Transferred orbital angular momentum in the low-energy electron impact excitation of the1S0-1P1transition in barium

Atomic collision parameters have been derived for electron impact excitation of calcium using the superelastic scattering method,at incident energies equivalent to 20, 25 and 35 eV. The pseudo-Stokes parameters for the superelastic process were determined, and the parameters P + lin , L + ⊥ , γ + and P + tot derived for the 4 1 P 1 state. The results are compared to a relativistic distorted-wave approximation (RDWA) theory, and to previous experimental results. At the highest incident energy the results presented here compare well with theory, but at the lowest energy, significant disagreement between theory and experiment is observed.

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Low energy superelastic scattering from the 4¹P₁state of calcium in an (e, 2e) spectrometer

Murray¹,

Cvejanović

2003

“…The experimental apparatus is a crossed-beam system where atomic targets are prepared in excited states by resonant laser pumping. The design has been introduced in previous work [3,4,9,16,17], and is described in detail in [33]. Figure 2 shows a schematic view of the experimental apparatus.…”

Section: Experimental Apparatusmentioning

confidence: 99%

Differential cross sections and electron impact coherence parameters for elastic electron scattering from laser-excited¹³⁸Ba

Hein¹,

Zetner²,

Bostock³

et al. 2012

Self Cite

We have measured and calculated differential cross sections and the P 3 collision Stokes parameter for elastic electron scattering from the laser-excited (. . . 6s6p 1 P 1 ) and cascade-populated (. . . 6s5d 3 D 1,2 ) levels of barium at 5, 10, and 20 eV impact energy. Measurements were performed using a crossed-beam apparatus, where excited-state atomic targets were prepared with resonant laser radiation incident on the electron-atom interaction region. Calculations were performed in the convergent close-coupling (CCC), relativistic CCC, and optical-model potential approximations. We present measured and calculated partial differential cross sections, which relate to differential cross sections and electron impact coherence parameters through the target state anisotropy introduced by the laser geometry.

“…The experimental apparatus is a crossed-beam system where atomic targets are prepared in excited states by resonant laser pumping. The overall design has been introduced in previous work [2,[13][14][15][16][17], and is described in detail in [11].…”

Section: Experimental Apparatusmentioning

confidence: 99%

Differential cross sections for electron-impact excitation of laser-excited¹⁷⁴Yb (…6s6p ³P₁)

Hein¹,

Kidwai²,

Zetner³

et al. 2010

Self Cite

We have measured and calculated electron-impact excitation cross sections from the laser-excited Yb (. . . 6s6p 3 P 1 ) level to the higher-lying Yb (. . . 6s6p 1 P 1 ), (. . . 6s5d 3 D 1,2,3 ) and (. . . 6s7s 3 S 1 ) levels at 20 eV impact energy. Measurements were performed using a crossed-beam apparatus, with resonant laser radiation incident on the electron-atom interaction region, providing excited-state atomic targets. Calculations were performed in the relativistic convergent close-coupling (RCCC), convergent close-coupling (CCC), and relativistic distorted-wave (RDW) approximations. We present measured and calculated partial differential cross sections (PDCS), which relate to differential cross sections and electron-impact coherence parameters through the target state anisotropy introduced by the laser geometry. Using theoretical predictions of the h electron-impact coherence parameter, we present the differential cross section for the 3 P 1 -3 S 1 excitation.