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Morphological Classification of Infrared Galaxies Based on WISE Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-04-17 Zhi-Ren Pan, Bo Qiu, Cui-Xiang Liu, A-Li Luo, Xia Jiang, Xiao-Yu Guo
This study introduces a novel convolutional neural network, the WISE Galaxy Classification Network (WGC), for classifying spiral and elliptical galaxies using Wide-field Infrared Survey Explorer (WISE) images. WGC attains an accuracy of 89.03%, surpassing the combined use of K-means or SVM with the Color–Color method in more accurately identifying galaxy morphologies. The enhanced variant, WGC_mag
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BSN: Photometric Light Curve Analysis of Two Contact Binary Systems LS Del and V997 Cyg Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-04-17 Atila Poro, Mehmet Tanriver, Elham Sarvari, Shayan Zavvarei, Hossein Azarara, Laurent Corp, Sabrina Baudart, Asma Ababafi, Nazanin Kahali Poor, Fariba Zare, Ahmet Bulut, Ahmet Keskin
The light curve analyses and orbital period variations for two contact binary stars, LS Del and V997 Cyg, are presented in this work which was conducted in the frame of the Binary Systems of South and North project. Ground-based photometric observations were performed at two observatories in France. We used the Transiting Exoplanet Survey Satellite (TESS) data for extracting times of minima and light
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Lossless Compression Method for the Magnetic and Helioseismic Imager (MHI) Payload Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-04-10 Li-Yue Tong, Jia-Ben Lin, Yuan-Yong Deng, Kai-Fan Ji, Jun-Feng Hou, Quan Wang, Xiao Yang
The Solar Polar-orbit Observatory (SPO), proposed by Chinese scientists, is designed to observe the solar polar regions in an unprecedented way with a spacecraft traveling in a large solar inclination angle and a small ellipticity. However, one of the most significant challenges lies in ultra-long-distance data transmission, particularly for the Magnetic and Helioseismic Imager (MHI), which is the
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Prospects of the Multi-channel Photometric Survey Telescope in the Cosmological Application of Type Ia Supernovae Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-04-10 Zhenyu Wang, Jujia Zhang, Xinzhong Er, Jinming Bai
The Multi-channel Photometric Survey Telescope (Mephisto) is a real-time, three-color photometric system designed to capture the color evolution of stars and transients accurately. This telescope system can be crucial in cosmological distance measurements of low-redshift (low-z, z ≲0.1) Type Ia supernovae (SNe Ia). To optimize the capabilities of this instrument, we perform a comprehensive simulation
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Weak Merging Scenario of CLASH Cluster A209 Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-04-10 Wen-Cheng Feng, Heng Yu, Hai-Hui Zhao, Xiao-Lan Hou, Shu-Mei Jia, Cheng-Kui Li, Yu-Lin Cheng, Paolo Tozzi, Ming Sun, Yong Chen
We study the structural and dynamical properties of A209 based on Chandra and XMM-Newton observations. We obtain detailed temperature, pressure, and entropy maps with the contour binning method, and find a hot region in the NW direction. The X-ray brightness residual map and corresponding temperature profiles reveal a possible shock front in the NW direction and a cold front feature in the SE direction
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On the Performances of Estimating Stellar Atmospheric Parameters from CSST Broad-band Photometry Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-04-09 Rui-Feng Shi, Yang Huang, Xin-Yi Li, Hua-Wei Zhang
Deriving atmospheric parameters of a large sample of stars is of vital importance to understand the formation and evolution of the Milky Way. Photometric surveys, especially those with near-ultraviolet filters, can offer accurate measurements of stellar parameters, with the precision comparable to that from low/medium resolution spectroscopy. In this study, we explore the capability of measuring stellar
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A Statistical Study of Magnetic Flux Emergence in Solar Active Regions Prior to Strongest Flares Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-04-09 Alexander S. Kutsenko, Valentina I. Abramenko, Andrei A. Plotnikov
Using the data on magnetic field maps and continuum intensity for Solar Cycles 23 and 24, we explored 100 active regions (ARs) that produced M5.0 or stronger flares. We focus on the presence/absence of the emergence of magnetic flux in these ARs 2–3 days before the strong flare onset. We found that 29 ARs in the sample emerged monotonically amidst quiet-Sun. A major emergence of a new magnetic flux
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The Metallicity Dimension of the Super Earth-cold Jupiter Correlation Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-04-09 Wei Zhu
The correlation between close-in super Earths and distant cold Jupiters in planetary systems has important implications for their formation and evolution. Contrary to some earlier findings, a recent study conducted by Bonomo et al. suggests that the occurrence of cold Jupiter companions is not excessive in super-Earth systems. Here we show that this discrepancy can be seen as a Simpson’s paradox and
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Morphology Study for GeV Emission of Nearby Supernova Remnant G332.5-5.6 Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-04-09 Ming-Hong Luo, Qing-Wen Tang, Xiu-Rong Mo
A spatial template is important to study nearby supernova remnants (SNRs). For SNR G332.5-5.6, we report a Gaussian disk with a radius of about 1.°06 to be a potential good spatial model in the γ-ray band. Employing this new Gaussian disk, its GeV lightcurve shows a significant variability of about seven sigma. The γ-ray observations of this SNR could be explained well either by a leptonic model or
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How to Coadd Images. II. Anti-aliasing and PSF Deconvolution Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-03-27 Lei Wang, Huanyuan Shan, Lin Nie, Dezi Liu, Zhaojun Yan, Guoliang Li, Cheng Cheng, Yushan Xie, Han Qu, Wenwen Zheng, Xi Kang
We have developed a novel method for co-adding multiple under-sampled images that combines the iteratively reweighted least squares and divide-and-conquer algorithms. Our approach not only allows for the anti-aliasing of the images but also enables Point-Spread Function (PSF) deconvolution, resulting in enhanced restoration of extended sources, the highest peak signal-to-noise ratio, and reduced ringing
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Optical Transient Source AT2021lfa: A Possible “Dirty Fireball” Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-03-27 Xue-Mei Ye, Da-Ming Wei, Yi-Ming Zhu, Zhi-Ping Jin
AT2021lfa, also known as ZTF21aayokph, was detected by the Zwicky Transient Facility on 2021 May 4, at 05:34:48 UTC. Follow-up observations were conducted using a range of ground-based optical telescopes, as well as Swift/XRT and VLA instruments. AT2021lfa is classified as an “orphan afterglow” candidate due to its rapid flux decline and its reddened color (g − r = 0.17 ± 0.14 mag). For an optical
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A Study of 10 Rotating Radio Transients Using Parkes Radio Telescope Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-03-27 Xinhui Ren, Jingbo Wang, Wenming Yan, Jintao Xie, Shuangqiang Wang, Yirong Wen, Yong Xia
Rotating Radio Transients (RRATs) are a relatively new subclass of pulsars that emit detectable radio bursts sporadically. We analyzed 10 RRATs observed using the Parkes telescope, with eight of these observed via the ultra-wide-bandwidth low-frequency (UWL) receiver. We measured the burst rate and produced integrated profiles spanning multiple frequency bands for three RRATs. We also conducted a spectral
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Characteristics of Emission Non-nulling Pulsars Through Simulation Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-03-27 Rai Yuen
We investigate the population and several properties of radio pulsars whose emission does not null (non-nulling) through simulation of a large pulsar sample. Emission from a pulsar is identified as non-nulling if (i) the emission does not cease across the whole pulse profile, and (ii) the emission is detectable. For (i), we adopt a model for switching in the plasma charge density, and emission persists
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Four Late-type Galaxies with Double Radio Lobes and Properties of Such Galaxies Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-03-27 Z. S. Yuan, X. Y. Gao, Z. L. Wen, J. L. Han
The triggering mechanism for radio lobes from late-type galaxies is not fully understood. More samples are desired for a thorough investigation and statistics. By utilizing the optical data from the newly released Dark Energy Spectroscopic Instrument imaging surveys and the radio sources from the NRAO VLA Sky Survey and the Faint Images of the Radio Sky at Twenty-centimeter, we identify four Late-type
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Development of a Front End Array for Broadband Phased Array Receiver Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-03-26 Kai Wang, Liang Cao, Jun Ma, Xue-Feng Duan, Hao Yan, Mao-Zheng Chen, Yun-Wei Ning
The receiver is a signal receiving device placed at the focus of the telescope. In order to improve the observation efficiency, the concept of phased array receiver has been proposed in recent years, which places a small phased array at the focal plane of the reflector, and flexible pattern and beam scanning functions can be achieved through a beamforming network. If combined with the element multiplexing
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All-sky Guide Star Catalog for CSST Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-03-26 Hui-Mei Feng, Zi-Huang Cao, Man I Lam, Ran Li, Hao Tian, Da-Yi Yin, Yuan-Yu Yang, Xin Zhang, Dong-Wei Fan, Yi-Qiao Dong, Xin-Feng Li, Wei Wang, Long Li, Hugh R. A. Jones, Yi-Han Tao, Jia-Lu Nie, Pei-Pei Wang, Mao-Yuan Liu, He-jun Yang, Chao Liu
The China Space Station Telescope (CSST) is a two-meter space telescope with multiple back-end instruments. The Fine Guidance Sensor (FGS) is an essential subsystem of the CSST Precision Image Stability System to ensure the required absolute pointing accuracy and line-of-sight stabilization. In this study, we construct the Main Guide Star Catalog for FGS. To accomplish this, we utilize the information
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Inverse Calculation and Regularization Process for the Solar Aspect System (SAS) of HXI Payload on ASO-S Spacecraft Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-03-20 Ji-Rui Yu, Ping Ruan, Yang Su, Ying-Hong He, Jin-You Tao, Zhe Zhang, Song Guo, Bin Xue, Jian-Feng Yang
For the ASO-S/HXI payload, the accuracy of the flare reconstruction is reliant on important factors such as the alignment of the dual grating and the precise measurement of observation orientation. To guarantee optimal functionality of the instrument throughout its life cycle, the Solar Aspect System (SAS) is imperative to ensure that measurements are accurate and reliable. This is achieved by capturing
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Quantifying the Tension between Cosmological Models and JWST Red Candidate Massive Galaxies Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-03-19 Jun-Chao Wang, Zhi-Qi Huang, Lu Huang, Jianqi Liu
We develop a Python tool to estimate the tail distribution of the number of dark matter halos beyond a mass threshold and in a given volume in a light-cone. The code is based on the extended Press–Schechter model and is computationally efficient, typically taking a few seconds on a personal laptop for a given set of cosmological parameters. The high efficiency of the code allows a quick estimation
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Reflector Deformation Measurement and Correction Methodology of Large Antenna Based on Phased Array Feed Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-03-19 Zan Wang, De-Qing Kong, Hong-Bo Zhang, Yan Su, Xin-Ying Zhu, Cong-Si Wang, Yu-Chen Liu
To solve the problem of time-consuming measurement and correction of large antennas’ reflector deformation, a new microwave holography methodology based on a Phased Array Feed (PAF) is proposed. Starting from the known expression of receiving signals in microwave holography, the theory of PAF holography is derived through Geometrical Optics. Reflector deformation, as well as pointing deviation and
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Cosmological Constraints on Neutrino Masses in Light of JWST Red and Massive Candidate Galaxies Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-03-18 Jian-Qi Liu, Zhi-Qi Huang, Yan Su
The overabundance of the red and massive candidate galaxies observed by the James Webb Space Telescope (JWST) implies efficient structure formation or large star formation efficiency at high redshift z ∼ 10. In the scenario of a low or moderate star formation efficiency, because massive neutrinos tend to suppress the growth of structure of the universe, the JWST observation tightens the upper bound
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Applying Hybrid Clustering in Pulsar Candidate Sifting with Multi-modality for FAST Survey Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-03-06 Zi-Yi You, Yun-Rong Pan, Zhi Ma, Li Zhang, Shuo Xiao, Dan-Dan Zhang, Shi-Jun Dang, Ru-Shuang Zhao, Pei Wang, Ai-Jun Dong, Jia-Tao Jiang, Ji-Bing Leng, Wei-An Li, Si-Yao Li
Pulsar search is always the basis of pulsar navigation, gravitational wave detection and other research topics. Currently, the volume of pulsar candidates collected by the Five-hundred-meter Aperture Spherical radio Telescope (FAST) shows an explosive growth rate that has brought challenges for its pulsar candidate filtering system. Particularly, the multi-view heterogeneous data and class imbalance
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A Machine Learning Made Catalog of FR-II Radio Galaxies from the FIRST Survey Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-03-06 Bao-Qiang Lao, Xiao-Long Yang, Sumit Jaiswal, Prashanth Mohan, Xiao-Hui Sun, Sheng-Li Qin, Ru-Shuang Zhao
We present an independent catalog (FRIIRGcat) of 45,241 Fanaroff–Riley Type II (FR-II) radio galaxies compiled from the Very Large Array Faint Images of the Radio Sky at Twenty-centimeters (FIRST) survey and employed the deep learning method. Among them, optical and/or infrared counterparts are identified for 41,425 FR-IIs. This catalog spans luminosities 2.63 × 1022 ≤ L rad ≤ 6.76 × 1029 W Hz−1 and
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A Quick Calculation Method for Radiation Pattern of Submillimeter Telescope with Deformation and Displacement Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-03-06 Jia You, Yi-Wei Yao, Zheng Wang
Radiation pattern captures the electromagnetic performance of reflector antennas, which is significantly affected by the deformation of the primary reflector due to gravity and the displacement of the secondary reflector. During the design process of large reflector antennas, a substantial amount of time is often dedicated to iteratively adjusting structural parameters and validating electromagnetic
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EP Aquarii: A New Picture of the Circumstellar Envelope Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-03-05 Pham T. Nhung, Do T. Hoai, Pierre Darriulat, Pham Tuan-Anh, Pham N. Diep, Nguyen B. Ngoc, Tran T. Thai
New analyses of earlier ALMA observations of oxygen-rich AGB star EP Aquarii are presented, which complete a previously published analysis and offer a different interpretation of the morpho-kinematics of the circumstellar envelope. The birth of the equatorial density enhancement (EDE) is shown to occur very close to the star where evidence for rotation has been obtained. Close to the star and where
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The Influence of Velocity-dependent Correction Factor on Proton Decay Reactions in Massive White Dwarfs Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-03-04 Jing-Jing Liu, Dong-Mei Liu
Twenty-five typical massive white dwarfs (WDs) are selected and the proton decay reaction catalyzed by magnetic monopoles (MMs) for these WDs is discussed. A velocity-dependent correction factor strongly affects the cross-section. We find that a strong suppression controls the monopole catalysis of nucleon decay by the correction factor. The maximum number of MMs is captured and the luminosity can
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Ground-layer Adaptive Optics for the 2.5 m Wide-field and High-resolution Solar Telescope Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-03-04 Ying Yang, Lan-Qiang Zhang, Nan-Fei Yan, Jin-Sheng Yang, Zhen Li, Teng-Fei Song, Xue-Jun Rao, Chang-Hui Rao
The 2.5 m wide-field and high-resolution solar telescope (WeHoST) is currently under developing for solar observations. WeHoST aims to achieve high-resolution observations over a super-wide field of view (FOV) of 5′ × 5′, and a desired resolution of 0.3″. To meet the scientific requirements of WeHoST, the ground-layer adaptive optics (GLAO) with a specially designed wave front sensing system is as
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Research on Pulsar Time Steered Atomic Time Algorithm Based on DPLL Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-03-04 Ze-Hao Zheng, Yang Liu, Dan Shen, Fan Feng, Jiu-Long Liu, Yue-Xin Ma, Xiang-Wei Zhu
In today’s society, there is a wide demand for high-precision and high-stability time service in the fields of electric power, communication, transportation and finance. At present, the time standard in various countries is mainly based on atomic clocks, but the frequency drift of atomic clocks will affect the long-term stability performance. Compared with atomic clocks, millisecond pulsars have better
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Derivative Spectroscopy and its Application at Detecting the Weak Emission/Absorption Lines Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-03-04 Lihuan Yu, Jiangdan Li, Jinliang Wang, Jiajia Li, Jiao Li, Qiang Xi, Zhanwen Han
The development of spectroscopic survey telescopes like Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST), Apache Point Observatory Galactic Evolution Experiment and Sloan Digital Sky Survey has opened up unprecedented opportunities for stellar classification. Specific types of stars, such as early-type emission-line stars and those with stellar winds, can be distinguished by the profiles
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A Galaxy Image Augmentation Method Based on Few-shot Learning and Generative Adversarial Networks Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-03-04 Yiqi Yao, Jinqu Zhang, Ping Du, Shuyu Dong
Galaxy morphology classifications based on machine learning are a typical technique to handle enormous amounts of astronomical observation data, but the key challenge is how to provide enough training data for the machine learning models. Therefore this article proposes an image data augmentation method that combines few-shot learning and generative adversarial networks. The Galaxy10 DECaLs data set
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Long-term Evolution of Solar Activity and Prediction of the Following Solar Cycles Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-03-04 Pei-Xin Luo, Bao-Lin Tan
Solar activities have a great impact on modern high-tech systems, such as human aerospace activities, satellite communication and navigation, deep space exploration, and related scientific research. Therefore, studying the long-term evolution trend of solar activity and accurately predicting the future solar cycles are highly anticipated. Based on the wavelet transform and empirical function fitting
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A Comparative Study of the Power-law Relationship between the Pulse width and Energy of Precursor and Main Burst Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-02-26 Hui-Ying Deng, Zhao-Yang Peng, Jia-Ming Chen, Dan Zhu
In gamma-ray burst prompt emission, there is still no consistent conclusion if the precursor and main burst share the same origin. In this paper, we try to study this issue based on the relationship between pulse width and energy of the precursor and main burst. We systematically search the light curve data observed by Swift/BAT and Fermi/GBM, and find 13 long bursts with well-structured precursors
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Confirmation of a Sub-Saturn-size Transiting Exoplanet Orbiting a G Dwarf: TOI-1194 b and a Very Low Mass Companion Star: TOI-1251 B from TESS Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-02-26 Jia-Qi Wang, Xiao-Jun Jiang, Jie Zheng, Hanna Kellermann, Arno Riffeser, Liang Wang, Karen A. Collins, Allyson Bieryla, Lars A. Buchhave, Steve B. Howell, Elise Furlan, Eric Girardin, Joao Gregorio, Eric Jensen, Felipe Murgas, Mesut Yilmaz, Sam Quinn, Xing Gao, Ruo-Yu Zhou, Frank Grupp, Hui-Juan Wang
We report the confirmation of a sub-Saturn-size exoplanet, TOI-1194 b, with a mass of about 0.456−0.051+0.055 M J, and a very low mass companion star with a mass of about 96.5 ± 1.5 M J, TOI-1251 B. Exoplanet candidates provided by the Transiting Exoplanet Survey Satellite (TESS) are suitable for further follow-up observations by ground-based telescopes with small and medium apertures. The analysis
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A Hierarchical Method for Locating the Interferometric Fringes of Celestial Sources in the Visibility Data Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-02-26 Rong Ma, Ruiqing Yan, Hanshuai Cui, Xiaochun Cheng, Jixia Li, Fengquan Wu, Zongyao Yin, Hao Wang, Wenyi Zeng, Xianchuan Yu
In source detection in the Tianlai project, locating the interferometric fringe in visibility data accurately will influence downstream tasks drastically, such as physical parameter estimation and weak source exploration. Considering that traditional locating methods are time-consuming and supervised methods require a great quantity of expensive labeled data, in this paper, we first investigate characteristics
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Rotating Massive Strangeon Stars and X-Ray Plateau of Short GRBs Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-02-21 Xi-Yan Yang, Xiao-Yu Lai, Wei-Wei Tan, Ren-Xin Xu
Strangeon stars, which are proposed to describe the nature of pulsar-like compact stars, have passed various observational tests. The maximum mass of a non-rotating strangeon star could be high, which implies that the remnants of binary strangeon star mergers could even be long-lived massive strangeon stars. We study rigidly rotating strangeon stars in the slowly rotating approximation, using the Lennard-Jones
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The Mass Assembly History for Galaxies with MaNGA Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-02-21 Xue Ge, Hong-Tao Wang, Cheng-Long Lei, Yun-Jun Guo, Yi-Long Jiang, Xiao-Xiao Cao
How galaxies assemble masses through their own star formation or interaction with the external environment is still an important topic in the field of galaxy formation and evolution. We use Value Added Catalogs with galaxy features that are spatially and temporally resolved from Sloan Digital Sky Survey Data Release 17 to investigate the mass growth histories of early-type galaxies (ETGs) and late-type
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An Analysis of the Fragmentation of Observing Time At the Muztagh-Ata Site Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-02-20 Wen-Bo Gu, Jing Xu, Guo-Jie Feng, Xuan Zhang, Le-Tian Wang, Xin-Liang Wang, Ali Esamdin, Li-Xian Shen
Cloud cover plays a pivotal role in assessing observational conditions for astronomical site-testing. Except for the fraction of observing time, its fragmentation also wields a significant influence on the quality of nighttime sky clarity. In this article, we introduce the function Γ∈0,1 , designed to comprehensively capture both the fraction of available observing time and its continuity. Leveraging
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The Radcliffe Wave Parameters from Data on Open Star Clusters Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-02-20 V. V. Bobylev, A. T. Bajkova
A spectral analysis of the vertical positions and velocities of 374 open star clusters (OSCs) was carried out. We took these OSCs from the Hunt and Reffert catalog; they have an average age of about 10 million years, and are located on the galactic plane XY in a narrow zone inclined by 25° to the galactic axis Y. The following estimates of the parameters of the Radcliffe wave were obtained: (a) the
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Dark Matter Search in Dwarf Irregular Galaxies with Ten Years of Data from the IceCube Neutrino Observatory Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-02-20 Yi-Fei Lü, Ben-Yang Zhu, Rong-Lan Li, Xue-Kang Guo, Tian-Ci Liu, Yong-Bo Huang, Yun-Feng Liang
Dwarf irregular galaxies (dIrrs), as rotationally supported systems, have more reliable J-factor measurements than dwarf spheroidal galaxies and have received attention as targets for dark matter detection in recent years. In this paper, we use 10 yr of IceCube muon-track data and an unbinned maximum-likelihood-ratio method to search for neutrino signals beyond the background from the directions of
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Gamma/Hadron Separation Method for the HADAR Experiment Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-02-20 Yang-Zhao Ren, Tian-Lu Chen, You-Liang Feng, Dan-Zeng Luo-Bu, Yi-Qing Guo, Cheng Liu, Qi Gao, Mao-Yuan Liu, Xiang-Li Qian, Ya-Ping Wang, Zi-Hao Zhang, Xin-Long Li, Qing-Yuan Hou, Heng-Jiao Liu, Qing-Qian Zhou, Shan-Jie Shu
Ground-based arrays of imaging atmospheric Cherenkov telescopes (IACTs) are the most sensitive γ-ray detectors for energies of approximately 100 GeV and above. One such IACT is the High Altitude Detection of Astronomical Radiation (HADAR) experiment, which uses a large aperture refractive water lens system to capture atmospheric Cherenkov photons (i.e., the imaging atmospheric Cherenkov technique)
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Large-aperture Telescope Tracking Control Based on Time-synchronization Strategy Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-02-20 Yun Li, Yu Ye, Shi-Hai Yang, Ling-Zhe Xu, Jin Xu, Hai Wang, Zhuang-Zhuang Deng, Rui-Qiang Liu, Xiao-Jie Gu, Bo-Zhong Gu
A time-synchronization strategy for packetized transmission of target position about a large-aperture telescope observation control system has been proposed in this study. Compared with the existing telescope tracking strategy, the target position packing and sending strategy based on the time synchronization method proposed in this paper has the advantages of high stability and reliability. First
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Comparing the Structural Parameters of the Milky Way to Other Spiral Galaxies Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-02-20 Jacob A. Guerrette, Aleksandr V. Mosenkov, Dallin Spencer, Zacory D. Shakespear
The structural parameters of a galaxy can be used to gain insight into its formation and evolution history. In this paper, we strive to compare the Milky Way’s structural parameters to other, primarily edge-on, spiral galaxies in order to determine how our Galaxy measures up to the Local Universe. For our comparison, we use the galaxy structural parameters gathered from a variety of literature sources
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Study of Type-B QPOs Observed in Black Hole X-Ray Binary Swift J1728.9-3613 Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-02-20 Raj Kumar
We report the detection of type-B quasi-periodic oscillation (QPO) of the black hole X-ray binary Swift J1728.9-3613 observed by NICER during the 2019 outburst. A type-B QPO was observed for the first two days and it disappeared as flux increased, but again appeared at ∼7.70 Hz when flux was dramatically decreased. The source was found in the soft intermediate state during these observations. We further
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The Impact of Bias Row Noise to Photometric Accuracy: Case Study Based on a Scientific CMOS Detector Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-02-08 Li Shao, Hu Zhan, Chao Liu, Haonan Chi, Qiuyan Luo, Huaipu Mu, Wenzhong Shi
We tested a new model of CMOS detector manufactured by the Gpixel Inc, for potential space astronomical application. In laboratory, we obtain some bias images under the typical application environment. In these bias images, clear random row noise pattern is observed. The row noise also contains some characteristic spatial frequencies. We quantitatively estimated the impact of this feature to photometric
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A New Method for Monitoring Scattered Stray Light of an Inner-occulted Coronagraph Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-02-07 Da-Yang Liu, Hong-Xin Zhang, Ming-Zhe Sun, Zheng-Hua Huang, Li-Dong Xia, Wei-Xin Liu, Hui Fu
The scattered stray light of a coronagraph is a type of stray light that is generated by the objective lens as its surface defects are irradiated by sunlight. The defects mainly include dust and blemishes on the lens surface, microroughness of the lens surface, and impurity and inhomogeneity of the glass. Unlike the other types of relatively stable defects introduced when the objective lens is being
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GRB 200612A: An Ultralong Gamma-Ray Burst Powered by Magnetar Spinning Down Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-02-07 Liang-Jun Chen, Xiang-Gao Wang, De-Long Yang, En-Wei Liang
GRB 200612A could be classified as an ultralong gamma-ray burst due to its prompt emission lasting up to ∼1020 s and the true timescale of the central engine activity t burst ≥ 4 × 104 s. The late X-ray light curve with a decay index of α = 7.53 is steeper than the steepest possible decay from an external shock model. We propose that this X-ray afterglow can be driven by dipolar radiation from the
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The Precursor of GRB211211A: A Tide-induced Giant Quake? Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-02-07 Enping Zhou, Yong Gao, Yurui Zhou, Xiaoyu Lai, Lijing Shao, Weiyang Wang, Shaolin Xiong, Renxin Xu, Shuxu Yi, Garvin Yim, Han Yue, Zhen Zhang
The equilibrium configuration of a solid strange star in the final inspiral phase with another compact object is generally discussed, and the starquake-related issue is revisited, for a special purpose to understand the precursor emission of binary compact star merger events (e.g., that of GRB211211A). As the binary system inspirals inward due to gravitational wave radiation, the ellipticity of the
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Lobe-dominated γ-Ray Emission of Compact Symmetric Objects Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-02-07 Ying-Ying Gan, Hai-Ming Zhang, Xing Yang, Ying Gu, Jin Zhang
The γ-ray emitting compact symmetric objects (CSOs) PKS 1718–649, NGC 3894, and TXS 0128+554 are lobe-dominated in the radio emission. In order to investigate their γ-ray radiation properties, we analyze the ∼14 yr Fermi/LAT observation data of the three CSOs. They all show the low luminosity (1041–1043 erg s−1) and no significant variability in the γ-ray band. Their γ-ray average spectra can be well
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The ALMA-QUARKS Survey. I. Survey Description and Data Reduction Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-02-02 Xunchuan Liu, Tie Liu, Lei Zhu, Guido Garay, Hong-Li Liu, Paul Goldsmith, Neal Evans, Kee-Tae Kim, Sheng-Yuan Liu, Fengwei Xu, Xing Lu, Anandmayee Tej, Xiaofeng Mai, Leonardo Bronfman, Shanghuo Li, Diego Mardones, Amelia Stutz, Ken’ichi Tatematsu, Ke Wang, Qizhou Zhang, Sheng-Li Qin, Jianwen Zhou, Qiuyi Luo, Siju Zhang, Yu Cheng, Jinhua He, Qilao Gu, Ziyang Li, Zhenying Zhang, Suinan Zhang, Anindya
This paper presents an overview of the QUARKS survey, which stands for “Querying Underlying mechanisms of massive star formation with ALMA-Resolved gas Kinematics and Structures.” The QUARKS survey is observing 139 massive clumps covered by 156 pointings at Atacama Large Millimeter/submillimeter Array (ALMA) Band 6 (λ ∼ 1.3 mm). In conjunction with data obtained from the ALMA-ATOMS survey at Band 3
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The Clumpy Structure of Five Star-bursting Dwarf Galaxies in the MaNGA Survey Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-01-31 Mengting Ju, Jun Yin, Lei Hao, Chenxu Liu, Chao-Wei Tsai, Junfeng Wang, Zhengyi Shao, Shuai Feng, Yu Rong
The star-forming clumps in star-bursting dwarf galaxies provide valuable insights into understanding the evolution of dwarf galaxies. In this paper, we focus on five star-bursting dwarf galaxies featuring off-centered clumps in the Mapping Nearby Galaxies at Apache Point Observatory survey. Using the stellar population synthesis software Fitting Analysis using Differential evolution Optimization, we
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Dreicer Electric Field Definition and Runaway Electrons in Solar Flares Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-01-31 Yu. T. Tsap, A. V. Stepanov, Yu. G. Kopylova
We analyze electron acceleration by a large-scale electric field E in a collisional hydrogen plasma under the solar flare coronal conditions based on approaches proposed by Dreicer and Spitzer for the dynamic friction force of electrons. The Dreicer electric field E Dr is determined as a critical electric field at which the entire electron population runs away. Two regimes of strong (E ≲ E Dr) and
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Relations between the Fractional Variation of the Ionizing Continuum and C iv Broad Absorption Lines with Different Ionization Levels Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-01-31 Ying-Ru Lin, Cai-Juan Pan, Wei-Jian Lu
This paper explores the correlation between the fractional variation of the ionizing continuum and C iv broad absorption lines (BALs) with different ionization levels. Our results reveal anti-correlations between fractional variation of the continuum and fractional equivalency width (EW) variation of the C iv BALs without Al iii BAL/mini-BALs at corresponding velocities, providing evidence for the
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Electromagnetic Ion Beam Instability in the Solar Corona Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-01-31 Wen Liu, Jin-Song Zhao, De-Jin Wu, Huan-Yu Jia, Si-Ming Liu
Remote-sensing measurements indicate that heavy ions in the corona undergo an anisotropic and mass-charge dependent energization. A popular explanation to this phenomenon is the damping of the Alfvén/ion cyclotron waves. In this paper, we propose that the ion beam instability can be an important source of the Alfvén/ion cyclotron waves, and we study the excitation of the ion beam instability in the
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Analysis of Bright Source Hardness Ratios in the 4 yr Insight-HXMT Galactic Plane Scanning Survey Catalog Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-01-31 Chen Wang, Jin-Yuan Liao, Ju Guan, Yuan Liu, Cheng-Kui Li, Na Sai, Jing Jin, Shuang-Nan Zhang
We conduct a statistical analysis of the hardness ratio (HR) for bright sources in the 4 yr Galactic Plane Scanning Survey catalog of Insight-HXMT. Depending on the stable (variable) flux F s (F v) or spectrum S s(S v) of each source, the bright sources are classified into three groups: F v&S v, F v&S s, and F s&S s. Our study of the HR characteristics in different types of sources reveals that accretion-powered
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Variation in the Flaring Potential of Different Sunspot Groups During Different Phases of Solar Cycles 23 and 24 Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-01-31 Abha Singh, Anurag Chaudhari, Gyaneshwar Sharma, A. K. Singh
In this present study, we have analyzed different types of X-ray solar flares (C, M, and X classes) coming out from different classes of sunspot groups (SSGs). The data which we have taken under this study cover the duration of 24 yr from 1996 to 2019. During this, we observed a total of 15015 flares (8417 in SC-23 and 6598 in SC-24) emitted from a total of 33780 active regions (21746 in SC-23 and
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Free Energy of Anisotropic Strangeon Stars Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-01-31 Shichuan Chen, Yong Gao, Enping Zhou, Renxin Xu
Can pulsar-like compact objects release further huge free energy besides the kinematic energy of rotation? This is actually relevant to the equation of state of cold supra-nuclear matter, which is still under hot debate. Enormous energy is surely needed to understand various observations, such as γ-ray bursts, fast radio bursts and soft γ-ray repeaters. In this paper, the elastic/gravitational free
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Variable Stars in the 50BiN Open Cluster Survey. III. NGC 884 Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-01-31 Lin-Hong Wang, Qian-Heng Nie, Kun Wang, Xiao-Dian Chen, Chun-Guang Zhang, Li-Cai Deng, Xiao-Bin Zhang, Tian-Lu Chen
Open clusters are the basic building blocks that serve as a laboratory for the study of young stellar populations in the Milky Way. Variable stars in open clusters provide a unique way to accurately probe the internal structure, temporal and dynamical evolutionary stages of individual stars and the host cluster. The most powerful tool for such studies is time-domain photometric observations. This paper
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Period–Luminosity Relationship for δ Scuti Stars Revisited Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-01-31 Atila Poro, S. Javad Jafarzadeh, Roghaye Harzandjadidi, Mohammad Madani, Elnaz Bozorgzadeh, Esfandiar Jahangiri, Ahmad Sarostad, Ailar Alizadehsabegh, Maryam Hadizadeh, Mohammad EsmaeiliVakilabadi
The Gaia DR3 parallax approach was used to estimate the absolute parameters of 2375 δ Scuti stars from the ASAS catalog. The selected stars have a variety of observational characteristics, with a higher than 80% probability of being δ Scuti stars. We have displayed all the stars in the Hertzsprung–Russell diagram along with the δ Scuti instability strip, the Zero Age Main Sequence and the Terminal
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Data-driven Simulations of Magnetic Field Evolution in Active Region 11429: Magneto-frictional Method Using PENCIL CODE Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-01-31 P. Vemareddy, Jörn Warnecke, Ph. A. Bourdin
Coronal magnetic fields evolve quasi-statically over long timescales and dynamically over short timescales. As of now there exist no regular measurements of coronal magnetic fields, and therefore generating the coronal magnetic field evolution using observations of the magnetic field at the photosphere is a fundamental requirement to understanding the origin of transient phenomena from solar active
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Dealing with the Data Imbalance Problem in Pulsar Candidate Sifting Based on Feature Selection Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-01-24 Haitao Lin, Xiangru Li
Pulsar detection has become an active research topic in radio astronomy recently. One of the essential procedures for pulsar detection is pulsar candidate sifting (PCS), a procedure for identifying potential pulsar signals in a survey. However, pulsar candidates are always class-imbalanced, as most candidates are non-pulsars such as RFI and only a tiny part of them are from real pulsars. Class imbalance
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Time-resolved Spectral Properties of Fermi-GBM Bright Long Gamma-Ray Bursts Res. Astron. Astrophys. (IF 1.8) Pub Date : 2024-01-23 Wan-Kai Wang, Wei Xie, Zhi-Fu Gao, Shuo Xiao, Ai-Jun Dong, Bin Zhang, Qi-Jun Zhi
The prompt emission mechanism of gamma-ray bursts (GRBs) is still unclear, and the time-resolved spectral analysis of GRBs is a powerful tool for studying their underlying physical processes. We performed a detailed time-resolved spectral analysis of 78 bright long GRB samples detected by Fermi/Gamma-ray Burst Monitor. A total of 1490 spectra were obtained and their properties were studied using a