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Radiative capture of proton through the ^(14)N(p,γ)^(15)O reaction at low energy

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Chinese Physics C 2024年第4期48卷 183-192页

作者： B.F.Irgaziev Abdul Kabir Jameel-Un Nabi National University of Uzbekistan Tashkent 100174Uzbekistan space and astrophysics research lab National Centre of GIS and Space ApplicationsDepartment of Space ScienceInstitute of Space TechnologyIslamabad 44000Pakistan University of Wah Quaid AvenueWah Cantt 47040PunjabPakistan

The CNO cycle is the main source of energy in stars more massive than our *** process defines the energy production,the duration of which can be used to determine the lifetime of massive *** cycle is an important tool for determining the age of globular *** proton capture via p+^(14)N→^(15)O+γ,at energies of astrophysical interest,is an important process in the CNO *** this project,we apply a potential model to describe both non-resonant and resonant reactions in the channels where radiative capture occurs through electric E1 *** employed the R-matrix method to describe the ongoing reactions via M1 resonant transitions,when it was not possible to correctly reproduce the experimental data using the potential *** partial components of the astrophysical S-factor are calculated for all possible electric and magnetic dipole transitions in ^(15)*** linear extrapolated S-factor at zero energy(S(0))agrees well with earlier reported values for all transition types considered in this *** on the value of the total astrophysical S-factor,depending on the collision energy,we calculate the nuclear reaction rates for p+^(14)N→^(15)O+γ.The computed rates agree well with the results reported in the NACRE II Collaboration and most recent existing measurements.

关键词： CNO cycle potential model R-matrix method cross-section astrophysical S-factor nuclear rates.

On the Relation Between Symmetry of Radio Galaxies and Their Physical Parameters

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research in Astronomy and astrophysics 2024年第9期24卷 39-61页

作者： Mohsen Javaherian Halime Miraghaei Hooman Moradpour research institute for Astronomy and astrophysics of Maragha (RIAAM) University of Maragheh

Gravity as a fundamental force plays a dominant role in the formation and evolution of cosmic objects and leaves its effect in the emergence of symmetric and asymmetric structures. Thus, analyzing the symmetry criteria allows us to uncover mechanisms behind the gravity interaction and understand the underlying physical processes that contribute to the formation of large-scale structures such as galaxies. We use a segmentation process using intensity thresholding and the k-means clustering algorithm to analyze radio galaxy images. We employ a symmetry criterion and explore the relation between morphological symmetry in radio maps and host galaxy properties. Optical properties(stellar mass, black hole mass, optical size(R50), concentration, stellar mass surface density(μ50), and stellar age) and radio properties（radio flux density, radio luminosity, and radio size） are considered. We found that there is a correlation between symmetry and radio size, indicating larger radio sources have smaller symmetry indices. Therefore, size of radio sources should be considered in any investigation of symmetry. Weak correlations are also observed with other properties, such as R50for FRI galaxies and stellar *** compare the symmetry differences between FRI and FRII radio galaxies. FRII galaxies show higher symmetry in 1.4 GHz and 150 MHz maps. Investigating the influence of radio source sizes, we discovered that this result is independent of the sizes of radio sources. These findings contribute to our understanding of the morphological properties and analyses of radio galaxies.

关键词： catalogs galaxies: distances and redshifts galaxies: nuclei methods: data analysis techniques: image processing

Scintillation Arc from FRB 20220912A

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Science China(Physics,Mechanics & Astronomy) 2024年第1期67卷 134-142页

作者： Zi-Wei Wu Robert AMain Wei-Wei Zhu Bing Zhang Peng Jiang Jia-Rui Niu Jin-Lin Han Di Li Ke-Jia Lee Dong-Zi Li Yuan-Pei Yang Fa-Yin Wang Rui Luo Pei Wang Chen-Hui Niu Heng Xu Bo-Jun Wang Wei-Yang Wang Yong-Kun Zhang Yi Feng De-Jiang Zhou Yong-Hua Xu Can-Min Deng Yu-Hao Zhu National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China Max-Planck-Institut für Radioastronomie Bonn 53121Germany institute for Frontier in Astronomy and astrophysics Beijing Normal UniversityBeijing 102206China Nevada Center for astrophysics and Department of Physics and Astronomy University of NevadaLas VegasNV 89154USA CAS Key Laboratory of FAST National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Astronomy University of Chinese Academy of SciencesBeijing 100049China NAOC-UKZN Computational astrophysics Centre University of KwaZulu-NatalDurban 4000South Africa Department of Astronomy Peking UniversityBeijing 100871China kavli institute for Astronomy and astrophysics Peking UniversityBeijing 100871China Cahill Center for Astronomy and astrophysics California Institute of TechnologyPasadena 91125USA South-Western institute For Astronomy research Yunnan UniversityKunming 650504China School of Astronomy and space Science Nanjing UniversityNanjing 210093China Key Laboratory of Modern Astronomy and astrophysics(Nanjing University) Ministry of EducationNanjing 210023China CSIRO space and Astronomy Epping 1710Australia Department of Astronomy School of Physics and Materials ScienceGuangzhou UniversityGuangzhou 510006China research Center for Intelligent Computing Platforms Zhejiang LaboratoryHangzhou 311100China Yunnan Observatories Chinese Academy of SciencesKunming 650011China Guangxi Key Laboratory for Relativistic astrophysics Department of PhysicsGuangxi UniversityNanning 530004China

We present the interstellar scintillation analysis of fast radio burst(FRB)20220912A during its extremely active episode in 2022using data from the Five-hundred-meter Aperture Spherical Radio Telescope(FAST).We detect a scintillation arc in the FRB’s secondary spectrum,which describes the power in terms of the scattered FRB signals’time delay and Doppler *** arc indicates that the scintillation is caused by a highly localized *** analysis favors a Milky Way origin of the ionized interstellar medium(IISM)for the localized scattering medium but cannot rule out a host galaxy *** present our method for detecting the scintillation arc,which can be applied generally to sources with irregularly spaced bursts or *** methods could help shed light on the complex interstellar environment surrounding the FRBs and in our Galaxy.

关键词： fast radio burst scintillation FRB 20220912A

Capture Efficiency Analysis in the Circular Restricted Three-body Problem

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research in Astronomy and astrophysics 2024年第5期24卷 198-210页

作者： Yu-Xuan Miao Xi-Yun Hou Department of Astronomy and space Science Nanjing UniversityNanjing 210023China institute of space Environment and Astrodynamics Nanjing UniversityNanjing 210023China Key Laboratory of Modern Astronomy and astrophysics Ministry of EducationNanjing 210023China

Temporary capture efficiency is studied in the framework of the circular restricted three-body problem in two ***, a non-uniform distribution of test particles around the secondary's orbit is obtained by fully accounting the secondary's gravitational influence. Second, the capture efficiency is computed based on the non-uniform distribution. Several factors influencing the result are discussed. By studying the capture efficiency in the circular restricted three-body problem of different mass ratios, a power-law relation between the capture efficiency(p) and the mass ratio(μ) is established, which is given by p ≈ 0.27 × μ^(0.53), within the range of 3.0035 ×10^(-6)≤ μ ≤ 3.0034 × 10^(-5). Taking the Sun–Earth system as an example, the influence from the orbit eccentricity of the secondary on the non-uniform distribution and the capture efficiency is studied. Our studies find that the secondary's orbit eccentricity has a negative influence on the capture efficiency.

关键词： methods numerical-celestial mechanics-planets and satellites dynamical evolution and stability

Forecasting supernova observations with the CSST:I. Photometric samples

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Science China(Physics,Mechanics & Astronomy) 2024年第11期Mechanics & Astronomy) .卷 168-181页

作者： Chengqi Liu Youhua Xu Xianmin Meng Xin Zhang Shi-Yu Li Yuming Fu Xiaofeng Wang Shufei Liu Zun Luo Guanghuan Wang Hu Zhan Department of Astronomy School of Physics Peking University kavli institute for Astronomy and astrophysics Peking University Key Laboratory of space Astronomy and Technology National Astronomical ObservatoriesChinese Academy of Sciences Beijing Planetarium Beijing Academy of Science and Technology Leiden Observatory Leiden University Kapteyn Astronomical institute University of Groningen Physics Department Tsinghua University School of Astronomy and space Science University of Chinese Academy of Sciences

The China space Station Telescope（CSST, also known as Xuntian） is a serviceable two-meter-aperture wide-field telescope operating in the same orbit as the China space Station. The CSST plans to survey a sky area of 17,500 deg2of the medium-to-high Galactic latitude to a depth of 25-26 AB mag in at least 6 photometric bands over 255-1,000 nm. Within such a large sky area,slitless spectra will also be taken over the same wavelength range as the imaging survey. Even though the CSST survey is not dedicated to time-domain studies, it would still detect a large number of transients, such as supernovae（SNe）. In this paper, we simulate photometric SN observations based on a strawman survey plan using the Sncosmo package. During its 10-year survey,the CSST is expected to observe about 5 million SNe of various types. With quality cuts, we obtain a “gold” sample that comprises roughly 7,400 SNe Ia, 2,200 SNe Ibc, and 6,500 SNe Ⅱ candidates with correctly classified percentages reaching 91%,63%, and 93%（formally defined as classification precision）, respectively. The same survey can also trigger alerts for the detection of about 15,500 SNe Ia（precision 61%） and 2,100 SNe Ⅱ（precision 49%） candidates at least two days before the light ***, the near-ultraviolet observations of the CSST will be able to catch hundreds of shock-cooling events serendipitously every year. These results demonstrate that the CSST can make a potentially significant contribution to SN studies.

关键词： space-based ultraviolet optical and infrared telescopes supernovae data analysis

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On the Performances of Estimating Stellar Atmospheric Parameters from CSST Broad-band Photometry

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research in Astronomy and astrophysics 2024年第4期24卷 161-173页

作者： Rui-Feng Shi Yang Huang Xin-Yi Li Hua-Wei Zhang School of Astronomy and space Science University of Chinese Academy of SciencesBeijing 100049China South-Western institute for Astronomy research Yunnan UniversityKunming 650500China CAS Key Lab of Optical Astronomy Key Laboratory of Space Astronomy and TechnologyNational Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China College of Physics and Electronic Engineering Qilu Normal UniversityJinan 250200China Department of Astronomy School of PhysicsPeking UniversityBeijing 100871China kavli institute for Astronomy and astrophysics Peking UniversityBeijing 100871China

Deriving atmospheric parameters of a large sample of stars is of vital importance to understand the formation and evolution of the Milky *** surveys,especially those with near-ultraviolet filters,can offer accurate measurements of stellar parameters,with the precision comparable to that from low/medium resolution *** this study,we explore the capability of measuring stellar atmospheric parameters from Chinese space Station Telescope(CSST)broad-band photometry(particularly in the near-ultraviolet bands),based on synthetic colors derived from model *** find that colors from the optical and near-ultraviolet filter systems adopted by CSST show significant sensitivities to the stellar atmospheric parameters,especially the *** to our mock data tests,the precision of the photometric metallicity is quite high,with typical values of0.17 and 0.20 dex for dwarf and giant stars,*** precision of the effective temperature estimated from broad-band colors are within 50 K.

关键词： methods:data analysis stars:abundances surveys

Acceleration of solar wind particles due to inertial Alfvén waves

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Communications in Theoretical Physics 2024年第6期76卷 137-141页

作者： Kiran Batool Imran A Khan M Shamir Abdul Kabir S Ayaz Theoretical Physics Department National Centre for PhysicsIslamabad 44000Pakistan Department of space Sciences Institute of Space TechnologyIslamabad 44000Pakistan space and astrophysics research Lab(SARL) National Center of GIS and Space Applications(NCGSA)Islamabad 44000Pakistan Salam Chair Department of PhysicsGC University LahoreKatchery RoadLahorePunjab 54000Pakistan Department of space Science and CSPAR University of Alabama in HuntsvilleHuntsvilleAL 35899United States of America

Gaining an understanding of the effects and dynamics of the solar wind is crucial for the study of space weather,Earth's magnetosphere,spacecraft protection,the dynamics of the Solar System,and various other *** show that Alfvén waves effectively transfer energy to resonant *** study demonstrates how inertial Alfvén waves deliver their energy to resonant plasma particles in different solar environments under certain *** analysis shows that inertial Alfvén waves experience more rapid damping with increasing parallel wavenumber,ambient magnetic field strength,and particle number density,coupled with a decrease in *** rate of energy transfer to resonant particles intensifies with higher temperatures and reduced parallel wavenumber and particle number *** with higher initial velocities actively participate in Landau damping,especially in regions with a stronger ambient magnetic field.

关键词： solar wind inertial Alfven waves resonant particles

HiFAST:An HIdata calibration and imaging pipeline for FAST

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Science China(Physics,Mechanics & Astronomy) 2024年第5期67卷 182-199页

作者： Yingjie Jing Jie Wang Chen Xu Ziming Liu Qingze Chen Tiantian Liang Jinlong Xu Yixian Cao Jing Wang Huijie Hu Chuan-Peng Zhang Qi Guo Liang Gao Mei Ai Hengqian Gan Xuyang Gao Jinlin Han Ligang Hou Zhipeng Hou Peng Jiang Xu Kong Fujia Li Zerui Liu Li Shao Hengxing Pan Jun Pan Lei Qian Jinghai Sun Ningyu Tang Qingliang Yang Bo Zhang Zhiyu Zhang Ming Zhu National Astronomical Observatories Chinese Academy of SciencesBeijing 100012China institute for Frontiers in Astronomy and astrophysics Beijing Normal UniversityBeijing 02206China School of Astronomy and space Science University of Chinese Academy of SciencesBeijing 100049China Guizhou Radio Astronomical Observatory Guizhou UniversityGuiyang 55000China Max Planck institute for Extraterrestrial Physics Garching 85748Germany kavli institute for Astronomy and astrophysics Peking UniversityBeijing 100871China institute of Computational Cosmology Department of PhysicsUniversity of DurhamDurham DHI 3LEUK CAS Key Laboratory of FAST National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Deep space Exploration Laboratory/Department of Astronomy University of Science and Technology of ChinaHefei 230026China School of Astronomy and space Science University of Science and Technology of ChinaHefei 230026China astrophysics Department of PhysicsUniversity of OxfordOxford OX/3RHUK College of Earth Sciences Guilin University of TechnologyGuilin 541004China Department of Physics Anhui Normal UniversityWuhu 241002China School of Astronomy and space Science Nanjing UniversityNanjing 210023China Key Laboratory of Modern Astronomy and astrophysics Nanjing UniversityNanjing 20023China

The Five-hundred-meter Aperture Spherical radio Telescope(FAST)has the largest aperture and a 19-beam L-band receiver,making it powerful for investigating the neutral hydrogen atomic gas(HI)in the *** present HiFAST(https://***),a dedicated,modular,and self-contained calibration and imaging pipeline for processing the H?data of *** pipeline consists of frequency-dependent noise diode calibration,baseline fitting,standing wave removal using an FFT-based method,flux density calibration,stray radiation correction,and gridding to produce data *** modules can be combined as needed to process the data from most FAST observation modes:tracking,drift scanning,On-The-Fly mapping,and most of their *** HiFAST,the root-mean-square(RMS)noises of the calibrated spectra from all 19 beams were only slightly(~5%)higher than the theoretical *** results for the extended source M33 and the point sources are consistent with the results from *** moment maps(0,1 and 2)of M33 agree well with the results from the Arecibo Galaxy Environment Survey(AGES)with a fractional difference of less than 10%.For a common sample of 221 sources with signal-to-noise ratio S/N>10 from the Arecibo Legacy Fast ALFA(ALFALFA)survey,the mean value of fractional difference in the integrated flux density,Sint,between the two datasets is approximately 0.005%,with a dispersion of 15.4%.Further checks on the integrated flux density of 23 sources with seven observations indicate that the variance in the flux density of the source with luminous objects(Sint>2.5 Jy km s-1)is less than 5%.Our tests suggest that the FAST telescope,with the efficient,precise,and user-friendly pipeline HiFAST,will yield numerous significant scientific findings in the investigation of the H?in the universe.

关键词： fractional luminous correction

Intermediate-mass black holes in Green pea galaxies(IMBH-GP) I:A candidate sample from LAMOST and SDSS

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Science China(Physics,Mechanics & Astronomy) 2024年第10期Mechanics & Astronomy) .卷 151-165页

作者： Ruqiu Lin Zhen-Ya Zheng Fang-Ting Yuan Jun-Xian Wang Chunyan Jiang Ning Jiang Lingzhi Wang Linhua Jiang Xiang Ji Shuairu Zhu Xiaodan Fu Key Laboratory for research in Galaxies and Cosmology Shanghai Astronomical ObservatoryChinese Academy of Sciences School of Astronomy and space Sciences University of Chinese Academy of Sciences CAS Key Laboratory for research in Galaxies and Cosmology Department of AstronomyUniversity of Science and Technology of China Chinese Academy of Sciences South America Center for Astronomy (CASSACA) National Astronomical ObservatoriesChinese Academy of Sciences CAS Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of Sciences kavli institute for Astronomy and astrophysics Peking University Department of Astronomy School of PhysicsPeking University

The scaling relation of central massive black holes（MBHs） and their host galaxies is well-studied for supermassive BHs(SMBHs,MBH≥10～6M⊙).However,this relation has large uncertainties in the mass range of the intermediate-mass BHs(IMBHs,MBH～10～3-10～6M⊙).Since Green pea（GP） galaxies are luminous compact dwarf galaxies,which may be likely to host less massive SMBHs or even IMBHs,we systematically search for MBHs in a large sample of 2190 GP galaxies at z<0.4,selected from LAMOST and SDSS spectroscopic ***,we report a newly discovered sample of 59 MBH candidates with broad Hα *** sample has a median stellar mass of 108.83±0.11M⊙and hosts MBHs with single-epoch virial masses ranging from MBH～104.7to 108.5M⊙(median 105.85±0.64M⊙).Among the 59 MBH candidates,36 have black hole masses MBH≤10～6M⊙（IMBH candidates）,one of which even has MBH■10～5M⊙.We find that the MBH-M*relation of our MBH sample is consistent with the MBH-Mbulgerelation for SMBHs,while is above the MBH-M*relation for MBHs in dwarf galaxies in the same mass ***,we show that 25 MBH candidates,including 4 IMBH candidates,have additional evidence of black hole activities,assessed through various methods such as the broad-line width,BPT diagram,mid-infrared color,X-ray luminosity,and radio *** studies show that it is very promising to find IMBHs in GP galaxies,and the BH sample so obtained enables us to probe the connection between the MBHs and compact dwarf galaxies in the low-redshift Universe.

关键词： SMBHs IMBHs Green pea galaxies compact dwarf galaxies

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