Y. K. Kwon

Measurement of the drift mobilities and the mobility-lifetime products of charge carriers in a CdZnTe crystal by using a transient pulse technique

In this work we present results on the measurement of the drift mobility and the mobility-lifetime product of charge carriers in a 16-pixellated CdZnTe detector. For the determination of an interaction position based on the pulse rise-time method in a CZT detector, it is necessary to characterize the transport properties governed by drift mobility and lifetime for electrons and holes. In order to extract the transport properties of an electron and a hole, we bombarded 5.5-MeV alpha particles from a 241Am source and 81-keV gamma rays emitted from a 133Ba source on the negatively biased contact of the CZT detector. A time-of-flight (TOF) method was used to measure the electron drift mobility at room temperature whose value turned out to be 906.4 cm2/V⋅ s. With the Hechts equation, the electron mobility-lifetime product was also determined from the bias-dependent alpha response and was equal to (9.88 ± 2.33) × 10−3 cm2/V. On the other hand, the hole mobility-lifetime product was evaluated by a model based on the average charge collection efficiency which accounts for the absorption probability with a given photon energy. By using a single parameter fitting of the model, we obtained the hole mobility-lifetime product of (8.28 ± 0.17) × 10−4 cm2/V.

First direct measurement of the C 11 (α,p) N 14 stellar reaction by an extended thick-target method

The

Alpha resonant scattering for astrophysical reaction studies

^{11}

Astrophysical S-factor for destructive reactions of lithium-7 in big bang nucleosynthesis

C(

Nuclear clusters studied with alpha resonant scatterings using RI beams at CRIB

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α-resonance structure in11C studied via resonant scattering of7Be+αand with the7Be(α,p) reaction

, p) reaction is an important

Experimental challenge to nucleosynthesis in core-collapse supernovae - Very early epoch of type II SNe -

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Role of clusters in nuclear astrophysics with Cluster Nucleosynthesis Diagram (CND)

-induced reaction competing with

Alpha-cluster dominance in the αp process in explosive hydrogen burning

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Alpha-resonance structure in

-limited hydrogen-burning processes in high-temperature explosive stars. We directly measured its reaction cross sections both for the ground-state transition (