Zhang Xue-Heng

The β Decay of 21N

The β-delayed neutron and γ energy spectra taken from the decay of neutron-rich nucleus 21N were measured by using the β–γ and β – n coincidence detection method. Thirteen new neutron groups ranging from 0.28MeV to 4.98MeV and with a total branching ratio of 88.7 ± 4.2% were observed and presented. One γ transition with an energy of 1222keV emitted from the excited state of 21O, and four γ transitions with energies of 1674, 2397, 2780, and 3175keV emitted from the excited states of 20O were identified in the β decay chain of 21N. The β decay half-life for 21N is determined to be 82.9 ± 1.9 ms. The uncertainty of half-life is much smaller than the previous result.

Towards the full realization of the RIBLL2 beam line at the HIRFL-CSR complex

The RIBLL2 in-flight separator at IMP, the secondary beam line between two storage rings at the \blue{\uwave{Heavy Ion Research Facility in Lanzhou (HIRFL-CSR)}}, has been commissioned to study the rare-isotope beam (RIB) physics at around 300 MeV/nucleon for the first time, in combination of the external target facility (ETF). The unambiguous particle identification in mass and charge states for

Knockout reaction induced by 6He at 61.2 MeV/u

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Quasi-Elastic Scattering of 16C from 12C at 47.5 MeV/Nucleon

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Study of Borromean halo nuclei by the neutron wall with simulation

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A time-of-flight system for the external target facility

Ar fragments has been achieved in recent experiments. A full realization of RIBLL2 will open many potentials to address important RIB physics problems at around 300 MeV/nucleon.

A TOF-PET prototype with position sensitive PMT readout

A knockout reaction induced by 6He at 61.2 MeV/u was carried out at the HIRFL-RIBLL radioactive beam line. The α core fragments at forward angles were detected in coincidence with the recoiled protons at large angles. From this coincident measurement the valence nucleon knockout mechanism and the core knockout mechanism can be separated according to the polar angle correlation between the core fragments and the recoiled protons. It is demonstrated that, when reconstructing the resonant state of a weakly bound nucleus, the contamination resulting from the core knockout mechanism should be eliminated in order to obtain the correct structure information.

Characteristics of a 4-fold segmented clover detectore

Differential cross sections for the quasi-elastic scattering of C-16 at 47.5 MeV/nucleon from C-12 target are measured. Coupled-channels calculations are carried out and the optical potential parameters are obtained by fitting the experimental angular distribution.

Configuration of the valence neutrons of ~(17)B

The model of three-body Borromean halo nuclei breakup was described by using standard phase space distributions and the Monte Carlo simulation method was established to resolve the detection problem of two neutrons produced from breakup reaction on the neutron wall detector. For 6He case, overall resolution σEk for the Gaussian part of the detector response and the detection efficiency including solid angle acceptance with regard to the excitation energy Ek are obtained by the simulation of two neutrons from 6He breakup into the neutron wall. The effects of the algorithm on the angular and energy correlations of the fragments are briefly discussed.

HIRFL-CSR ETF多層CSI(TL)望遠鏡検出器のエネルギースケール法【JST・京大機械翻訳】

A time-of-flight system with a plastic scintillator coupled to photomultipliers is developed for the external target facility (ETF). This system can satisfy the requirement of an ultrahigh vacuum (~10−9 mbar), a high counting rate (~106 particles per second) and a magnetic field environment. In the beam test experiment, a total time resolution of 580 ps FWHM was obtained for the whole system, and nuclei with a mass of up to 80 could be identified using this system.A time-of-flight system with a plastic scintillator coupled to photomultipliers is developed for the external target facility (ETF). This system can satisfy the requirement of an ultrahigh vacuum (