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Showing 50 of 144 papers in Astronomy

AGNs in the Extremely Overdense Galaxy Region BOSS~1441: A Chandra Observation Postprint The discovery of galaxy protoclusters at high redshifts provides a unique opportunity to study the early evolution of galaxies and their central supermassive black holes in dense environments. In this study,...

Jiahua Wu, Liming Dou, Zheng Cai, Yanli Ai, Shiwu Zhang, Zhenya Zheng, Xiaohui Fan, Yuanyuan Su, Jianfeng Wu, Liming Dou
2025-12-09 ChinaXiv: chinaxiv-202512.00068 Original EN

We present a Chandra/ACIS-I study of X-ray sources in BOSS~1441, a protocluster at $z=2.32\pm0.02$ that exhibits a prominent overdensity of Ly$\alpha$ emitters (LAEs).Using a 45\,ks observation, we identify seven X-ray sources spatially coincident with LAE density peaks. The average X-ray photon ind…

From Singularity Elimination to Galactic Rotation—Quantum Gravity Effects with Logarithmic Corrections

Yellow Sea, Yellow Sea
2025-12-08 ChinaXiv: chinaxiv-202512.00052 Mixed Source

Based on a unified non-perturbative quantum gravity framework, this paper systematically elaborates on the cross-scale universality of quantum gravity correction terms containing logarithmic components. At the microscopic scale of black holes, these terms dynamically resolve singularities through a …

Evaluating the regional consistency of astronomical observing conditions across Dome A

Kaiwen Zheng, Kun Ma, Jiali Chen, Haosi Song, Tiancong Zhang, Shiyi Wang, Han Wang, Peng Jiang, Xiaoyan Li, Peng Jiang, Xiaoyan Li
2025-12-03 ChinaXiv: chinaxiv-202512.00033 Original EN

With excellent seeing conditions, ultra-low infrared background noise, high frequency of space debris transits, and continuous polar night coverage, Dome A in Antarctica has become an ideal platform for ground-based astronomy and space situational monitoring. As a crucial observatory site for intern…

Design and analysis of a direct-drive motor for astronomical telescopes in extreme Antarctic environments (Postprint)

Yao Zhang, Qingshan Li, Zhengyang Li, Xiaoyan Li, Zhenshuai Yan, Jia’nan Cong, Zhengyang Li
2025-12-03 ChinaXiv: chinaxiv-202512.00034 Original EN

Effective motors are crucial for driving astronomical telescopes, especially for those operating in Antarctica, where the harsh environment and operating conditions, including extreme low temperature, ice/snow accumulation, low power consumption, and unattended operation, introduce challenges to the…

RASI: the Robotic All-Sky narrowband Imager Preprint

Yuxin Xin, Baoli Lun, Zejun Hu, Yue Zhong, Kai Ye, Hongying Xu, Yufeng Fan, Bin Li, Dehong Huang, Yuxin Xin, Baoli Lun, Zejun Hu
2025-12-03 ChinaXiv: chinaxiv-202512.00035 Original EN

We report a new standalone Robotic All-Sky narrowband Imager (RASI) for auroral and airglow studies. RASI has new optics and an electromechanical system, low operation and installation costs, easy deployment and fully automatic features. The new optics provide an all-sky field of view with excellent…

Probing the cosmological 21 cm global signal from the Antarctic ice sheet Postprint

Shijie Sun, Jiaqin Xu, Minquan Zhou, Shenzhe Xu, Fengquan Wu, Haoran Zhang, Juyong Zhang, Bin Ma, Zhaohui Shang, Xuelei Chen, Xuelei Chen
2025-12-03 ChinaXiv: chinaxiv-202512.00036 Original EN

The redshifted 21 cm line, arising from neutral hydrogen, offers a unique probe into the intergalactic medium and the first stars and galaxies formed in the early universe. However, detecting this signal is a challenging task because of artificial radio-frequency interference (RFI) and systematic er…

An optimization strategy for reliable Antarctic telescope control systems (Preprint)

Yun Li, Xiaoyan Li, Shihai Yang, Zhenshuai Yan, Yanpeng Guo, Zhuangzhuang Deng, Cong Pan, Zhengyang Li, Bozhong Gu, Michael C. B. Ashley, Shihai Yang
2025-12-03 ChinaXiv: chinaxiv-202512.00037 Original EN

Antarctic telescopes, especially those located at Dome A, face significant reliability challenges owing to the extremely harsh working environment, among which the reliability of the control system is critical in ensuring stable operation. This paper describes various factors affecting the reliabili…

Performance analysis and strategy optimization of mechanical defrosting for an Antarctic near-infrared telescope using aperture photometry (Postprint)

Jiali Chen, Zhengyang Li, Zhixu Wu, Jia’nan Cong, Zichong Zhang, Kaiwen Zheng, Zhengyang Li, Zhixu Wu
2025-12-03 ChinaXiv: chinaxiv-202512.00038 Original EN

Dome A, in Antarctica, offers an exceptional site for ground-based infrared astronomy, with its extremely low atmospheric infrared background noise and excellent seeing conditions. However, deploying near-infrared telescopes in the harsh environment of Antarctica faces the critical challenge of fros…

Data matching and association based on the arc-segment difference method (Preprint)

Jiannan Sun, Zhe Kang, Zhenwei Li, Cunbo Fan, Cunbo Fan
2025-12-03 ChinaXiv: chinaxiv-202512.00039 Original EN

In response to the issue of fuzzy matching and association when optical observation data are matched with the orbital elements in a catalog database, this paper proposes a matching and association strategy based on the arcsegment difference method. First, a matching error threshold is set to match t…

Target imaging simulation method for ground-based system based on signal-to-noise ratio postprint

Chunxu Ren, Yun Li, Yanzhao Li, Weihua Gao, Wenlong Niu, Xiaodong Peng, Yun Li
2025-12-03 ChinaXiv: chinaxiv-202512.00040 Original EN

Space target imaging simulation technology is an important tool for space target detection and identification, with advantages that include high flexibility and low cost. However, existing space target imaging simulation technologies are mostly based on target magnitudes for simulations, making it d…

Stellar flare detection methods in TESS data: application and performance study (Preprint)

Min Li, Liang Wang, Zhiqiang Zou, Ali Luo, Bo Qiu, Peng Jia, Ying Shan, Liang Wang, Zhiqiang Zou
2025-12-03 ChinaXiv: chinaxiv-202512.00041 Original EN

The detection of stellar flares is crucial to understanding dynamic processes at the stellar surface and their potential impact on surrounding exoplanetary systems. Extensive time series data acquired by the Transiting Exoplanet Survey Satellite (TESS) offer valuable opportunities for large-scale fl…

Instant determination of polar motion with tri-static common view lunar laser ranging (Preprint) Abstract: Polar motion is one of the fundamental parameters for the transformation between the terrestrial reference system and the celestial reference system. Currently, the determination of polar mo...

Zhipeng Liang, Chengzhi Liu, Yanning Zheng, Xue Dong, Chengzhi Liu
2025-12-03 ChinaXiv: chinaxiv-202512.00042 Original EN

A method is presented for determining instant values of Earth’s polar motion (PM) using a set of lunar laser ranging (LLR) measurements acquired simultaneously by tri-static common view (TCV) at three LLR stations in Europe. We developed a model of the LLR TCV measurements, then formulated the linea…

Stray light analysis for the AIMS Telescope preprint

Biyuan Gao, Dongguang Wang, Yingzi Sun, Yuliang Shen, Xiao Yang, Junfeng Hou, Yingzi Sun
2025-12-02 ChinaXiv: chinaxiv-202512.00045 Original EN

Stray light has a significant effect on the overall performance of telescopes, particularly for infrared solar telescopes, in which internal thermal radiation causes additional stray light sources. We establish a 3-dimensional model using stray light theory and the real opto-mechanical structure of …

Optimization of compressed sensing-based radio interferometric imaging: hyperparameter selection postprint Radio interferometric imaging is a typical inverse problem. In recent years, imaging algorithms based on compressed sensing and deep learning have been widely applied in this field. However,...

Haoming Dai, Li Deng, Li Deng
2025-12-02 ChinaXiv: chinaxiv-202512.00046 Original EN

Radio interferometric imaging samples visibility data in the spatial frequency domain and then reconstructs the image. Because of the limited number of antennas, the sampling is usually sparse and noisy. Compressed sensing-based on convex optimization is an effective reconstruction method for sparse…

Radio astronomy observation on distributed deep space radar: A prototype experiment (Preprint)

Xue Chen, Yuyang Ma, Xiaoyun Ma, Junjie Huang, Zehua Dong, Zegang Ding, Xiaoyun Ma, Zehua Dong
2025-12-02 ChinaXiv: chinaxiv-202512.00047 Original EN

Earth-based deep space radar studies celestial bodies by both transmitting and receiving radio waves, whereas radio telescopes only work passively. On the operational level, radar missions use only short observation times, which leaves a large portion of the time available for astronomical observati…

A Preliminary Study on Stellar Energy for High School Students

Li Li, Li Li
2025-12-01 ChinaXiv: chinaxiv-202512.00050 Mixed Source

Stellar energy is a crucial component of stellar research. Descriptions regarding stellar energy typically necessitate the extensive use of advanced mathematics. However, in this paper, the author ingeniously replaces the sections requiring advanced mathematical descriptions with simple high school …

Non-renormalizable Singularity Resolution and Black Hole Shadow Verification

Yellow Sea, Yellow Sea
2025-11-28 ChinaXiv: chinaxiv-202507.00323 Mixed Source

This paper proposes a novel non-perturbative quantum gravity framework based on quantum topological structures. By introducing "quantum vortices" to characterize the topological order of statistical averages of microscopic particles and embedding the AdS/CFT holographic duality, black hole singulari…

A Simple Model of Coherent Emission Confronting a Number of Puzzles on Pulsars, Magnetars, and Fast Radio Bursts

Biping Gong
2025-10-14 ChinaXiv: chinaxiv-202507.00212 Original EN

Five decades after the discovery of radio pulsars, main stream theories based on polar cap still suffer from difficulties in both self-consistency and confrontation with observations[1]. Increasing observation of individual subpulses of pulsars, i.e., high brightness temperature, highly polarized, a…

Narrow-Band Optical Imaging Observations and Analysis of the MASTA and WFST Wide-Field Telescopes (Postprint)

Xu Xiao, Lou Zheng, Ping Yiding, Dong Yunfen, Zheng Xianzhong
2025-10-11 ChinaXiv: chinaxiv-202510.00050 Mixed Source

In optical systems with small focal ratios, the optical performance of narrowband filters is significantly affected by the telescope's optical system and the angle of incidence of light. From the center of the field of view to the edge, the deviation of the incident angle gradually increases, causin…

Analysis of Clock Difference Prediction Algorithms for Domestic Optically Pumped Cesium Atomic Clocks (Postprint)

Du Hongqiang, Gong Jianjun, Wu Dan, Qu Lili, Wu Wenjun, Dong Shaowu, Zhang Shougang
2025-10-11 ChinaXiv: chinaxiv-202510.00051 Mixed Source

Cesium atomic clocks are the key core equipment in modern atomic timekeeping. In recent years, the domestically produced optically pumped cesium atomic clock TA1000 has been widely applied in timekeeping operations. The clock difference prediction algorithm for atomic clocks is one of the factors af…

Milky Way Imaging Scroll Painting (10°≤l≤20°) 13CO & C18O Dense Structure Morphological Analysis Postprint

Xiao Yanshan, Zhang Haixia, Huang Yao, Jiang Zhibo, Chen Zhiwei, Zheng Sheng, Zhang Peng, Luo Xiaoyu, Jiang Yu, Pan Xuejiao
2025-10-11 ChinaXiv: chinaxiv-202510.00053 Mixed Source

Dense molecular cloud clumps are sites of star formation, and their morphological characteristics are closely related to the physical properties of molecular gas. This work is based on data from the 13.7 m millimeter-wave radio telescope of Purple Mountain Observatory, covering galactic longitude (g…

Postprint: Multi-band Radiative Relations of Fermi Blazars

Liu Xintao, Zhang Haojing
2025-10-11 ChinaXiv: chinaxiv-202510.00054 Mixed Source

We collected multi-band radiation flux densities for a blazar sample from the Fermi Large Area Telescope Fourth Source Catalog Data Release 3 (4FGL-DR3), with the collected data covering radio at 1.4 and 143 GHz, near-infrared (J, H, and K), optical (u, g, r, i, and z), ultraviolet (far ultraviolet …

Search for Young Stars and Analysis of Their Properties in the IC 5146 Star-Forming Region (Postprint)

Xiao Fan, Wang Xiaolong, Wang Fan, Fang Min, Zhang Miaomiao
2025-10-11 ChinaXiv: chinaxiv-202510.00055 Mixed Source

Identifying young stars in star-forming regions is crucial for a comprehensive understanding of the star formation process. This study uses Gaia (Global Astrometric Interferometer for Astrophysics) astrometric data to identify and analyze young stars in the IC 5146 star-forming region. First, Gaia a…

Postprint: A Study of the Spatial Distribution of Infall Candidates in Molecular Cloud Clumps

Wan Yujie, Jiang Zhibo, Jiang Yu, Chen Zhiwei
2025-10-11 ChinaXiv: chinaxiv-202510.00056 Mixed Source

Stars form from the gravitational collapse of dense molecular cloud cores. Investigating the specific locations within molecular cloud clumps where this collapse motion preferentially occurs will help elucidate star formation across different regions of molecular cloud clumps, providing additional i…

Comparison of Long-term Mid-infrared Variability between Broad-line and Narrow-line Seyfert 1 Galaxies: Postprint

Hu Zhipeng, Mao Lisheng
2025-10-11 ChinaXiv: chinaxiv-202510.00057 Mixed Source

Utilizing archival data from the Wide-field Infrared Survey Explorer (WISE), we compared the long-term mid-infrared variability amplitudes of Broad-line Seyfert 1 (BLSy1) galaxies and Narrow-line Seyfert 1 (NLSy1) galaxies. Furthermore, we analyzed the correlations between long-term mid-infrared var…

Research on Cloud Cover Monitoring Schemes for Radio Telescope Observatory Sites (Postprint)

Hailong Zhang, Dengrong Lu, Jixian Sun, Jibin Li, Xuguo Zhang
2025-10-11 ChinaXiv: chinaxiv-202510.00060

In the site selection process for millimeter-wave and submillimeter-wave radio astronomical telescopes, in order to fully understand the cloud cover information of candidate astronomical sites, it is essential to design an all-sky camera system applicable to field environments. Therefore, according …

WST and SDI On-Orbit Radiometric Calibration Postprint

Li Gen, Li Ying, Li Qiao, Li Hui
2025-10-11 ChinaXiv: chinaxiv-202510.00061 Mixed Source

The Lyman-alpha Solar Telescope (Ly$\alpha$ Solar Telescope, LST) is one of the payloads on the Advanced Space-based Solar Observatory (ASO-S, Chinese name "Kuafu-1") satellite, which includes three scientific instruments: the White-light Solar Telescope (WST), the Solar Disk Imager (SDI), and the S…

Optimization Design for Reflector Antenna Panel Fitting Based on Particle Swarm Algorithm (Post-print)

Zhang Wenyang, Wu Yang, Liu Shengwen
2025-10-10 ChinaXiv: chinaxiv-202510.00036 Mixed Source

Taking a 40 m offset Cassegrain antenna as an example, this study analyzes different small panel fitting schemes to investigate the relationship between small panel design and surface accuracy, verifying that the reflector surface accuracy is proportional to the square of the circumferential and axi…

Postprint: Evaluation Method for Optical Fiber Mode Scrambling Performance Based on Fourier Spectrum

Pang Yuchen, 彭子夫, Geng Tao, Sun Weimin, Yan Yunxiang
2025-10-10 ChinaXiv: chinaxiv-202510.00037

Fiber optic mode scrambling technology for high-resolution spectroscopic observations can effectively improve radial velocity measurement precision, providing a powerful tool for research on cutting-edge scientific problems such as the search for Earth-like planets. Currently, the impact of mode noi…

Long-term Prediction and Accuracy Assessment of EOP Based on China's Independent Observations and Solutions: Postprint

Xu Xueqing, Guo Li, Zhou Weili, Zhang Zhibin, Song Shuli, Wang Guangli, Qi Chaoxiang
2025-10-10 ChinaXiv: chinaxiv-202510.00038 Mixed Source

Earth rotation can be described using Earth Orientation Parameters (EOP). As key parameters connecting the celestial and terrestrial reference frames, EOP constitute important spatiotemporal datum parameters. Due to latency in observational data processing, real-time applications of EOP must be real…

Testing the No-Hair Theorem Using Precessing Gravitational-Wave Bursts from Supermassive Binary Black Holes Postprint

Zhaowei Zhang, Han Wenbiao
2025-10-10 ChinaXiv: chinaxiv-202510.00039 Mixed Source

Future space-based gravitational wave detectors (such as LISA and Taiji) will detect gravitational wave events from supermassive binary black hole mergers. Highly precessing supermassive binary black holes, in addition to emitting traditional inspiral-merger-ringdown gravitational wave signals, can …

Postprint: Age Determination of r-process Enhanced Metal-Poor Stars Using Th/U Nuclear Chronometry

Long Yin, Chen Menghua
2025-10-10 ChinaXiv: chinaxiv-202510.00041 Mixed Source

Metal-poor stars are stars that formed in the early universe, preserving chemical signatures from early nucleosynthesis and providing crucial clues for investigating heavy-element nucleosynthesis mechanisms and the chemical evolution of the early cosmos. Based on Th/U nucleocosmochronology, we have …

Postprint: Selection Effects in Wide Binaries

Liu Di, Zhang Peng, Tian Haijun, Liu Gaochao, Yang Xiangming, Xiong Zhuang
2025-10-10 ChinaXiv: chinaxiv-202510.00042 Mixed Source

Wide binary stars are systems composed of two widely separated celestial bodies orbiting a common center of mass, with their physical projected separation being the most direct observable quantity. Using high-purity wide binary stars within 1 kpc of the solar neighborhood as a test sample, anomalous…

Low-frequency Extragalactic Radio Point Source Sample Review Postprint

Jinyang Lin, Zhu Zhenghao, Ma Renyi
2025-10-10 ChinaXiv: chinaxiv-202510.00043

Low-frequency radio point sources are of significant importance in astronomical research, serving not only as crucial probes for studying galaxy evolution history but also as the primary foreground contaminants for detecting Epoch of Reionization signals. Low-frequency observations are essential for…

Postprint on the Current Status of Small Body Observations and Research

Liu Yanjie, Zhao Haibin
2025-10-10 ChinaXiv: chinaxiv-202510.00045 Mixed Source

Small Solar System bodies with perihelion distances less than 0.307 AU/66 R⊙ are known as near-Sun small bodies. The extreme solar heating and high-temperature magnetized plasma environment they encounter can reveal intrinsic information about these bodies and facilitate investigations of the near-S…

Operational Framework for Time Reversal in General Relativity

Peng Li, Peng Li
2025-08-24 ChinaXiv: chinaxiv-202508.00349 Original EN

It transforms the passive role of "time as an evolution parameter" by treating proper time (τ) as the dependent variable to inversely derive motion velocity, gravitational field strength, and mass distribution from observed time differences (e.g., Δτ/Δt). It defines the time flow ratio between diffe…

Postprint: Advances in Insight-HXMT Observations of Isolated Pulsars and Accreting Millisecond Pulsars

Ge Mingyu, Li Zhaosheng
2025-08-19 ChinaXiv: chinaxiv-202508.00310 Mixed Source

Insight-HXMT (Insight-Hard X-ray Modulation Telescope) is China's first space X-ray astronomical satellite, whose primary scientific objectives are to study compact objects such as black holes and neutron stars and to monitor violent explosive phenomena such as gamma-ray bursts; isolated X-ray pulsa…

Insight-HXMT Broadband Observations of Thermonuclear Bursts Postprint

Chen Yupeng
2025-08-19 ChinaXiv: chinaxiv-202508.00312 Mixed Source

Since its successful launch in 2017, the Insight Hard X-ray Modulation Telescope (Insight-HXMT) has been operating continuously for over 8 years, accumulating massive observational data. In observations of multiple thermonuclear burst sources, it has detected more than 200 thermonuclear burst events…

Research Progress on Quasi-Periodic Oscillation Phenomena Based on Insight-HXMT Observations (Postprint)

Zhang Liang, Qu Jinlu, Zhang Shu
2025-08-19 ChinaXiv: chinaxiv-202508.00315 Mixed Source

Quasi-Periodic Oscillation (QPO) phenomena are ubiquitous in the light curves of X-ray binaries, and are generally believed to originate from accretion flows in close proximity to the compact star; consequently, QPOs serve as important probes for testing general relativistic effects in strong gravit…

Magnetic Field Transport and Jets in Black Hole X-ray Binaries (Postprint)

Yang Shuaikang, You Bei
2025-08-19 ChinaXiv: chinaxiv-202508.00316 Mixed Source

Black Hole X-Ray Binary (BHXRB) is a binary system composed of a central compact black hole and its companion star. During its outburst phase, it is always accompanied by multi-wavelength radiation. With the development of multi-wavelength astronomy, a general picture of the physical processes behin…

Insight-HXMT Measurements of Black Hole Fundamental Parameters: A Research Overview (Postprint)

Wang Wei, Zhu Haifan
2025-08-19 ChinaXiv: chinaxiv-202508.00317 Mixed Source

Systematically reviews the primary measurement methods for the fundamental parameters of black holes—mass and spin—and briefly introduces distance measurement techniques for black hole binary systems. Through case studies, it demonstrates the importance of precise distance measurement for the correc…

Insight-HXMT Six-Year Galactic Plane Scanning Survey: Postprint of the Broad X-ray Energy Band Monitored Source Catalog

Liao Jinyuan, Guan Ju, Wang Chen
2025-08-19 ChinaXiv: chinaxiv-202508.00318 Mixed Source

This paper reviews the 6-year Galactic Plane Scan Survey conducted by Insight-HXMT (Insight Hard X-ray Modulation Telescope, Insight-HXMT), focusing on the monitoring and analysis of known X-ray sources in the Galactic plane. During the first six years of Insight-HXMT's in-orbit operation, it perfor…

Insight-HXMT Six-Year In-Orbit Background Review Postprint

Liao Jinyuan
2025-08-19 ChinaXiv: chinaxiv-202508.00319 Mixed Source

This paper reviews the background characteristics of the Insight-Hard X-ray Modulation Telescope (Insight-HXMT) during the first 6 years of in-orbit operation, including the geographical distribution, energy spectrum, temporal variability characteristics, and long-term evolution of the in-orbit back…