Orbital alignment cross sections by stimulated emission probing : the state-to-state Ca Rydberg process Ca(4s17d^1D_2)+Xe->Ca(4s18p^1P_1)+Xe

The initial state alignment effect vs relative velocity is measured for a state-to-state Ca Rydberg collisional energy transfer process. The stimulated emission detection method is used to determine the alignment effect for the n,1-changing transition: Ca(4s17d1D2) + Xe -->Ca(4s18p1P1) + Xe+deltaE = -1.7cm-1. The rate of electronic energy transfer in this state-changing collision is observed to vary with the direction of the Rydberg electron charge cloud relative to the collision axis. Both the expected cos(4beta) and cos(2beta) dependencies are observed. The alignment data are analyzed to obtain the relative cross sections for the individual Ca(1D2) magnetic sublevels. The values of the m-sublevel cross sections sigma0 : sigma1 : sigma2 are 1.13+/-0.02:1.11+/-0.02:0.83+/-0.02. Qualitative interpretations of the relative cross sections in terms of both molecular (van der Waals) Born-Oppenheimer potentials and the impulse approximation are presented

Alignment probing of Rydberg states by stimulated emission

The possibility of probing the collisions of aligned Rydberg atoms by stimulated emission is assessed with studies of a polarized state and a new measurement of a collisional alignment effect in atomic Ca. The stimulated emission method uses a laser to dump the desired state to a lower level which subsequently fluoresces. The technique can be used to obtain populations and polarization dependent information. First, the method is tested by applying it to an aligned Ca(4s17d¿1D2) state. Alignment curves are measured when the initial state is prepared with both parallel and perpendicular relative polarizations. The experimentally observed alignment compares well with that derived from theoretical considerations of a saturated stimulated transition. Second, a two-vector collisional alignment experiment (initial state and relative velocity vector) is performed to study the energy transfer process Ca(4s7d¿1D2)+He¿Ca(4s6f¿1F3)+He+¿E=17.7 cm-1, and alignment effects are measured by both stimulated emission and conventional direct fluorescence detection. A preference for the ¿m¿=1 and 2 initial states is observed in the relative cross sections. Essentially identical data are obtained with the two detection methods when elliptically polarized light is used for the stimulated emission detection method. The stimulated emission technique can provide alignment and population information of the final states, making it an excellent new tool for both three-vector correlation experiments and state-to-state Rydberg transitions

Internalized and Anticipated Stigmatization in Patients with Gout

Objective: To investigate the relationship between stigma perception and demographic, clinical, and psychosocial variables. Methods: A sample of 50 patients with gout and prescribed urate-lowering medication (84% were males, mean serum urate 0.34 mmol/l) completed questionnaires on internalized and anticipated stigma, demographics, clinical gout-related variables, and psychosocial variables (illness perceptions, illness-related disability, illness-related body satisfaction, intentional nonadherence). Serum urate level was obtained from the most recent blood test. Results: In this sample, 26% experienced internalized stigma, 26% expected to be stigmatized by friends or family members, and 14% by health care workers. Univariate regression analyses showed that younger age, ethnicity other than New Zealand European, increased severity of gout pain, cognitive and emotional illness perceptions, greater illness-related disability, and increased intentional nonadherence to urate-lowering medication were associated with increased internalized and anticipated stigma. Younger age, emotional illness response, and intentional nonadherence were the only variables explaining incremental variance of the experience of anticipated stigma in a multivariate regression model. Conclusion: Internalized and anticipated illness-related stigma was reported by a subgroup of patients with gout. The experience of stigma is associated with younger age, a negative emotional illness response, and intentions to not adhere with a medical treatment

Orbital alignment cross sections by stimulated emission probing : the state-to-state Ca Rydberg process Ca(4s17d^1D_2)+Xe->Ca(4s18p^1P_1)+Xe

The initial state alignment effect vs relative velocity is measured for a state-to-state Ca Rydberg collisional energy transfer process. The stimulated emission detection method is used to determine the alignment effect for the n,1-changing transition: Ca(4s17d1D2) + Xe -->Ca(4s18p1P1) + Xe+deltaE = -1.7cm-1. The rate of electronic energy transfer in this state-changing collision is observed to vary with the direction of the Rydberg electron charge cloud relative to the collision axis. Both the expected cos(4beta) and cos(2beta) dependencies are observed. The alignment data are analyzed to obtain the relative cross sections for the individual Ca(1D2) magnetic sublevels. The values of the m-sublevel cross sections sigma0 : sigma1 : sigma2 are 1.13+/-0.02:1.11+/-0.02:0.83+/-0.02. Qualitative interpretations of the relative cross sections in terms of both molecular (van der Waals) Born-Oppenheimer potentials and the impulse approximation are presented

Alignment probing of Rydberg states by stimulated emission

The possibility of probing the collisions of aligned Rydberg atoms by stimulated emission is assessed with studies of a polarized state and a new measurement of a collisional alignment effect in atomic Ca. The stimulated emission method uses a laser to dump the desired state to a lower level which subsequently fluoresces. The technique can be used to obtain populations and polarization dependent information. First, the method is tested by applying it to an aligned Ca(4s17d¿1D2) state. Alignment curves are measured when the initial state is prepared with both parallel and perpendicular relative polarizations. The experimentally observed alignment compares well with that derived from theoretical considerations of a saturated stimulated transition. Second, a two-vector collisional alignment experiment (initial state and relative velocity vector) is performed to study the energy transfer process Ca(4s7d¿1D2)+He¿Ca(4s6f¿1F3)+He+¿E=17.7 cm-1, and alignment effects are measured by both stimulated emission and conventional direct fluorescence detection. A preference for the ¿m¿=1 and 2 initial states is observed in the relative cross sections. Essentially identical data are obtained with the two detection methods when elliptically polarized light is used for the stimulated emission detection method. The stimulated emission technique can provide alignment and population information of the final states, making it an excellent new tool for both three-vector correlation experiments and state-to-state Rydberg transitions

Infrared spectroscopic, x-ray, and nanoscale characterization of strontium titanate thin films

Attenuated total reflectance (ATR) measurements were performed using Fourier transform infrared (FTIR) spectroscopy in the ATR mode with a thallium iodobromide (KRS-5) crystal to measure the frequencies of the v{sub 3} and v{sub 4} phonon absorption bands in thin Sr titanate films deposited on single-crystal Y-Ba Cu oxide (YBCO), La aluminate, Mg oxide, and Sr titanate substrates. The KRS-5 crystal enabled FTIR-ATR measurements at frequencies above 400 cm{sup -1}. Atomic force microscopy (AFM) and x-ray diffraction (XRD) measurements were also made to further characterize the films. The measurements were repeated on single-crystal specimens of Sr titanate and the substrates for comparison. Softening in the frequency of the v{sub 4} transverse optical phonon in the lattice-mismatched films below the established value of 544 cm{sup -1} is indicative of the highly textured, polycrystalline ceramic nature of the films and is consistent with the XRD and AFM results