Conveners
AMS-02 experiment at the International Space Station: Tuesday block 1
- Mercedes Paniccia (University of Geneva (Switzerland))
- Manuela Vecchi ()
AMS-02 experiment at the International Space Station: Tuesday block 2
- Manuela Vecchi ()
- Mercedes Paniccia (University of Geneva (Switzerland))
Description
AMS-02 is a state-of-the-art particle physics detector operating onboard the International Space Station (ISS) since 2011. It studies the universe and its origin by searching for antimatter, and dark matter while performing precision measurements of cosmic-ray composition and flux. AMS is the unique magnetic spectrometer on the Space Station and will operate through the entire ISS lifetime up to 2030 and beyond.
Due to the exquisite data precision and the long-term mission AMS-02 has brought galactic cosmic-ray physics to an unprecedented precision level, discovering several unexpected phenomena that pose severe challenges to the conventional description of the sources and propagation of cosmic rays within our Galaxy.
In this session, we welcome contributions about AMS-02 measurements and the interpretation of these results.
In twelve years on the International Space Station, AMS has collected more than 230 billion cosmic rays up to energies of multi-TeV. The precision of the magnetic spectrometer enables us to present data to an accuracy of ~1%. Explicitly, the high energy data on elementary particles (electrons, positrons, antiprotons, and protons) requires new sources of explanation. The data on nuclei and...
We present high-statistics measurements of primary cosmic rays, including Proton, Helium, Carbon, Oxygen, Neon, Magnesium, Silicon, Sulfur, Iron, and Nickel, based on 11.5 years of AMS data. The data reveals, with high accuracy, that there are only three distinct classes of primary elements. Additionally, we provide a systematic comparison with the latest GALPROP cosmic ray model.
We present high-statistics measurements of the secondary cosmic rays Lithium, Beryllium, Boron, and Fluorine based on 11.5 years of AMS data. The unexpected rigidity dependence of the secondary cosmic ray fluxes and their ratios to the primary cosmic rays such as Li/C, Be/C, B/C, Li/O, Be/O, B/O, F/Si and P/Si are discussed. The systematic comparison with the latest GALPROP cosmic ray model is...
Cosmic ray acceleration inside compact star clusters has recently received much attention, mainly because of the detection of gamma ray emission from some of such astrophysical sources. Here we focus on the acceleration of nuclei at the wind termination shock and we investigate the role played by proton energy losses and spallation reactions of nuclei, especially downstream of the shock. We...
Recent measurements revealed the presence of several features in the cosmic ray spectrum. In particular, the proton and helium spectra exhibit a spectral hardening at ≈ 300 GV and a spectral steeping at ~ 15 TV, followed by the well known knee-like feature at ~ 3 PV. The spectra of heavier nuclei also harden at ~ 300 GV, while no claim can be currently done about the presence of the ~15 TV...
Electron capture (EC) decay relies on attachment and stripping cross-sections, that in turn, depend on the atomic number of the nucleus. We revisit the impact of EC decay in the context of the high-precision cosmic-ray fluxes measured by the AMS-02 experiment. We derive the solution of the steady-state fluxes in a 1D thin disk model including EC decay. We compare our results with relevant...
Precision measurements of the cosmic ray D flux are presented as function of rigidity from 1.9 to 21 GV, based on 21 million D nuclei. We observed that over the entire rigidity range D exhibit nearly identical time variations with p, ${}^{3}$He, and ${}^{4}$He fluxes. Above 4.5 GV, the D/⁴He flux ratio is time independent and its rigidity dependence is well described by a single power law ∝...
The precision measurement of daily proton fluxes with AMS during twelve years of operation in the rigidity interval from 1 to 100 GV is presented. The proton fluxes exhibit variations on multiple time scales. 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...
In the end of 2026, the AMS-02 experiment on the International Space Station will undergo a major upgrade of its apparatus: a double layer of microstrip silicon sensors, for a total area of ~ 7 m^2 and almost doubling the total area of the microstrip silicon tracker, called Layer 0 (L0) will be installed on top of the current flying apparatus.
In this talk we'll present briefly the design and...
In this talk, I will summarize the results presented during the Parallel session focused on the AMS-02 experiment on the International Space Station, together with their interpretation. In particular, I will discuss the latest flux measurements. The precision of AMS-02 results revealed unexpected phenomena that challenged conventional theoretical models. I will also give a brief overview of...
