Hard X-ray Imager (HXI) is one of the three scientific instruments onboard the Advanced Spacebased Solar Observatory (ASO-S) mission, which is proposed for the 25th solar maximum by the Chinese solar community. HXI is designed to investigate the non-thermal high-energy electrons accelerated in solar flares by providing images of solar flaring regions in the energy range from 30 keV to 200 keV. The imaging principle of HXI is based on spatially modulated Fourier synthesis and utilizes about 91 sets of bi-grid sub-collimators and corresponding LaBr3 detectors to obtain Fourier components with a spatial resolution of about 3 arcsec and a time resolution better than 0.5 s. An engineering prototype has been developed and tested to verify the feasibility of design. In this paper, we present background, instrument design and the development and test status of the prototype.

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Transmission of a quantum state is essential for performing quantum information processing tasks. The communication channel will be inevitably immersed in its surrounding environment under realistic conditions. In this paper, we investigate the influence of environment noise on the transmission fidelity when transferring a quantum state through a spin chain. The non-Markovian open system dynamics is systematically analyzed by using the quantum state diffusion equation method. With each spin immersed in its own finite temperature and non-Markovian heat bath, we consider three types of system–bath interaction: dephasing, dissipation and spin-boson. The transmission fidelity is found to decrease with the increasing bath temperature and system–bath coupling strength. Interestingly, we find that the bath non-Markovianity can help enhancing the transmission fidelity.

The DArk Matter Particle Explorer (DAMPE), one of the four space-based scientific missions within the framework of the Strategic Pioneer Program on Space Science of the Chinese Academy of Sciences, was successfully launched on 2015 Dec. 17 from Jiuquan launch center. One of the most important scientific goals of DAMPE is to search for evidence of dark matter indirectly by measuring the spectrum of high energy cosmic-ray electrons. The neutron detector, one of the four sub-payloads of DAMPE, is designed to distinguish high energy electrons from hadron background by measuring the secondary neutrons produced in the shower. In this paper, a comprehensive introduction of the neutron detector is presented, including the design, calibration and performance. The analysis with simulated data and flight data indicates a powerful proton rejection capability of the neutron detector, which plays an essential role for TeV electron identification of DAMPE.

The energy loss effect in nuclear matter is another nuclear effect apart from the nuclear effects on the parton distribution as in deep inelastic scattering process. The quark energy loss can be measured best by the nuclear dependence of the high energy nuclear Drell-Yan process. By means of three kinds of quark energy loss parameterizations given in literature and the nuclear parton distribution extracted only with lepton-nucleus deep inelastic scattering experimental data, measured Drell-Yan production cross sections are analyzed for 800GeV proton incident on a variety of nuclear targets from FNAL E866. It is shown that our results with considering the energy loss effect are much different from these of the FNAL E866 who analysis the experimental data with the nuclear parton distribution functions obtained by using the deep inelastic lA collisions and pA nuclear Drell-Yan data . Considering the existence of energy loss effect in Drell-Yan lepton pairs production,we suggest that the extraction of nuclear parton distribution functions should not include Drell-Yan experimental data.

The next-to-leading order and leading order analysis are performed on the differential cross section ratio from Drell-Yan process. It is found that the effect of next-to-leading order corrections can be negligible on the differential cross section ratios as a function of the quark momentum fraction in the beam proton and the target nuclei for the current Fermilab and future lower beam proton energy. The nuclear Drell-Yan reaction is an ideal tool to study the energy loss of the fast quark moving through cold nuclei. In the leading order analysis, the theoretical results with quark energy loss are in good agreement with the Fermilab E866 experimental data on the Drell-Yan differential cross section ratios as a function of the momentum fraction of the target parton. It is shown that the quark energy loss effect has significant impact on the Drell-Yan differential cross section ratios. The nuclear Drell-Yan experiment at current Fermilab and future lower energy proton beam can not provide us with more information on the nuclear sea quark distribution.

A new coordination compound [Co(DAT) 6 ](PA) 2 •4H 2 O has been prepared by using 1,5-diaminotetrazole (DAT) as ligands and picrate (PA) as acidic anions, and structurally characterized by X-ray single crystal diffraction, elemental analysis and FT-IR spectroscopy. The cobalt(II) cation coordinates with six N atoms from six bulky DAT molecules to form a six-coordinated and slightly distorted octahedral configuration. The coordination cation is situated between two PA anions whose benzene-ring planes are parallel to each other. The coordination cation and the PA anions are bonded together by electrostatic forces in the molecular unit of [Co(DAT) 6 ](PA) 2 •4H 2 O. All the molecular units are linked together by the intermolecular hydrogen bonds to form the crystal structure, in the formation of which DAT ligand plays an important role. Thermal decomposition processes of [Co(DAT) 6 ](PA) 2 •4H 2 O were investigated by using DSC, TG-DTG and FT-IR analyses. The kinetic parameters of the first exothermic process of the title compound were studied by applying the Kissinger's and Ozawa-Doyle's methods.