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Test of the Cosmic Transparency with the Baryon Acoustic Oscillation and Type Ia Supernova Data

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Chinese physics Letters 2016年第5期33卷 149-151页

作者：李合昆吴普训余洪伟 center of nonlinear science and department of physics Ningbo University

We use the latest baryon acoustic oscillation and Union 2.1 type Ia supernova data to test the cosmic opacity between different redshift regions without assuming any cosmological models. It is found that the universe may be opaque between the redshift regions 0.35 0.44, 0.44 0.57 and 0.6-0.73 since the best fit values of cosmic opacity in these regions are positive, while a transparent universe is favored in the redshift region 0.57-0.63. However, in general, a transparent universe is still consistent with observations at the lo confidence level.

关键词： of in Test of the Cosmic Transparency with the Baryon Acoustic Oscillation and Type Ia Supernova Data with that is

Inflationary dynamics in the braneworld scenarios

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Chinese physics B 2013年第5期22卷 669-673页

作者：张开源吴普训余洪伟 center of nonlinear science and department of physics Ningbo University

We analyze the attractor behaviour of the inflation field in braneworld scenarios using the Hamilton-Jacobi formalism, where the Friedmann equation has the form of H2 = ρ + ε(2ρ0ρ)1/2or H2 = ρ + ερ2/2σ , with ε = ±1. We find that in all models the linear homogeneous perturbation can decay exponentially as the scalar field rolls down its potential. However, in the case of a -ρ2 correction to the standard cosmology with ρ 1. Our results show that the perturbation decays more quickly in models with positive-energy correction than in the standard cosmology, which is opposite to the case of negative-energy correction. Thus, the positive-energy modification rather than the negative one can assist the inflation and widen the range of initial conditions.

关键词： inflation braneworld attractor

Localization of Nonlocal Symmetries and Symmetry Reductions of Burgers Equation

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Communications in Theoretical physics 2017年第5期67卷 467-472页

作者：吴剑文楼森岳俞军 center for nonlinear science and department of physics Ningbo University Institute of nonlinear science Shaoxing University

The nonlocal symmetries of the Burgers equation are explicitly given by the truncated Painlevé *** auto-B?cklund transformation and group invariant solutions are obtained via the localization procedure for the nonlocal residual symmetries. Furthermore, the interaction solutions of the solition-Kummer waves and the solition-Airy waves are obtained.

关键词： integrable systems Burgers equation nonlocal symmetries interactions among different waves

Novel Localized Excitations of nonlinear Coupled Scalar Fields

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Communications in Theoretical physics 2008年第6期49卷 1365-1372页

作者： LI Jin-Hua WU Huang-Jiao department of physics and center of nonlinear science Ningbo University Ningbo 315211 China

Some extended solution mapping relations of the nonlinear coupled scalar field and the well-known φ^4 model are presented. Simultaneously, inspired by the new solutions of the famous φ^4 model recently proposed by Jia, Huang and Lou, five kinds of new localized excitations of the nonlinear coupled scaiar field （NCSF） system are obtained.

关键词： nonlinear coupled scalar field solitary wave structure mapping and deformation approach

Extended symmetry transformation of (3+1)-dimensional generalized nonlinear Schrdinger equation with variable coefficients

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Chinese physics B 2013年第1期22卷 77-83页

作者：荆建春李彪 nonlinear science center and department of Mathematics Ningbo University

In this paper, the extended symmetry transformation of （3＋1）-dimensional （3D） generalized nonlinear Schrodinger （NLS） equations with variable coefficients is investigated by using the extended symmetry approach and symbolic computation. Then based on the extended symmetry, some 3D variable coefficient NLS equations are reduced to other variable coefficient NLS equations or the constant coefficient 3D NLS equation. By using these symmetry transformations, abundant exact solutions of some 3D NLS equations with distributed dispersion, nonlinearity, and gain or loss are obtained from the constant coefficient 3D NLS equation.

关键词： (3+1)-dimensional nonlinear Schrodinger equation extended symmetry exact solution symbolic computation

Dynamics of solitons of the generalized(3+1)-dimensional nonlinear Schr(o|¨)dinger equation with distributed coefficients

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Chinese physics B 2011年第11期20卷 339-345页

作者：刘晓蓓李彪 nonlinear science center and department of Mathematics Ningbo University

We present three families of soliton solutions to the generalized （3＋l）-dimensional nonlinear Schrodinger equation with distributed coefficients. We investigate the dynamics of these solitons in nonlinear optics with some selected parameters. Different shapes of bright solitons, a train of bright solitons and dark solitons are observed. The obtained results may raise the possibilities of relevant experiments and potential applications.

关键词： (3+l)-dimensional nonlinear Schodinger Equation optical soliton soliton propagation

Exact analytical solutions of three-dimensional Gross-Pitaevskii equation with time-space modulation

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Chinese physics B 2011年第5期20卷 122-129页

作者：胡晓李彪 nonlinear science center and department of Mathematics Ningbo University

By the generalized sub-equation expansion method and symbolic computation, this paper investigates the （3＋1）dimensional Gross-Pitaevskii equation with time-and space-dependent potential, time-dependent nonlinearity, and gain or loss. As a result, rich exact analytical solutions are obtained, which include bright and dark solitons, Jacobi elliptic function solutions and Weierstrass elliptic function solutions. With computer simulation, the main evolution features of some of these solutions are shown by some figures. nonlinear dynamics of a soliton pulse is also investigated under the different regimes of soliton management.

关键词： Gross-Pitaevskii equation soliton solutions Bose-Einstein condensate symbolic computation

Approximate solutions of nonlinear PDEs by the invariant expansion

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Chinese physics B 2012年第12期21卷 31-36页

作者：吴江龙楼森岳 Faculty of science Ningbo University center of nonlinear science Ningbo University

It is difficult to obtain exact solutions of the nonlinear partial differential equations （PDEs） due to their complexity and nonlinearity, especially for non-integrable systems. In this paper, some reasonable approximations of real physics are considered, and the invariant expansion is proposed to solve real nonlinear systems. A simple invariant expansion with quite a universal pseudopotential is used for some nonlinear PDEs such as the Korteweg-de Vries （KdV） equation with a fifth-order dispersion term, the perturbed fourth-order KdV equation, the KdV-Burgers equation, and a Boussinesq-type equation.

关键词： approximate solution invariant expansion Mobious transformation invariance

Einstein Probe discovery of EP240408a: A peculiar X-ray transient with an intermediate timescale

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science China(physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 222-240页

作者： Wenda Zhang Weimin Yuan Zhixing Ling Yong Chen Nanda Rea Arne Rau Zhiming Cai Huaqing Cheng Francesco Coti Zelati Lixin Dai Jingwei Hu Shumei Jia Chichuan Jin Dongyue Li Paul O’Brien Rongfeng Shen Xinwen Shu Shengli Sun Xiaojin Sun Xiaofeng Wang Lei Yang Bing Zhang Chen Zhang Shuang-Nan Zhang Yonghe Zhang Jie An David Buckley Alexis Coleiro Bertrand Cordier Liming Dou Rob Eyles-Ferris Zhou Fan Hua Feng Shaoyu Fu Johan P.U.Fynbo Lluis Galbany Saurabh W.Jha Shuaiqing Jiang Albert Kong Erik Kuulkers Weihua Lei Wenxiong Li Bifang Liu Mingjun Liu Xing Liu Yuan Liu Zhu Liu Chandreyee Maitra Alessio Marino Itumeleng Monageng Kirpal Nandra Jeremy Sanders Roberto Soria Lian Tao Junfeng Wang Song Wang Tinggui Wang Zhongxiang Wang Qingwen Wu Xuefeng Wu Dong Xu Yanjun Xu Suijian Xue Yongquan Xue Zijian Zhang Zipei Zhu Hu Zou Congying Bao Fansheng Chen Houlei Chen Tianxiang Chen Wei Chen Yehai Chen Yifan Chen Chenzhou Cui Weiwei Cui Yanfeng Dai Dongwei Fan Ju Guan Dawei Han Dongjie Hou Haibo Hu Maohai Huang Jia Huo Zhenqing Jia Bowen Jiang Ge Jin Chengkui Li Junfei Li Longhui Li Maoshun Li Wei Li Zhengda Li Tianying Lian Congzhan Liu Heyang Liu Huaqiu Liu Fangjun Lu Laidan Luo Jia Ma Xuan Mao Haiwu Pan Xin Pan Liming Song Hui Sun Yunyin Tan Qingjun Tang Yihan Tao Hao Wang Juan Wang Lei Wang Wenxin Wang Yilong Wang Yusa Wang Qinyu Wu Haitao Xu Jingjing Xu Xinpeng Xu Yunfei Xu Zhao Xu Changbin Xue Yulong Xue Ailiang Yan Haonan Yang Xiongtao Yang Yanji Yang Juan Zhang Mo Zhang Wenjie Zhang Zhen Zhang Zhen Zhang Ziliang Zhang Donghua Zhao Haisheng Zhao Xiaofan Zhao Zijian Zhao Hongyan Zhou Yilin Zhou Yuxuan Zhu Zhencai Zhu National Astronomical Observatories Chinese Academy of sciences School of Astronomy and Space sciences university of Chinese Academy of sciences Key Laboratory of Particle Astrophysics Institute of High Energy physics Chinese Academy of sciences Institute of Space sciences (ICE) CSIC Institut d’Estudis Espacials de Catalunya (IEEC) Max Planck Institute for Extraterrestrial physics Innovation Academy for Microsatellites Chinese Academy of sciences department of physics university of Hong Kong School of physics and Astronomy university of Leicester School of physics and Astronomy Sun Yat-sen university department of physics Anhui Normal university Shanghai Institute of Technical physics Chinese Academy of sciences physics department Tsinghua university Nevada center for Astrophysics university of Nevada Las Vegas department of physics and Astronomy university of Nevada Las Vegas South African Astronomical Observatory department of Astronomy university of Cape Town department of physics university of the Free State Université Paris Cité CNRS Astroparticule et Cosmologie Université Paris Cité CEA Paris-Saclay IRFU/DAp-AIM department of Astronomy Guangzhou university Cosmic Dawn center (DAWN) Niels Bohr Institute university of Copenhagen department of physics and Astronomy Rutgers the State university of New Jersey Institute for Cosmic Ray Research The university of Tokyo ESA/ESTEC department of Astronomy School of physics Huazhong university of science and Technology INAF-Osservatorio Astrofisico di Torino Sydney Institute for Astronomy School of physics The university of Sydney department of Astronomy Xiamen university Institute for Frontiers in Astronomy and Astrophysics Beijing Normal university department of Astronomy university of science and Technology School of Astronomy and Space sciences university of science and Technology of China Institute of Deep Space sciences Deep Space Exploration Laboratory department of Astronomy School of physics and Astronomy Yunnan university Shanghai Astronomical Observatory Chi

We report the discovery of a peculiar X-ray transient,EP240408a,by Einstein Probe （EP） and follow-up studies made with EP,Swift,NICER,GROND,ATCA and other ground-based multiwavelength *** new transient was first detected with Wide-field X-ray Telescope （WXT） on board EP on April 8th,2024,manifested in an intense yet brief X-ray flare lasting for *** flare reached a peak flux of 3.9×10-9erg cm-2s-1in 0.5-4 ke V,～300 times brighter than the underlying X-ray emission detected throughout the *** and more precise follow-up observations by EP/FXT,Swift and NICER confirmed the finding of this new *** X-ray spectrum is non-thermal in 0.5-10 ke V,with a power-law photon index varying *** X-ray light curve shows a plateau lasting for ～4 d,followed by a steep decay till becoming undetectable ～10 d after the initial *** on its temporal property and constraints from previous EP observations,an unusual timescale in the range of 7-23 d is found for EP240408a,which is intermediate between the commonly found fast and long-term *** counterparts have been found in optical and near-infrared,with the earliest observation at 17 h after the initial X-ray detection,suggestive of intrinsically weak emission in these *** demonstrate that the remarkable properties of EP240408a are inconsistent with any of the transient types known so far,by comparison with,in particular,jetted tidal disruption events,gamma-ray bursts,X-ray binaries and fast blue optical *** nature of EP240408a thus remains an *** suggest that EP240408a may represent a new type of transients with intermediate timescales of the order of～10 *** detection and follow-ups of more of such objects are essential for revealing their origin.

关键词： X-ray transients ${\bm~{Einstein~~Probe}}$