Recent observations of the light component of the cosmic-ray spectrum have revealed unexpected features that motivate further and more precise measurements up to the highest energies. The Dark Matter Particle Explorer (DAMPE) is a satellite-based cosmic-ray experiment that is operational since December 2015, continuously collecting data on high-energy cosmic particles with very good statistics, energy resolution, and particle identification capabilities. In this work, the latest measurements of the energy spectrum of proton+helium in the energy range from 46 GeV to 316 TeV are presented. Among the most distinctive features of the spectrum, a spectral hardening at ∼600 GeV has been observed, along with a softening at ∼29 TeV measured with a 6.6σ significance. Moreover, by measuring the energy spectrum up to 316 TeV, a strong link is established between space-and ground-based experiments, also suggesting the presence of a second hardening at ∼150 TeV. * https://geant4.web.cern.ch/node/302 † https://web.ikp.kit.edu/rulrich/crmc.html

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The functional significance of BOLD signals in white matter (WM) remains unclear. The current study investigated whether 7T BOLD fMRI signal from visual WM tracts contains high fidelity retinotopic information and whether it correlates with the effective connectivity between visual areas. Population receptive field (pRF) analysis of the 7T retinotopy dataset from the Human Connectome Project revealed clear contralateral retinotopic representations from two visual WM bundles: optic radiation (OR) and vertical occipital fasciculus (VOF). The retinotopic organization of OR is consistent with post-mortem studies. The pRF size of WM voxels also increases with eccentricity. Based on the retinotopic maps of OR, we investigated whether BOLD signals in OR during visual stimulation are related to the resting-state effective connectivity between the lateral geniculate nucleus (LGN) and the primary visual cortex (V1). Results show that visually-evoked BOLD responses in OR correlate with the feedforward and feedback connectivity between the LGN and V1 during resting state. These findings demonstrate that WM BOLD signals contain high fidelity information such as visual field maps, and also predict the functional connectivity of brain areas.

In modern particle accelerators, the build-up of electron cloud is a main limiting factor for the achievement of high-quality beam. Among the techniques to mitigate it, coating the internal walls of the beam pipes with a thin film which has a low secondary electron yield (SEY) is considered to be one of the most effective means. From several earlier studies, it was found that diamond-like carbon (DLC) thin films are potential coatings. This paper is mainly about the research on secondary electron emission characteristics of DLC thin films. The secondary electron emission (SEE) tests were done at temperature of 298 K and vacuum pressure of 2 × 10–9 Torr. Here, we obtained the characteristics of the SEE from DLC film coatings with different thickness under ultrahigh-vacuum (UHV) conditions. The maximum secondary electron yield (SEY), δmax, of the DLC thin films under different primary electron doses were also obtained, respectively.

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