Current Location:home > Browse

1. chinaXiv:201711.02307 [pdf]

Study of linearity of LYSO crystal for HERD calorimeter

Zheng Quan; Zhi-gang Wang; Ming Xu; Yong-wei Dong; Jun-jing Wang; Guang-peng An; Xin Liu; Tian-wei Bao; Li Zhang; Rui-jie Wang; Jun-guang Lv; Bo-bing Wu; Shuang-nan Zhang
Subjects: Physics >> General Physics: Statistical and Quantum Mechanics, Quantum Information, etc.

The High Energy cosmic Radiation Detection (HERD) facility is a space mission designed for detecting cosmic ray (CR) electrons, γ-rays up to tens of TeV and CR nuclei from proton to iron up to several PeV. The main instrument of HERD is a 3-D imaging calorimeter (CALO) composed of nearly ten thousand cubic LYSO crystals. A large dynamic range of single HERD CALO Cell (HCC) is necessary to achieve HERD’s PeV observation objectives, which means that the response of HCC should maintain a good linearity from minimum ionizing particle (MIP) calibration to PeV shower maximum. In order to study the linearity of HCC over such a large energy range, a beam test has been implemented at the E2 and E3 beam lines of BEPC. High intensity pulsed electron beam provided by E2 line are used for producing high energy density within HCC; π+/proton provided by E3 line are used for HCC calibration. The results show that no saturation e?ect occurs and the linearity of HCC is better than 10% from 30 MeV (1 MIP) to 1.1×103 TeV (energy density is 93 TeV/cm3), which can meet the requirement mentioned above.

submitted time 2017-11-10 Hits811Downloads356 Comment 0

2. chinaXiv:201703.00252 [pdf]


Gang Wang; Xiaolong Dong; Qingliu Bao; Di Zhu; Xingou Xu
Subjects: Geosciences >> Space Physics

For the spaceborne scanning pencil-beam scatterometer, the azimuth resolution is low that could not meet the demands. Based on the motion of platform and the scanning rules of the spaceborne scatterometer, this paper takes an unfocused SAR approach to improve the Azimuth Resolution.

submitted time 2017-03-10 Hits655Downloads361 Comment 0

3. chinaXiv:201609.00983 [pdf]

Analysis of the $\frac12^\pm $ pentaquark states in the diquark model with QCD sum rules

Zhi-Gang Wang; Tao Huang
Subjects: Physics >> Nuclear Physics

In this article, we present the scalar-diquark-scalar-diquark-antiquark type and scalar-diquark-axialvector-diquark-antiquark type pentaquark configurations in the diquark model, and study the masses and pole residues of the?JP=12±?hidden-charmed pentaquark states in details with the QCD sum rules by extending our previous work on the?JP=32??and?52+?hidden-charmed pentaquark states. We calculate the contributions of the vacuum condensates up to dimension-10 in the operator product expansion by constructing both the scalar-diquark-scalar-diquark-antiquark type and scalar-diquark-axialvector-diquark-antiquark type interpolating currents. The present predictions of the masses can be confronted to the LHCb experimental data in the future.

submitted time 2016-09-14 Hits361Downloads205 Comment 0

4. chinaXiv:201608.00190 [pdf]

Probing the Nature of the Electroweak Phase Transition from Particle Colliders to Gravitational Wave Detectors

Fa Peng Huang; Youping Wan; Dong-Gang Wang; Yi-Fu Cai; Xinmin Zhang
Subjects: Physics >> Nuclear Physics

In this letter, we explore the nature of the electroweak phase transition (EWPT) with both particle colliders and gravitational wave (GW) detection. With the observed Higgs mass, the shape of the Higgs potential is fully determined within the standard model (SM) of particle physics. However, it could be changed if there exists new physics beyond the SM. Working with the effective field theory, we show that a modified Higgs potential with a sextic term included can keep the observed 125 GeV Higgs mass but behave different when compared with the SM case. Furthermore, this potential can produce a strong first order phase transition (SFOPT) for the electroweak baryogenesis and interestingly predict new phenomena in the Higgs sector, which can be tested at colliders such as the Large Hadron Collider (LHC) and the planning Circular Electron Positron Collider (CEPC). We point out this SFOPT can lead to detectable signals for the GW interferometers , such as eLISA, DECIGO and BBO. Our present study on the EWPT bridges the particle physics at colliders with the astrophysics and cosmology in the early universe.

submitted time 2016-08-30 Hits396Downloads256 Comment 0

5. chinaXiv:201605.00412 [pdf]

Maize ZmVPP5 is a truncated Vacuole H<sup><nobr>+</nobr></sup>-PPase that confers hypersensitivity to salt stress

Xiaoliang Sun; Weiwei Qi; Yihong Yue; Huiling Ling; Gang Wang and Rentao Song
Subjects: Biology >> Botany >> Plant physiology

In plants, Vacuole H+-PPases (VPPs) are important proton pumps and encoded by multiple genes. In addition to full-length VPPs, several truncated forms are expressed, but their biological functions are unknown. In this study, we functionally characterized maize vacuole H+-PPase 5 (ZmVPP5), a truncated VPP in the maize genome. Although ZmVPP5 shares high sequence similarity with ZmVPP1, ZmVPP5 lacks the complete structure of the conserved proton transport and the inorganic pyrophosphatase-related domain. Phylogenetic analysis suggests that ZmVPP5 might be derived from an incomplete gene duplication event. ZmVPP5 is expressed in multiple tissues, and ZmVPP5 was detected in the plasma membrane, vacuole membrane and nuclei of maize cells. The overexpression of ZmVPP5 in yeast cells caused a hypersensitivity to salt stress. Transgenic maize lines with overexpressed ZmVPP5 also exhibited the salt hypersensitivity phenotype. A yeast two-hybrid analysis identified the ZmBag6-like protein as a putative ZmVPP5-interacting protein. The results of bimolecular luminescence complementation (BiLC) assay suggest an interaction between ZmBag6-like protein and ZmVPP5 in vivo. Overall, this study suggests that ZmVPP5 might act as a VPP antagonist and participate in the cellular response to salt stress. Our study of ZmVPP5 has expanded the understanding of the origin and functions of truncated forms of plant VPPs.

submitted time 2016-05-03 Hits374Downloads248 Comment 0

  [1 Pages/ 5 Totals]