Recently the AMS-02 collaboration published detections of light cosmic-ray nuclei, including lithium, beryllium, boron, carbon, and oxygen. Combined with the released energy spectra of proton and helium, both primary and secondary spectra have a prominent hardening above ∼200 GV. In particular, the spectral variation of secondary cosmic rays is greater than the primary ones. One of the plausible interpretations for the above anomalies is the spatial-dependent diffusion model. It has successfully described various observational phenomena, e.g., hardening of primary nuclei, diffuse gamma-ray distribution and cosmic-ray anisotropy, etc. In this work, we apply the spatial-dependent propagation model to the latest observations, including both primary and secondary nuclei. Apart from the primary components, the spectra of secondary nuclei can be properly reproduced as well, especially the upturn above 200 GV. We also calculate the ratios of both secondary-to-primary and secondary-to-secondary. We find that except for the Be/B ratio, the computations of the spatial-dependent propagation model are in good agreement with the current data.

Growing evidence reveals universal hardening on various cosmic ray spectra, e.g., proton, positron, as well as antiproton fractions. Such universality may indicate they have a common origin. In this paper, we argue that these widespread excesses can be accounted for by a nearby supernova remnant surrounded by a giant molecular cloud. Secondary cosmic rays ($\mathrm{p}$, ${\mathrm{e}}^{+}$) are produced through the collisions between the primary cosmic-ray nuclei from this supernova remnant and the molecular gas. Different from the background, which is produced by the ensemble of a large number of sources in the Milky Way, the local injected spectrum can be harder. The time-dependent transport of particles would make the propagated spectrum even harder. Under this scenario, the anomalies of both primary ($\mathrm{p}$, ${\mathrm{e}}^{-}$) and secondary (${\mathrm{e}}^{+}$, $\overline{\mathrm{p}}/\mathrm{p}$) cosmic rays can be properly interpreted. We further show that the TeV to sub-PeV anisotropy of the proton is consistent with the observations if the local source is relatively young and lying at the anti-Galactic center direction.

We report the discovery of an ultrahigh-energy (UHE) gamma-ray source, LHAASO J2108+5157, by analyzing the LHAASO-KM2A data of 308.33 live days. A significant excess of gamma ray–induced showers is observed in both energy bands of 25−100 and >100 TeV with 9.5σ and 8.5σ, respectively. This source is not significantly favored as an extended source with an angular extension smaller than the point-spread function of KM2A. The measured energy spectrum from 20 to 200 TeV can be approximately described by a power-law function with an index of −2.83 ± 0.18_stat. A harder spectrum is demanded at lower energies considering the flux upper limit set by Fermi-LAT observations. The position of the gamma-ray emission is correlated with a giant molecular cloud, which favors a hadronic origin. No obvious counterparts have been found, and deeper multiwavelength observations will help to cast new light on this intriguing UHE source.