Measurement of helium flux and variability in low earth orbit with the Alpha Magnetic Spectrometer

Karagöz, Gülce
The Alpha Magnetic Spectrometer (AMS-02) is an unrivalled particle physics detec- tor with a large magnet whose aim is to search for anti-matter and dark matter by performing measurements on cosmic ray composition and flux. AMS-02 has been operating on the International Space Station (ISS) since its launch on the 16th May 2011, and is planned to operate along the lifetime of the ISS. AMS-02 has a unique design with a large acceptance and sensitive detection of cosmic rays, allowing one to better understand the acceleration and origin of cosmic rays. Helium nuclei are the second most abundant nuclei in the cosmic ray composition and since Helium has the smallest cross-section among the cosmic ray nuclei, it interacts the least with the interstellar medium, which means that the helium nuclei can travel from the furthest points of the galaxy. In this work, helium nuclei spectrum is studied in two parts. The first one is the time-independent helium flux, in which the flux is investigated in a large energy range up to 1.2TV. The second is the time-dependent helium flux, where the flux is investigated in a smaller energy scale in which our Sun dominates with its contribution.


Measurement of the proton flux and variability in low earth orbit with the alpha magnetic spectrometer
Konak, Çağlar; Demirköz, Melahat Bilge; Department of Physics (2019)
AMS-02 is a general purpose high energy particle detector, installed on the International Space Station on 19 May 2011 to detect dark matter and primordial anti-matter as well as measure the cosmic particles with unprecedented statistics. AMS-02 has a unique design including a powerful magnet, large acceptance with prolonged exposure time. Protons are the most abundant charged particles among other cosmic rays above a few 100s MeV. An understanding of precise behaviour of them accounts for the origin, acc...
Observation of Fine Time Structures in the Cosmic Proton and Helium Fluxes with the Alpha Magnetic Spectrometer on the International Space Station
Aguilar, M.; et. al. (American Physical Society (APS), 2018-7-31)
We present the precision measurement from May 2011 to May 2017 (79 Bartels rotations) of the proton fluxes at rigidities from 1 to 60 GV and the helium fluxes from 1.9 to 60 GV based on a total of 1 x 109 events collected with the Alpha Magnetic Spectrometer aboard the International Space Station. This measurement is in solar cycle 24, which has the solar maximum in April 2014. We observed that, below 40 GV, the proton flux and the helium flux show nearly identical fine structures in both time and relative ...
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Aad, G.; et. al. (Springer Science and Business Media LLC, 2011-09-01)
The dependence of the rate of proton-proton interactions on the centre-of-mass collision energy, root s, is of fundamental importance for both hadron collider physics and particle astrophysics. The dependence cannot yet be calculated from first principles; therefore, experimental measurements are needed. Here we present the first measurement of the inelastic proton-proton interaction cross-section at a centre-of-mass energy, root s, of 7 TeV using the ATLAS detector at the Large Hadron Collider. Events are ...
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Aad, G.; et. al. (Elsevier BV, 2011-06-27)
This Letter reports a measurement of the muon charge asymmetry from W bosons produced in proton-proton collisions at a centre-of-mass energy of 7 TeV with the ATLAS experiment at the LHC. The asymmetry is measured in the W -> mu nu decay mode as a function of the muon pseudorapidity using a data sample corresponding to a total integrated luminosity of 31 pb(-1). The results are compared to predictions based on next-to-leading order calculations with various parton distribution functions. This measurement pr...
Measurement of the transverse momentum distribution ofWbosons inppcollisions ats=7  TeVwith the ATLAS detector
Aad, G.; et. al. (American Physical Society (APS), 2012-1-18)
This paper describes a measurement of the W boson transverse momentum distribution using ATLAS pp collision data from the 2010 run of the LHC at ffiffi s p ¼ 7 TeV, corresponding to an integrated luminosity of about 31 pb 1. Events form both W ! e and W ! are used, and the transverse momentum of the W candidates is measured through the energy deposition in the calorimeter from the recoil of the W. The resulting distributions are unfolded to obtain the normalized differential cross sections as a function ...
Citation Formats
G. Karagöz, “Measurement of helium flux and variability in low earth orbit with the Alpha Magnetic Spectrometer,” M.S. - Master of Science, Middle East Technical University, 2022.