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1. chinaXiv:201711.02426 [pdf]

International time transfer of the Galileo initial service Based on the PPP method

Mingjun,Ouyang; Baoqi,Sun; Yulong,Ge ; Xuhai,Yang
分类: 物理学 >> 普通物理:统计和量子力学,量子信息等

The Galileo initial service is officially launched in December 15, 2016, by the European Commission (EC), owner of the European Galileo global navigation satellite system. This paper performs various experiments to test the Galileo initial service [Is not it better to use “Galileo initial service” instead of “Galileo system of initial service”?]using the Precise Point Position (PPP) method and selecting the time transfer links, and investigate its feasibility for the international time transfer. The time transfer links are constituted of the PTBB[What is the exact term?] site and MEGX sites connected with high-precision atomic clocks. We consider the results of the GPS PPP as reference, with a total of 138 days observation data, i.e. from December 15, 2016 to May 1, 2017. To investigate the reliability of the Galileo PPP based on the International UTC/TAI, we will design and carry out seven solutions with different options on the parameter selection, products utilization and the frequency selection. The experimental results show that the STD (Standard Deviation) ranges from 0.2ns to 0.5ns. This means, the PPP method reduces the time transfer [Right?]of the service of the international to nanosecond.

提交时间: 2017-11-19 点击量40, 下载量11

2. chinaXiv:201711.02420 [pdf]

Novel butynyl group incorporated pyrrolopyrimidine analogues as potent dipeptidyl peptidase IV inhibitors

Shaogao Zeng; Hui Xiea; Lili Zeng; Xin Lu; Xin Zhao; Guicheng Zhang; Zhengchao Tu; Hongjiang Xu; Ling Yang; Xiquan Zhang; Wenhui Hu
分类: 物理学 >> 普通物理:统计和量子力学,量子信息等

A new chemical class of potent DPP-IV inhibitors has been structurally derived from our recently disclosed pyrrolopyrimidine scaffold by replacing cyanobenzyl with butynyl group. Systematic variations and structure-activity relationship studies have been conducted on the starting hit 51 (IC50= 0.46 μM). Consequently, compound 78 (IC50= 1.55 nM) was identified to be a potent, selective, and orally available lead, worth further evaluations and optimizations.

提交时间: 2017-11-17 点击量13, 下载量6

3. chinaXiv:201711.02421 [pdf]

Highly potent depeptidyl peptidase IV inhibitors derived from Alogliptin with the pharmacophore hybridization and lead optimization

Hui Xie; Lili Zeng; Shaogao Zeng; Xin Lu; Xin Zhao; Guicheng ZhangZhengchao Tu; Hongjiang Xu; Ling Yang; Xiquan Zhang; Wenhui Hua
分类: 物理学 >> 普通物理:统计和量子力学,量子信息等

The structural superposition of DPP-IV complex with Alogliptin and Linagliptin displayed a similar binding mode. The butynyl of Linagliptin and cyanobenzyl of Alogliptin occupy the S1 pocket which therefore could be mutually switched. Thus a pharmacophore hybridization of Alogliptin was initiated and led to a novel DPP-IV inhibitor 61. Though it did not exhibit desired activity (IC50= 0.2 礛), the butynyl compound acts as a lead compound triggered a following structural optimization. A novel series of potent DPP-IV inhibitors represented by compound 77 (IC50= 0.36 nM) were obtained with a robust pharmacokinetic profile and better in vitro and in vivo efficacy than Alogliptin.

提交时间: 2017-11-17 点击量11, 下载量5

4. chinaXiv:201711.02257 [pdf]

Insight-HXMT observations of the first binary neutron star merger GW170817

TiPei Li; ShaoLin Xiong; ShuangNan Zhang; FangJun Lu; LiMing Song; XueLei Cao; Zhi Chang; Gang Chen; Li Chen; TianXiang Chen; Yong Chen; YiBao Chen; YuPeng Chen; Wei Cui; WeiWei Cui; JingKang Deng; YongWei Dong; YuanYuan Du; MinXue Fu; GuanHua Gao
分类: 物理学 >> 普通物理:统计和量子力学,量子信息等

Finding the electromagnetic (EM) counterpart of binary compact star merger, especially the binary neutron star (BNS) merger, is critically important for gravitational wave (GW) astronomy, osmology and fundamental physics. On Aug. 17, 2017, Advanced LIGO and Fermi/GBM independently triggered the first BNS merger, GW170817, and its high energy EM counterpart, GRB 170817A, respectively, resulting in a global observation campaign covering gamma-ray, X-ray, UV, optical, IR, radio as well as neutrinos. The High Energy X-ray telescope (HE) onboard Insight-HXMT (Hard X-ray Modulation Telescope) is the unique high-energy gamma-ray telescope that monitored the entire GW localization area and especially the optical counterpart (SSS17a/AT2017gfo) with very large collection area (~1000 cm2) and microsecond time resolution in 0.2-5 MeV. In addition, Insight-HXMT quickly implemented a Target of Opportunity (ToO) observation to scan the GW localization area for potential X-ray emission from the GW source. Although Insight-HXMT did not detect any significant high energy (0.2-5 MeV) radiation from GW170817, its observation helped to confirm the nexpected weak and soft nature of GRB 170817A. Meanwhile, Insight-HXMT/HE provides one of the most stringent constraints (~10-7 to 10-6 erg/cm2/s) for both GRB170817A and any other possible precursor or extended emissions in 0.2-5 MeV, which help us to better understand the properties of EM radiation from this BNS merger. Therefore the observation of Insight-HXMT constitutes an important chapter in the full context of multi-wavelength and multi-messenger observation of this historical GW event.

提交时间: 2017-11-10 点击量18, 下载量6

5. chinaXiv:201711.02258 [pdf]

The development of 222Rn detectors for JUNO prototype

Y.P.Zhang; J.C.Liu; C.Guo; Y.B.Huang; Z.Y.Yu; C.Xu; M.Y.Guan; C.G.Yang; P.Zhang
分类: 物理学 >> 普通物理:统计和量子力学,量子信息等

The radioactive noble gas 222Rn, which can be dissolved in water, is an important background source for JUNO. In this paper, based on the water system of JUNO prototype, two kinds of high sensitivity radon detectors have been proposed and validated. The sensitivity of Si-PIN Rn detector, which uses Si-PIN photodiode to detect the -214Po, is 4.2 mBq/m3 and the sensitivity of LS Rn detector, which uses liquid scintillator to detect the coincident signals of -214Bi and -214Po, is 34.4 mBq/m3. Both of the two kinds of Rn detector have the potential to be developped into an online Rn concentration monitoring equipment for JUNO veto detector.

提交时间: 2017-11-10 点击量14, 下载量8

6. chinaXiv:201711.02259 [pdf]

Probing Primordial Gravitational Waves: Ali CMB Polarization Telescope

Hong Li; Si-Yu Li; Yang Liu; Yong-Ping Li; Yifu Cai; Mingzhe Li; Gong-Bo Zhao; Cong-Zhan Liu; Zheng-Wei Li; He Xu; Di Wu; Yong-Jie Zhang; Zu-Hui Fan; Yong-Qiang Yao; Chao-Lin Kuo; Fang-Jun Lu; Xinmin Zhang
分类: 物理学 >> 普通物理:统计和量子力学,量子信息等

In this paper, we will give a general introduction to the project of Ali CMB Polarization Tele-scope (AliCPT), which is a Sino-US joint project led by the Institute of High Energy Physics (IHEP) and has involved many di erent institutes in China. It is the rst ground-based cosmic microwave background (CMB) polarization experiment in China and an integral part of China's Gravitational Waves Program. The main scienti c goal of AliCPT project is to probe the primor-dial gravitational waves (PGWs) originated from the very early Universe. The AliCPT project includes two stages. The rst stage referred to as AliCPT-1, is to build a telescope in the Ali region of Tibet with an altitude of 5,250 meters. Once completed, it will be the worldwide highest ground-based CMB observatory and open a new window for probing PGWs in northern hemisphere. AliCPT-1 telescope is designed to have about 7,000 TES detectors at 90GHz and 150GHz. The second stage is to have a more sensitive telescope (AliCPT-2) with the number of detectors more than 20,000. Our simulations show that AliCPT will improve the current constraint on the tensor-to-scalar ratio r by one order of magnitude with 3 years' observation. Besides the PGWs, the AliCPT will also enable a precise measurement on the CMB rotation angle and provide a precise test on the CPT symmetry. We show 3 years' observation will improve the current limit by two order of magnitude.

提交时间: 2017-11-10 点击量15, 下载量8

7. chinaXiv:201711.02260 [pdf]

Optimizing Higgs factories by modifying the recoil mass

Jiayin Gu; Ying-Ying Li
分类: 物理学 >> 普通物理:统计和量子力学,量子信息等

It is difficult to measure the WW-fusion Higgs production process (e+e− ! ¯ h) at a lepton collider with a center of mass energy of 240-250 GeV due to its small rate and the large background from the Higgsstrahlung process with an invisible Z(e+e− ! hZ, Z ! ¯ ). We construct a modified recoil mass variable, mp recoil,defined using only the 3-momentum of the reconstructed Higgs particle, and show that it can better separate the WW-fusion and Higgsstrahlung events than the original recoil mass variable mrecoil. Consequently, the mp recoil variable can be used to improve the overall precisions of the extracted Higgs couplings, in both the conventional framework and the effective-field-theory framework. We also explore the application of the mp recoil variable in the inclusive cross section measurements of the Higgsstrahlung process, while a quantitive analysis is left for future studies.

提交时间: 2017-11-10 点击量14, 下载量7

8. chinaXiv:201711.02261 [pdf]

Semiclassical spectrum for BMN string in Sch5 �S5

Hao Ouyang
分类: 物理学 >> 普通物理:统计和量子力学,量子信息等

We investigate the algebraic curve for string in Sch5 �S5. We compute the semiclassical spectrum for BMN string in Sch5 �S5 from the algebraic curve. We compare our results with the anomalous dimensions in sl(2) sector of the null dipole deformation of N = 4 super Yang-Mills theory.

提交时间: 2017-11-10 点击量13, 下载量7

9. chinaXiv:201711.02262 [pdf]

Status of Natural Supersymmetry from the GmSUGRA in Light of the current LHC Run-2 and LUX data

Waqas Ahmed; Xiao-Jun Bi; Tianjun Li; Jia Shu Niu; Shabbar Raza; Qian-Fei Xiang; Peng-Fei Yin
分类: 物理学 >> 普通物理:统计和量子力学,量子信息等

We study natural supersymmetry in the Generalized Minimal Supergravity (GmSUGRA).For the parameter space with low energy electroweak fine-tuning measures less than 50, we are left with only the Z-pole, Higgs-pole and Higgsino LSP scenarios for dark matter (DM). We perform the focused scans for such parameter space and find that it satisfies various phenomenological constraints and is compatible with the current direct detection bound on neutralino DM reported by the LUX experiment. Such parameter space also has solutions with correct DM relic density besides the solutions with DM relic density smaller or larger than 5 WMAP9 bounds. We present five benchmark points as examples. In these benchmark points, gluino and the first two generations of squarks are heavier than 2 TeV, stop ˜t1,2 are in the mass range [1, 2] TeV, while sleptons are lighter than 1 TeV. Some part of the parameter space can explain the muon anomalous magnetic moment within 3 as well. We also perform the collider study of such solutions by implementing and comparing with relevant studies done by the ATLAS and CMS Collaborations. We find that the points with Higgsino dominant ˜ 02/ ˜ ±1 mass upto 300 GeV are excluded in Z-pole scenario while for Higgs-pole scenario, the points with ˜ 02 mass up to 460 GeV are excluded. We also notice that the Higgsino LSP points in our present scans are beyond the reach of present LHC searches. Next, we show that for both the Z-pole and Higgs-pole scenarios, the points with electroweak fine-tuning measure around 20 do still survive.

提交时间: 2017-11-10 点击量12, 下载量6

10. chinaXiv:201711.02263 [pdf]

Learning from Higgs Physics at Future Higgs Factories

Jiayin Gu; Honglei Li; Zhen Liu; Shufang Su; Wei Su
分类: 物理学 >> 普通物理:统计和量子力学,量子信息等

Future Higgs factories can reach impressive precision on Higgs property measurements.In this paper, instead of conventional focus of Higgs precision in certain interaction bases, we explored its sensitivity to new physics models at the electron-positron colliders. In particular, we studied two categories of new physics models, Standard Model (SM) with a real scalar singlet extension, and Two Higgs Double Model (2HDM) as examples of weaklyinteracting models, Minimal Composite Higgs Model (MCHM) and three typical patterns of the more general operator counting for strong nteracting models as examples of strong dynamics. We performed a global t to various Higgs search channels to obtain the 95% C.L.constraints on the model parameter space. In the SM with a singlet xtension, we obtained the limits on the singlet-doublet mixing angle sin , as well as the more general Wilson coe cients of the induced higher dimensional operators. In the 2HDM, we analyzed tree level e ects in tan vs. cos(β-α) plane, as well as the one-loop contributions from the heavy Higgs bosons in the alignment limit to obtain the constraints on heavy Higgs masses for di erent types of 2HDM. In strong dynamics models, we obtained lower limits on the strong dynamics scale. In addition, once deviations of Higgs couplings are observed, they can be used to distinguish di erent models. We also compared the sensitivity of various future Higgs factories,namely Circular Electron Positron Collider (CEPC), Future Circular Collider (FCC)-ee and International Linear Collider (ILC).

提交时间: 2017-11-10 点击量15, 下载量9

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