The DArk Matter Particle Explorer(DAMPE) is a space-borne apparatus for detecting the highenergy cosmic-ray-like electrons, γ-rays, protons and heavy ions. The Plastic Scintillator Detector(PSD)is the top-most sub-de...The DArk Matter Particle Explorer(DAMPE) is a space-borne apparatus for detecting the highenergy cosmic-ray-like electrons, γ-rays, protons and heavy ions. The Plastic Scintillator Detector(PSD)is the top-most sub-detector of the DAMPE. The PSD is designed to measure the charge of incident highenergy particles and it also serves as a veto detector for discriminating γ-rays from charged particles. In this paper, a PSD on-orbit calibration procedure is described, which includes the five steps of pedestal, dynode correlation, response to minimum-ionizing particles, light attenuation function and energy reconstruction.A method for reconstructing the charge of incident high energy cosmic-ray particles is introduced. The detection efficiency of each PSD strip is verified to be above 99.5%; the total efficiency of the PSD for charged particles is above 99.99%.展开更多
The DArk Matter Particle Explorer(DAMPE)is a satellite-borne detector for high-energy cosmic rays and y-rays.To fully understand the detector performance and obtain reliable physical results,extensive simulations of t...The DArk Matter Particle Explorer(DAMPE)is a satellite-borne detector for high-energy cosmic rays and y-rays.To fully understand the detector performance and obtain reliable physical results,extensive simulations of the detector are necessary.The simulations are particularly important for the data analysis of cosmic ray nuclei,which relies closely on the hadronic and nuclear interactions of particles in the detector material.Widely adopted simulation softwares include the GEANT4 and FLUKA,both of which have been implemented for the DAMPE simulation tool.Here we describe the simulation tool of DAMPE and compare the results of proton shower properties in the calorimeter from the two simulation softwares.Such a comparison gives an estimate of the most significant uncertainties of our proton spectral analysis.展开更多
This work deals with the deposition of lead (Pb) thin films by the UV pulsed laser ablation technique, for their further use as photocathode devices in superconducting radio frequency guns. Scanning electron microsc...This work deals with the deposition of lead (Pb) thin films by the UV pulsed laser ablation technique, for their further use as photocathode devices in superconducting radio frequency guns. Scanning electron microscopy and atomic force microscopy analyses were performed to study the morphological features of Pb thin films deposited on Si (100) and Nb substrates. The films showed a granular structure with a nearly fully covered surface only for that one deposited on Nb substrate. X-ray diffraction measurements indicate the growth of polycrystalline Pb thin films with a preferential orientation along (111) planes. Results of the photoemission performance of Pb thin film deposited on Nb substrate showed a very encouraging average value of quantum efficiency of 6 x 10-5 through a single-photon absorption process, promoting further studies in the realisation of Pb photocathodes by this technique.展开更多
Semiconductor devices are strong competitors in the race for the development of quantum computational systems.In this work,we interface two semiconductor building blocks of different dimensionalities with complementar...Semiconductor devices are strong competitors in the race for the development of quantum computational systems.In this work,we interface two semiconductor building blocks of different dimensionalities with complementary properties:(1)a quantum dot hosting a single exciton and acting as a nearly ideal single-photon emitter and(2)a quantum well in a 2D microcavity sustaining polaritons,which are known for their strong interactions and unique hydrodynamic properties,including ultrafast real-time monitoring of their propagation and phase mapping.In the present experiment,we can thus observe how the injected single particles propagate and evolve inside the microcavity,giving rise to hydrodynamic features typical of macroscopic systems despite their genuine intrinsic quantum nature.In the presence of a structural defect,we observe the celebrated quantum interference of a single particle that produces fringes reminiscent of wave propagation.While this behavior could be theoretically expected,our imaging of such an interference pattern,together with a measurement of antibunching,constitutes the first demonstration of spatial mapping of the self-interference of a single quantum particle impinging on an obstacle.展开更多
基金funded by the National Key Research and Development Program of China (2016YFA0400201)supported by the National Natural Science Foundation of China (11673047,11673075, 11303107, U1738127 and U1738205)
文摘The DArk Matter Particle Explorer(DAMPE) is a space-borne apparatus for detecting the highenergy cosmic-ray-like electrons, γ-rays, protons and heavy ions. The Plastic Scintillator Detector(PSD)is the top-most sub-detector of the DAMPE. The PSD is designed to measure the charge of incident highenergy particles and it also serves as a veto detector for discriminating γ-rays from charged particles. In this paper, a PSD on-orbit calibration procedure is described, which includes the five steps of pedestal, dynode correlation, response to minimum-ionizing particles, light attenuation function and energy reconstruction.A method for reconstructing the charge of incident high energy cosmic-ray particles is introduced. The detection efficiency of each PSD strip is verified to be above 99.5%; the total efficiency of the PSD for charged particles is above 99.99%.
基金Supported by the National Key Research and Development Program of China(Grant No.2016YFA0400200)the National Natural Science Foundation of China(Grant Nos.11722328,11773085,U1738127,U1738138,U1738205,U1738207,and 11851305)+4 种基金the 100 Talents Program of Chinese Academy of Sciencesthe Youth Innovation Promotion Association CASthe Program for Innovative Talents and Entrepreneur in Jiangsusupported by the Swiss National Science Foundation(SNSF),Switzerlandthe National Institute for Nuclear Physics(INFN),Italy。
文摘The DArk Matter Particle Explorer(DAMPE)is a satellite-borne detector for high-energy cosmic rays and y-rays.To fully understand the detector performance and obtain reliable physical results,extensive simulations of the detector are necessary.The simulations are particularly important for the data analysis of cosmic ray nuclei,which relies closely on the hadronic and nuclear interactions of particles in the detector material.Widely adopted simulation softwares include the GEANT4 and FLUKA,both of which have been implemented for the DAMPE simulation tool.Here we describe the simulation tool of DAMPE and compare the results of proton shower properties in the calorimeter from the two simulation softwares.Such a comparison gives an estimate of the most significant uncertainties of our proton spectral analysis.
基金supported by the Italian National Institute of Nuclear Physics(INFN)
文摘This work deals with the deposition of lead (Pb) thin films by the UV pulsed laser ablation technique, for their further use as photocathode devices in superconducting radio frequency guns. Scanning electron microscopy and atomic force microscopy analyses were performed to study the morphological features of Pb thin films deposited on Si (100) and Nb substrates. The films showed a granular structure with a nearly fully covered surface only for that one deposited on Nb substrate. X-ray diffraction measurements indicate the growth of polycrystalline Pb thin films with a preferential orientation along (111) planes. Results of the photoemission performance of Pb thin film deposited on Nb substrate showed a very encouraging average value of quantum efficiency of 6 x 10-5 through a single-photon absorption process, promoting further studies in the realisation of Pb photocathodes by this technique.
基金the ERC project Elecopter grant number 780757 for financial supportCorrect Systems Lab funded by the state of Upper Austria and the Austrian Science Fund(FWF):P29603 for financial support+2 种基金the project FISR—C.N.R.“Tecnopolo di nanotecnologia e fotonica per la medicina di precisione”-CUP B83B17000010001“Progetto Tecnopolo per la Medicina di precisione,Deliberazione della Giunta Regionale n.2117 del 21/11/2018”the PRIN project Inphopol.
文摘Semiconductor devices are strong competitors in the race for the development of quantum computational systems.In this work,we interface two semiconductor building blocks of different dimensionalities with complementary properties:(1)a quantum dot hosting a single exciton and acting as a nearly ideal single-photon emitter and(2)a quantum well in a 2D microcavity sustaining polaritons,which are known for their strong interactions and unique hydrodynamic properties,including ultrafast real-time monitoring of their propagation and phase mapping.In the present experiment,we can thus observe how the injected single particles propagate and evolve inside the microcavity,giving rise to hydrodynamic features typical of macroscopic systems despite their genuine intrinsic quantum nature.In the presence of a structural defect,we observe the celebrated quantum interference of a single particle that produces fringes reminiscent of wave propagation.While this behavior could be theoretically expected,our imaging of such an interference pattern,together with a measurement of antibunching,constitutes the first demonstration of spatial mapping of the self-interference of a single quantum particle impinging on an obstacle.