Experimental Astronomy最新文献

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An investigation into the correlation between signal path variation and structural deformation in large radio telescopes 大型射电望远镜信号路径变化与结构变形的相关性研究
IF 2.9 3区 物理与天体物理
Experimental Astronomy Pub Date : 2026-07-08 DOI: 10.1007/s10686-026-10064-w
Lingling Wang, Jinqing Wang, Linfeng Yu, Yongchen Jiang, Qinghui Liu
{"title":"An investigation into the correlation between signal path variation and structural deformation in large radio telescopes","authors":"Lingling Wang,&nbsp;Jinqing Wang,&nbsp;Linfeng Yu,&nbsp;Yongchen Jiang,&nbsp;Qinghui Liu","doi":"10.1007/s10686-026-10064-w","DOIUrl":"10.1007/s10686-026-10064-w","url":null,"abstract":"<div><p>Signal path variation (SPV) in radio telescopes is a critical factor affecting observational accuracy, with structural deformation-induced path changes representing a primary error source. In Very Long Baseline Interferometry (VLBI) observations using large telescopes, such deformations introduce signal delays that compromise measurement precision, especially in high-accuracy applications like geodesy and spacecraft tracking. This study systematically investigates signal path variation patterns induced by structural deformations through theoretical analysis and experimental validation, focusing on four key mechanisms: gravitational deformation of main/sub-reflectors, thermal expansion/contraction of the main reflector, off-axis structural configurations, and antenna pointing errors. In the present paper, we analyse these mechanisms in the case of the Tianma 65-m radio telescope (TMRT) and of one prototype Square Kilometre Array (SKA) antenna. We determine that Z-direction displacement of the sub-reflector influences the SPV at a rate of 1.62 mm/mm, with an uncertainty of 0.012 mm. Elevation changes from 45° to 55° induce an SPV of 6.1 mm. A temperature variation of 20 °C leads to a 1.3 mm shift of the antenna reference point, with an associated uncertainty of 0.4 mm. For an off-axis structural antenna, an elevation deviation of 1 arcminute results in 0.4 mm of SPV, with uncertainty remaining below 8 μm. Additionally, a time delay of 1.1 ps occurs when the antenna pointing shifts away from the optimal position.</p></div>","PeriodicalId":551,"journal":{"name":"Experimental Astronomy","volume":"62 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2026-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148465368","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
Development of a cosmic ray detector using CMOS sensors embedded in smartphones and Raspberry Pi devices 利用嵌入智能手机和树莓派设备的CMOS传感器开发宇宙射线探测器
IF 2.9 3区 物理与天体物理
Experimental Astronomy Pub Date : 2026-07-01 DOI: 10.1007/s10686-026-10063-x
Wakiko Takano, Shigeharu Udo, Atsushi Shiomi, Kinya Hibino
{"title":"Development of a cosmic ray detector using CMOS sensors embedded in smartphones and Raspberry Pi devices","authors":"Wakiko Takano,&nbsp;Shigeharu Udo,&nbsp;Atsushi Shiomi,&nbsp;Kinya Hibino","doi":"10.1007/s10686-026-10063-x","DOIUrl":"10.1007/s10686-026-10063-x","url":null,"abstract":"<div><p>Cosmic rays are ubiquitous; however, their direct observation traditionally demands specialized, high-cost hardware and significant technical expertise, presenting a high barrier for non-specialist environments such as schools and community settings. We present <b>SORAMAME</b>, a smartphone and tablet application that lowers this barrier by repurposing built-in CMOS image sensors as particle detectors. The system enables real-time recording and visualization of particle-like events without additional hardware, integrating on-device extraction—calibration, noise filtering, and track-candidate detection—with cloud-based data management. By simplifying the detection process, SORAMAME facilitates widespread adoption across diverse user groups, fostering an environment where educational outreach can transition into large-scale data collection. This scalability is particularly significant given the unprecedented number of internet-connected consumer devices equipped with silicon CMOS image sensors. Despite the inherent constraints of consumer-grade sensors, our in-flight validation and Raspberry Pi-based measurements successfully captured altitude and latitude-dependent variations in particle flux consistent with geomagnetic shielding. These results suggest that lowering barriers to participation in observation not only serves educational purposes but also has the potential to contribute to future scientific breakthroughs through the development of global citizen science.</p></div>","PeriodicalId":551,"journal":{"name":"Experimental Astronomy","volume":"62 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148380524","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
Deposition and performance of depth-graded W/Si multilayers on silicon pore optics for the WXPT mission 用于WXPT任务的深度梯度W/Si多层硅孔光学器件的沉积和性能
IF 2.9 3区 物理与天体物理
Experimental Astronomy Pub Date : 2026-07-01 DOI: 10.1007/s10686-026-10065-9
Zeying Cai, Zhuo Li, Zhengwei Li, Jun Xiong, Liqiang Qi, Zhongliang Li, Congzhan Liu, Lin Li, Shuaiwei Li, Shun Xia, Guoxiang Deng, Na Gao, Qianqing Yin, Haoxuan Gao, Xin Huang, Le Kang, Tianxiang Chen
{"title":"Deposition and performance of depth-graded W/Si multilayers on silicon pore optics for the WXPT mission","authors":"Zeying Cai,&nbsp;Zhuo Li,&nbsp;Zhengwei Li,&nbsp;Jun Xiong,&nbsp;Liqiang Qi,&nbsp;Zhongliang Li,&nbsp;Congzhan Liu,&nbsp;Lin Li,&nbsp;Shuaiwei Li,&nbsp;Shun Xia,&nbsp;Guoxiang Deng,&nbsp;Na Gao,&nbsp;Qianqing Yin,&nbsp;Haoxuan Gao,&nbsp;Xin Huang,&nbsp;Le Kang,&nbsp;Tianxiang Chen","doi":"10.1007/s10686-026-10065-9","DOIUrl":"10.1007/s10686-026-10065-9","url":null,"abstract":"<div><p>The development of high-performance depth-graded multilayer coatings is critical for next-generation hard X-ray astronomical telescopes, such as the proposed Wide-band X-ray Polarization Telescope (WXPT) mission. This work focuses on the fabrication and performance evaluation of W/Si depth-graded multilayers designed for WXPT. The coatings were deposited using a custom-built linear direct-current magnetron sputtering system. Grazing-incidence X-ray reflectometry (XRR) and cross-sectional transmission electron microscopy (TEM) revealed consistently smooth interfaces with widths of approximately 0.3-0.4 nm, demonstrating exceptional layer uniformity and minimal cumulative roughening even over hundreds of layers. Atomic force microscopy confirmed the ultra-smooth surface morphology (RMS roughness &lt; 0.3 nm) of the final coatings. The critical impact of substrate roughness on multilayer reflectivity was quantitatively demonstrated. Most importantly, hard X-ray reflectivity measurements, both from a laboratory source and synchrotron radiation, showed excellent agreement with theoretical simulations assuming an interface width of <span>(sigma )</span> = 0.4 nm. The coatings achieved high reflectivity across a broad energy band (e.g.,  25% at 20-30 keV for a design optimized for <span>(0.3^circ )</span> incidence), successfully meeting the performance targets. These results establish a robust and reliable fabrication pathway for producing high-quality W/Si multilayers, marking a significant step towards their application in Silicon Pore Optics (SPO) for the WXPT mission.</p></div>","PeriodicalId":551,"journal":{"name":"Experimental Astronomy","volume":"62 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148380525","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
Exploring GRB localisation capability of proposed Daksha mission using coded mask imaging with its low-energy detectors 利用编码掩模成像及其低能探测器探索达克沙任务的GRB定位能力
IF 2.9 3区 物理与天体物理
Experimental Astronomy Pub Date : 2026-06-17 DOI: 10.1007/s10686-026-10058-8
Ashish K. Mandal, Santosh V. Vadawale, Varun Bhalerao
{"title":"Exploring GRB localisation capability of proposed Daksha mission using coded mask imaging with its low-energy detectors","authors":"Ashish K. Mandal,&nbsp;Santosh V. Vadawale,&nbsp;Varun Bhalerao","doi":"10.1007/s10686-026-10058-8","DOIUrl":"10.1007/s10686-026-10058-8","url":null,"abstract":"<div><p><i>Daksha</i> is a proposed high-energy transient mission for the study of electromagnetic counterparts of gravitational wave sources and gamma-ray bursts. Ideally, such studies need good localization of the GRBs along with their detection itself. In its current configuration, <i>Daksha</i> can localize short-duration bursts (T<span>(_{90})</span> &lt;1s) up to the fluence &gt;1<span>(times 10^{-7}~mathrm {erg~cm^{-2}})</span> to within 5<span>(^{circ })</span>—10<span>(^{circ })</span> using projection method. However, for rapid optical follow-up observations, the localization error radius should preferably be smaller than the field of view (FOV) of most optical telescopes, which is typically &lt; 1<span>(^{circ })</span>. Thus it would be greatly advantageous if the onboard localization by <i>Daksha</i> is within 1<span>(^{circ })</span>. One possibility to improve localization capability of <i>Daksha</i> is by employing coded mask imaging technique, which is being investigated in this work. <i>Daksha</i> carries three types of detectors mounted on the hemispherical dome of the payload; low-energy (LE), medium-energy (ME) and high-energy (HE) detectors. The LE and ME detectors are placed on the outside surface of the dome, while HE detectors are housed inside. The ME detector package (MEP) with its pixellated CZT detectors is a natural choice for attempting coded mask imaging, but it may lead to loss of sensitivity (by about a factor of five) and might require additional size and weight. In this context, here we explore the feasibility of using coded aperture mask (CAM) with the LE detector package (LEP), without substantially changing the size of the overall dome structure of <i>Daksha</i>. We consider a few candidate detectors, such as 1-D position sensitive silicon drift detectors (SDDs) as well as 2-D position sensitive X-ray Charge-Coupled Devices (CCDs), reported in the recent literature. We find that it is technically feasible to conceive a coded mask telescope (CMT) using these detectors that can provide sensitivity and localization accuracy of 4<span>(times 10^{-7}~mathrm {erg~cm^{-2}})</span> and <span>(sim 0.7^{circ })</span> respectively in the best case, and 8<span>(times 10^{-7}~mathrm {erg~cm^{-2}})</span> and <span>(sim 1.8^{circ })</span> respectively in the worst case.</p></div>","PeriodicalId":551,"journal":{"name":"Experimental Astronomy","volume":"62 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2026-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148261722","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
Observing bright pulsating white dwarfs with PLATO: A new window into the late stages of stellar evolution 用PLATO观察明亮的脉动白矮星:一个进入恒星演化后期的新窗口
IF 2.2 3区 物理与天体物理
Experimental Astronomy Pub Date : 2026-06-12 DOI: 10.1007/s10686-026-10060-0
Murat Uzundag, Alejandro H. Córsico, Nicholas Jannsen, Mukremin Kilic, Pierre Bergeron, Leandro G. Althaus, J. J. Hermes, Ingrid Pelisoli, Keaton J. Bell, Francisco C. De Gerónimo, Leila M. Calcaferro, Zsófia Bognár, Valérie Van Grootel, María E. Camisassa, Paulina Sowicka, Steven D. Kawaler, S. O. Kepler, Roberto Silvotti, Marcelo M. Miller Bertolami, Margarida Cunha
{"title":"Observing bright pulsating white dwarfs with PLATO: A new window into the late stages of stellar evolution","authors":"Murat Uzundag,&nbsp;Alejandro H. Córsico,&nbsp;Nicholas Jannsen,&nbsp;Mukremin Kilic,&nbsp;Pierre Bergeron,&nbsp;Leandro G. Althaus,&nbsp;J. J. Hermes,&nbsp;Ingrid Pelisoli,&nbsp;Keaton J. Bell,&nbsp;Francisco C. De Gerónimo,&nbsp;Leila M. Calcaferro,&nbsp;Zsófia Bognár,&nbsp;Valérie Van Grootel,&nbsp;María E. Camisassa,&nbsp;Paulina Sowicka,&nbsp;Steven D. Kawaler,&nbsp;S. O. Kepler,&nbsp;Roberto Silvotti,&nbsp;Marcelo M. Miller Bertolami,&nbsp;Margarida Cunha","doi":"10.1007/s10686-026-10060-0","DOIUrl":"10.1007/s10686-026-10060-0","url":null,"abstract":"<div><p>We present the scientific case for exploiting the capabilities of the PLATO mission to study bright pulsating white dwarfs across a wide spectral range, including hydrogen-deficient types (GW Vir and DBV stars) and hydrogen-rich classes (classical DAVs, pulsating extremely low-mass DA white dwarfs, and ultra-massive DA white dwarfs). PLATO’s exceptional photometric precision, long-duration continuous monitoring, and extensive sky coverage promise transformative advances in white dwarf asteroseismology. Our key objectives include probing the internal structure and chemical stratification of white dwarfs, detecting secular changes in pulsation modes over extended timescales, and discovering rare or previously unknown classes of pulsators. To assess feasibility, we constructed a sample of 650 white dwarf candidates (<span>(G le 17)</span>) identified within PLATO’s Southern LOPS2 field using the PLATO complementary science catalogue combined with <i>Gaia</i> DR3, and derived atmospheric parameters through photometric modeling. This sample comprises 118 DA white dwarfs (including 23 ZZ Ceti candidates), and 41 non-DAs (including 35 DBV candidates). Simulated observations with <span>PlatoSim</span> demonstrate that PLATO will detect white dwarf pulsation modes with amplitudes as low as <span>(sim )</span>0.1 mma, depending on stellar magnitude, observation duration, pixel location, and the number of contributing cameras. We provide detailed detection limits and visibility forecasts for known pulsators across a representative range of these parameters. Furthermore, we emphasize strong synergies with <i>Gaia</i> astrometry, TESS photometry, and targeted spectroscopic campaigns, which together will enable robust mode identification and detailed stellar modeling. Collectively, these efforts will unlock unprecedented insights into white dwarf origins, evolution and internal physics, and the fate of their planetary systems.</p></div>","PeriodicalId":551,"journal":{"name":"Experimental Astronomy","volume":"61 3","pages":""},"PeriodicalIF":2.2,"publicationDate":"2026-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148237294","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 characterization of 90 GHz band TESs in a dual-polarization dual-band pixel developed for AliCPT-1 AliCPT-1双偏振双带像元中90ghz频段苔丝的光学特性
IF 2.2 3区 物理与天体物理
Experimental Astronomy Pub Date : 2026-06-08 DOI: 10.1007/s10686-026-10061-z
Lin Zhu, Jiamin Sun, Xufang Li, Ye Chai, Yu Xu, Zhouhui Liu, Zhengwei Li, He Gao, Mengqi Jiang, Qinglei Xiu, Daikang Yan, Yaqiong Li, Shibo Shu, Congzhan Liu
{"title":"Optical characterization of 90 GHz band TESs in a dual-polarization dual-band pixel developed for AliCPT-1","authors":"Lin Zhu,&nbsp;Jiamin Sun,&nbsp;Xufang Li,&nbsp;Ye Chai,&nbsp;Yu Xu,&nbsp;Zhouhui Liu,&nbsp;Zhengwei Li,&nbsp;He Gao,&nbsp;Mengqi Jiang,&nbsp;Qinglei Xiu,&nbsp;Daikang Yan,&nbsp;Yaqiong Li,&nbsp;Shibo Shu,&nbsp;Congzhan Liu","doi":"10.1007/s10686-026-10061-z","DOIUrl":"10.1007/s10686-026-10061-z","url":null,"abstract":"<div><p>The Ali CMB Polarization Telescope (AliCPT-1) is a ground-based telescope aiming to measure the cosmic microwave background (CMB) polarization anisotropies using transition-edge sensor (TES) bolometers. In recent years, we have been developing polarization-sensitive, dichroic TES bolometers to populate the focal plane of AliCPT-1, which is designed to accommodate 19 detector modules. This paper focuses on the optical performance of a single pixel, laying the groundwork for the future kilopixel detector array. The optical characterization includes passband, optical efficiency, and polarization response. The measured passband is 87-122 GHz, shifted upward from the target range of 77–109 GHz. This shift may be a result of an overestimation of the interlayer’s dielectric permittivity. The optical efficiency is measured to be 57%, and the cross-polarization levels are 2.3% and 6.2% for the two orthogonal 90 GHz TES bolometers. These results demonstrate the potential for scaling our single-pixel design to large-format TES arrays.</p></div>","PeriodicalId":551,"journal":{"name":"Experimental Astronomy","volume":"61 3","pages":""},"PeriodicalIF":2.2,"publicationDate":"2026-06-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148236678","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
Simulation of proton-induced activation for low-Earth orbit high energy astrophysics missions 低地球轨道高能天体物理任务中质子诱导激活的模拟
IF 2.2 3区 物理与天体物理
Experimental Astronomy Pub Date : 2026-06-02 DOI: 10.1007/s10686-026-10059-7
Riccardo Campana
{"title":"Simulation of proton-induced activation for low-Earth orbit high energy astrophysics missions","authors":"Riccardo Campana","doi":"10.1007/s10686-026-10059-7","DOIUrl":"10.1007/s10686-026-10059-7","url":null,"abstract":"<div><p>Proton-induced activation represents a major source of instrumental background for high-energy astrophysics missions in low-Earth orbit, where trapped protons, particularly during transits within the South Atlantic Anomaly region, irradiate spacecraft materials and generate radioactive isotopes. Direct Monte Carlo simulations of activation and of the ensuing decays are computationally inefficient, due to the low probability of nuclide production and the large number of decay events required for sufficient statistical accuracy. In this paper we provide a new implementation of an efficient three-step algorithm that decouples isotope production, radioactive-decay evolution, and background synthesis, enabling rapid reconstruction of activation-induced background for arbitrary irradiation histories. The method combines Geant4-based identification of all radioisotopes produced by monochromatic proton irradiations, numerical solutions of the Bateman equations for linearized decay chains, and simulation of the detector response to each isotope decay emissions. The approach greatly reduces the computational cost while maintaining accuracy, as demonstrated through validation against direct simulations, which show excellent agreement over many orders of magnitude in activity and time. This method is applied to two representative case studies: HERMES and eXTP/LAD and WFM, covering different detector technologies and orbital configurations. The presented framework enables fast exploration of design and operational scenarios (e.g., orbit selection, radiation models, or duty cycles) and is well suited for background budgeting and optimization of future high-energy space missions.</p></div>","PeriodicalId":551,"journal":{"name":"Experimental Astronomy","volume":"61 3","pages":""},"PeriodicalIF":2.2,"publicationDate":"2026-06-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10686-026-10059-7.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148172142","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
The Blurring Interference Seeing Motion Monitor (BLISMM): a compact instrument for simultaneous measurement of (r_0), per-frame (tau _0(n)), and (theta _0) without wind speed measurement 模糊干扰视动监测器(BLISMM):一个紧凑的仪器,同时测量(r_0),每帧(tau _0(n))和(theta _0)没有风速测量
IF 2.2 3区 物理与天体物理
Experimental Astronomy Pub Date : 2026-05-29 DOI: 10.1007/s10686-026-10057-9
B. Trégon, G. Nicque, W. Benharbone, M. Lavaud, A-R. Camboulives
{"title":"The Blurring Interference Seeing Motion Monitor (BLISMM): a compact instrument for simultaneous measurement of (r_0), per-frame (tau _0(n)), and (theta _0) without wind speed measurement","authors":"B. Trégon,&nbsp;G. Nicque,&nbsp;W. Benharbone,&nbsp;M. Lavaud,&nbsp;A-R. Camboulives","doi":"10.1007/s10686-026-10057-9","DOIUrl":"10.1007/s10686-026-10057-9","url":null,"abstract":"<div><p>We present the BLISMM (Blurring Interference Seeing Motion Monitor), a compact pupil-plane mask instrument measuring simultaneously the Fried parameter <span>(r_0)</span>, the per-frame coherence time <span>(tau _0(n))</span>, and the isoplanatic angle <span>(theta _0)</span> from a single video sequence on a bright star. A three-aperture mask combines a DIMM channel for <span>(r_0)</span> [21], a Fizeau interferometric channel for <span>(tau _0(n))</span>, and an aperture scintillation channel for <span>(theta _0)</span> [5]. The central contribution is a per-frame expression for <span>(tau _0(n))</span> derived directly from the contrast degradation of Fizeau fringes within individual exposures, without requiring knowledge of the atmospheric wind speed profile. Unlike the GDIMM [1], which estimates <span>(tau _0)</span> from angle-of-arrival statistics leading to an effective wind speed, or the SHIMM [18], which derives <span>(tau _0)</span> from the power spectrum of wavefront defocus over temporal sequences, the BLISMM provides an instantaneous <span>(tau _0(n))</span> at frame rate. On-sky validation at two French observatories (2014 and 2023) yields a linear correlation slope <span>(=1.00)</span> and <span>(R^2=0.98)</span> over 2033 frames between the fringe-based <span>(tau _0(n))</span> and an independent <span>(tau _0)</span> estimate. Mean values from the 2023 campaign: <span>(r_0=55)</span> mm (seeing <span>(approx 2.4'')</span> at 656 nm), <span>(tau _0(n)=1.57)</span> ms, <span>(theta _0=9.75'')</span>. The per-frame <span>(tau _0(n))</span> output enables real-time frame selection for lucky imaging without wind speed data.</p></div>","PeriodicalId":551,"journal":{"name":"Experimental Astronomy","volume":"61 3","pages":""},"PeriodicalIF":2.2,"publicationDate":"2026-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148173380","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
Design of VDIF formatter/deformatter and network interfaces for real-time VLBI 实时VLBI的VDIF格式化/反格式化和网络接口设计
IF 2.2 3区 物理与天体物理
Experimental Astronomy Pub Date : 2026-05-19 DOI: 10.1007/s10686-026-10056-w
Wei Yu
{"title":"Design of VDIF formatter/deformatter and network interfaces for real-time VLBI","authors":"Wei Yu","doi":"10.1007/s10686-026-10056-w","DOIUrl":"10.1007/s10686-026-10056-w","url":null,"abstract":"<div><p>In a very long baseline interferometry (VLBI) system, multiple radio telescopes far apart observe the same radio source simultaneously and then transmit the observed data from digital backends to a correlator. This paper describes a data transmission system designed for the digital backends and the hardware correlator based on field programmable gate array (FPGA), which can support real-time VLBI (e-VLBI) observations with the existing Internet. The data transmission system includes four parts: the VLBI data interchange format (VDIF) formatter, the network transmission interface, the VDIF deformatter and the network receiving interface. Where, the first two parts are embedded in the digital backends, while the latter two parts are embedded in the hardware correlator. Experimental results and real observations demonstrate that the functions of the VDIF formatter/deformatter are correct, and the throughput performance of the network transmission/receiving interfaces can meet the requirements of use.</p></div>","PeriodicalId":551,"journal":{"name":"Experimental Astronomy","volume":"61 3","pages":""},"PeriodicalIF":2.2,"publicationDate":"2026-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10686-026-10056-w.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148008598","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
Methodological refinement of the submillimeter galaxy cross-correlation function measurements and their uncertainty estimation 亚毫米星系互相关函数测量方法的改进及其不确定度估计
IF 2.2 3区 物理与天体物理
Experimental Astronomy Pub Date : 2026-04-27 DOI: 10.1007/s10686-026-10055-x
Joaquín González-Nuevo, Laura Bonavera, Marcos M. Cueli, David Crespo, Jose Manuel Casas, Rebeca Fernández-Fernández
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