| Alpha Magnetic Spectrometer(AMS-02)is a particle physics detector on board the International Space Station(ISS),characterised by its large acceptance,long operating time and high measurement accuracy.The AMS-02 is designed to study the origin of dark matter,antimatter and cosmic rays by measuring the composition and energy spectrum of cosmic rays from GeV to TeV.It also provides new experimental information for the study of physical mechanisms related to solar modulation by measuring the variation of cosmic ray flux over time.Cosmic ray positron fluxes are an important experimental tool for the study of dark matter.Low-energy cosmic ray positrons are mainly secondary products of collisions between cosmic rays and the interstellar medium,while high-energy positrons may come from new astrophysical processes such as dark matter or pulsars.Cosmic rays entering the heliosphere are affected by solar activity and the flux varies with time,i.e.the solar modulation effect.The drift effect in the solar modulation process depends on the charge sign and the polarity of the solar magnetic field,and there may be different temporal variations in the flux of positively and negatively charged cosmic rays.Electrons are the most abundant negatively charged particles in cosmic rays,and positrons are the most abundant antimatter particles.Electrons and positrons are a pair of positive and negative particles with the same mass and opposite charge sign.The simultaneous measurement of cosmic ray electrons and positrons is the most direct experimental means of studying the correlation between the charge sign of solar modulation.In this thesis,timely measurements of cosmic ray electron flux and positron flux were performed using a combination of AMS-02 Transition Radiation Detector(TRD),Silicon Tracker Detector(Tracker).Electromagnetic Calorimeter(ECAL)and Time of Flight Counters(TOF).By analysing cosmic ray data collected by AMS-02 between 20 May 2011 and 2 November 2021,5.1 × 107 electrons and 3.1 × 106 positrons were obtained in the energy range[1.00-41.9]GeV,and daily electron flux and the positron flux for each of the three days were measured.There is no worldwide data on the 3-day flux of positrons.Cosmic rays must have passed through the solar system before being detected,and measuring the flux of cosmic rays on small time scales is crucial to the study of the relationship between solar modulation and charge and mass,providing valuable experimental data for a more comprehensive understanding of solar modulation.It is also an important step in the study of dark matter and the origin of cosmic rays.The electron flux in this thesis are based on ECAL acception measurements and are consistent with results published by the AMS Collaboration based on TRD acception(i.e.no cosmic rays are required to pass through ECAL),providing an independent check.The electron flux exhibits a completely different temporal variation from the proton flux.The positron flux shows different time scales,and the magnitude of the variation decreases with increasing energy.A comparison of the positron and electron flux shows that they have different time dependencies,with a time lag(Hysteresis)at energies below 8.48 GeV;when both flux change strongly,the time lag curves have a corresponding shortterm structure.Positrons and protons have the same charge and different masses.The positron and proton flux show similar temporal variations,with the positron and proton flux varying linearly overall from 2011 to 2018,with a departure from linearity starting in 2018.Precise data on cosmic ray positron,electron and proton fluxes across an 11-year cycle of solar activity offer the possibility of a complete understanding of the solar modulation of elementary particles. |
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