Future directions for beam-foil spectroscopy

The beam-foil source has proved to be so useful for the study of atomic energy levels that it is almost trivial to propose a variety of new experiments involving new elements, higher energies, a broader wavelength range, shorter time intervals, pulsed beams, different targets, and new configurations in geometry or external fields. However, what is perhaps not so trivial is to propose experiments for which there is a specific purpose, experiments from which a novel kind of information might be expected. It is from this latter point of view that the author shall talk about experiments which seem to offer unusual opportunities to learn new things about atoms

Bloch oscillations in one-dimensional spinor gas

A force applied to a spin-flipped particle in a one-dimensional spinor gas may lead to Bloch oscillations of particle's position and velocity. The existence of Bloch oscillations crucially depends on the viscous friction force exerted by the rest of the gas on the spin excitation. We evaluate the friction in terms of the quantum fluid parameters. In particular, we show that the friction is absent for integrable cases, such as SU(2) symmetric gas of bosons or fermions. For small deviations from the exact integrability the friction is very weak, opening the possibility to observe Bloch oscillations.Comment: 4 pages, 2 figure

Cumulative identical spin rotation effects in collisionless trapped atomic gases

We discuss the strong spin segregation in a dilute trapped Fermi gas recently observed by Du et al. with "anomalous" large time scale and amplitude. In a collisionless regime, the atoms oscillate rapidly in the trap and average the inhomogeneous external field in an energy dependent way, which controls their transverse spin precession frequency. During interactions between atoms with different spin directions, the identical spin rotation effect (ISRE) transfers atoms to the up or down spin state, depending on their motional energy. Since low energy atoms are closer to the center of the trap than high energy atoms, the final outcome is a strong correlation between spins and positions.Comment: 4 pages, 2 figures; v2: comparison to experimental data adde

Charge of ions emitting spectral lines

Ion charge determination from emitting spectral lines using beam foil light source techniqu

Stark Broadening of several Ar I Spectral Lines in the Visible Part of the Spectrum

In order to complete data on Stark broadening parameters for Ar I line in the visible spectrum, we determined Stark widths and shifts due to electron, proton, and ionized helium impacts, for nine lines (4191.0, 4259.4, 5912.1, 6043.2, 6045.0, 6752.9, 7503.9, 7514.6, 7724.2 {\AA}), using jK coupling and semiclassical-perturbation theory. The obtained results will enter the STARK-B database, which is a part of Virtual Atomic and Molecular Data Center

Charge identification for spectral lines in nitrogen

Ion charge identification for spectral lines in nitrogen by beam foil light source techniqu

Stark effect in He 2 and H

Stark effect in helium isotopes and hydroge

Optical excitation of nonlinear spin waves

We demonstrate a technique for exciting spin waves in an ultracold gas of Rb-87 atoms based on tunable AC Stark potentials. This technique allows us to excite normal modes of spin waves with arbitrary amplitudes in the trapped gas, including dipole, quadrupole, octupole, and hexadecapole modes. These modes exhibit strong nonlinearities, which manifest as amplitude dependence of the excitation frequencies and departure from sinusoidal behavior. Our results are in good agreement with a full treatment of a quantum Boltzmann transport equation.Comment: 11 pages, 5 figure

Beam-foil spectrum of nitrogen at ultraviolet wavelengths

Spectrum analysis on foil excited nitrogen beam during acceleration at ultraviolet wavelength

The mean lives of some excited levels in nitrogen 1

Beam foil measurements of multiplet mean lives in nitrogen deca