Search results for "Ground state"
showing 10 items of 928 documents
High-Resolution Jet-Cooled Spectroscopy of SF6: The ν2+ ν6Combination Band of32SF6and the ν3Band of the Rare Isotopomers
1998
The Fourier transform infrared spectrum of SF6 was recorded in a supersonic expansion jet of an SF6/argon mixture. The SF6:Ar seeding ratio was 2:3. The instrumental bandwidth was 0.005 cm-1. A globar source and an MCT detector were used. A rotational temperature of approximately 30 K was achieved. The nu2 + nu6 combination band of 32SF6 was analyzed using a modified version of the spherical top data system (STDS) programs developed in Dijon. A very good fit was obtained for this band with an rms of 0.0036 cm-1. The effective Hamiltonian was developed up to fourth order for the nu2 + nu6 part, to second order for the nu2 and ground state parts, and to first order for the nu6 part. Five hund…
Singlet and triplet potentials of the ground-state atom pair Rb+Cs studied by Fourier-transform spectroscopy
2011
A comprehensive study of the $X {}^{1}\ensuremath{\Sigma}{}^{+}$ and $a {}^{3}\ensuremath{\Sigma}{}^{+}$ electronic states of the Rb and Cs atom pair in RbCs is presented. Abundant spectroscopic data for the $^{85}\mathrm{Rb}$$^{133}\mathrm{Cs}$ and $^{87}\mathrm{Rb}$$^{133}\mathrm{Cs}$ isotopologues were obtained from Fourier-transform spectra of laser-induced fluorescence (LIF) from the $B {}^{1}\ensuremath{\Pi}$ and $(4){}^{1}\ensuremath{\Sigma}{}^{+}$ states to the $a {}^{3}\ensuremath{\Sigma}{}^{+}$ (4549 transitions) and $X {}^{1}\ensuremath{\Sigma}{}^{+}$ (15 709 transitions) states. The $X {}^{1}\ensuremath{\Sigma}{}^{+}$ state data were complemented by about 15 500 transitions obta…
Light-induced polarization effects in atoms with partially resolved hyperfine structure and applications to absorption, fluorescence, and nonlinear m…
2009
The creation and detection of atomic polarization is examined theoretically, through the study of basic optical-pumping mechanisms and absorption and fluorescence measurements, and the dependence of these processes on the size of ground- and excited-state hyperfine splittings is determined. The consequences of this dependence are studied in more detail for the case of nonlinear magneto-optical rotation in the Faraday geometry (an effect requiring the creation and detection of rank-two polarization in the ground state) with alkali atoms. Analytic formulas for the optical rotation signal under various experimental conditions are presented.
Ground-state magneto-optical resonances in cesium vapor confined in an extremely thin cell
2007
Experimental and theoretical studies are presented related to the ground-state magneto-optical resonance prepared in Cesium vapour confined in an Extremely Thin Cell (ETC, with thickness equal to the wavelength of the irradiating light). It is shown that the utilization of the ETC allows one to examine the formation of a magneto-optical resonance on the individual hyperfine transitions, thus distinguishing processes resulting in dark (reduced absorption) or bright (enhanced absorption) resonance formation. We report on an experimental evidence of the bright magneto-optical resonance sign reversal in Cs atoms confined in the ETC. A theoretical model is proposed based on the optical Bloch equ…
Laser spectroscopy of the 1001nm ground state transition in dysprosium
2018
We present a direct excitation of the presumably ultranarrow $1001\ensuremath{-}\mathrm{nm}$ ground-state transition in atomic dysprosium. By using resonance ionization spectroscopy with pulsed Ti:sapphire lasers at a hot cavity laser ion source, we were able to measure the isotopic shifts in the $1001\ensuremath{-}\mathrm{nm}$ line between all seven stable isotopes. Furthermore, we determined the upper level energy from the atomic transition frequency of the $^{164}\mathrm{Dy}$ isotope as $9991.004(1)\phantom{\rule{0.16em}{0ex}}{\mathrm{cm}}^{\ensuremath{-}1}$ and confirm the level energy listed in the NIST database. Since a sufficiently narrow natural linewidth is an essential prerequisit…
Spin-multipole nuclear matrix elements in thepnquasiparticle random-phase approximation: Implications forβandββhalf-lives
2017
Half-lives for 148 potentially measurable 2nd-, 3rd-, 4th-, 5th-, 6th-, and 7th-forbidden unique beta transitions are predicted. To achieve this, the ratio of the nuclear matrix elements (NMEs), calculated by the proton-neutron quasiparticle random-phase approximation (pnQRPA), ${M}_{\mathrm{pnQRPA}}$, and a two-quasiparticle (two-qp) model, ${M}_{\mathrm{qp}}$, is studied and compared with earlier calculations for the allowed Gamow-Teller (GT) ${1}^{+}$ and first-forbidden spin-dipole (SD) ${2}^{\ensuremath{-}}$ transitions. The present calculations are done using realistic single-particle model spaces and $G$-matrix based microscopic two-body interactions. In terms of the ratio $k={M}_{\m…
Hyperfine interaction in the Autler-Townes effect: The formation of bright, dark, and chameleon states
2017
This paper is devoted to clarifying the implications of hyperfine (HF) interaction in the formation of adiabatic (i.e., ``laser-dressed'') states and their expression in the Autler-Townes (AT) spectra. We first use the Morris-Shore model [J. R. Morris and B. W. Shore, Phys. Rev. A 27, 906 (1983)] to illustrate how bright and dark states are formed in a simple reference system where closely spaced energy levels are coupled to a single state with a strong laser field with the respective Rabi frequency ${\mathrm{\ensuremath{\Omega}}}_{S}$. We then expand the simulations to realistic hyperfine level systems in Na atoms for a more general case when non-negligible HF interaction can be treated as…
Excited states inPd115populated in theβ−decay ofRh115
2010
Excited states in $^{115}\mathrm{Pd}$, populated following the ${\ensuremath{\beta}}^{\ensuremath{-}}$ decay of $^{115}\mathrm{Rh}$ have been studied by means of $\ensuremath{\gamma}$ spectroscopy after the Penning-trap station at the IGISOL facility, University of Jyv\"askyl\"a. The $1$$/$$2$${}^{+}$ spin and parity assignment of the ground state of $^{115}\mathrm{Pd}$, confirmed in this work, may indicate a transition to an oblate shape in Pd isotopes at high neutron number.
Comparison of electromagnetic and nuclear dissociation of Ne-17
2018
8 pags., 10 figs., 3 tabs.
Ground and Excited State First-Order Properties in Many-Body Expanded Full Configuration Interaction Theory
2020
The recently proposed many-body expanded full configuration interaction (MBE-FCI) method is extended to excited states and static first-order properties different from total, ground state correlation energies. Results are presented for excitation energies and (transition) dipole moments of two prototypical, heteronuclear diatomics---LiH and MgO---in augmented correlation consistent basis sets of up to quadruple-$\zeta$ quality. Given that MBE-FCI properties are evaluated without recourse to a sampled wave function and the storage of corresponding reduced density matrices, the memory overhead associated with the calculation of general first-order properties only scales with the dimension of …