Searcharxiv⌕ Search

arXiv · physics/0609072

Photorecombination of berylliumlike Ti18+: Hyperfine quenching of dielectronic resonances

Abstract

The photorecombination spectrum of 48Ti18+ was measured employing the merged electron-ion beams technique at a heavy-ion storage ring. The experimental electron-ion collision energy range 0-80 eV comprises all dielectronic recombination (DR) resonances associated with 2s->2p (Delta N =0) core excitations as well as trielectronic recombination (TR) resonances that involve 2s2->2p2 core double-excitations. At low collision energies DR resonances are observed that are associated with the excitation of metastable 2s2p 3P0 primary ions with nearly infinite lifetime for the isotope 48Ti with zero nuclear spin. For the isotope 47Ti with nonzero nuclear spin hyperfine quenching of these resonances occurs. The procedure for obtaining the associated time constant from a recombination measurement is outlined.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

S. Schippers, E. W. Schmidt, D. Bernhardt, D. Yu, A. Mueller, M. Lestinsky, D. A. Orlov, M. Grieser, R. Repnow, A. Wolf. 2006-09-08. Photorecombination of berylliumlike Ti18+: Hyperfine quenching of dielectronic resonances. https://doi.org/10.1088/1742-6596%2F58%2F1%2F025

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

Isotopic effect on collisional widths and shifts of Hg clock transition induced by cold Rb atoms

We study the isotopic dependence of collisional widths and shifts of the Hg clock transition $^1$S$_0$-$^3$P$_0$ perturbed by the Rb atoms in the temperature range from 1 nK to 1 K. For this purpose, we model the Born-Oppenheimer effective interaction potential by including the leading long-range van der Waals coefficients. For elastic collisions, we show the connection between the dependence of collision line shape parameters on the reduced mass of colliding partners as well as the variation of the scattering length in the excited and ground states of the Hg-Rb system in the $\upmu$K temperature range. We confront the full quantum scattering calculations with a semi-classical approximation for collisional widths and shifts. We show that the shape resonances in excited and ground scattering states lead to significant variations of collisional line shape parameters with the change of the reduced mass of colliding atoms. We also indicate the possible influence of inelastic collisions, which could lead to universal behavior and significantly affect the dependence of collisional broadening and shifting on the isotopic combination of colliding atoms.

physics.atom-ph↗

Long-Baseline Phase-Coherent Microwave Reception Using Rydberg Atoms

A long baseline phase-coherent microwave receiver is demonstrated using a remotely interrogated cesium Rydberg atom sensor over an 8 m free-space optical link. A 3.989 GHz local oscillator (LO) is intensity-modulated onto an 852 nm optical probe and recovered remotely for atomic superheterodyne detection. A 509 nm coupling laser establishes a Rydberg electromagnetically induced transparency (EIT) system addressing the 6S1/2 to 6P3/2 to 56D5/2 ladder, with microwave coupling to 57P3/2. A test signal offset by 5 kHz generates an optically detected intermediate-frequency (IF) response returned to the reference station for centralized coherent acquisition. This eliminates independent remote oscillators, electronic IF acquisition, and distributed clock synchronization. Over 10 min, the differential phase between remote and local reference exhibits a standard deviation of 0.476 deg and a minimum overlapping phase Allan deviation of 0.048 deg at approximately 200 s averaging. Following optical-link interruption, the differential phase recovers without recalibration, with a measured pre- and post-interruption difference of 0.01 deg. These results demonstrate phase coherent remotely interrogated atomic microwave reception with reduced instrumentation, supporting future distributed interferometry, multistatic radar, and coherent sensor arrays.

physics.atom-ph↗

Simultaneous SI-traceable measurement of the amplitude and the ellipticity of microwave fields with cold Rydberg atoms

We present a method for the simultaneous measurement of the amplitude and the ellipticity of microwave fields using trap-loss spectroscopy based on Rydberg excitation of a cold ensemble of 87Rb atoms. The measurement consists of probing the energy spectrum of the $61S_{1/2}$ to $61P_{1/2}$ transition in the presence of microwave, which depends on the electric field amplitude $|E|$ and the third Stokes parameter $|S_3|$. We use a millimeter-size magneto-optical trap to perform strongly-localized measurements, which mitigates the effect of microwave field inhomogeneities. This allows us to work with large Rabi frequencies and thus resolve small deviations from linear or circular states of polarization. Taking into account the effect of non-resonant couplings to neighboring Rydberg states, we measure $|E|$ and $|S_3|$ with an accuracy on the order of 1 percent in the Autler-Townes regime where the measurements can be traced to the international system of units. By studying the visibility of the spectral features as a function of the polarization of the excitation laser beams, we extract some information on the angle of arrival of the microwave field onto the atoms, with good agreement between theory and experiment.

physics.atom-ph↗