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We report the unique properties of cosmic phosphorus (P), chlorine (Cl), argon (Ar), potassium (K), and calcium (Ca) fluxes in the GV to TV rigidity range collected by the Alpha Magnetic Spectrometer (AMS) on the International Space Station. With a total of one million events collected over 13.5 years, we observed that the rigidity dependencies of the five fluxes are well described by the sums of a primary cosmic ray component and a secondary cosmic ray component. The abundance ratios of all five elements to Si at the source are accurately determined independent of cosmic ray propagation. The source abundance of Ar and Ca (even- $Z$ elements) is larger than P, Cl, and K (odd- $Z$ elements). The secondary components of the P and the Cl fluxes are each $\sim 1/3$ of the F flux, and the secondary components of the Ar, K, and Ca fluxes are each $\sim 1/2$ of the F flux. The twenty elements measured by AMS, from He to Ca and Fe, can be categorized into four classes, two primary and two secondary, based on their rigidity dependence. 

We present the first measurement of cosmic-ray fluxes of ${}^6\mathrm{Li}$ and ${}^7\mathrm{Li}$ isotopes in the rigidity range from 1.9 to 25 GV. The measurements are based on $9.7\times {10}^5$ ${}^6\mathrm{Li}$ and $1.04\times {10}^6$ ${}^7\mathrm{Li}$ nuclei collected by the Alpha Magnetic Spectrometer on the International Space Station from May 2011 to October 2023. We observe that over the entire rigidity range the ${}^6\mathrm{Li}$ and ${}^7\mathrm{Li}$ fluxes exhibit nearly identical time variations and, above $\sim 4\mathrm{GV}$ , the time variations of ${}^6\mathrm{Li}$ , ${}^7\mathrm{Li}$ , He, Be, B, C, N, and O fluxes are identical. Above $\sim 7\mathrm{GV}$ , we find an identical rigidity dependence of the ${}^6\mathrm{Li}$ and ${}^7\mathrm{Li}$ fluxes. This shows that they are both produced by collisions of heavier cosmic-ray nuclei with the interstellar medium and, in particular, excludes the existence of a sizable primary component in the ${}^7\mathrm{Li}$ flux. Published by the American Physical Society2025 

We report the properties of precision time structures of cosmic nuclei He, Li, Be, B, C, N, and O fluxes over an 11-year solar cycle from May 2011 to November 2022 in the rigidity range from 1.92 to 60.3 GV. The nuclei fluxes show similar but not identical time variations with amplitudes decreasing with increasing rigidity. In particular, below 3.64 GV the Li, Be, and B fluxes, and below 2.15 GV the C, N, and O fluxes, are significantly less affected by solar modulation than the He flux. We observe that these differences in solar modulation are linearly correlated with the differences in the spectral indices of the cosmic nuclei fluxes. This shows, in a model-independent way, that solar modulation of galactic cosmic nuclei depends on their spectral shape. In addition, solar modulation differences due to nuclei velocity dependence on the mass-to-charge ratio ( $A/Z$ ) are not observed. Published by the American Physical Society2025 

We present results over an 11-year Solar cycle of cosmic antiprotons based on $1.1\times {10}^6$ events in the rigidity range from 1.00 to 41.9 GV. The $\overline{p}$ fluxes exhibit distinct properties. The magnitude of the $\overline{p}$ flux temporal variation is significantly smaller than those of $p$ , $e^{-}$ , and $e^{+}$ . A hysteresis between the $\overline{p}$ fluxes and the $p$ fluxes is observed, whereas the $\overline{p}$ and $e^{-}$ fluxes show a linear correlation. With a model-independent analysis, we found a universal relation between the shape of the rigidity spectrum and the magnitude of flux temporal variation over an 11-year Solar cycle for both positively and negatively charged particles. The simultaneous results on $\overline{p}$ and $p$ , $e^{-}$ , and $e^{+}$ provide unique information for understanding particle transport in the Solar System as a function of mass, charge, and spectral shape. 

Precision measurements by the Alpha Magnetic Spectrometer (AMS) on the International Space Station of the deuteron ( $D$ ) flux are presented. The measurements are based on $21\times {10}^6$ $D$ nuclei in the rigidity range from 1.9 to 21 GV collected from May 2011 to April 2021. We observe that over the entire rigidity range the $D$ flux exhibits nearly identical time variations with the $p$ , ${}^3\mathrm{He}$ , and ${}^4\mathrm{He}$ fluxes. Above 4.5 GV, the $D/{}^4\mathrm{He}$ flux ratio is time independent and its rigidity dependence is well described by a single power law $\propto R^{\mathrm{\Delta }}$ with ${\mathrm{\Delta }}_{D/{}^4\mathrm{He}}=-0.108\pm 0.005$ . This is in contrast with the ${}^3\mathrm{He}/{}^4\mathrm{He}$ flux ratio for which we find ${\mathrm{\Delta }}_{{}^3\mathrm{He}/{}^4\mathrm{He}}=-0.289\pm 0.003$ . Above $\sim 13\mathrm{GV}$ we find a nearly identical rigidity dependence of the $D$ and $p$ fluxes with a $D/p$ flux ratio of $0.027\pm 0.001$ . These unexpected observations indicate that cosmic deuterons have a sizable primarylike component. With a method independent of cosmic ray propagation, we obtain the primary component of the $D$ flux equal to $9.4\pm 0.5\%$ of the ${}^4\mathrm{He}$ flux and the secondary component of the $D$ flux equal to $58\pm 5\%$ of the ${}^3\mathrm{He}$ flux. Published by the American Physical Society2024