzed few neutrons transfer channels. The decay of the most intense reaction products has also been studied, giving indications of the population of states with very short lifetimes. Gadea Raga, Andrés, Gadea.Andres@ific.uv.es
Positrons and Electrons Emitted in Elastic and Dissipative Heavy Ion Collisions
1987
The main research line of the Tori group is the study of the reaction dynamics of dissipative collisions between heavy ions ia positron and electron spectroscopy. The last five years since the Lahnstein-Conference1 are marked for our group by the installation of a new experimental device for detecting positrons and electrons emitted in these collisions, the so-called Tori spectrometer2. The first part of this report is devoted therefore to describe the main characteristics of this apparatus.
Reaction dynamics and nuclear structure studies via deep inelastic collisions with heavy-ions: spin and parity assignment in49Ca
2011
The population and gamma decay of neutron rich nuclei around 48Ca has been measured at Legnaro National Laboratory with the PRISMA-CLARA setup, using deep-inelastic collisions (DIC) on 64Ni, at an energy approximately twice the Coulomb barrier. The reaction properties of the main products are investigated, focusing on total cross sections and angular distributions both integrated in energy and associated to the population of specific excited states. Gamma spectroscopy studies are also performed, giving evidence, for the first time in transfer reactions with heavy ions, of a large spin alignment (~70%), perpendicular to the reaction plane. This makes possible the use of angular distributions…
Rotational Transitions of CO+Induced by Atomic Hydrogen
2008
The CO+ molecular ion has been observed in photon-dominated regions. Recent modeling has not been able to explain the abundances of CO+ in these regions. The most abundant collision partners are believed to be hydrogen atoms, hydrogen molecules, and electrons. The reactions of these species with CO+ have been studied previously and found to be fast. The only inelastic processes studied before were collisions of CO+ with electrons. Here we investigate the inelastic collisions of CO+ with hydrogen atoms. We argue that this can be done on the lowest triplet electronic state. This implies that CO+ ions, in a hydrogen atom dominated surrounding, experiences a few inelastic collisions before reac…