Search arXivSearch

arXiv · 1604.08449

Monte Carlo model for electron degradation in xenon gas

Abstract

We have developed a Monte Carlo model for studying the local degradation of electrons in the energy range 9-10000 eV in xenon gas. Analytically fitted form of electron impact cross sections for elastic and various inelastic processes are fed as input data to the model. Two dimensional numerical yield spectrum, which gives information on the number of energy loss events occurring in a particular energy interval, is obtained as output of the model. Numerical yield spectrum is fitted analytically, thus obtaining analytical yield spectrum. The analytical yield spectrum can be used to calculate electron fluxes, which can be further employed for the calculation of volume production rates. Using yield spectrum, mean energy per ion pair and efficiencies of inelastic processes are calculated. The value for mean energy per ion pair for Xe is 22 eV at 10 keV. Ionization dominates for incident energies greater than 50 eV and is found to have an efficiency of 65% at 10 keV. The efficiency for the excitation process is 30% at 10 keV.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Vrinda Mukundan, Anil Bhardwaj. 2016-03-12. Monte Carlo model for electron degradation in xenon gas. https://doi.org/10.1098/rspa.2015.0727

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

KEEP EXPLORING

Related papers

Vector Measurements Using Integrated Radio Frequency Atomic Magnetometers

We demonstrate reconstruction of three-dimensional radio-frequency (RF) magnetic-field vectors using a pair of integrated RF atomic magnetometers operated with orthogonal bias-field orientations. A theoretical and experimental analysis identifies a phase-ambiguity dead band that limits reconstruction when the two sensor responses become nearly identical. Measurements performed in an unshielded laboratory environment demonstrate accurate reconstruction of RF magnetic-field orientations and validate the predicted dependence of reconstruction accuracy on signal imbalance. These results establish integrated RF atomic magnetometers as a compact and sensitive platform for directional RF magnetic-field sensing, particularly at low frequencies, and provide a foundation for portable source-localization and field-mapping applications.

physics.atom-ph

Anomalously enhanced lifetimes of low angular momentum Rydberg states in singly charged alkaline-earth metal ions

Trapped ions excited to high-lying electronic states, so-called Rydberg states, open new opportunities for quantum simulation and quantum computing. Generally, the fidelity of quantum coherent operations critically depends on the longevity of Rydberg states. However, scaling laws predict that the lifetimes of Rydberg states in singly charged alkaline-earth metal ions are 16 times shorter, compared to their neutral atom counterparts. Here, we show that this is not generally the case. We report an anomalous lifetime enhancement of certain low angular momentum ionic Rydberg series by factors larger than eight. The anomaly is present at both zero and finite temperature, although it is caused by different mechanisms. At zero temperature, the anomalously enhanced lifetimes are caused by accidental cancellations of the relevant dipole transition matrix elements, while at room temperature the anomaly originates from the enlarged energetic separation of ionic Rydberg levels with respect to neutral-atom levels.

physics.atom-ph

Ytterbium lattice clock with systematic uncertainty of $1.3\times 10^{-18}$ and instability at the $10^{-19}$ level

We report an optical lattice clock based on $^{171}$Yb atoms with a total systematic uncertainty of $1.3\times 10^{-18}$. An in-vacuum buildup cavity was employed to enhance the lattice light power. Differential frequency measurement between two identical clocks facilitates the evaluation of systematic shifts. Synchronous comparison of the two clocks reached a stability level of $2.7\times 10^{-19}$ in an averaging time of 216,000~s. The blackbody radiation (BBR) shield which is placed in vacuum provides a well-characterized BBR environment, enabling an uncertainty contribution of $8.7\times 10^{-19}$ from the BBR Stark shift. Lattice light shifts were measured at different lattice depths $U$, and fitted with a fourth-order polynomial of $U$. The zero-linear-shift frequency $ν_{\mathrm{zero}}$ was determined to be 394 798 260.6(3) MHz. The lattice light shift can be controlled at an uncertainty level of $6.3\times 10^{-19}$ under typical operating conditions. Other systematic shifts have also been evaluated. The two clocks will be used for remote frequency comparisons between Shanghai and Wuhan.

physics.atom-ph