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Prospects for Observing High-redshift Radio-loud Quasars in the SKA Era: Paving the Way for 21-cm Forest Observations

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arXiv 2024年

作者： Niu, Qi Li, Yichao Xu, Yidong Guo, Hong Zhang, Xin Liaoning Key Laboratory of Cosmology and Astrophysics College of Sciences Northeastern University Shenyang110819 China National Astronomical Observatories Chinese Academy of Sciences Beijing100101 China Key Laboratory of Radio Astronomy and Technology Chinese Academy of Sciences Beijing100101 China Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai200030 China National Frontiers Science Center for Industrial Intelligence and Systems Optimization Northeastern University Shenyang110819 China MOE Key Laboratory of Data Analytics and Optimization for Smart Industry Northeastern University Shenyang110819 China

The 21-cm forest is a sensitive probe for the early heating process and small-scale structures during the epoch of reionization (EoR), to be realized with the upcoming Square Kilometre Array (SKA). Its detection relies on the availability of radio-bright background sources, among which the radio-loud quasars are very promising, but their abundance during the EoR is still poorly constrained due to limited observations. In this work, we use a physics-driven model to forecast future radio-loud quasar observations. We fit the parameters of the model using observational data of high-redshift quasars. Assuming Eddington accretion, the model yields an average lifetime of tq ∼ 105.5yr for quasars at z ∼ 6, consistent with recent results obtained from quasar proximity zone observation. We show that if the radio-loud fraction of quasars evolves with redshift, it will significantly reduce the abundance of observable radio-loud quasars in the SKA era, making 21-cm forest studies challenging. With a constant radio-loud fraction, our model suggests that a one-year sky survey conducted with SKA-LOW has the capability to detect approximately 20 radio-loud quasars at z ∼ 9, with sufficient sensitivity to resolve individual 21-cm forest lines. Copyright © 2024, The Authors. All rights reserved.

关键词： Radio astronomy

Joint observations of late universe probes: cosmological parameter constraints from gravitational wave and Type Ia supernova data

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arXiv 2024年

作者： Zheng, Jie Liu, Xiao-Hui Qi, Jing-Zhao Gravitational Wave Observatory Henan Academy of Sciences Zhengzhou450046 China National Astronomical Observatories Chinese Academy of Sciences Beijing100101 China School of Astronomy and Space Science University of Chinese Academy of Sciences Beijing100049 China Department of Physics College of Sciences MOE Key Laboratory of Data Analytics and Optimization for Smart Industry Northeastern University Shenyang110819 China

The growing tensions between the early Universe and the late Universe increasingly highlight the importance of developing precise probes for late cosmology. As significant late-Universe probes, Type Ia supernovae (SNe Ia) and gravitational waves (GWs) can provide measurements of relative and absolute distances, respectively. Their complementary nature is likely to break the degeneracies among cosmological parameters, thereby yielding more precise constraints. In this study, we use 43 gravitationalwave sources from the Third LIGO-Virgo-KAGRA Gravitational-Wave Transient Catalog (GWTC-3) and 1590 SNe Ia from Pantheon+ compilation to constrain the dark energy models, as an attempt to achieve precise late-Universe cosmological constraints. For the dark siren GW event, we estimate the corresponding redshift using the binary black hole redshift distribution model. The combination of GW and SNe Ia data could provide the precision on the Hubble constant H0 and the present matter density Ωm of approximately 20% and 8% for the ΛCDM model. If we consider the equation of state of dark energy w, the combination sample constrain the precision of w to approximately 30%. Although the combination of GW and SNe Ia observations effectively breaks degeneracies among various cosmological parameters, yielding more stringent constraints, the precision of these constraints still does not meet the stringent standards required by precision cosmology. However, it is reasonable to anticipate that, in the near future, the joint observations of GWs and SNe Ia will become a powerful tool, particularly in the late Universe, for the precise measurement of cosmological parameters. Copyright © 2024, The Authors. All rights reserved.

关键词： Gravity waves

A learning-based solution method for practical slab allocation problem in multiple hot rolling lines

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A I I E Transactions

A I I E Transactions 2024年第9期56卷

作者： Ying Meng Qingxin Guo Qingyang Wang Haichao Wang a National Frontiers Science Center for Industrial Intelligence and Systems Optimization Northeastern University Shenyang Chinab Key Laboratory of Data Analytics and Optimization for Smart Industry (Northeastern University) Ministry of Education China b Key Laboratory of Data Analytics and Optimization for Smart Industry (Northeastern University) Ministry of Education Chinac Liaoning Engineering Laboratory of Data Analytics and Optimization for Smart Industry Northeastern University Shenyang China b Key Laboratory of Data Analytics and Optimization for Smart Industry (Northeastern University) Ministry of Education Chinad Liaoning Key Laboratory of Manufacturing System and Logistics Optimization Northeastern University Shenyang China

Steel slabs are key in-process products in the steel production process. The slab allocation problem is to allocate slabs to suitable orders by considering complicated technical restrictions and multiple management requirements. In practice, thousands of slabs in multiple production lines should be allocated to orders. Due to the complexity and large scale of the problem, it takes planners a long time to make decisions, and the obtained allocation schemes are usually ineffective because of the myopic nature of the rule-based methods. In this article, we present a learning-based solution method for solving a practical slab allocation problem in multiple hot rolling lines. We formulate the problem as an integer programming model, then a data-based method is adopted to evaluate the mismatching cost between slabs and orders. To effectively solve the large-sized problem, a learning-based decomposition strategy is proposed to decompose the original problem into several small-sized subproblems. Then, a branch-and-price algorithm is proposed to optimally solve the subproblems. To further speed up the solution process, a primal heuristics based on column generation is designed to solve the large-sized subproblems. The solution methods have been implemented in a steel company and effectively increased slab utilization and reduced production cost.

关键词： Slab allocation combinatorial optimization branch-and-price learning

Forecasts for constraining Lorentz-violating damping of gravitational waves from compact binary inspirals

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Physical Review D 2024年第10期109卷 104022-104022页

作者： Bo-Yang Zhang (张博扬) Tao Zhu (朱涛) Jing-Fei Zhang (张敬飞) Xin Zhang (张鑫) Key Laboratory of Cosmology and Astrophysics (Liaoning) and College of Sciences Northeastern University Shenyang 110819 China Institute for Theoretical Physics and Cosmology Zhejiang University of Technology Hangzhou 310032 China United Center for Gravitational Wave Physics (UCGWP) Zhejiang University of Technology Hangzhou 310032 China Key Laboratory of Data Analytics and Optimization for Smart Industry (Ministry of Education) Northeastern University Shenyang 110819 China National Frontiers Science Center for Industrial Intelligence and Systems Optimization Northeastern University Shenyang 110819 China

Violation of Lorentz symmetry can result in two distinct effects in the propagation of the gravitational waves (GWs). One is a modified dispersion relation and another is a frequency-dependent damping of GWs. While the former has been extensively studied in the literature, in this paper we concentrate on the frequency-dependent damping effect that arises from several specific Lorentz-violating theories, such as spatial covariant gravities, Hořava-Lifshitz gravities, etc. This Lorentz-violating damping effect changes the damping rate of GWs at different frequencies and leads to an amplitude correction to the GW waveform of compact binary inspiral systems. With this modified waveform, we then use the Fisher information matrix to investigate the prospects of constraining the Lorentz-violating damping effect with GW observations. We consider both ground-based and space-based GW detectors, including the advanced LIGO, Einstein Telescope, Cosmic Explorer (CE), Taiji, TianQin, and LISA. Our results indicate that the ground-based detectors in general give tighter constraints than those from the space-based detectors. Among the considered three ground-based detectors, CE can give the tightest constraints on the Lorentz-violating damping effect, which improves the current constraint from LIGO-Virgo-KAGRA events by about 8 times.

关键词： Alternative gravity theories Gravitational waves

Author Correction: CRISPR screens reveal convergent targeting strategies against evolutionarily distinct chemoresistance in cancer

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Nature communications 2025年第1期16卷 1569页

作者： Chunge Zhong Wen-Jie Jiang Yingjia Yao Zexu Li You Li Shengnan Wang Xiaofeng Wang Wenjuan Zhu Siqi Wu Jing Wang Shuangshuang Fan Shixin Ma Yeshu Liu Han Zhang Wenchang Zhao Lu Zhao Yi Feng Zihan Li Ruifang Guo Li Yu Fengyun Pei Jun Hu Xingzhi Feng Zihuan Yang Zhengjia Yang Xueying Yang Yue Hou Danni Zhang Dake Xu Ren Sheng Yihao Li Lijun Liu Hua-Jun Wu Jun Huang Teng Fei Key Laboratory of Bioresource Research and Development of Liaoning Province College of Life and Health Sciences Northeastern University Shenyang 110819 China. National Frontiers Science Center for Industrial Intelligence and Systems Optimization Northeastern University Shenyang 110819 China. Key Laboratory of Data Analytics and Optimization for Smart Industry (Northeastern University) Ministry of Education Shenyang 110819 China. Foshan Graduate School of Innovation Northeastern University Foshan 528311 China. Peking University Third Hospital Beijing 100191 China. Department of Colorectal Surgery the Sixth Affiliated Hospital Sun Yat-sen University Guangzhou China. Clinical Research Center the Sixth Affiliated Hospital Sun Yat-sen University Guangzhou China. Guangdong Provincial Key Laboratory of Colorectal and Pelvic Floor Diseases the Sixth Affiliated Hospital Sun Yat-sen University Guangzhou China. Guangdong Institute of Gastroenterology Guangzhou China. Department of Cardiothoracic Surgery Jinqiu Hospital of Liaoning Province Shenyang China. Department of Thoracic Surgery The Fourth Affiliated Hospital of China Medical University Shenyang China. Key Laboratory for Anisotropy and Texture of Materials (Ministry of Education) School of Materials Science and Engineering Northeastern University Shenyang China. BeiGene Institute BeiGene (Shanghai) Research & Development Co. Ltd 200131 Shanghai China. Key laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing) Peking University Cancer Hospital & Institute Beijing 100142 China. hjwu@***. Department of Biomedical Informatics School of Basic Medical Sciences Peking University Health Science Center Beijing 100191 China. hjwu@***. Center for Precision Medicine Multi-Omics Research Institute of Advanced Clinical Medicine Peking University Beijing 100191 China. hjwu@***. Department of Colorectal Surgery the Sixth Affiliated Hospital Sun Yat-sen University Guangzhou China. huan

Alternating current conductivity and superconducting properties of the holographic effective theory

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arXiv 2022年

作者： Liu, Yan Wang, Xi-Jing Wu, Jian-Pin Zhang, Xin Department of Physics College of Sciences Northeastern University Shenyang110819 China Center for Gravitation and Cosmology College of Physical Science and Technology Yangzhou University Yangzhou225009 China Frontiers Science Center for Industrial Intelligence and Systems Optimization Northeastern University Shenyang110819 China Key Laboratory of Data Analytics and Optimization for Smart Industry Ministry of Education Northeastern University Shenyang110819 China

We construct a holographic effective superconducting theory by considering a special gauge-axion higher derivative term. The gauge-axion coupling results in the transport behavior similar to the vortex response in the dual boundary field theory leading to non-Drude behavior of alternating current (AC) conductivity at the weak momentum dissipation. With the momentum dissipation increasing, a dip exhibits in the AC conductivity at low frequency. It is thought to be the result of a combination of the strong momentum dissipation and the gauge-axion coupling. In the superconducting phase, this gauge-axion coupling also plays a key role leading to a more evident gap at the low frequency conductivity. In addition, we also study the combined effects of the strength of momentum dissipation and various couplings among the gauge field, axion fields and the complex scalar field. Copyright © 2022, The Authors. All rights reserved.

关键词： Momentum

Prospects for weighing neutrinos in interacting dark energy models using joint observations of gravitational waves and γ-ray bursts

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arXiv 2024年

作者： Feng, Lu Han, Tao Zhang, Jing-Fei Zhang, Xin College of Physical Science and Technology Shenyang Normal University Shenyang110034 China Department of Physics College of Sciences Northeastern University Shenyang110819 China Key Laboratory of Data Analytics and Optimization for Smart Industry Ministry of Education Northeastern University Shenyang110819 China National Frontiers Science Center for Industrial Intelligence and Systems Optimization Northeastern University Shenyang110819 China

Cosmological observations can be used to weigh neutrinos, but this method is model-dependent, with results relying on the cosmological model considered. If we consider interactions between dark energy and dark matter, the neutrino mass constraints differ from those derived under the standard model. On the contrary, gravitational wave (GW) standard siren observations can measure absolute cosmological distances, helping to break parameter degeneracies inherent in traditional cosmological observations, thereby improving constraints on neutrino mass. This paper examines the constraints on neutrino mass within interacting dark energy (IDE) models and explores how future GW standard siren observations could enhance these results. For multi-messenger GW observations, we consider the joint observations of binary neutron star mergers by third-generation ground-based GW detectors and short γ-ray burst observations by missions similar to the THESEUS satellite project. Using current cosmological observations (CMB+BAO+SN), we obtain an upper limit on the neutrino mass in the IDE models of 0.15 (or 0.16) eV. With the inclusion of GW data, the upper limit on the neutrino mass improves to 0.14 eV. This indicates that in the context of IDE models, the improvement in neutrino mass constraints from GW observations is relatively limited. However, GW observations significantly enhance the constraints on other cosmological parameters, such as matter density parameter, the Hubble constant, and coupling strength between dark energy and dark matter. Copyright © 2024, The Authors. All rights reserved.

关键词：

Molten-Salt Enhanced Anodic Oxidation for Upcycling Alloy Scraps

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SSRN

SSRN 2022年

作者： Zhao, Yan Chen, Xiang Qu, Jiakang Xie, Hongwei Du, Kaifa Xing, Pengfei Wang, Dihua Sun, Yuan Yin, Huayi Key Laboratory for Ecological Metallurgy of Multimetallic Mineral of Ministry of Education School of metallurgy Northeastern University Shenyang110819 China School of Resource and Environmental Science Wuhan University Wuhan430072 China Institute of Metal Research Chinese Academy of Sciences Shenyang110819 China Key Laboratory of Data Analytics and Optimization for Smart Industry of Ministry of Education Northeastern University Shenyang110819 China

Reclaiming valuable metals from spent alloys involves energy-intensive pulverization and the sluggish dissolution rate. Herein, we propose an enhanced corrosion strategy to convert alloy scraps to oxide powders. The oxidation rate reaches ~1.67 mm h-1 in molten CaCl2 -NaCl-CaO at 700 oC because Cl- excludes passivation and enables continuous oxidation. In addition, the soluble CaO in molten CaCl2-NaCl prevents the generation of transition metal chlorides, which relieves using the expensive ion-selective membrane to eliminate the parasitic reaction. Overall, the molten salt enhanced anodic corrosion provides a green and general way to achieve the pulverization and oxidation of various alloy scraps. © 2022, The Authors. All rights reserved.

关键词： Sodium chloride

Forecast for cosmological parameter estimation with gravitational-wave standard siren observation from the Cosmic Explorer

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arXiv 2020年

作者： Jin, Shang-Jie He, Dong-Ze Xu, Yidong Zhang, Jing-Fei Zhang, Xin Department of Physics College of Sciences Northeastern University Shenyang110819 China Key Laboratory for Computational Astrophysics National Astronomical Observatories Chinese Academy of Sciences Beijing100101 China Ministry of Education's Key Laboratory of Data Analytics and Optimization for Smart Industry Northeastern University Shenyang110819 China Center for High Energy Physics Peking University Beijing100080 China

The third-generation ground-based gravitational-wave (GW) detector, Cosmic Explorer (CE), is scheduled to start its observation in the 2030s. In this paper, we make a forecast for cosmological parameter estimation with gravitational-wave standard siren observation from the CE. We use the simulated GW standard siren data of CE to constrain the ΛCDM, wCDM and CPL models. We combine the simulated GW data with the current cosmological electromagnetic observations including the latest cosmic microwave background anisotropies data from Planck, the optical baryon acoustic oscillation measurements, and the type Ia supernovae observation (Pantheon compilation) to do the analysis. We find that the future standard siren observation from CE will improve the cosmological parameter estimation to a great extent, since the future GW standard siren data can well break the degeneracies generated by the optical observations between various cosmological parameters. We also find that the CE's constraining capability on the cosmological parameters is slightly better than that of the same-type GW detector, the Einstein Telescope. In addition, the synergy between the GW standard siren observation from CE and the 21 cm emission observation from SKA is also discussed. Copyright © 2020, The Authors. All rights reserved.

关键词： Gravity waves