Properties of Heavy Cosmic Nuclei Phosphorus, Chlorine, Argon, Potassium, and Calcium: Results from the Alpha Magnetic Spectrometer
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 ∼1/3 of the F flux, and the secondary components of the Ar, K, and Ca fluxes are each ∼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.
Table-SI
Download the P flux tableThe P flux $\Phi_\mathrm{P}$ as a function of rigidity at the top of AMS in units of $\mathrm{[m^2\cdot sr \cdot s \cdot GV]^{-1}}$ including errors due to statistics (stat.); contributions to the systematic error from the trigger, background, and acceptance (acc.); the rigidity resolution function and unfolding (unf.); the absolute rigidity scale (scale); and the total systematic error (syst.). The contributions of individual sources to the systematic error are added in quadrature to arrive at the total systematic error.
Table-SII
Download the Cl flux tableThe Cl flux $\Phi_\mathrm{Cl}$ as a function of rigidity at the top of AMS in units of $\mathrm{[m^2\cdot sr \cdot s \cdot GV]^{-1}}$ including errors due to statistics (stat.); contributions to the systematic error from the trigger, background, and acceptance (acc.); the rigidity resolution function and unfolding (unf.); the absolute rigidity scale (scale); and the total systematic error (syst.). The contributions of individual sources to the systematic error are added in quadrature to arrive at the total systematic error.
Table-SIII
Download the Ar flux tableThe Ar flux $\Phi_\mathrm{Ar}$ as a function of rigidity at the top of AMS in units of $\mathrm{[m^2\cdot sr \cdot s \cdot GV]^{-1}}$ including errors due to statistics (stat.); contributions to the systematic error from the trigger, background, and acceptance (acc.); the rigidity resolution function and unfolding (unf.); the absolute rigidity scale (scale); and the total systematic error (syst.). The contributions of individual sources to the systematic error are added in quadrature to arrive at the total systematic error.
Table-SIV
Download the K flux tableThe K flux $\Phi_\mathrm{K}$ as a function of rigidity at the top of AMS in units of $\mathrm{[m^2\cdot sr \cdot s \cdot GV]^{-1}}$ including errors due to statistics (stat.); contributions to the systematic error from the trigger, background, and acceptance (acc.); the rigidity resolution function and unfolding (unf.); the absolute rigidity scale (scale); and the total systematic error (syst.). The contributions of individual sources to the systematic error are added in quadrature to arrive at the total systematic error.
Table-SV
Download the Ca flux tableThe Ca flux $\Phi_\mathrm{Ca}$ as a function of rigidity at the top of AMS in units of $\mathrm{[m^2\cdot sr \cdot s \cdot GV]^{-1}}$ including errors due to statistics (stat.); contributions to the systematic error from the trigger, background, and acceptance (acc.); the rigidity resolution function and unfolding (unf.); the absolute rigidity scale (scale); and the total systematic error (syst.). The contributions of individual sources to the systematic error are added in quadrature to arrive at the total systematic error.
Table-SVI
Download the Si flux tableThe Si flux $\Phi_\mathrm{Si}$ as a function of rigidity at the top of AMS in units of $\mathrm{[m^2\cdot sr \cdot s \cdot GV]^{-1}}$ including errors due to statistics (stat.); contributions to the systematic error from the trigger, background, and acceptance (acc.); the rigidity resolution function and unfolding (unf.); the absolute rigidity scale (scale); and the total systematic error (syst.). The contributions of individual sources to the systematic error are added in quadrature to arrive at the total systematic error.
Table-SVII
Download the F flux tableThe F flux $\Phi_\mathrm{F}$ as a function of rigidity at the top of AMS in units of $\mathrm{[m^2\cdot sr \cdot s \cdot GV]^{-1}}$ including errors due to statistics (stat.); contributions to the systematic error from the trigger, background, and acceptance (acc.); the rigidity resolution function and unfolding (unf.); the absolute rigidity scale (scale); and the total systematic error (syst.). The contributions of individual sources to the systematic error are added in quadrature to arrive at the total systematic error.
Table-SVIII
Download the S flux tableThe S flux $\Phi_\mathrm{S}$ as a function of rigidity at the top of AMS in units of $\mathrm{[m^2\cdot sr \cdot s \cdot GV]^{-1}}$ including errors due to statistics (stat.); contributions to the systematic error from the trigger, background, and acceptance (acc.); the rigidity resolution function and unfolding (unf.); the absolute rigidity scale (scale); and the total systematic error (syst.). The contributions of individual sources to the systematic error are added in quadrature to arrive at the total systematic error.
The phosphorus to sulfur flux ratio $\Phi_\mathrm{P}/\Phi_\mathrm{S}$ as a function of rigidity including errors due to statistics (stat.); contributions to the systematic error from the trigger, acceptance, and background (acc.); the rigidity resolution function and unfolding (unf.); the absolute rigidity scale (scale); and the total systematic error (syst.). The statistical errors are the sum in quadrature of the ratios of phosphorus and sulfur flux statistical errors to the corresponding flux values, multiplied by $\Phi_\mathrm{P}/\Phi_\mathrm{S}$. The systematic errors from the background subtraction, the trigger, and the event reconstruction and selection are likewise added in quadrature. The correlations in the systematic errors from the uncertainty in nuclear interaction cross sections, the unfolding and the absolute rigidity scale between the phosphorus and sulfur fluxes have been taken into account in calculating the corresponding systematic errors of $\Phi_\mathrm{P}/\Phi_\mathrm{S}$. The contribution of individual sources to the systematic error are added in quadrature to arrive at the total systematic uncertainty.
Table-SX
Download the argon flux ratio tableThe chlorine to argon flux ratio $\Phi_\mathrm{Cl}/\Phi_\mathrm{Ar}$ as a function of rigidity including errors due to statistics (stat.); contributions to the systematic error from the trigger, acceptance, and background (acc.); the rigidity resolution function and unfolding (unf.); the absolute rigidity scale (scale); and the total systematic error (syst.). The statistical errors are the sum in quadrature of the ratios of chlorine and argon flux statistical errors to the corresponding flux values, multiplied by $\Phi_\mathrm{Cl}/\Phi_\mathrm{Ar}$. The systematic errors from the background subtraction, the trigger, and the event reconstruction and selection are likewise added in quadrature. The correlations in the systematic errors from the uncertainty in nuclear interaction cross sections, the unfolding and the absolute rigidity scale between the chlorine and argon fluxes have been taken into account in calculating the corresponding systematic errors of $\Phi_\mathrm{Cl}/\Phi_\mathrm{Ar}$. The contribution of individual sources to the systematic error are added in quadrature to arrive at the total systematic uncertainty.
The potassium to calcium flux ratio $\Phi_\mathrm{K}/\Phi_\mathrm{Ca}$ as a function of rigidity including errors due to statistics (stat.); contributions to the systematic error from the trigger, acceptance, and background (acc.); the rigidity resolution function and unfolding (unf.); the absolute rigidity scale (scale); and the total systematic error (syst.). The statistical errors are the sum in quadrature of the ratios of potassium and calcium flux statistical errors to the corresponding flux values, multiplied by $\Phi_\mathrm{K}/\Phi_\mathrm{Ca}$. The systematic errors from the background subtraction, the trigger, and the event reconstruction and selection are likewise added in quadrature. The correlations in the systematic errors from the uncertainty in nuclear interaction cross sections, the unfolding and the absolute rigidity scale between the potassium and calcium fluxes have been taken into account in calculating the corresponding systematic errors of $\Phi_\mathrm{K}/\Phi_\mathrm{Ca}$. The contribution of individual sources to the systematic error are added in quadrature to arrive at the total systematic uncertainty.
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