Experimental Astronomy最新文献

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The ground calibration of the HERMES-Pathfinder payload flight models HERMES 探路者有效载荷飞行模型的地面校准
IF 2.7 3区 物理与天体物理
Experimental Astronomy Pub Date : 2024-10-26 DOI: 10.1007/s10686-024-09958-4
G. Dilillo, E. J. Marchesini, G. Baroni, G. Della Casa, R. Campana, Y. Evangelista, A. Guzmán, P. Hedderman, P. Bellutti, G. Bertuccio, F. Ceraudo, M. Citossi, D. Cirrincione, I. Dedolli, E. Demenev, M. Feroci, F. Ficorella, M. Fiorini, M. Gandola, M. Grassi, G. La Rosa, G. Lombardi, P. Malcovati, F. Mele, P. Nogara, A. Nuti, M. Perri, S. Pliego-Caballero, S. Pirrotta, S. Puccetti, I. Rashevskaya, F. Russo, G. Sottile, C. Tenzer, M. Trenti, S. Trevisan, A. Vacchi, G. Zampa, N. Zampa, F. Fiore
{"title":"The ground calibration of the HERMES-Pathfinder payload flight models","authors":"G. Dilillo,&nbsp;E. J. Marchesini,&nbsp;G. Baroni,&nbsp;G. Della Casa,&nbsp;R. Campana,&nbsp;Y. Evangelista,&nbsp;A. Guzmán,&nbsp;P. Hedderman,&nbsp;P. Bellutti,&nbsp;G. Bertuccio,&nbsp;F. Ceraudo,&nbsp;M. Citossi,&nbsp;D. Cirrincione,&nbsp;I. Dedolli,&nbsp;E. Demenev,&nbsp;M. Feroci,&nbsp;F. Ficorella,&nbsp;M. Fiorini,&nbsp;M. Gandola,&nbsp;M. Grassi,&nbsp;G. La Rosa,&nbsp;G. Lombardi,&nbsp;P. Malcovati,&nbsp;F. Mele,&nbsp;P. Nogara,&nbsp;A. Nuti,&nbsp;M. Perri,&nbsp;S. Pliego-Caballero,&nbsp;S. Pirrotta,&nbsp;S. Puccetti,&nbsp;I. Rashevskaya,&nbsp;F. Russo,&nbsp;G. Sottile,&nbsp;C. Tenzer,&nbsp;M. Trenti,&nbsp;S. Trevisan,&nbsp;A. Vacchi,&nbsp;G. Zampa,&nbsp;N. Zampa,&nbsp;F. Fiore","doi":"10.1007/s10686-024-09958-4","DOIUrl":"10.1007/s10686-024-09958-4","url":null,"abstract":"<div><p>HERMES-Pathfinder is a space-borne mission based on a constellation of six nano-satellites flying in a low-Earth orbit. The 3U CubeSats, to be launched in early 2025, host miniaturized instruments with a hybrid Silicon Drift Detector/scintillator photodetector system, sensitive to both X-rays and gamma-rays. A seventh payload unit is installed onboard SpIRIT, an Australian-Italian nano-satellite developed by a consortium led by the University of Melbourne and launched in December 2023. The project aims at demonstrating the feasibility of Gamma-Ray Burst detection and localization using miniaturized instruments onboard nano-satellites. The HERMES flight model payloads were exposed to multiple well-known radioactive sources for spectroscopic calibration under controlled laboratory conditions. The analysis of the calibration data allows both to determine the detector parameters, necessary to map instrumental units to accurate energy measurements, and to assess the performance of the instruments. We report on these efforts and quantify features such as spectroscopic resolution and energy thresholds, at different temperatures and for all payloads of the constellation. Finally we review the performance of the HERMES payload as a photon counter, and discuss the strengths and the limitations of the architecture.</p></div>","PeriodicalId":551,"journal":{"name":"Experimental Astronomy","volume":"58 3","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142518601","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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
Optical optimization of a multi-slit extreme ultraviolet spectrograph for global solar corona diagnostics 用于全球日冕诊断的多狭缝极紫外摄谱仪的光学优化
IF 2.7 3区 物理与天体物理
Experimental Astronomy Pub Date : 2024-10-21 DOI: 10.1007/s10686-024-09961-9
Yufei Feng, Xianyong Bai, Sifan Guo, Hui Tian, Lami Chan, Yuanyong Deng, Qi Yang, Wei Duan, Xiaoming Zhu, Xiao Yang, Zhiwei Feng, Zhiyong Zhang
{"title":"Optical optimization of a multi-slit extreme ultraviolet spectrograph for global solar corona diagnostics","authors":"Yufei Feng,&nbsp;Xianyong Bai,&nbsp;Sifan Guo,&nbsp;Hui Tian,&nbsp;Lami Chan,&nbsp;Yuanyong Deng,&nbsp;Qi Yang,&nbsp;Wei Duan,&nbsp;Xiaoming Zhu,&nbsp;Xiao Yang,&nbsp;Zhiwei Feng,&nbsp;Zhiyong Zhang","doi":"10.1007/s10686-024-09961-9","DOIUrl":"10.1007/s10686-024-09961-9","url":null,"abstract":"<div><p>The spatial-temporal evolution of coronal plasma parameters of the solar outer atmosphere at global scales, derived from solar full-disk imaging spectroscopic observation in the extreme-ultraviolet band, is critical for understanding and forecasting solar eruptions. We propose a multi-slits extreme ultraviolet imaging spectrograph for global coronal diagnostics with high cadence and present the preliminary instrument designs for the wavelength range from 18.3 to 19.8 nm. The instrument takes a comprehensive approach to obtain global coronal spatial and spectral information, improve the detected cadence and avoid overlapping. We first describe the relationship between optical properties and structural parameters, especially the relationship between the overlapping and the number of slits, and give a general multi-slits extreme-ultraviolet imaging spectrograph design process. The multilayer structure is optimized to enhance the effective areas in the observation band. Five distantly-separated slits are set to divide the entire solar field of view, which increase the cadence for raster scanning the solar disk by 5 times relative to a single slit. The spectral resolving power of the optical system with an aperture diameter of 150 mm are optimized to be greater than 1461. The spatial resolution along the slits direction and the scanning direction are about <span>(4.4^{prime prime })</span> and <span>(6.86^{prime prime })</span>, respectively. The Al/Mo/B<span>(_4)</span>C multilayer structure is optimized and the peak effective area is about 1.60 cm<span>(^2)</span> at 19.3 nm with a full width at half maximum of about 1.3 nm. The cadence to finish full-disk raster scan is about 5 minutes. Finally, the instrument performance is evaluated by an end-to-end calculation of the system photon budget and a simulation of the observational image and spectra. Our investigation shows that this approach is promising for global coronal plasma diagnostics.</p></div>","PeriodicalId":551,"journal":{"name":"Experimental Astronomy","volume":"58 3","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142452979","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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
Application of machine learning method for energy reconstruction on space based high granularity calorimeter 将机器学习方法应用于基于空间的高粒度热量计的能量重构
IF 2.7 3区 物理与天体物理
Experimental Astronomy Pub Date : 2024-10-19 DOI: 10.1007/s10686-024-09957-5
C. L. Liao, Z. Quan, Y. W. Dong, M. Xu., C. Zhang, J. J. Wang, X. G. Yang, Q. Wu, J. Y. Sun, X. Liu., Z. G. Wang., R. J. Wang.
{"title":"Application of machine learning method for energy reconstruction on space based high granularity calorimeter","authors":"C. L. Liao,&nbsp;Z. Quan,&nbsp;Y. W. Dong,&nbsp;M. Xu.,&nbsp;C. Zhang,&nbsp;J. J. Wang,&nbsp;X. G. Yang,&nbsp;Q. Wu,&nbsp;J. Y. Sun,&nbsp;X. Liu.,&nbsp;Z. G. Wang.,&nbsp;R. J. Wang.","doi":"10.1007/s10686-024-09957-5","DOIUrl":"10.1007/s10686-024-09957-5","url":null,"abstract":"<div><p>The High Energy Cosmic-Radiation Detection Facility (HERD) is dedicated to achieving several scientific objectives, including the search for dark matter, precise measurement of the cosmic ray spectrum, and gamma-ray sky survey observations. HERD’s innovative design incorporates a three-dimensional imaging calorimeter with five sensitive faces, significantly enhancing geometric acceptance. However, this design introduces a new challenge for reconstructing particles incident from all directions. This article aims to integrate rapidly advancing deep learning techniques into the reconstruction task. Utilizing simulation data, Deep Neural Networks (DNN), Convolutional Neural Networks (CNN), and other deep learning networks are employed to reconstruct the energy of isotropic electrons. Model performance sees a significant boost through the application of end-layer visible energy correction and a “multi-class multi-prediction” approach, involving different models trained for distinct energy ranges. Moreover, recognizing differences between simulation and physical samples, the model is validated using the beam test data. The model predicts an energy resolution of better than 1% for simulation isotropic electrons ranging from 10 to 1000 GeV. In the case of beam data, the model achieves an energy resolution of 1.3% at 200 GeV, comparable to traditional methods. The results demonstrate the significant potential of deep learning in the reconstruction of three-dimensional calorimeters.</p></div>","PeriodicalId":551,"journal":{"name":"Experimental Astronomy","volume":"58 3","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142451088","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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
Light-tracing based surface deformation measurement strategy for large radio telescopes 基于光跟踪的大型射电望远镜表面形变测量战略
IF 2.7 3区 物理与天体物理
Experimental Astronomy Pub Date : 2024-10-18 DOI: 10.1007/s10686-024-09960-w
Zihan Zhang, Dejin Yang, Qian Ye, Na Wang
{"title":"Light-tracing based surface deformation measurement strategy for large radio telescopes","authors":"Zihan Zhang,&nbsp;Dejin Yang,&nbsp;Qian Ye,&nbsp;Na Wang","doi":"10.1007/s10686-024-09960-w","DOIUrl":"10.1007/s10686-024-09960-w","url":null,"abstract":"<div><p>With the increasing aperture as well as the observation frequency of radio telescopes in the current period, the deformation caused by time-varying loads such as temperature and wind has been emphasized. Existing methods for measuring deformations often fall short in meeting the demands of full attitude coverage, quasi-real-time response, and high accuracy. This study introduces a novel geometric-optical measurement approach based on light-tracing. Diverging from traditional methods, this approach doesn’t directly measure the surface deformation of the main reflector. Instead, it creates a more easily measurable variable and establishes a mapping relationship between this variable and the main reflector deformation. In this innovative scheme, multiple laser modules are strategically positioned on the main reflector, treating the sub reflector as a spot projection surface. When the panel is displaced, the spot on the projection surface will follow and be displaced. In practice, the main reflector deformation can be solved by recording the position change of the light spots on the projection surface and utilizing the inverse reconstruction model. Besides, effective strategies are proposed to improve the robustness of the scheme. Next, the accuracy and real-time performance of the proposed method are verified through simulations and experiments. Results indicate that the proposed approach presents a fresh perspective to enhance the efficiency and precision of deformation measurements for large-aperture antennas.</p></div>","PeriodicalId":551,"journal":{"name":"Experimental Astronomy","volume":"58 3","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142447314","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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 thermo-optical test device utilizing the 100-m x-ray test facility 利用 100 米 X 射线测试设备的热光学测试装置
IF 2.7 3区 物理与天体物理
Experimental Astronomy Pub Date : 2024-10-13 DOI: 10.1007/s10686-024-09959-3
Jia Ma, Yusa Wang, Zijian Zhao, Dongjie Hou, Juan Wang, Xiongtao Yang, Yuxuan Zhu, Jianchao Feng, Xiaofan Zhao, Weiwei Cui, Yanji Yang, Yong Chen, Xiaofeng Zhang
{"title":"A thermo-optical test device utilizing the 100-m x-ray test facility","authors":"Jia Ma,&nbsp;Yusa Wang,&nbsp;Zijian Zhao,&nbsp;Dongjie Hou,&nbsp;Juan Wang,&nbsp;Xiongtao Yang,&nbsp;Yuxuan Zhu,&nbsp;Jianchao Feng,&nbsp;Xiaofan Zhao,&nbsp;Weiwei Cui,&nbsp;Yanji Yang,&nbsp;Yong Chen,&nbsp;Xiaofeng Zhang","doi":"10.1007/s10686-024-09959-3","DOIUrl":"10.1007/s10686-024-09959-3","url":null,"abstract":"<div><p>X-ray mirror modules are the core components of X-ray astronomy research, which can focus X-rays from space and significantly improve detection sensitivity. This X-ray optical device are typically composed of nested multiple mirror shells and require maintaining a constant working temperature. Due to the thin-walled structure of the mirror shells and the fact that the inner surface reflects X-rays, direct contact temperature control is not feasible, making temperature control challenging. To evaluate the thermo-optical performance of the mirrors, based on the 100-m X-ray Test Facility (100XF) of the Institute of High Energy Physics (IHEP), a thermo-optical test device with high cleanliness was developed in this study. This system enables precise control of the mirror temperature and synchronous testing of X-ray performance, establishing the unique X-ray thermo-optical testing capability in China. The system consists of a high cleanliness level thermal sink, a liquid nitrogen circuit, multi-layer insulation, a temperature controller, and low-temperature probes. This system has demonstrated the capability to test the thermo-optical performance of X-ray mirror modules and has successfully conducted thermo-optical tests on the mirror module of the follow-up X-ray telescope (FXT) payload onboard the Einstein Probe (EP), achieving precise temperature control of the X-ray mirrors and testing its X-ray optical performance at different operating temperatures. The thermo-optical performance of the mirror module obtained from the thermal tests has been verified in-orbit. This paper provides a detailed description of the design, development, and validation of this system, as well as an overview of the results of the thermo-optical tests conducted on the FXT.</p></div>","PeriodicalId":551,"journal":{"name":"Experimental Astronomy","volume":"58 2","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142431050","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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
Using SRG/eROSITA to predict soft proton induced ATHENA backgrounds 利用 SRG/eROSITA 预测软质子诱导的 ATHENA 背景
IF 2.7 3区 物理与天体物理
Experimental Astronomy Pub Date : 2024-10-12 DOI: 10.1007/s10686-024-09956-6
Emanuele Perinati, Michael J. Freyberg, Michael C. H. Yeung, Konrad Dennerl, Christian Pommranz, Bastian Heß, Sebastian Diebold, Chris Tenzer, Andrea Santangelo
{"title":"Using SRG/eROSITA to predict soft proton induced ATHENA backgrounds","authors":"Emanuele Perinati,&nbsp;Michael J. Freyberg,&nbsp;Michael C. H. Yeung,&nbsp;Konrad Dennerl,&nbsp;Christian Pommranz,&nbsp;Bastian Heß,&nbsp;Sebastian Diebold,&nbsp;Chris Tenzer,&nbsp;Andrea Santangelo","doi":"10.1007/s10686-024-09956-6","DOIUrl":"10.1007/s10686-024-09956-6","url":null,"abstract":"<div><p>Soft protons populating the space environment have affected the performance of the X-ray detectors on board Chandra and XMM-Newton, and they pose a threat for future high energy astrophysics missions with larger aperture, such as ATHENA. In this paper, we aim to predict the soft proton induced ATHENA backgrounds from the modelling of the orbital flux obtained using eROSITA on board SRG. To this end, we analysed the background measured by eROSITA and with the help of simulations we defined a range of values for the potential count-rate of quiet-time soft protons focused through the mirror shells. We used it to derive an estimate of the orbital soft proton flux, from which the induced background for the WFI and X-IFU detectors can be predicted, assuming ATHENA in the same L2-orbit as SRG. The scaling, based on the computed proton transmission yields of the optics and optical/thermal filters, indicates that the soft proton induced WFI and X-IFU backgrounds could be expected within the requirement. Regardless of where ATHENA will be placed (L1 or L2), our analysis also suggests that increasing somewhat the thickness of the WFI optical blocking filter, e.g. by <span>(sim )</span>30%, would help to further reduce the soft proton flux onto the detector, which might be worth in case the planned magnetic diverters perform worse than expected due to soft proton neutralisation at the mirror level.</p></div>","PeriodicalId":551,"journal":{"name":"Experimental Astronomy","volume":"58 2","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10686-024-09956-6.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142411487","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Analysis of long term atmospheric properties for Eastern Anatolia observatory (DAG) site 东安纳托利亚观测站(DAG)站点的长期大气特性分析
IF 2.7 3区 物理与天体物理
Experimental Astronomy Pub Date : 2024-10-08 DOI: 10.1007/s10686-024-09952-w
Funda Yuzlukoglu, Cahit Yesilyaprak, Kazım Kaba, Tuba Ikiz, Mohammad Shameoni Niaei
{"title":"Analysis of long term atmospheric properties for Eastern Anatolia observatory (DAG) site","authors":"Funda Yuzlukoglu,&nbsp;Cahit Yesilyaprak,&nbsp;Kazım Kaba,&nbsp;Tuba Ikiz,&nbsp;Mohammad Shameoni Niaei","doi":"10.1007/s10686-024-09952-w","DOIUrl":"10.1007/s10686-024-09952-w","url":null,"abstract":"<div><p>Eastern Anatolia Observatory (DAG), located at 39.78 degrees North latitude (N) and 41.23 degrees East longitude (E) with 3170 m altitude above the sea level in the east part of Türkiye, having the first 4m class infrared (IR) telescope. DAG telescope is not only the largest telescope in Türkiye but also the most important telescope in the northern hemisphere because it also covers a large observational gap thanks to its location over the World. The atmospheric conditions of the DAG site have a major impact on the quality of observations in ground-based astronomy. The atmospheric conditions of an observatory site being effective and important for both optical and infrared observations is a key parameter in assessing the performance of astronomic observations and observatory sites. In this study, as an observatory site, a detailed long-term atmospheric and astronomical analysis of DAG site were presented for near-infrared observations, especially. Within the scope of basic atmospheric and astronomical parameters, it has been revealed that the DAG site is an observatory site with a great astronomical observation potential, due to its location, robust infrastructure, astronomical and atmospheric properties originating from geography.</p></div>","PeriodicalId":551,"journal":{"name":"Experimental Astronomy","volume":"58 2","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142410732","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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
Study of the relationship between metrological characterization and angular resolution in grazing-incidence X-ray optics 掠入射 X 射线光学中计量特征与角度分辨率之间关系的研究
IF 2.7 3区 物理与天体物理
Experimental Astronomy Pub Date : 2024-09-24 DOI: 10.1007/s10686-024-09955-7
L. Q. Qi, Y. X. Zhu, X. Z. Ding, Y. P. Xu, D. F. Wang, T. X. Chen, D. Z. Diao, F. G. Yang, G. Li, D. Xie, Y. S. Wang, S. Yang, T. Luo, M. Y. Ge, Z. W. Li
{"title":"Study of the relationship between metrological characterization and angular resolution in grazing-incidence X-ray optics","authors":"L. Q. Qi,&nbsp;Y. X. Zhu,&nbsp;X. Z. Ding,&nbsp;Y. P. Xu,&nbsp;D. F. Wang,&nbsp;T. X. Chen,&nbsp;D. Z. Diao,&nbsp;F. G. Yang,&nbsp;G. Li,&nbsp;D. Xie,&nbsp;Y. S. Wang,&nbsp;S. Yang,&nbsp;T. Luo,&nbsp;M. Y. Ge,&nbsp;Z. W. Li","doi":"10.1007/s10686-024-09955-7","DOIUrl":"10.1007/s10686-024-09955-7","url":null,"abstract":"<div><p>The grazing-incidence optics with Wolter-I type geometry is commonly used in X-ray astronomy. The manufacturing technologies are still under development for future space missions to fulfill the stringent performance requirements with reduced weight and cost, e.g. the planned enhanced X-ray Timing and Polarimetry Mission. To improve the manufacturing process, it is necessary to study the relationship between metrological characterization and angular resolution via ray-optics or wave-optics models. The model calculations produce inconsistent results depending on the characteristics of wide-band surface errors, which require validation before their application in the Wolter-I type optics. In this work, two samples of the single-reflection mirrors with an elliptical shape are produced to validate the models. The first sample uses the Aluminum alloy substrate and the second sample uses the Aluminum alloy coated with Nickel-Phosphorous as the substrate. Tungsten is coated on both substrates to increase the X-ray reflectivity. The metrological characterization is inspected using the Fizeau interferometer and 3D optical profiler. The X-ray calibration of the mirror is performed in the 100-m X-ray Test Facility of Institute of High Energy Physics using the Color X-ray Camera. Both ray-optics and wave-optics models are validated in a wide scope of applications from smooth to relatively rough surfaces. The proper treatments of the metrological data are required as input to the model calculations: the post-fit distribution of figure errors, the micro-roughness defined in a specific frequency band, and the smoothed power spectral density of the surface errors. The validated models can be further applied in Wolter-I optics to predict mirror performances or to provide precision processing requirements.</p></div>","PeriodicalId":551,"journal":{"name":"Experimental Astronomy","volume":"58 2","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142413532","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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
Calibration of spectropolarimetry channel of visible emission line coronagraph onboard Aditya-L1 校准 Aditya-L1 上可见发射线日冕仪的摄谱仪通道
IF 2.7 3区 物理与天体物理
Experimental Astronomy Pub Date : 2024-09-13 DOI: 10.1007/s10686-024-09954-8
Venkata Suresh Narra, K. Sasikumar Raja, Raghavendra Prasad B, Jagdev Singh, Shalabh Mishra, Sanal Krishnan V U, Bhavana Hegde S, Utkarsha D., Natarajan V, Pawan Kumar S, Muthu Priyal V, Savarimuthu P, Priya Gavshinde, Umesh Kamath P
{"title":"Calibration of spectropolarimetry channel of visible emission line coronagraph onboard Aditya-L1","authors":"Venkata Suresh Narra,&nbsp;K. Sasikumar Raja,&nbsp;Raghavendra Prasad B,&nbsp;Jagdev Singh,&nbsp;Shalabh Mishra,&nbsp;Sanal Krishnan V U,&nbsp;Bhavana Hegde S,&nbsp;Utkarsha D.,&nbsp;Natarajan V,&nbsp;Pawan Kumar S,&nbsp;Muthu Priyal V,&nbsp;Savarimuthu P,&nbsp;Priya Gavshinde,&nbsp;Umesh Kamath P","doi":"10.1007/s10686-024-09954-8","DOIUrl":"10.1007/s10686-024-09954-8","url":null,"abstract":"<div><p>The magnetic field strength and its topology play an important role in understanding the formation, evolution, and dynamics of the solar corona. Also, it plays a significant role in addressing long-standing mysteries such as coronal heating problem, origin and propagation of coronal mass ejections, drivers of space weather, origin and acceleration of solar wind, and so on. Despite having photospheric magnetograms for decades, we do not have reliable observations of coronal magnetic field strengths today. To measure the coronal magnetic field precisely, the spectropolarimetry channel of the Visible Emission Line Coronagraph (VELC) on board the Aditya-L1 mission is designed. Using the observations of coronal emission line Fe XIII [10747Å ], it is possible to generate full Stokes maps (I, Q, U, and V) that help in estimating the Line-of-Sight (LOS) magnetic field strength and to derive the magnetic field topology maps of solar corona in the Field of View (FOV) (1.05 – 1.5 R<span>(_{odot })</span>). In this article, we summarize the instrumental details of the spectropolarimetry channel and detailed calibration procedures adopted to derive the modulation and demodulation matrices. Furthermore, we have applied the derived demodulation matrices to the observed data in the laboratory and studied their performance.</p></div>","PeriodicalId":551,"journal":{"name":"Experimental Astronomy","volume":"58 2","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142215894","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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
Bayesian and convolutional networks for hierarchical morphological classification of galaxies 用于星系分层形态分类的贝叶斯和卷积网络
IF 2.7 3区 物理与天体物理
Experimental Astronomy Pub Date : 2024-08-31 DOI: 10.1007/s10686-024-09950-y
Jonathan Serrano-Pérez, Raquel Díaz Hernández, L. Enrique Sucar
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