Browsing by Author "C. Li"

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    Characteristics of complementary ring-resonator add/drop filters modeling by using graphical approach
    (2007-04-01) P. P. Yupapin; P. Saeung; C. Li; Mahidol University; Harbin Institute of Technology
    In this paper, the filtering characteristics of the two kinds of complementary ring-resonator add/drop filters are modeled and investigated. A graphical approach with signal flow graph is employed here for the analytical derivation of the optical transfer functions in Z-domain of filters. The characteristics of the complementary circuits including the transmittance and group delay of the drop port with respect to the input port are simulated. The present analysis is restricted to directional couplers characterized by two parameters, the power coupling coefficient κ and power coupling loss γ. Explicit expressions for the phase delay, the full-width at half maximum, the Q-factor and the finesse are also given. Using appropriate coupling coefficients, the filtering characteristics can be optimized. © 2006 Elsevier B.V. All rights reserved.
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    Construction and on-site performance of the LHAASO WFCTA camera
    (2021-07-01) F. Aharonian; Q. An; Axikegu; L. X. Bai; Y. X. Bai; Y. W. Bao; D. Bastieri; X. J. Bi; Y. J. Bi; H. Cai; J. T. Cai; Z. Cao; Z. Cao; J. Chang; J. F. Chang; X. C. Chang; B. M. Chen; J. Chen; L. Chen; L. Chen; L. Chen; M. J. Chen; M. L. Chen; Q. H. Chen; S. H. Chen; S. Z. Chen; T. L. Chen; X. L. Chen; Y. Chen; N. Cheng; Y. D. Cheng; S. W. Cui; X. H. Cui; Y. D. Cui; B. Z. Dai; H. L. Dai; Z. G. Dai; Danzengluobu; D. della Volpe; B. D’Ettorre Piazzoli; X. J. Dong; J. H. Fan; Y. Z. Fan; Z. X. Fan; J. Fang; K. Fang; C. F. Feng; L. Feng; S. H. Feng; Y. L. Feng; B. Gao; C. D. Gao; Q. Gao; W. Gao; M. M. Ge; L. S. Geng; G. H. Gong; Q. B. Gou; M. H. Gu; J. G. Guo; X. L. Guo; Y. Q. Guo; Y. Y. Guo; Y. A. Han; H. H. He; H. N. He; J. C. He; S. L. He; X. B. He; Y. He; M. Heller; Y. K. Hor; C. Hou; X. Hou; H. B. Hu; S. Hu; S. C. Hu; X. J. Hu; D. H. Huang; Q. L. Huang; W. H. Huang; X. T. Huang; Z. C. Huang; F. Ji; X. L. Ji; H. Y. Jia; K. Jiang; Z. J. Jiang; C. Jin; D. Kuleshov; K. Levochkin; B. B. Li; C. Li; C. Li; F. Li; H. B. Li; H. C. Li; H. Y. Li; J. Li; K. Li; State Key Laboratory of Particle Detection & Electronics; Nanjing University; Shanghai Astronomical Observatory Chinese Academy of Sciences; Institute for Nuclear Research of the Russian Academy of Sciences; Shandong University; Wuhan University; Yunnan University; Institute of High Energy Physics Chinese Academy of Science; University of Chinese Academy of Sciences; Guangzhou University; Tsinghua University; Sun Yat-Sen University; University of Science and Technology of China; Zhengzhou University; Dublin Institute for Advanced Studies; Università degli Studi di Napoli Federico II; Sichuan University; National Astronomical Observatories Chinese Academy of Sciences; Max-Planck-Institut für Kernphysik; Southwest Jiaotong University; Purple Mountain Observatory Chinese Academy of Sciences; Université de Genève; Hebei Normal University; Tibet University; TIANFU Cosmic Ray Research Center
    The focal plane camera is the core component of the Wide Field-of-view Cherenkov/fluorescence Telescope Array (WFCTA) of the Large High-Altitude Air Shower Observatory (LHAASO). Because of the capability of working under moonlight without aging, silicon photomultipliers (SiPM) have been proven to be not only an alternative but also an improvement to conventional photomultiplier tubes (PMT) in this application. Eighteen SiPM-based cameras with square light funnels have been built for WFCTA. The telescopes have collected more than 100 million cosmic ray events and preliminary results indicate that these cameras are capable of working under moonlight. The characteristics of the light funnels and SiPMs pose challenges (e.g. dynamic range, dark count rate, assembly techniques). In this paper, we present the design features, manufacturing techniques and performances of these cameras. Finally, the test facilities, the test methods and results of SiPMs in the cameras are reported here.
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    Deferasirox in iron-overloaded patients with transfusion-dependent myelodysplastic syndromes: Results from the large 1-year EPIC study
    (2010-09-01) Norbert Gattermann; Carlo Finelli; Matteo Della Porta; Pierre Fenaux; Arnold Ganser; Agnes Guerci-Bresler; Mathias Schmid; Kerry Taylor; Dominique Vassilieff; Dany Habr; Gabor Domokos; Bernard Roubert; Christian Rose; L. Agaoglu; G. Alimena; D. Alonso; S. Ame; E. Angelucci; B. Arrizabalaga; M. Athanasiou-Metaxa; B. Augustson; Y. Aydinok; A. Baba; M. Baccarani; J. Beck; P. Beris; O. Beyne-Rauzy; H. Birgens; D. Bordessoule; C. Borgna-Pignatti; A. Bosly; K. Bouabdallah; D. Bowden; D. Bowen; D. Bron; M. D. Cappellini; M. Capra; G. Cartron; M. Cazzola; C. Chalkias; L. L. Chan; S. Chancharunee; C. Chapman; P. Charoenkwan; E. Chasapopoulou; S. Cheze; A. Chuansumrit; P. Cianciulli; C. Dauriac; M. Delforge; G. Dölken; H. Dombret; J. Duyster; T. Economopoulos; G. Ehninger; M. Elalfy; A. El-Beshlawy; L. Enggaard; G. Fillet; A. Filosa; G. Forni; R. Galanello; G. Gastl; S. Giraudier; A. Goldfarb; A. Grigg; F. Gumruk; S. Y. Ha; D. Haase; B. Heinrich; M. Hertzberg; J. Ho; H. C. Hsu; S. Huang; M. Hunault-Berger; B. Inusa; D. Jaulmes; J. Jensen; A. Kattamis; Y. Kilinc; K. H. Kim; S. Kinsey; L. Kjeldsen; A. Koren; M. E. Lai; Y. Lai; J. W. Lee; K. H. Lee; S. H. Lee; L. Legros; C. Li; C. K. Li; Q. Li; K. H. Lin; W. Linkesch; M. Lübbert; D. Lutz; A. J. Mohamed Thalha; G. Mufti; P. Muus; Heinrich Heine Universitat; Alma Mater Studiorum Universita di Bologna; Universita degli Studi di Pavia; Hopital Avicenne; Medizinische Hochschule Hannover (MHH); Hopital Brabois Adultes; Universitatsklinikum Ulm; Mater Hospital; Universite Paris Descartes; Novartis Pharmaceuticals; Novartis International AG; Hopital Saint Vincent-de-Paul GHICL; Istanbul Universitesi; Azienda Policlinico Umberto I; Hospital Universitario Virgen del Rocio; Hopital de Hautepierre; Azienda Ospedaliera Brotzu - Businco; Hospital de Cruzes; Aristotle University of Thessaloniki; Sir Charles Gairdner Hospital; Ege Universitesi; Hospital Universiti Sains Malaysia; Osp. Bologna; Klinikum der Johannes-Gutenberg-Universitat und Fachbereich Medizin; Hopitaux universitaires de Geneve; Hopital Purpan; Amtssygehusetl Herlev; CHU de Limoges; Az. Ospedaliera Universitaria St. Anna; Cliniques Universitaires UCL; CHU Hopitaux de Bordeaux; Monash Medical Centre; Leeds General Infirmary; Institut Jules Bordet; Universita degli Studi di Milano; Ospedale Civico M. Ascoli; Clinique Victor Hugo; Fondazione IRCCS Policlinico San Matteo; Larissa General Hospital; University of Malaya Medical Centre; Mahidol University; Leicester Royal Infirmary; Chiang Mai University; University Hospitalof Thessaloniki AHEPA; Hopital Clemenceau; Ospedale S. Eugenio; Hopital Pontchaillou; KU Leuven– University Hospital Leuven; Ernst-Moritz-Arndt-Universitat Greifswald; Hopital Saint-Louis; Technical University of Munich; University of Athens Medical School; Dresden University Faculty of Medicine and University Hospital Carl Gustav Carus; Ain Shams University; Cairo University; Hillerod Hospital; Centre Hospitalier Universitaire de Liege; Azienda Ospedaliera Di Rilievo Nazionale Antonio Cardarelli; E.O. Ospedali Galliera; Azienda Ospedaliera Brotzu - Microcitemico; Medizinische Universitat Innsbruck; Hopital Henri Mondor; Hadassah University Medical Centre; Royal Melbourne Hospital; Hacettepe Universitesi; Queen Mary Hospital Hong Kong; Universitatsmedizin Gottingen; Gemeinschaftspraxis Brudler/ Heinrich; Westmead Hospital; Royal Prince Alfred Hospital; Veterans General Hospital-Taipei; Guang Zhou Zhong Shan No.2 Hospital; CHU Angers; Evelina Children's Hospital; Hopital Saint-Antoine; Aarhus Amtssygehus, Aarhus University Hospital; University of Athens; Cukurova Universitesi; Samsung Medical Center, Sungkyunkwan University; St James's University Hospital; Rigshospitalet; Emek Medical Center; Hospital of Nanjing Medical University; The Catholic University of Korea; Asan Medical Center; Royal Adelaide Hospital; Centre Hospitalier Universitaire de Nice, Hopital l'Archet; Nanfang Hospital; Prince of Wales Hospital Hong Kong; Branch of Shanghai No.1 Hospital; National Taiwan University Hospital; LKH-Universitatsklinikum Graz; Universitats Klinikum Freiburg und Medizinische Fakultat; A. Ö. Krankenhausder Elisabethinen; Hospital Universiti Kebangsaan Malaysia; King's College Hospital NHS Foundation Trust; Radboud University Nijmegen Medical Centre
    The prospective 1-year EPIC study enrolled 341 patients with myelodysplastic syndromes (MDS); although baseline iron burden was >2500. ng/mL, ∼50% were chelation-naïve. Overall median serum ferritin decreased significantly at 1 year (p=0.002). Decreases occurred irrespective of whether patients were chelation-naïve or previously chelated; changes were dependent on dose adjustments and ongoing iron intake. Sustained reductions in labile plasma iron were observed. Discontinuation rate (48.7%) and adverse event profile were consistent with previously reported deferasirox data in MDS. Alanine aminotransferase levels decreased significantly; change correlated significantly with reduction in serum ferritin (p<0.0001). This large dataset prospectively confirms the efficacy and well characterizes the safety profile of deferasirox in MDS. © 2010 Elsevier Ltd.
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    A dynamic range extension system for LHAASO WCDA-1
    (2021-12-01) F. Aharonian; Q. An; Axikegu; L. X. Bai; Y. X. Bai; Y. W. Bao; D. Bastieri; X. J. Bi; Y. J. Bi; H. Cai; J. T. Cai; Z. Cao; Z. Cao; J. Chang; J. F. Chang; X. C. Chang; B. M. Chen; J. Chen; L. Chen; L. Chen; L. Chen; M. J. Chen; M. L. Chen; Q. H. Chen; S. H. Chen; S. Z. Chen; T. L. Chen; X. L. Chen; Y. Chen; N. Cheng; Y. D. Cheng; S. W. Cui; X. H. Cui; Y. D. Cui; B. Z. Dai; H. L. Dai; Z. G. Dai; Danzengluobu; D. della Volpe; B. D’Ettorre Piazzoli; X. J. Dong; J. H. Fan; Y. Z. Fan; Z. X. Fan; J. Fang; K. Fang; C. F. Feng; L. Feng; S. H. Feng; Y. L. Feng; B. Gao; C. D. Gao; Q. Gao; W. Gao; M. M. Ge; L. S. Geng; G. H. Gong; Q. B. Gou; M. H. Gu; J. G. Guo; X. L. Guo; Y. Q. Guo; Y. Y. Guo; Y. A. Han; H. H. He; H. N. He; J. C. He; S. L. He; X. B. He; Y. He; M. Heller; Y. K. Hor; C. Hou; X. Hou; H. B. Hu; S. Hu; S. C. Hu; X. J. Hu; D. H. Huang; Q. L. Huang; W. H. Huang; X. T. Huang; Y. Huang; Z. C. Huang; F. Ji; X. L. Ji; H. Y. Jia; K. Jiang; Z. J. Jiang; C. Jin; D. Kuleshov; K. Levochkin; B. B. Li; C. Li; C. Li; F. Li; H. B. Li; H. C. Li; H. Y. Li; J. Li; State Key Laboratory of Particle Detection & Electronics; Nanjing University; Shanghai Astronomical Observatory Chinese Academy of Sciences; Institute for Nuclear Research of the Russian Academy of Sciences; Shandong University; Wuhan University; Yunnan University; Institute of High Energy Physics Chinese Academy of Science; University of Chinese Academy of Sciences; Guangzhou University; Tsinghua University; Sun Yat-Sen University; University of Science and Technology of China; Zhengzhou University; Dublin Institute for Advanced Studies; Università degli Studi di Napoli Federico II; Sichuan University; National Astronomical Observatories Chinese Academy of Sciences; Max-Planck-Institut für Kernphysik; Southwest Jiaotong University; Purple Mountain Observatory Chinese Academy of Sciences; Université de Genève; Hebei Normal University; Tibet University; TIANFU Cosmic Ray Research Center
    Purpose: The main scientific goal of LHAASO-WCDA is to survey gamma-ray sources with energy from 100 GeV to 30 TeV. To observe high-energy shower events, especially to measure the energy spectrum of cosmic rays from 100 TeV to 10 PeV, a dynamic range extension system (WCDA++) is designed to use a 1.5-inch PMT with a dynamic range of four orders of magnitude for each cell in WCDA-1. Method: The dynamic range is extended by using these PMTs to measure the effective charge density in the core region of air shower events, which is an important parameter for identifying the composition of primary particles. Result and Conclusion: The system has been running for more than one year. In this paper, the details of the design and performance of WCDA++ are presented.
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    Extended Very-High-Energy Gamma-Ray Emission Surrounding PSR J0622+3749 Observed by LHAASO-KM2A
    (2021-06-18) F. Aharonian; Q. An; Axikegu; L. X. Bai; Y. X. Bai; Y. W. Bao; D. Bastieri; X. J. Bi; Y. J. Bi; H. Cai; J. T. Cai; Z. Cao; Z. Cao; J. Chang; J. F. Chang; X. C. Chang; B. M. Chen; J. Chen; L. Chen; L. Chen; L. Chen; M. J. Chen; M. L. Chen; Q. H. Chen; S. H. Chen; S. Z. Chen; T. L. Chen; X. L. Chen; Y. Chen; N. Cheng; Y. D. Cheng; S. W. Cui; X. H. Cui; Y. D. Cui; B. Z. Dai; H. L. Dai; Z. G. Dai; Danzengluobu; D. Della Volpe; B. D'Ettorre Piazzoli; X. J. Dong; J. H. Fan; Y. Z. Fan; Z. X. Fan; J. Fang; K. Fang; C. F. Feng; L. Feng; S. H. Feng; Y. L. Feng; B. Gao; C. D. Gao; Q. Gao; W. Gao; M. M. Ge; L. S. Geng; G. H. Gong; Q. B. Gou; M. H. Gu; J. G. Guo; X. L. Guo; Y. Q. Guo; Y. Y. Guo; Y. A. Han; H. H. He; H. N. He; J. C. He; S. L. He; X. B. He; Y. He; M. Heller; Y. K. Hor; C. Hou; X. Hou; H. B. Hu; S. Hu; S. C. Hu; X. J. Hu; D. H. Huang; Q. L. Huang; W. H. Huang; X. T. Huang; Z. C. Huang; F. Ji; X. L. Ji; H. Y. Jia; K. Jiang; Z. J. Jiang; C. Jin; D. Kuleshov; K. Levochkin; B. B. Li; C. Li; C. Li; F. Li; H. B. Li; H. C. Li; H. Y. Li; J. Li; K. Li; State Key Laboratory of Particle Detection & Electronics; Nanjing University; Shanghai Astronomical Observatory Chinese Academy of Sciences; Institute for Nuclear Research of the Russian Academy of Sciences; Shandong University; Wuhan University; Yunnan University; Institute of High Energy Physics Chinese Academy of Science; University of Chinese Academy of Sciences; Guangzhou University; Tsinghua University; Sun Yat-Sen University; University of Science and Technology of China; Zhengzhou University; Dublin Institute for Advanced Studies; Università degli Studi di Napoli Federico II; Sichuan University; National Astronomical Observatories Chinese Academy of Sciences; Max-Planck-Institut für Kernphysik; Southwest Jiaotong University; Purple Mountain Observatory Chinese Academy of Sciences; Université de Genève; Hebei Normal University; Tibet University; TIANFU Cosmic Ray Research Center
    We report the discovery of an extended very-high-energy (VHE) gamma-ray source around the location of the middle-aged (207.8 kyr) pulsar PSR J0622+3749 with the Large High-Altitude Air Shower Observatory (LHAASO). The source is detected with a significance of 8.2σ for E>25 TeV assuming a Gaussian template. The best-fit location is (right ascension, declination) =(95.47°±0.11°,37.92°±0.09°), and the extension is 0.40°±0.07°. The energy spectrum can be described by a power-law spectrum with an index of -2.92±0.17stat±0.02sys. No clear extended multiwavelength counterpart of the LHAASO source has been found from the radio to sub-TeV bands. The LHAASO observations are consistent with the scenario that VHE electrons escaped from the pulsar, diffused in the interstellar medium, and scattered the interstellar radiation field. If interpreted as the pulsar halo scenario, the diffusion coefficient, inferred for electrons with median energies of ∼160 TeV, is consistent with those obtained from the extended halos around Geminga and Monogem and much smaller than that derived from cosmic ray secondaries. The LHAASO discovery of this source thus likely enriches the class of so-called pulsar halos and confirms that high-energy particles generally diffuse very slowly in the disturbed medium around pulsars.
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    Geometrical reconstruction of fluorescence events observed by the LHAASO experiment
    (2021-04-01) F. Aharonian; Q. An; Axikegu; L. X. Bai; Y. X. Bai; Y. W. Bao; D. Bastieri; X. J. Bi; Y. J. Bi; H. Cai; J. T. Cai; Z. Cao; Z. Cao; J. Chang; J. F. Chang; X. C. Chang; B. M. Chen; J. Chen; L. Chen; L. Chen; L. Chen; M. J. Chen; M. L. Chen; Q. H. Chen; S. H. Chen; S. Z. Chen; T. L. Chen; X. L. Chen; Y. Chen; N. Cheng; Y. D. Cheng; S. W. Cui; X. H. Cui; Y. D. Cui; B. Z. Dai; H. L. Dai; Z. G. Dai; Danzengluobu; D. Della Volpe; B. D.Ettorre Piazzoli; X. J. Dong; J. H. Fan; Y. Z. Fan; Z. X. Fan; J. Fang; K. Fang; C. F. Feng; L. Feng; S. H. Feng; Y. L. Feng; B. Gao; C. D. Gao; Q. Gao; W. Gao; M. M. Ge; L. S. Geng; G. H. Gong; Q. B. Gou; M. H. Gu; J. G. Guo; X. L. Guo; Y. Q. Guo; Y. Y. Guo; Y. A. Han; H. H. He; H. N. He; J. C. He; S. L. He; X. B. He; Y. He; M. Heller; Y. K. Hor; C. Hou; X. Hou; H. B. Hu; S. Hu; S. C. Hu; X. J. Hu; D. H. Huang; Q. L. Huang; W. H. Huang; X. T. Huang; Z. C. Huang; F. Ji; X. L. Ji; H. Y. Jia; K. Jiang; Z. J. Jiang; C. Jin; D. Kuleshov; K. Levochkin; B. B. Li; C. Li; C. Li; F. Li; H. B. Li; H. C. Li; H. Y. Li; J. Li; K. Li; State Key Laboratory of Particle Detection & Electronics; Nanjing University; Shanghai Astronomical Observatory Chinese Academy of Sciences; Institute for Nuclear Research of the Russian Academy of Sciences; Shandong University; Wuhan University; Yunnan University; Institute of High Energy Physics Chinese Academy of Science; University of Chinese Academy of Sciences; Guangzhou University; Tsinghua University; Sun Yat-Sen University; University of Science and Technology of China; Zhengzhou University; Dublin Institute for Advanced Studies; Università degli Studi di Napoli Federico II; Sichuan University; National Astronomical Observatories Chinese Academy of Sciences; Max-Planck-Institut für Kernphysik; Southwest Jiaotong University; Purple Mountain Observatory Chinese Academy of Sciences; Université de Genève; Hebei Normal University; Tibet University; TIANFU Cosmic Ray Research Center
    The LHAASO-WFCTA experiment, which aims to observe cosmic rays in the sub-EeV range using the fluorescence technique, uses a new generation of high-performance telescopes. To ensure that the experiment has excellent detection capability associated with the measurement of the energy spectrum, the primary composition of cosmic rays, and so on, an accurate geometrical reconstruction of air-shower events is fundamental. This paper describes the development and testing of geometrical reconstruction for stereo viewed events using the WFCTA (Wide Field of view Cherenkov/Fluorescence Telescope Array) detectors. Two approaches, which take full advantage of the WFCTA detectors, are investigated. One is the stereo-angular method, which uses the pointing of triggered SiPMs in the shower trajectory, and the other is the stereo-timing method, which uses the triggering time of the fired SiPMs. The results show that both methods have good geometrical resolution; the resolution of the stereo-timing method is slightly better than the stereo-angular method because the resolution of the latter is slightly limited by the shower track length.
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    Line-of-shower trigger method to lower energy threshold for GRB detection using LHAASO-WCDA
    (2021-12-01) F. Aharonian; Q. An; Axikegu; L. X. Bai; Y. X. Bai; Y. W. Bao; D. Bastieri; X. J. Bi; Y. J. Bi; H. Cai; J. T. Cai; Z. Cao; Z. Cao; J. Chang; J. F. Chang; X. C. Chang; B. M. Chen; J. Chen; L. Chen; L. Chen; L. Chen; M. J. Chen; M. L. Chen; Q. H. Chen; S. H. Chen; S. Z. Chen; T. L. Chen; X. L. Chen; Y. Chen; N. Cheng; Y. D. Cheng; S. W. Cui; X. H. Cui; Y. D. Cui; B. Z. Dai; H. L. Dai; Z. G. Dai; Danzengluobu; D. della Volpe; B. D’Ettorre Piazzoli; X. J. Dong; J. H. Fan; Y. Z. Fan; Z. X. Fan; J. Fang; K. Fang; C. F. Feng; L. Feng; S. H. Feng; Y. L. Feng; B. Gao; C. D. Gao; Q. Gao; W. Gao; M. M. Ge; L. S. Geng; G. H. Gong; Q. B. Gou; M. H. Gu; J. G. Guo; X. L. Guo; Y. Q. Guo; Y. Y. Guo; Y. A. Han; H. H. He; H. N. He; J. C. He; S. L. He; X. B. He; Y. He; M. Heller; Y. K. Hor; C. Hou; X. Hou; H. B. Hu; S. Hu; S. C. Hu; X. J. Hu; D. H. Huang; Q. L. Huang; W. H. Huang; X. T. Huang; Z. C. Huang; F. Ji; X. L. Ji; H. Y. Jia; K. Jiang; Z. J. Jiang; C. Jin; D. Kuleshov; K. Levochkin; B. B. Li; C. Li; C. Li; F. Li; H. B. Li; H. C. Li; H. Y. Li; J. Li; K. Li; State Key Laboratory of Particle Detection & Electronics; Nanjing University; Shanghai Astronomical Observatory Chinese Academy of Sciences; Institute for Nuclear Research of the Russian Academy of Sciences; Shandong University; Wuhan University; Yunnan University; Institute of High Energy Physics Chinese Academy of Science; University of Chinese Academy of Sciences; Guangzhou University; Tsinghua University; Sun Yat-Sen University; University of Science and Technology of China; Zhengzhou University; Dublin Institute for Advanced Studies; Università degli Studi di Napoli Federico II; Sichuan University; National Astronomical Observatories Chinese Academy of Sciences; Max-Planck-Institut für Kernphysik; Southwest Jiaotong University; Purple Mountain Observatory Chinese Academy of Sciences; Université de Genève; Hebei Normal University; Tibet University; TIANFU Cosmic Ray Research Center
    Purpose: Observation of high energy and very high emission from Gamma Ray Bursts (GRBs) is crucial to study the gigantic explosion and the underline processes. With a large field-of-view and almost full duty cycle, the Water Cherenkov Detector Array (WCDA), a sub-array of the Large High Altitude Air Shower Observatory (LHAASO), is appropriate to monitor the very high energy emission from unpredictable transients such as GRBs. Method: Nevertheless, the main issue for an extensive air shower array is the high energy threshold which limits the horizon of the detector. To address this issue a new trigger method is developed in this article to lower the energy threshold of WCDA for GRB observation. Result: The proposed method significantly improves the detection efficiency of WCDA for gamma-rays around the GRB direction at 10-300 GeV. The sensitivity of the WCDA for GRB detection with the new trigger method is estimated. The achieved sensitivity of the quarter WCDA array above 10 GeV is comparable with that of Fermi-LAT. The data analysis process and corresponding fluence upper limit for GRB 190719C is presented as an example.
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    Neutralizing antibodies against adeno-associated virus examined prospectively in pediatric patients with hemophilia
    (2012-03-01) C. Li; N. Narkbunnam; R. J. Samulski; A. Asokan; G. Hu; L. J. Jacobson; M. J. Manco-Johnson; P. E. Monahan; Marilyn J. Manco-Johnson; Brenda Riske; Ray Kilcoyne; Michael L. Manco-Johnson; Sharon Funk; Linda Jacobson; J. David Ingram; Thomas C. Abshire; Amy D. Shapiro; Michele R. Hacker; Leonard A. Valentino; W. Keith Hoots; Deborah Brown; George R. Buchanan; Donna DiMichele; Michael Recht; Cindy Leissinger; Shirley Bleak; Alan Cohen; Prasad Mathew; Alison Matsunaga; Desiree Medeiros; Diane Nugent; Gregory A. Thomas; Alexis A. Thompson; Kevin McRedmond; J. Michael Soucie; Harlan Austin; Bruce L. Evatt; The University of North Carolina at Chapel Hill; Mahidol University; University of Colorado School of Medicine; University of Colorado Health Sciences Center; Emory University; Blood Center of Milwaukee; Indiana Hemophilia and Thrombosis Center; Harvard Medical School; Rush University Medical Center; University of Texas System; University of Southwestern Medical Center; Weill Cornell Medical College; Phoenix Children's Hospital; Tulane University; Primary Children's Medical Center; University of Pennsylvania; University of New Mexico; UCSF Benioff Children's Hospital Oakland; University of Hawaii at Manoa; CHOC Children`s UC Irvine School of Medicine; Oregon Health and Science University; Northwestern University; Palmetto Health Richland; Centers for Disease Control and Prevention
    Recombinant adeno-associated virus (rAAV) is a promising gene delivery vector and has recently been used in patients with hemophilia. One limitation of AAV application is that most humans have experienced wild-type AAV serotype 2 exposure, which frequently generates neutralizing antibodies (NAbs) that may inhibit rAAV2 vector transduction. Employing alternative serotypes of rAAV vectors may circumvent this problem. We investigated the development of NAbs in early childhood by examining sera gathered prospectively from 62 children with hemophilia A, participating in a multi-institutional hemophilia clinical trial (the Joint Outcome Study). Clinical applications in hemophilia therapy have been suggested for serotypes AAV2, AAV5 and AAV8, therefore NAbs against these serotypes were serially assayed over a median follow-up of 4 years. NAbs prevalence increased during early childhood for all serotypes. NAbs against AAV2 (43.5%) were observed more frequently and at higher titers compared with both AAV5 (25.8%) and AAV8 (22.6%). NAbs against AAV5 or AAV8 were rarely observed in the absence of co-prevalent and higher titer AAV2 NAbs, suggesting that NAbs to AAV5 and AAV8 were detected following AAV2 exposure due to partial cross-reactivity of AAV2-directed NAbs. The results may guide rational design of clinical trials using alternative AAV serotypes and suggest that younger patients who are given AAV gene therapy will benefit from the lower prevalence of NAbs. © 2012 Macmillan Publishers Limited All rights reserved.
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    Observation of the Crab Nebula with LHAASO-KM2A - A performance study
    (2021-02-01) F. Aharonian; Q. An; Axikegu; L. X. Bai; Y. X. Bai; Y. W. Bao; D. Bastieri; X. J. Bi; Y. J. Bi; H. Cai; J. T. Cai; Z. Cao; J. Chang; J. F. Chang; X. C. Chang; B. M. Chen; J. Chen; L. Chen; L. Chen; L. Chen; M. J. Chen; M. L. Chen; Q. H. Chen; S. H. Chen; S. Z. Chen; T. L. Chen; X. L. Chen; Y. Chen; N. Cheng; Y. D. Cheng; S. W. Cui; X. H. Cui; Y. D. Cui; B. Z. Dai; H. L. Dai; Z. G. Dai; Danzengluobu; D. Della Volpe; B. D.Ettorre Piazzoli; X. J. Dong; J. H. Fan; Y. Z. Fan; Z. X. Fan; J. Fang; K. Fang; C. F. Feng; L. Feng; S. H. Feng; Y. L. Feng; B. Gao; C. D. Gao; Q. Gao; W. Gao; M. M. Ge; L. S. Geng; G. H. Gong; Q. B. Gou; M. H. Gu; J. G. Guo; X. L. Guo; Y. Q. Guo; Y. Y. Guo; Y. A. Han; H. H. He; H. N. He; J. C. He; S. L. He; X. B. He; Y. He; M. Heller; Y. K. Hor; C. Hou; X. Hou; H. B. Hu; S. Hu; S. C. Hu; X. J. Hu; D. H. Huang; Q. L. Huang; W. H. Huang; X. T. Huang; Z. C. Huang; F. Ji; X. L. Ji; H. Y. Jia; K. Jiang; Z. J. Jiang; C. Jin; D. Kuleshov; K. Levochkin; B. B. Li; C. Li; C. Li; F. Li; H. B. Li; H. C. Li; H. Y. Li; J. Li; K. Li; W. L. Li; State Key Laboratory of Particle Detection & Electronics; Nanjing University; Shanghai Astronomical Observatory Chinese Academy of Sciences; Institute for Nuclear Research of the Russian Academy of Sciences; Shandong University; Wuhan University; Yunnan University; Institute of High Energy Physics Chinese Academy of Science; University of Chinese Academy of Sciences; Guangzhou University; Tsinghua University; Sun Yat-Sen University; University of Science and Technology of China; Zhengzhou University; Dublin Institute for Advanced Studies; Università degli Studi di Napoli Federico II; Sichuan University; National Astronomical Observatories Chinese Academy of Sciences; Max-Planck-Institut für Kernphysik; Southwest Jiaotong University; Purple Mountain Observatory Chinese Academy of Sciences; Université de Genève; Hebei Normal University; Tibet University; TIANFU Cosmic Ray Research Center
    A sub-array of the Large High Altitude Air Shower Observatory (LHAASO), KM2A is mainly designed to observe a large fraction of the northern sky to hunt for γ-ray sources at energies above 10 TeV. Even though the detector construction is still underway, half of the KM2A array has been operating stably since the end of 2019. In this paper, we present the KM2A data analysis pipeline and the first observation of the Crab Nebula, a standard candle in very high energy γ-ray astronomy. We detect γ-ray signals from the Crab Nebula in both energy ranges of 10-100 TeV and >100 TeV with high significance, by analyzing the KM2A data of 136 live days between December 2019 and May 2020. With the observations, we test the detector performance, including angular resolution, pointing accuracy and cosmic-ray background rejection power. The energy spectrum of the Crab Nebula in the energy range 10-250 TeV fits well with a single power-law function dN/dE = (1.13±0.05stat±0.08sys)×10-14 (E/20 TeV)-3.09±0.06stat±0.02sys cm-2 s-1 TeV-1. It is consistent with previous measurements by other experiments. This opens a new window of γ-ray astronomy above 0.1 PeV through which new ultrahigh-energy γ-ray phenomena, such as cosmic PeVatrons, might be discovered.
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    Performance of LHAASO-WCDA and observation of the Crab Nebula as a standard candle
    (2021-08-01) F. Aharonian; Q. An; Axikegu; L. X. Bai; Y. X. Bai; Y. W. Bao; D. Bastieri; X. J. Bi; Y. J. Bi; H. Cai; J. T. Cai; Z. Cao; J. Chang; J. F. Chang; X. C. Chang; B. M. Chen; J. Chen; L. Chen; M. J. Chen; M. L. Chen; Q. H. Chen; S. H. Chen; S. Z. Chen; T. L. Chen; X. L. Chen; Y. Chen; N. Cheng; Y. D. Cheng; S. W. Cui; X. H. Cui; Y. D. Cui; B. Z. Dai; H. L. Dai; Z. G. Dai; Danzengluobu; D. della Volpe; B. D'Ettorre Piazzoli; X. J. Dong; J. H. Fan; Y. Z. Fan; Z. X. Fan; J. Fang; K. Fang; C. F. Feng; L. Feng; S. H. Feng; Y. L. Feng; B. Gao; C. D. Gao; Q. Gao; W. Gao; M. M. Ge; L. S. Geng; G. H. Gong; Q. B. Gou; M. H. Gu; J. G. Guo; X. L. Guo; Y. Q. Guo; Y. Y. Guo; Y. A. Han; H. H. He; H. N. He; J. C. He; S. L. He; X. B. He; Y. He; M. Heller; Y. K. Hor; C. Hou; X. Hou; H. B. Hu; S. Hu; S. C. Hu; X. J. Hu; D. H. Huang; Q. L. Huang; W. H. Huang; X. T. Huang; Z. C. Huang; F. Ji; X. L. Ji; H. Y. Jia; K. Jiang; Z. J. Jiang; C. Jin; D. Kuleshov; K. Levochkin; B. B. Li; C. Li; F. Li; H. B. Li; H. C. Li; H. Y. Li; J. Li; K. Li; W. L. Li; X. Li; X. R. Li; Y. Li; State Key Laboratory of Particle Detection & Electronics; Nanjing University; Shanghai Astronomical Observatory Chinese Academy of Sciences; Institute for Nuclear Research of the Russian Academy of Sciences; Shandong University; Wuhan University; Yunnan University; Institute of High Energy Physics Chinese Academy of Science; University of Chinese Academy of Sciences; Guangzhou University; Tsinghua University; Sun Yat-Sen University; University of Science and Technology of China; Zhengzhou University; Dublin Institute for Advanced Studies; Università degli Studi di Napoli Federico II; Sichuan University; National Astronomical Observatories Chinese Academy of Sciences; Max-Planck-Institut für Kernphysik; Southwest Jiaotong University; Purple Mountain Observatory Chinese Academy of Sciences; Université de Genève; Hebei Normal University; Tibet University; TIANFU Cosmic Ray Research Center
    The first Water Cherenkov detector of the LHAASO experiment (WCDA-1) has been operating since April 2019. The data for the first year have been analyzed to test its performance by observing the Crab Nebula as a standard candle. The WCDA-1 achieves a sensitivity of 65 mCU per year, with a statistical threshold of 5 σ. To accomplish this, a 97.7% cosmic-ray background rejection rate around 1 TeV and 99.8% around 6 TeV with an approximate photon acceptance of 50% is achieved after applying an algorithm to separate gamma-induced showers. The angular resolution is measured using the Crab Nebula as a point source to be approximately 0.45° at 1 TeV and better than 0.2° above 6 TeV, with a pointing accuracy better than 0.05°. These values all match the design specifications. The energy resolution is found to be 33% for gamma rays around 6 TeV. The spectral energy distribution of the Crab Nebula in the range from 500 GeV to 15.8 TeV is measured and found to be in agreement with the results from other TeV gamma ray observatories.
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    Performance test of the electromagnetic particle detectors for the LHAASO experiment
    (2021-06-11) F. Aharonian; Q. An; Axikegu; L. X. Bai; Y. X. Bai; Y. W. Bao; D. Bastieri; X. J. Bi; Y. J. Bi; H. Cai; J. T. Cai; Z. Cao; J. Chang; J. F. Chang; X. C. Chang; B. M. Chen; J. Chen; L. Chen; M. J. Chen; M. L. Chen; Q. H. Chen; S. H. Chen; S. Z. Chen; T. L. Chen; X. L. Chen; Y. Chen; N. Cheng; Y. D. Cheng; S. W. Cui; X. H. Cui; Y. D. Cui; B. Z. Dai; H. L. Dai; Z. G. Dai; Danzengluobu; D. della Volpe; B. D'Ettorre Piazzoli; X. J. Dong; J. H. Fan; Y. Z. Fan; Z. X. Fan; J. Fang; K. Fang; C. F. Feng; L. Feng; S. H. Feng; Y. L. Feng; B. Gao; C. D. Gao; Q. Gao; W. Gao; M. M. Ge; L. S. Geng; G. H. Gong; Q. B. Gou; M. H. Gu; J. G. Guo; X. L. Guo; Y. Q. Guo; Y. Y. Guo; Y. A. Han; H. H. He; H. N. He; J. C. He; S. L. He; X. B. He; Y. He; M. Heller; Y. K. Hor; C. Hou; X. Hou; H. B. Hu; S. Hu; S. C. Hu; X. J. Hu; D. H. Huang; Q. L. Huang; W. H. Huang; X. T. Huang; Z. C. Huang; F. Ji; X. L. Ji; H. Y. Jia; K. Jia; K. Jiang; Z. J. Jiang; C. Jin; D. Kuleshov; K. Levochkin; B. Li; B. B. Li; C. Li; F. Li; H. Li; H. B. Li; H. C. Li; H. Y. Li; J. Li; K. Li; W. L. Li; State Key Laboratory of Particle Detection & Electronics; Nanjing University; Shanghai Astronomical Observatory Chinese Academy of Sciences; Institute for Nuclear Research of the Russian Academy of Sciences; Shandong University; Wuhan University; Yunnan University; Institute of High Energy Physics Chinese Academy of Science; University of Chinese Academy of Sciences; Yantai University; Guangzhou University; Tsinghua University; Sun Yat-Sen University; University of Science and Technology of China; Zhengzhou University; Dublin Institute for Advanced Studies; Università degli Studi di Napoli Federico II; Sichuan University; National Astronomical Observatories Chinese Academy of Sciences; Max-Planck-Institut für Kernphysik; Southwest Jiaotong University; Purple Mountain Observatory Chinese Academy of Sciences; Université de Genève; Hebei Normal University; Tibet University; TIANFU Cosmic Ray Research Center
    The Large High Altitude Air Shower Observatory (LHAASO) is a new generation hybrid cosmic ray observatory which is expected to reveal the mystery of the origin of cosmic rays. The one square kilometer array (KM2A) consisting of 5195 Electromagnetic particle Detectors (ED) and 1188 Muon Detectors (MD) is a sub-array of LHAASO. The EDs are designed to measure the density and arriving time of the secondary particles of extensive air showers. The performance of the EDs is tested for the quality control after construction in the laboratory at sea level. In this paper, the performance of more than four thousands EDs is summarized. The performance of all tested EDs meets the design requirements with the time resolution of 1.6 ns, the detection efficiency of 97.8%, charge resolution for single particle of 18.5% and count rate around 480 Hz. Furthermore, one ED is singled out for monitoring of the long-term stability over a period of nearly two years from December 2018 to November 2020.