作者机构：
[刘美华; 田茂; 陈小莉] Electronic Information School, Wuhan University, Wuhan, 430072, China;[张新晨] School of Physical Science and Technology, Central China Normal University, Wuhan, 430079, China
通讯机构：
School of Physical Science and Technology, Central China Normal University, Wuhan, China
通讯机构：
[Tang, Yiwen] C;[Yuan, N; Li, MY] W;Wuhan Univ, Sch Phys & Technol, Key Lab Artificial Micro Nano Struct, Minist Educ, Wuhan 430072, Peoples R China.;Cent China Normal Univ, Coll Phys Sci & Technol, Wuhan 430079, Hubei, Peoples R China.
关键词：
Au nanoparticles;Dye-sensitized solar cells;Gradient-ascent architecture scattering;Localized surface plasmon resonance;SiO2@[email protected]2 microspheres
摘要：
Highly homogeneous, well dispersed SiO2@Au@TiO2(SAT) microspheres decorated with Au nanoparticles (AuNPs) were prepared and incorporated into the photoanode with an optimized concentration gradient-ascent. The effects of SAT microspheres and the gradient-ascent architecture on the light absorption and the photoelectric conversion efficiency (PCE) of the dye-sensitized solar cells (DSSCs) were investigated. Studies indicate that the introduction of SAT microspheres and the gradient-ascent architecture in the photoanode significantly enhance the light scattering and harvesting capability of the photoanode. The DSSC with the optimized SAT gradient-ascent photoanode has the maximum short circuit current density (J(sc)) of 17.7 mA cm(-2) and PCE of 7.75%, remarkably higher than those of the conventional DSSC by 23.7% and 28.0%, respectively. This significantly enhancement of the performance of the DSSC can be attributed to the excellent light reflection/scattering of SAT, the localized surface plasma resonance (LSPR) effect of AuNPs within the microspheres, and the gradient-ascent architecture of SAT microspheres inside the photoanode. This study demonstrates that the tri-synergies of the scattering of SAT microspheres, the LSPR of AuNPs and the gradient-ascent architecture can effectively improve the PCE of DSSC. (C) 2019 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.
作者机构：
[Yu, Yun-Wei] Cent China Normal Univ, Inst Astrophys, Wuhan 430079, Hubei, Peoples R China.;Cent China Normal Univ, Key Lab Quark & Lepton Phys, Wuhan 430079, Hubei, Peoples R China.
通讯机构：
[Yu, Yun-Wei] C;Cent China Normal Univ, Inst Astrophys, Wuhan 430079, Hubei, Peoples R China.
关键词：
gamma ray bursts: general;gravitational waves
摘要：
During the in-spiral stage of a compact binary, a wind bubble could be blown into the interstellar meditun, if electromagnetic radiation due to the binary orbital motion is strong enough. Therefore, short-duration gamma-ray bursts (SGRBs) due to double neutron star mergers would in principle happen in a wind bubble environment, which can influence the propagation of the SGRB jet and consequent afterglow emission. By calculating the dynamics and synchrotron radiation of the jet-driven external shock, we reveal that an abrupt jump could appear in the afterglow light curves of SGRBs and the observational time of the jump is dependent on the viewing angle. This light curve jump provides an observational signature to constrain the radius of the wind bubble and thus the power of the electromagnetic radiation of the binary, by combining with gravitational wave detection.
作者机构：
[Yan, Han] Cent China Normal Univ, Inst Particle Phys, Wuhan 430079, Hubei, Peoples R China.;Cent China Normal Univ, Key Lab Quark & Lepton Phys MOE, Wuhan 430079, Hubei, Peoples R China.
通讯机构：
[Yan, Han] C;Cent China Normal Univ, Inst Particle Phys, Wuhan 430079, Hubei, Peoples R China.
关键词：
new physics;leptoquark;B decay
摘要：
During the past few years, signs of lepton flavor universality (LFU) violation have been observed in b -> c tau(v) over bar and b -> sl(+)l(-) transitions. Recently, the D* and tau polarization fractions P-L(D)* and P-L(tau) in B -> D*tau(v) over bar decay were likewise measured by the Belle collaboration. Motivated by these intriguing results, we revisit the R-D(*) and R-K(*) anomalies in a scalar leptoquark (LQ) model, where two scalar LQs, one of which is a S U(2)(L) singlet and the other a S U(2)(L) triplet, are introduced simultaneously. We consider five b -> c tau(v) over bar mediated decays, B -> D-(*())tau(v) over bar, B-C -> eta(C)tau(v) over bar , B-C -> J/psi tau(v) over bar and Lambda(b) -> Lambda(C)tau(v) over bar, and focus on the LQ effects on the q(2) distributions of the branching fractions, LFU ratios, and various angular observables in these decays. Under the combined constraints of the available data on R-D(*), R-J/psi, P-L(tau)(D*) and P-L(D)* , we perform scans for the LQ couplings and make predictions for a number of observables in these decays. Numerically it is found that both the differential branching fractions and LFU ratios are largely enhanced by the LQ effects, with the latter expected to provide testable signatures at the SuperKEKB and High-Luminosity LHC experiments.
通讯机构：
Xinjiang Astronomical Observatory, Chinese Academy of Sciences, Urumqi, China
关键词：
天文终端;快速射电暴;多波束接收机;信号分析
摘要：
快速射电暴(Fast Radio Burst, FRB)是一种偶发的、瞬时射电暴,为了探测到更多的样本进行研究,本文基于多波束接收机开发了一套实时搜寻终端,该系统包括信号采集与处理、单波束信号处理、多波束信号合成与分析、探测结果存储与发布等单元,可以对多路波束信号进行同时采集和分析,利用多波束的信号参考效应消除干扰,提高探测准确率.在某射电望远镜上进行了观测实验,通过捕捉脉冲星的单脉冲信号检验了FRB信号的探测功能,结果表明该终端可实现准确、实时的FRB探测.
作者机构：
[Katsuragawa, Taishi] Cent China Normal Univ, Inst Astrophys, Wuhan 430079, Hubei, Peoples R China.;[Matsuzaki, Shinya] Jilin Univ, Ctr Theoret Phys, Changchun 130012, Jilin, Peoples R China.;[Matsuzaki, Shinya] Jilin Univ, Coll Phys, Changchun 130012, Jilin, Peoples R China.;[Senaha, Eibun] IBS, Ctr Theoret Phys Universe, Daejeon 34051, Peoples R China.
通讯机构：
[Katsuragawa, Taishi] C;Cent China Normal Univ, Inst Astrophys, Wuhan 430079, Hubei, Peoples R China.
关键词：
modified gravity;beyond standard model;thermal field theory
摘要：
It is widely believed that the screening mechanism is an essential feature for the modified gravity theory. Although this mechanism has been examined thoroughly in the past decade, their analyses are based on a conventional fluid prescription for the matter-sector configuration. In this paper, we demonstrate a new formulation of the chameleon mechanism in F(R) gravity theory, to shed light on quantum-field theoretical effects on the chameleon mechanism as well as the related scalaron physics, induced by the matter sector. We show a possibility that the chameleon mechanism is absent in the early Universe based on a scale-invariant-extended scenario beyond the standard model of particle physics, in which a realistic electroweak phase transition, yielding the right amount of baryon asymmetry of Universe today, simultaneously breaks the scale invariance in the early Universe. We also briefly discuss the oscillation of the scalaron field and indirect generation of non-tensorial gravitational waves induced by the electroweak phase transition.
摘要：
A digital correlator is a crucial element in a modern radio telescope. In this paper, we describe a scalable design for the correlator system of the Tianlai pathfinder array, which is an experiment dedicated to testing key technologies for conducting a 21 cm intensity mapping survey. The correlator implements the FX design, which firstly performs a fast Fourier transform (FFT) including polyphase filter bank (PFB) computation using a Collaboration for Astronomy Signal Processing and Electronics Research (CASPER) Reconfigurable Open Architecture Computing Hardware-2 (ROACH2) board, then computes cross-correlations by employing Graphics Processing Units (GPUs). The design has been tested both in laboratory and in actual observation.
摘要：
A quark coalescence model, based on semi-relativistic molecular dynamics with color interactions among quarks, is presented and applied to pp collisions. A phenomenological potential with two tunable parameters is introduced to describe the color interactions between quarks and antiquarks. The interactions drive the process of hadronization that finally results in different color neutral clusters, which can be identified as hadrons based on some criteria. A Monte Carlo generator PYTHIA is used to generate quarks in the initial state of hadronization, and different values of tunable parameters are used to study the final state distributions and correlations. Baryon-to-meson ratio, transverse momentum spectra, pseudorapidity distributions and forward-backward multiplicity correlations of hadrons produced in the hadronization process, obtained from this model with different parameters, are compared with those from PYTHIA.
