Research in Astronomy and Astrophysics最新文献_第8页

Simulation of RFI cancellation using Subspace Projection Algorithm for PAF receiver 基于子空间投影算法的PAF接收机射频对消仿真

4区物理与天体物理

Research in Astronomy and Astrophysics Pub Date : 2023-11-10 DOI: 10.1088/1674-4527/ad0b84

wu peng, li jian, Maozheng Chen

引用次数: 0

Study on the Performance of the GRANDProto300 Particle Detector Array by Simulation GRANDProto300粒子探测器阵列性能的仿真研究

4区物理与天体物理

Research in Astronomy and Astrophysics Pub Date : 2023-11-06 DOI: 10.1088/1674-4527/ad0a31

Fu-Lin Dai, Quan-Bu Gou, Xiaoyuan Huang, Yi-Qing Guo

{"title":"Study on the Performance of the GRANDProto300 Particle Detector Array by Simulation","authors":"Fu-Lin Dai, Quan-Bu Gou, Xiaoyuan Huang, Yi-Qing Guo","doi":"10.1088/1674-4527/ad0a31","DOIUrl":"https://doi.org/10.1088/1674-4527/ad0a31","url":null,"abstract":"Abstract The Giant Radio Array for Neutrino Detection (GRAND) is a proposed large-scale observatory designed to detect cosmic rays, gamma rays, and neutrinos with energies exceeding 100 PeV. The GRANDProto300 experiment is proposed as the early stage of the GRAND project, consisting of a hybrid array of radio antennas and scintillator detectors. The latter, as a mature and traditional detector, is used to cross-check the nature of the candidate events selected from radio observations. In this study, we developed a simulation software called G4GRANDProto300, based on the Geant4 software package, to optimize the spacing of the scintillator detector array and to investigate its effective area. The analysis was conducted at various zenith angles under different detector spacings, including 300 m, 500 m, 600 m, 700 m, and 900 m. Our results indicate that, for large zenith angles used to search for cosmic-ray in the GRAND project, the optimized effective area is with a detector spacing of 500 m. And the G4GRANDProto300 software that we developed could be used to further optimize the layout of the particle detector array in future work.","PeriodicalId":54494,"journal":{"name":"Research in Astronomy and Astrophysics","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135589256","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

An analysis of the fragmentation of observing time at the Muztagh-ata site Muztagh-ata站点观测时间碎片化分析

4区物理与天体物理

Research in Astronomy and Astrophysics Pub Date : 2023-11-06 DOI: 10.1088/1674-4527/ad0a32

Wenbo Gu, Jing Xu, Guojie Feng, Xuan Zhang, Letian Wang, Xinliang Wang, Ali Esamdin, Lixian Shen

引用次数: 0

A Cross-matching Service for Data Center of Xinjiang Astronomical Observatory 新疆天文台数据中心交叉匹配服务

4区物理与天体物理

Research in Astronomy and Astrophysics Pub Date : 2023-11-02 DOI: 10.1088/1674-4527/ad08e8

hailong zhang, Jie WANG, Xinchen YE, Wanqiong WANG, Jia LI, Zhang Yazhou, Xu Du, Han Wu, Ting ZHANG

{"title":"A Cross-matching Service for Data Center of Xinjiang Astronomical Observatory","authors":"hailong zhang, Jie WANG, Xinchen YE, Wanqiong WANG, Jia LI, Zhang Yazhou, Xu Du, Han Wu, Ting ZHANG","doi":"10.1088/1674-4527/ad08e8","DOIUrl":"https://doi.org/10.1088/1674-4527/ad08e8","url":null,"abstract":"Abstract Cross-matching is a key technique to achieve fusion of multi-band astronomical catalogs. Due to different equipment such as various astronomical telescopes, the existence of measurement errors and proper motions of the celestial bodies, the same celestial object will have different positions in different catalogs, making it difficult to integrate multi-band or full-band astronomical data. In this study, We propose an online cross-matching method based on pseudo-spherical indexing techniques and develop a service combining with high performance computing system (Taurus) to improve cross-matching efficiency, which is designed for the Data Center of Xinjiang Astronomical Observatory (XAO-DC). Specifically, we use Q3C (Quad Tree Cube) to divide the spherical blocks of celestial object and map the 2-D space composed of Right Ascension (RA) and Declination (Dec) to 1-D space and achieve correspondence between real celestial objects and spherical patches. Finally, we verify the performance of the service using GAIA 3 and PPMXL catalogs. Meanwhile, we send the matching results to VO tools-Topcat and Aladin respectively to get visual results. The experimental results show that the service effectively solves the speed bottleneck problem of cross-matching caused by frequent I/O, and significantly improves the retrieval and matching speed of massive astronomical data.","PeriodicalId":54494,"journal":{"name":"Research in Astronomy and Astrophysics","volume":"18 S6","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135875985","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Formation of a rapidly rotating classical Be-star in a massive close binary system 在大质量紧密双星系统中快速旋转的经典be星的形成

4区物理与天体物理

Research in Astronomy and Astrophysics Pub Date : 2023-11-01 DOI: 10.1088/1674-4527/ad089e

Evgeny Staritsin

引用次数: 0

Design and cryogenic performance of a hexapod platform for large ground-based wide field survey telescope 大型陆基广域观测望远镜六足平台设计及低温性能研究

4区物理与天体物理

Research in Astronomy and Astrophysics Pub Date : 2023-10-31 DOI: 10.1088/1674-4527/ad0865

Yang Yu, Xuewen Wang, Yu Zhang, Jialin Sun, zhenbang xu, Jianli Wang

{"title":"Design and cryogenic performance of a hexapod platform for large ground-based wide field survey telescope","authors":"Yang Yu, Xuewen Wang, Yu Zhang, Jialin Sun, zhenbang xu, Jianli Wang","doi":"10.1088/1674-4527/ad0865","DOIUrl":"https://doi.org/10.1088/1674-4527/ad0865","url":null,"abstract":"Abstract Thermal gradient is an important factor causing degradation in the image quality of telescopes. In order to ensure the accurate alignment of the primary focus unit and the primary mirror, the hexapod platform (as a corrector) is investigated in this paper. First, a ground-based telescope with 2.5 m aperture and 3.5 deg field of view is described. The telescope is under construction, and it is expected to be finished in 2023. Secondly, the hexapod platform with flexure hinges utilized to adjust the primary focus unit is proposed, which is applied as a corrector. Then, the inverse kinematics of the platform is established and an open-loop control system is built based on it. Finally, the cryogenic performance test for the hexapod platform is performed. The experimental results show that the resolution and repeatability of the translation for the hexapod platform can be achieved at the micro-meter level. The resolution and repeatability of the rotation can be achieved at the arc-second level. Therefore, the cryogenic performance of the hexapod platform can meet the optical imaging requirements of the wide-field ground-based telescope. The kinematic analysis and cryogenic performance tests in the paper provide a technical reference for the precise alignment of the primary focus unit and the primary mirror, which can improve the imaging quality of the telescope.","PeriodicalId":54494,"journal":{"name":"Research in Astronomy and Astrophysics","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135808529","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A comparison of co-temporal vector magnetograms obtained with HMI/SDO and SP/Hinode HMI/SDO和SP/Hinode共时矢量磁图的比较

4区物理与天体物理

Research in Astronomy and Astrophysics Pub Date : 2023-10-31 DOI: 10.1088/1674-4527/ad013f

Mei Zhang, Haocheng Zhang, Chengqing Jiang

{"title":"A comparison of co-temporal vector magnetograms obtained with HMI/SDO and SP/Hinode","authors":"Mei Zhang, Haocheng Zhang, Chengqing Jiang","doi":"10.1088/1674-4527/ad013f","DOIUrl":"https://doi.org/10.1088/1674-4527/ad013f","url":null,"abstract":"Abstract Accurate measurement of magnetic fields is very important for understanding the formation and evolution of solar magnetic fields. Currently, there are two types of solar magnetic field measurement instruments: filter-based magnetographs and Stokes polarimeters. The former gives high temporal resolution magnetograms and the latter provides more accurate measurements of magnetic fields. Calibrating the magnetograms obtained by filter-based magnetographs with those obtained by Stokes polarimeters is a good way to combine the advantages of the two types. Our previous studies have shown that, compared to the magnetograms obtained by the Spectro-Polarimeter (SP) on board Hinode, those magnetograms obtained by both the filter-based Solar Magnetic Field Telescope (SMFT) of the Huairou Solar Observing Station and by the filter-based Michelson Doppler Imager (MDI) aboard SOHO have underestimated the flux densities in their magnetograms and systematic center-to-limb variations present in the magnetograms of both instruments. Here, using a sample of 75 vector magnetograms of stable alpha sunspots, we compare the vector magnetograms obtained by the Helioseismic and Magnetic Imager (HMI) aboard Solar Dynamics Observatory (SDO) with co-temporal vector magnetograms acquired by SP/Hinode. Our analysis shows that both the longitudinal and transverse flux densities in the HMI/SDO magnetograms are very close to those in the SP/Hinode magnetograms and the systematic center-to-limb variations in the HMI/SDO magnetograms are very minor. Our study suggests that using a filter-based magnetograph to construct a low spectral resolution Stokes profile, as done by HMI/SDO, can largely remove the disadvantages of the filter-type measurements and yet still possess the advantage of high temporal resolution.","PeriodicalId":54494,"journal":{"name":"Research in Astronomy and Astrophysics","volume":"198 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135765709","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Implications of the Stellar Mass Density of High-$z$ Massive Galaxies from JWST on Warm Dark Matter 来自JWST的高z大质量星系的恒星质量密度对热暗物质的影响

4区物理与天体物理

Research in Astronomy and Astrophysics Pub Date : 2023-10-31 DOI: 10.1088/1674-4527/ad0864

Hengjie Lin, Yan Gong, Bin Yue, Xuelei Chen

{"title":"Implications of the Stellar Mass Density of High-$z$ Massive Galaxies from JWST on Warm Dark Matter","authors":"Hengjie Lin, Yan Gong, Bin Yue, Xuelei Chen","doi":"10.1088/1674-4527/ad0864","DOIUrl":"https://doi.org/10.1088/1674-4527/ad0864","url":null,"abstract":"Abstract A significant excess of the stellar mass density at high redshift has been discovered from the early data release of James Webb Space Telescope ($it{JWST}$), and it may require a high star formation efficiency. However, this will lead to large number density of ionizing photons in the epoch of reionization (EoR), so that the reionization history will be changed, which can arise tension with the current EoR observations. Warm dark matter (WDM), via the free streaming effect, can suppress the formation of small-scale structure as well as low-mass galaxies. This provides an effective way to decrease the ionizing photons when considering a large star formation efficiency in high-$z$ massive galaxies without altering the cosmic reionization history. On the other hand, the constraints on the properties of warm dark matter can be derived from the $it JWST$ observations. In this work, we study WDM as a possible solution to reconcile the $it JWST$ stellar mass density of high-$z$ massive galaxies and reionization history. {color{red}We find that, the $it JWST$ high-$z$ comoving cumulative stellar mass density alone has no significant preference for either CDM or WDM model. But using the observational data of other stellar mass density measurements and reionization history, we obtain that the WDM particle mass with $m_{text{W}} = 0.51^{+0.22}_{-0.12}$ eV and star formation efficiency parameter $f_{*}^0>0.39$ in 2$sigma$ confidence level can match both the $it JWST$ high-$z$ comoving cumulative stellar mass density and the reionization history.","PeriodicalId":54494,"journal":{"name":"Research in Astronomy and Astrophysics","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135808240","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Two-dimensional Parameter Relationships for W UMa-type Systems Revisited wuma型系统的二维参数关系

4区物理与天体物理

Research in Astronomy and Astrophysics Pub Date : 2023-10-31 DOI: 10.1088/1674-4527/ad0866

Atila Poro, Ehsan Paki, Ailar Alizadehsabegh, Mehdi Khodadadilori, Selda Ranjbar Salehian, Mahya Hedayatjoo, Fatemeh Hashemi, Yasaman Dashti, Fatemeh Mohammadizadeh

引用次数: 0

Disturbance Observer-based Pointing Control of Leighton Chajnantor Telescope 基于扰动观测器的Leighton chajantor望远镜指向控制

4区物理与天体物理

Research in Astronomy and Astrophysics Pub Date : 2023-10-30 DOI: 10.1088/1674-4527/ad0826

Weirui Chen, Zheng Wang

{"title":"Disturbance Observer-based Pointing Control of Leighton Chajnantor Telescope","authors":"Weirui Chen, Zheng Wang","doi":"10.1088/1674-4527/ad0826","DOIUrl":"https://doi.org/10.1088/1674-4527/ad0826","url":null,"abstract":"Abstract Leighton Chajnantor Telescope (LCT), i.e., the former Caltech Submillimeter Observatory (CSO) telescope, will be refurbished at the new site in Chajnantor Plateau, Chile, in 2023. The environment of LCT will change significantly after its relocation, and the telescope will be exposed to large wind disturbance directly because its enclosure will be completely open during observation. The wind disturbance is expected to be a challenge for LCT’s pointing control since existing control method cannot reject this disturbance very well. Therefore, it is very necessary to develop a new pointing control method with good capability of disturbance rejection. In this research, a disturbance observer - based composite position controller (DOB-CPC) is designed, in which an H∞ feedback controller is employed to compress the disturbance, and a feedforward linear quadratic regulator is employed to compensate the disturbance precisely based on the estimated disturbance signal. Moreover, a controller switching policy (CSP) is adopted, which applies the proportional controller to the transient process to achieve a quick response and applies the DOB-CPC to the steady state to achieve a small position error. Numerical experiments are conducted to verify the good performance of the proposed pointing controller (i.e., DOB-CPC) for rejecting the disturbance acting on LCT.","PeriodicalId":54494,"journal":{"name":"Research in Astronomy and Astrophysics","volume":"281 ","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136102478","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0