分类: 地球科学 >> 地球科学其他学科 提交时间: 2024-08-13
摘要: The traditional uniformity coefficient Cu cannot reflect the uniformity of gap-graded granular mixtures. This paper proposes a new index CmuCum to quantify the uniformity of granular mixtures based on the study on their small-strain stiffness G0. The samples of granular mixtures with different fines content (FC) and particle size ratio (PSR) are prepared. The G0 values are determined by quasistatic drained triaxial tests on these samples. The CmuCum values are calculated from the obtained G0 values and can be expressed as a function of FC and PSR. The rationality of the proposed CmuCum is verified. The CmuCum can be used to predict the G0 of granular mixtures when the mechanical coordination number (CNm), shear modulus of particles (Gp), confining stress (σ0) and CmuCum are given.
分类: 物理学 >> 核物理学 提交时间: 2024-01-18
摘要: The elliptic azimuthal anisotropy coefficient ($v_{2}$) of the identified particles at midrapidity ($ eta <0.8$) was investigated in p--Pb collisions at $ sqrt{s_ mathrm{NN}}=$ 5.02 TeV using a multi-phase transport model (AMPT). The calculations of differential $v_{2}$ based on the advanced flow extraction method of light flavor hadrons (pions, kaons, protons, and $ Lambda$) in small collision systems were extended to a wider transverse momentum ($p_{ mathrm{T}}$) range of up to 8 GeV/$c$ for the first time. The string- melting version of the AMPT model provides a good description of the measured $p_{ mathrm{T}}$-differential $v_{2}$ of the mesons but exhibits a slight deviation from the baryon $v_{2}$. In addition, we observed the features of mass ordering at low $p_{ mathrm{T}}$ and the approximate number of constituent quarks (NCQ) scaled at intermediate $p_{ mathrm{T}}$. Moreover, we demonstrate that hadronic rescattering does not have a significant impact on $v_{2}$ in p--Pb collisions for different centrality selections, whereas partonic scattering dominates in generating the elliptic anisotropy of the final particles. This study provides further insight into the origin of collective-like behavior in small collision systems and has referential value for future measurements of azimuthal anisotropy.
分类: 物理学 >> 核物理学 提交时间: 2016-09-02
摘要: The discovery of the neutrino mixing angle θ13 opens new opportunities for the discovery of the leptonic CP violation for high intensity neutrino beams. MOMENT a future neutrino facility with a high-power proton beam of 15 MW from a continuous-wave linac is focused on that discovery. The high power of the proton beam causes extreme radiation conditions for the facility and especially for the target station where the pion capture system of five superconducting solenoids is located. In this paper initial studies are performed for the effects of the radiation on the solenoid structure and the area surrounding it. A concept cooling system is also proposed.