Yunlong Zhang

The calibration and electron energy reconstruction of the BGO ECAL of the DAMPE detector

Abstract The DArk Matter Particle Explorer (DAMPE) is a space experiment designed to search for dark matter indirectly by measuring the spectra of photons, electrons, and positrons up to 10xa0TeV. The BGO electromagnetic calorimeter (ECAL) is its main sub-detector for energy measurement. In this paper, the instrumentation and development of the BGO ECAL is briefly described. The calibration on the ground, including the pedestal, minimum ionizing particle (MIP) peak, dynode ratio, and attenuation length with the cosmic rays and beam particles is discussed in detail. Also, the energy reconstruction results of the electrons from the beam test are presented.

Design of the Readout Electronics for the BGO Calorimeter of DAMPE Mission

The DAMPE (DArk Matter Particle Explorer) is a scientific satellite being developed in China, aimed at cosmic ray study, gamma ray astronomy, and searching for the clue of dark matter particles in the near future. The BGO (Bismuth Germanate Oxide) Calorimeter, which consists of 616 PMTs (photomultiplier tubes) and 1848 dynode signals, is a crucial part of the DAMPE payload for measuring the energy of cosmic ray particles, distinguishing interesting particles from background, and providing trigger information. An electronics system, which consists of 16 FEE (Front End Electronics) modules with a total power consumption of about 26 W, has been developed. Its main functions are based on the low power, 32-channel VA160 and VATA160 ASICs (Application Specific Integrated Circuits) for precisely measuring the charge of PMT signals and providing“hit”signals as well. To assure the long-term reliability in harsh space environment, a series of critical issues such as the radiation hardness, thermal design, components and board level quality control, etc., are taken into consideration. Test result showed that the system level ENC (equivalent noise charge) for each channel is about 10 fC in RMS (root mean square), and the timing uncertainty of the hit signals is about 300 ns, both of which satisfy the physics requirements of the detector. Experiments with 60Co radioactive source proved that 20 krad(Si) TID (Total Ionizing Dose) level is achieved, while the heavy ion beam and laser beam tests indicated that its SEL (Single Event Latch-up) and SEU (Single Event Upset) performance in orbit will be acceptable by taking some hardness measures. All the readout modules successfully passed the board-level screening, the sub-system level and finally the satellite system level environmental tests, and behave well in the beam test at CERN (European Organisation for Nuclear Research).

Study on the temperature dependence of BGO light yield

The temperature dependence of BGO coupled with photomultiplier tube R5610A-01 was studied in the range of −30–30°C. The temperature coefficient of the BGO and R5610A as a whole was tested to be −1.82%/°C. And the temperature coefficient of the gain of the R5610A is −0.44%/°C which was tested in the same situation using a blue LED. Thus the temperature coefficient of BGO’s light yield can be evaluated as −1.38%/°C.

Study of CdMoO4crystal for a neutrinoless double beta decay experiment with116Cd and100Mo nuclides

The scintillation properties of a

A parameterized energy correction method for electromagnetic showers in BGO-ECAL of DAMPE

mathrm{CdMoO_4}

The CBM Time-of-Flight wall — a conceptual design

crystal have been investigated experimentally. The fluorescence yields and decay times measured from 22 K to 300 K demonstrate that

Energy correction for the BGO calorimeter of DAMPE using an electron beam

mathrm{CdMoO_4}

The BGO electromagnetic calorimeter sub-trigger electronics for DAMPE

crystal is a good candidate for an absorber for a bolometer readout, for both heat and scintillation signals. The results from Monte Carlo studies taking the backgrounds from

Temperature Dependence Calibration and Correction of the DAMPE BGO Electromagnetic Calorimeter

mathrm{2nu2beta}

Onboard calibration circuit for the DAMPE BGO calorimeter front-end electronics

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