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The Astrometric Performance of the China space Station Telescope(CSST) Sky Survey in Extending the Gaia Celestial Reference Frame

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Research in astronomy and Astrophysics 2024年第8期24卷 135-142页

作者： Jun Yao Jia-Cheng Liu Niu Liu Zi Zhu Zhen-Wei Wang school of astronomy and space science Key Laboratory of Modern Astronomy and Astrophysics (Ministry of Education)Nanjing University University of Chinese Academy of sciences

The multi-color imaging sky survey conducted by the China space Station Telescope (CSST) holds significant promise for advancing the development of the celestial reference *** this study,we focus on assessing the astrometric performance of the CSST celestial reference frame (CSST-CRF) in extending the Gaia Celestial Reference Frame 3 (Gaia-CRF3).First,the orientation precision of the CSST reference frame is evaluated using a simulated set of extragalactic sources with CSST g magnitudes ranging from 18 to 25 *** estimated orientation uncertainty caused by random error insignificantly affects the alignment between Gaia-CRF3 and the ***,the systematic effect of incomplete CSST sky coverage on the alignment between CSST-CRF and Gaia-CRF3 is discussed by analyzing the differences between the subset of Gaia-CRF3 in the CSST observation region (Gaia-CRF3′) and Gaia-CRF3 as a *** the third International Celestial Reference Frame (ICRF3) S/X band as an intermediate reference frame,the orientation offset between Gaia-CRF3′and GaiaCRF3 is estimated to be 20μ*** offset is marginally larger than the orientation offset between Gaia-CRF3 and the ICRF3,approximately 15μ*** residual spin and glide rate of Gaia-CRF3′are derived from the proper motions,consistent with that of Gaia-CRF3 within the formal ***,we explore the role of CSST in establishing a multi-band celestial reference frame by comparing its limiting magnitude and observation accuracy with existing catalogs in the infrared and ultraviolet *** to its broad wavelength coverage and highprecision measurements,CSST is well-positioned to make significant contributions to the development of a multiband celestial reference frame.

关键词： astrometry reference systems surveys

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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

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Optical system for extremely large spectroscopic survey telescope

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science China(Physics,Mechanics & astronomy) 2024年第7期67卷 158-174页

作者： Ding-qiang Su Hua Bai Xiangyan Yuan Xiangqun Cui key laboratory of the ministry of education School of Astronomy and Space ScienceNanjing UniversityNanjing 210023China Nanjing Institute of Astronomical Optics and Technology(NIAOT) Chinese Academy of SciencesNanjing 210042China University of Chinese Academy of sciences Nanjing 211135China school of astronomy and space science University of Chinese Academy of SciencesBeijing 101408China

This article presents research work on a spectroscopic survey *** idea is as follows:for such a telescope,a pure reflecting optical system is designed,which should have an aperture and a field of view(FOV)both as large as possible and excellent image quality,and then a strip lensm(lens-prism)atmospheric dispersion corrector(S-ADC)is added,only for correcting the atmospheric *** the fund limitation and the simplicity of scaling up,some 12-m telescopes are designed as ***,Korsch,and Meinel put forward the four-mirror Nasmyth systems I and II,which are used in this *** of 1.5°,2°,and 2.5°are *** all systems,the image qualities are *** the S-ADC relaxes the optical glass size restriction,this 12-m telescope with a FOV of 2.5°can be magnified in proportion to a 16-m *** etendue(from Frenchétendue)and focal surface will now be the largest in the *** such a telescope,a pure reflecting optical system can also be obtained.A subsequent coudésystem is designed with excellent image quality.

关键词： telescopes spectroscopic survey

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Mid-infrared Period–Luminosity Relations of Gaia DR3 Long Period Variables

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Research in astronomy and Astrophysics 2024年第7期24卷 59-73页

作者： Xiaohan Chen Xiaodian Chen Licai Deng Shu Wang Tianlu Chen Department of Physics College of ScienceTibet University key laboratory of Cosmic Rays (Tibet University) Ministry of Education CAS key laboratory of Optical astronomy National Astronomical ObservatoriesChinese Academy of Sciences school of astronomy and space science University of the Chinese Academy of Sciences Department of astronomy China West Normal University Institute for Frontiers in astronomy and Astrophysics Beijing Normal University

Long period variable（LPV） stars are very promising distance indicators in the infrared bands. We selected asymptotic giant branch（AGB） stars in the Large and Small Magellanic Cloud（LMC and SMC） from the Gaia Data Release 3 LPV catalog, and classified them into oxygen-rich（O-rich） and carbon-rich（C-rich） AGB *** the Wide-field Infrared Survey Explorer database, we determined the W1-and W2-band period–luminosity relations（PLRs） for each pulsation-mode sequence of AGB stars. The dispersion of the PLRs of O-rich AGB stars in sequences C' and C is relatively small, around 0.14 mag. The PLRs of LMC and SMC are consistent in each sequence. In the W2 band, the PLR of large-amplitude C-rich AGB stars is steeper than that of small-amplitude C-rich AGB stars, due to their more circumstellar dust. By two methods, we find that some PLR sequences of O-rich AGB stars in the LMC are dependent on metallicity. The coefficients of the metallicity effect are β = –0.533 ± 0.213 mag dex1and β = –0.767 ± 0.158 mag dex1for sequence C in W1 and W2 bands, respectively. The significance of the metallicity effect in W1 band for the four sequences is 2.2-3.5σ. Both of these imply that distance measurements using O-rich Mira may need to take the metallicity effect into account.

关键词： infrared: stars stars: distances stars: variables: general

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Simultaneous detection of flare-associated kink oscillations and extreme-ultraviolet waves

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science China(Technological sciences) 2024年第5期67卷 1592-1601页

作者： LI Dong HOU ZhenYong BAI XianYong LI Chuan FANG Matthew ZHAO HaiSheng WANG JinCheng NING ZongJun key laboratory of Dark Matter and space astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing210023China Yunnan key laboratory of the Solar Physics and space science Kunming650216China school of Earth and space sciences Peking UniversityBeijing100871China National Astronomical Observatories Chinese Academy of SciencesBeijing100101China school of astronomy and space science University of Chinese Academy of SciencesBeijing100049China school of astronomy and space science Nanjing UniversityNanjing210023China key laboratory of Modern astronomy and Astrophysics Ministry of EducationNanjing UniversityNanjing210023China Columbus Academy GahannaOhio43230USA key laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing100049China Yunnan Observatories Chinese Academy of SciencesKunming650216China

Kink oscillations,which are frequently observed in coronal loops and prominences,are often accompanied by extreme-ultraviolet(EUV)***,much more needs to be explored regarding the causal relationships between kink oscillations and EUV *** this article,we report the simultaneous detection of kink oscillations and EUV waves that are both associated with an X2.1 flare on 2023 March 03(SOL2023-03-03T17:39).The kink oscillations,which are almost perpendicular to the axes of loop-like structures,are observed in three coronal loops and one *** short loop shows in-phase oscillation within the same period of 5.2 min at three *** oscillation could be triggered by the pushing of an expanding loop and interpreted as the standing kink *** lags are found between the kink oscillations of the short loop and two long loops,suggesting that the kink wave travels in different *** kink oscillations of one long loop and the prominence are possibly driven by the disturbance of the coronal mass ejection(CME),and that of another long loop might be attributed to the interaction of the EUV *** onset time of the kink oscillation of the short loop is nearly same as the beginning of an EUV *** fact demonstrates that they are almost *** EUV wave is most likely excited by the expanding loop structure and shows two *** leading component is a fast coronal wave,and the trailing one could be due to the stretching magnetic field lines.

关键词： coronal loops solar flares solar prominence solar oscillations extreme-ultraviolet wave magnetohydrodynamic

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Black holes as the source of dark energy:A stringent test with high-redshift JWST AGNs

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science China(Physics,Mechanics & astronomy) 2024年第2期67卷 181-188页

作者： Lei Lei Lei Zu Guan-Wen Yuan Zhao-Qiang Shen Yi-Ying Wang Yuan-Zhu Wang Zhen-Bo Su Wen-Ke Ren Shao-Peng Tang Hao Zhou Chi Zhang Zhi-Ping Jin Lei Feng Yi-Zhong Fan Da-Ming Wei key laboratory of Dark Matter and space astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China school of astronomy and space science University of Science and Technology of ChinaHefei 230026China CAS key laboratory for Research in Galaxies and Cosmology Department of AstronomyUniversity of Science and Technology of ChinaHefei 230026China

Studies have proposed that there is evidence for cosmological coupling of black holes(BHs)with an index of k≈3;hence,BHs serve as the astrophysical source of dark ***,the data sample is limited for the redshifts of≤*** recent years,the James Webb space Telescope(JWST)has detected many high-redshift active galactic nuclei(AGNs)and *** the JWST NIRSpec-/NIRCam-resolved AGNs,three are determined to be in early-type host galaxies with a redshift of z~***,their M_(*)and MBH are in tension with the predicted cosmological coupling of black holes with k=3 at a confidence level of~2σ,which challenges the hypothesis that BHs serve as the origin of dark *** work on high-redshift AGNs using the JWST will further assess such a hypothesis by identifying more early-type host galaxies in the higher mass range.

关键词： dark energy supermassive black hole active galactic nuclei James Webb space Telescope

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Evolution of High-energy Electron Distribution in Pulsar Wind Nebulae

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Research in astronomy and Astrophysics 2024年第7期24卷 201-217页

作者： Yi-Ming Liu Hou-Dun Zeng Yu-Liang Xin Si-Ming Liu Yi Zhang key laboratory of Dark Matter and space astronomy Purple Mountain ObservatoryChinese Academy of Sciences school of astronomy and space science University of Science and Technology of China school of Physical science and Technology Southwest Jiaotong University

In this paper,we analyze the spectral energy distributions of 17 powerful (with a spin-down luminosity greater than1035erg s-1) young （with an age less than 15,000 yr） pulsar wind nebulae （PWNe） using a simple timein-dependent one-zone emission *** aim is to investigate correlations between model parameters and the ages of the corresponding PWNe,thereby revealing the evolution of high-energy electron distributions within *** findings are as follows:（1） The electron distributions in PWNe can be characterized by a double power-law with a super-exponential cutoff.（2） As PWNe evolve,the high-energy end of the electron distribution spectrum becomes harder with the index decreasing from approximately 3.5 to 2.5,while the low-energy end spectrum index remains constant near 1.5.（3） There is no apparent correlation between the break energy or cutoff energy and the age of PWNe.（4） The average magnetic field within PWNe decreases with age,leading to a positive correlation between the energy loss timescale of electrons at the break energy or the high-energy cutoff and the age of the PWN.（5） The total electron energy within PWNe remains constant near 2×1048erg,while the total magnetic energy decreases with age.

关键词： gamma-rays: general ISM: general ISM: supernova remnants radiation mechanisms: non-thermal

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Forecast of cosmological constraints with superluminous supernovae from the Chinese space Station Telescope

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science China(Physics,Mechanics & astronomy) 2024年

作者： Xuan-Dong Jia Jian-Ping Hu Fa-Yin Wang Zi-Gao Dai school of astronomy and space science Nanjing University key laboratory of Modern astronomy and Astrophysics (Nanjing University) Ministry of Education Department of astronomy University of Science and Technology of China

Superluminous supernovae（SLSNe） are a class of intense celestial events that can be standardized for measuring cosmological parameters, bridging the gap between type Ia supernovae and the cosmic microwave background. In this work, we discuss the cosmological applications of SLSNe from the Chinese space Station Telescope（CSST）. Our estimation suggests that SLSNe rate is biased tracing the cosmic star formation rate, exhibiting a factor of（1 + z）1.2. We futher predict that CSST is poised to observe ～ 360 SLSNe in the 10 square degrees ultra-deep field survey within a span of 2.5 years. A stringent constraint on cosmological parameters can be derived from their peak-color relationship. CSST is anticipated to uncover a substantial number of SLSNe, contributing to a deeper understanding of their central engines and shedding light on the nature of dark energy at high redshifts.

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Spontaneous anchoring Cl intoα-Co(OH)_(2) as efficient and stable oxygen reduction electrocatalysts for seawater battery

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Rare Metals 2024年第7期43卷 3074-3083页

作者： Wang Zheng Xue-Rong Zheng Qi Lu Yan-Hui Cao Yang Wang Hai-Peng Fu Jin-Feng Zhang Yi-Da Deng Wen-Bin Hu school of Materials science and Engineering Key Laboratory of Advanced Ceramics and Machining Technology of Ministry of EducationTianjin UniversityTianjin 300072China State key laboratory of Marine Resource Utilization in South China Sea School of Materials Science and EngineeringHainan UniversityHaikou 570228China key laboratory of Electromagnetic Processing of Materials Ministry of EducationNortheastern UniversityShenyang 110819China

Seawater battery is an advanced energy storage system that enables conversion of chemical energy to electricity by consuming metals,dissolved oxygen and seawater in anode,cathode and electrolyte,***,the oxygen reduction reaction(ORR)activity and stability of electrocatalysts can be easily deactivated due to the severe Cl~-permeation and corrosion in seawater ***,we developed a structural buffer engineering strategy by spontaneously anchoring Cl~-intoα-Co(OH)_(2) as efficient and stable ORR electrocatalysts,in which the ultrathinα-Co(OH)_(2) nanosheets were synthesized using an ultrafast solution high-temperature shock(SHTS)*** large lattice space(~0.8 nm)of layeredα-Co(OH)_(2) ensured the spontaneously penetration of Cl~-into the lattice structure and replaced part of OH~-to formα-Co(OH)_(2-x)Cl_*** continuous leaching and compensating of saturated Cl inα-Co(OH)_(2-x)Cl_x could enhance the Cl~-corrosion resistance and modulate electronic structure of Co metallic sites,thus improving the ORR electrocatalytic activity and stability in seawater ***α-Co(OH)_(2-x)Cl_x seawater batteries display superior onset and half-wave potentials of 0.71 and 0.66 V,respectively,which are much better than the counterparts ofα-Co(OH)_(2) and ofβ-Co(OH)_(2) with no Cl~-penetrating and no buffer ***α-Co(OH)_(2-x)Cl_x-based seawater batteries display stable open-circuit potential of 1.69 V and outstanding specific capacity of 1345 mAh·g^(-1).

关键词： Seawater battery Oxygen reduction electrocatalyst Solution high-temperature shock Structural buffer engineering

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Are Solar Active Regions Born with Neutralized Currents?

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Research in astronomy and Astrophysics 2024年第7期24卷 82-91页

作者： Aiying Duan Yaoyu Xing Chaowei Jiang Planetary Environmental and Astrobiological Research laboratory (PEARL) School of Atmospheric SciencesSun Yat-sen University Yunnan key laboratory of the Solar Physics and space science key laboratory of Tropical Atmosphere-Ocean System Sun Yat-sen UniversityMinistry of Education Institute of space science and Applied Technology Harbin Institute of Technology

Solar active regions(ARs) are formed by the emergence of current-carrying magnetic flux tubes from below the photosphere. Although for an isolated flux tube the direct and return currents flowing along the tube should balance with each other, it remains controversial whether such a neutralization of currents is also maintained during the emergence process. Here we present a systematic survey of the degrees of the current neutralization in a large sample of flux-emerging ARs which appeared on the solar disk around the central meridian from 2010 to *** vector magnetograms taken by Helioseismic and Magnetic Imager onboard Solar Dynamic Observatory are employed to calculate the distributions of the vertical current density at the photosphere. Focusing on the main phase of flux emergence, i.e., the phase in which the total unsigned magnetic flux is continuously increased, we statistically examined the ratios of direct to return currents in all the ARs. Such a large-sample statistical study suggests that most of the ARs were born with currents close to neutralization. The degree of current neutralization seems to be not affected by the active-region size, the active-region growing rate, and the total unsigned *** only correlation of significance as found is that the stronger the magnetic field nonpotentiality is, the further the AR deviates from current neutrality, which supports previous event studies that eruption-productive ARs often have non-neutralized currents.

关键词： Sun: corona Sun: coronal mass ejections (CMEs) Sun: flares Sun: magnetic fields

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