A Study of Cosmic Ray Secondaries Induced by the Mir Space Station Using AMS-01

The Alpha Magnetic Spectrometer (AMS-02) is a high energy particle physics experiment that will study cosmic rays in the $\sim 100 \mathrm{MeV}$ to $1 \mathrm{TeV}$ range and will be installed on the International Space Station (ISS) for at least 3 years. A first version of AMS-02, AMS-01, flew aboard the space shuttle \emph{Discovery} from June 2 to June 12, 1998, and collected $10^8$ cosmic ray triggers. Part of the \emph{Mir} space station was within the AMS-01 field of view during the four day \emph{Mir} docking phase of this flight. We have reconstructed an image of this part of the \emph{Mir} space station using secondary $\pi^-$ and $\mu^-$ emissions from primary cosmic rays interacting with \emph{Mir}. This is the first time this reconstruction was performed in AMS-01, and it is important for understanding potential backgrounds during the 3 year AMS-02 mission.Comment: To be submitted to NIM B Added material requested by referee. Minor stylistic and grammer change

Cosmic-ray positron fraction measurement from 1 to 30 GeV with AMS-01

A measurement of the cosmic ray positron fraction e+/(e+ + e-) in the energy range of 1-30 GeV is presented. The measurement is based on data taken by the AMS-01 experiment during its 10 day Space Shuttle flight in June 1998. A proton background suppression on the order of 10^6 is reached by identifying converted bremsstrahlung photons emitted from positrons

Precision Measurement of the Proton Flux in Primary Cosmic Rays from Rigidity 1 GV to 1.8 TV with the Alpha Magnetic Spectrometer on the International Space Station

A precise measurement of the proton flux in primary cosmic rays with rigidity (momentum/charge) from 1 GV to 1.8 TV is presented based on 300 million events. Knowledge of the rigidity dependence of the proton flux is important in understanding the origin, acceleration, and propagation of cosmic rays. We present the detailed variation with rigidity of the flux spectral index for the first time. The spectral index progressively hardens at high rigidities.</p

Periodicities in the Daily Proton Fluxes from 2011 to 2019 Measured by the Alpha Magnetic Spectrometer on the International Space Station from 1 to 100 GV

We present the precision measurement of the daily proton fluxes in cosmic rays from May 20, 2011 to October 29, 2019 (a total of 2824 days or 114 Bartels rotations) in the rigidity interval from 1 to 100 GV based on 5.5×109 protons collected with the Alpha Magnetic Spectrometer aboard the International Space Station. The proton fluxes exhibit variations on multiple timescales. From 2014 to 2018, we observed recurrent flux variations with a period of 27 days. Shorter periods of 9 days and 13.5 days are observed in 2016. The strength of all three periodicities changes with time and rigidity. The rigidity dependence of the 27-day periodicity is different from the rigidity dependences of 9-day and 13.5-day periods. Unexpectedly, the strength of 9-day and 13.5-day periodicities increases with increasing rigidities up to ∼10 GV and ∼20 GV, respectively. Then the strength of the periodicities decreases with increasing rigidity up to 100 GV.</p

Modulation Module for HelMod-4

The SDE integration with HelMod results in a quite expensive effort from the computational point of view since, to minimize the uncertainties, a huge amount of events should be integrated from Earth to the heliosphere boundary. Monte Carlo integration allows us to evaluate the normalized probability function (G) that a particle observed at Earth with rigidity R0 entered into the heliosphere with rigidity R. The convolution of the normalized probability function with the very local interstellar spectra result in the modulation of differential intensity for the time and solar distance where G was evaluated. In the present dataset, we provide the numerical output of HelMod-4 model (www.helmod.org) in the form of normalized probability histograms. The python script attached is able to convert GALPROP output (or plain text LIS file) to modulated spectrum for periods of selected experiments. This dataset was used as part of the publications in the references. For any information about the HelMod-4 Model, please refer to the official website. How to install and configure Install python (>3.0) packages astropy scypy >=0.17.0 numpy >=1.10 matplotlib Download the Python OfflineModule and the HelModArchive. The archive is provided in tgz format, thus it needs to be first unpacked with the command tar -xvzf .tgz. The archive structure: The HelModArchives.tgz contains several directories each one with the name of a space or balloon mission. Each folder should be considered as an HelMod Archive containing the following files: ExpList.list : List of nuclei and isotopes simulated (to not modify) ExpList_Plot.list: List of nuclei available in the archive, reference and plots properties (do not modify first and second columns, the others can be updated to modify the output plots) ParameterSimulated.list: list of folders in the form RawPar_HelMod4_XX, (at least one line should start with '+', if not, please add it to first line) ParameterSimulated_DB.list: list of folders in the form RawPar_HelMod4_XX, with description Version.txt : Version notes DataTXT : experimental energy and rigidity binning used for simulations RawPar_HelMod4_00 : HelMod simulations outputs How to use the module: The usage of the module requires three elements: An Helmod Archive unpacked in some known folder. E.g. let's =/home/test/Archive1 A LIS from galprop fits file OR plain text file format (hereafter called ). The label of the ion/dataset (hereafter called ) that are intended to be modulated. The list of available in each archive may be found in the file ExpList_Plot.list or using the command-line python3 HelMod_Module.py -a -l The basic command to get the modulated spectrum is: python3 HelMod_Module.py -a --LIS --SimName other available options: -h help description -t use this option to specify that is a two-column plain text file (see below). -p Choose a different set of parameters. The list of available parameter set names is available in the file ParameterSimulated_DB.list . --MakePlotCreate a Plot in png format. --SumAllIsotpes (can be used with GALPROP LIS inputs) evaluate the modulated spectra as the sum of the modulated isotopes spectra (note that without this option only the LIS of the isotope specified in is considered by the script). --PrintLIS Create a file with the LIS in the format of a two-column plain text file. --SimUnit force the Output Unit of the module: use Tkin to select Kinetic Energy per Nucleon [GeV/n], use Rigi to select Rigidity [GV]. If not specified, the output is chosen accordingly to the original format of the experimental dataset. -o Use a custom name for the output file. LIS in text format Users can provide a txt file for LIS with the following characteristics: The file must be a text file. The file must contain two columns only: one for kinetic energy per nucleon [GeV] the second for the LIS flux [ (m2 s sr GeV)-1]. The file may contain comments. Line starting with '#' character will be ignored

Nuclear and Non-Ionizing Energy-loss of Electrons with Low and Relativistic Energies in Materials and Space Environment

The treatment of the electron-nucleus interaction based on the Mott differential cross section was extended to account for effects due to screened Coulomb potentials, finite sizes and finite rest masses of nuclei for electrons above 200 keV and up to ultra high energies. This treatment allows one to determine both the total and differential cross sections, thus, subsequently to calculate the resulting nuclear and non-ionizing stopping powers. Above a few hundreds of MeV, neglecting the effect due to finite rest masses of recoil nuclei the stopping power and NIEL result to be largely underestimated; while, above a few tens of MeV the finite size of the nuclear target prevents a further large increase of stopping powers which approach almost constant values.The treatment of the electron-nucleus interaction based on the Mott differential cross section was extended to account for effects due to screened Coulomb potentials, finite sizes and finite rest masses of nuclei for electrons above 200 keV and up to ultra high energies. This treatment allows one to determine both the total and differential cross sections, thus, subsequently to calculate the resulting nuclear and non-ionizing stopping powers. Above a few hundreds of MeV, neglecting the effect due to finite rest masses of recoil nuclei the stopping power and NIEL result to be largely underestimated; while, above a few tens of MeV the finite size of the nuclear target prevents a further large increase of stopping powers which approach almost constant values

Deciphering the Local Interstellar Spectra of Primary Cosmic-Ray Species with HelMod

Local interstellar spectra (LIS) of primary cosmic ray (CR) nuclei, such as helium, oxygen, and mostly primary carbon are derived for the rigidity range from 10 MV to 3c200 TV using the most recent experimental results combined with the state-of-the-art models for CR propagation in the Galaxy and in the heliosphere. Two propagation packages, GALPROP and HelMod, are combined into a single framework that is used to reproduce direct measurements of CR species at different modulation levels, and at both polarities of the solar magnetic field. The developed iterative maximum-likelihood method uses GALPROP-predicted LIS as input to HelMod, which provides the modulated spectra for specific time periods of the selected experiments for model-data comparison. The interstellar and heliospheric propagation parameters derived in this study are consistent with our prior analyses using the same methodology for propagation of CR protons, helium, antiprotons, and electrons. The resulting LIS accommodate a variety of measurements made in the local interstellar space (Voyager 1) and deep inside the heliosphere at low (ACE/CRIS, HEAO-3) and high energies (PAMELA, AMS-02)

HelMod in the Works: From Direct Observations to the Local Interstellar Spectrum of Cosmic-Ray Electrons

The local interstellar spectrum (LIS) of cosmic-ray (CR) electrons for the energy range 1 MeV to 1 TeV is derived using the most recent experimental results combined with the state-of-the-art models for CR propagation in the Galaxy and in the heliosphere. Two propagation packages, GALPROP and HelMod, are combined to provide a single framework that is run to reproduce direct measurements of CR species at different modulation levels, and at both polarities of the solar magnetic field. An iterative maximum-likelihood method is developed that uses GALPROP-predicted LIS as input to HelMod, which provides the modulated spectra for specific time periods of the selected experiments for model-data comparison. The optimized HelMod parameters are then used to adjust GALPROP parameters to predict a refined LIS with the procedure repeated subject to a convergence criterion. The parameter optimization uses an extensive data set of proton spectra from 1997 to 2015. The proposed CR electron LIS accommodates both the low-energy interstellar spectra measured by Voyager 1 as well as the high-energy observations by PAMELA and AMS-02 that are made deep in the heliosphere; it also accounts for Ulysses counting rate features measured out of the ecliptic plane. The interstellar and heliospheric propagation parameters derived in this study agree well with our earlier results for CR protons, helium nuclei, and anti-protons propagation and LIS obtained in the same framework

Solution of Heliospheric Propagation: Unveiling the Local Interstellar Spectra of Cosmic-ray Species

Local interstellar spectra (LIS) for protons, helium, and antiprotons are built using the most recent experimental results combined with state-of-the-art models for propagation in the Galaxy and heliosphere. Two propagation packages, GALPROP and HelMod, are combined to provide a single framework that is run to reproduce direct measurements of cosmic-ray (CR) species at different modulation levels and at both polarities of the solar magnetic field. To do so in a self-consistent way, an iterative procedure was developed, where the GALPROP LIS output is fed into HelMod, providing modulated spectra for specific time periods of selected experiments to compare with the data; the HelMod parameter optimization is performed at this stage and looped back to adjust the LIS using the new GALPROP run. The parameters were tuned with the maximum likelihood procedure using an extensive data set of proton spectra from 1997 to 2015. The proposed LIS accommodate both the low-energy interstellar CR spectra measured by Voyager 1 and the high-energy observations by BESS, Pamela, AMS-01, and AMS-02 made from the balloons and near-Earth payloads; it also accounts for Ulysses counting rate features measured out of the ecliptic plane. The found solution is in a good agreement with proton, helium, and antiproton data by AMS-02, BESS, and PAMELA in the whole energy range