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Experimental Advanced Superconducting Tokamak (EAST) aims to demonstrate steady-state advanced high-performance H-mode plasmas with an ITER-like configuration, plasma control and heating schemes. The plasma-facing components in EAST are actively cooled, providing good conditions for researching long-pulse and high-energy discharges. A long-pulse high-performance plasma discharge (#59892 discharge) of up to 103 s with a core electron temperature of up to 4.5 keV was sustained with an injected energy exceeding 0.22 GJ in the 2015–2016 experimental campaign. A calorimetric measurement utilizing the temperature increment of cooling water is carried out to calculate the heat load on the strike point region of the lower divertor during long-pulse discharges in EAST. For the long-pulse and high-energy discharges, the comparison of the measurement results for the heat load measured by divertor Langmuir probes and the calorimetry diagnostic indicates that most of the heat load is delivered to the divertor panels as plasma, not radiation, and charge exchange neutrals. The ratio of the heat load on the strike point region of the lower divertor to the total injected energy is on average 42.5% per discharge with the lower single null divertor configuration. If the radiated energy loss measured by the fast bolometer diagnostic is taken into consideration, the ratio is found to be 61.6%. The experimental results and the analysis of the physics involved in these discharges are reported and discussed. [ABSTRACT FROM AUTHOR]

High-spin states in 86Sr have been investigated by using in-beam γ ray spectroscopy with the 82Se(9Be, 5n)86Sr reaction at a beam energy of 53 MeV. A new dipole sequence has been observed and the mixed configurations of unpaired valence nucleons and before the alignment and the configuration after the alignment are assigned respectively. Shell-model and self-consistent titled axis cranking relativistic mean-field model calculations are performed to interpret the rotational structure and the characteristic features of magnetic rotation have been presented for the sequence. [ABSTRACT FROM AUTHOR]

Lifetimes of excited states above 10+ in the yrast band in 176Os have been measured using the Doppler shift attenuation method, via the fusion evaporation reaction \mathrm{^{152}Sm(^{28}Si, 4\mbox{\mbox{\it n}})^{176}Os}. Lifetimes of states over 12+ were measured for the first time. The deduced transitional quadruple moments (Qt), together with the previous data using a recoil distance method, are compared with theoretical calculations based on the X(5) model and the interaction boson model. For the states below spin 10+, the data of previous work support an X(5)-like structure, but for the states above 10+, the value of Qt remains almost constant, being the characteristic of a symmetric rotor. The present result suggests that the shape of the nucleus 176Os changes from X(5) critical-point symmetry to an axially deformed rotor with increasing spin. [ABSTRACT FROM AUTHOR]