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Inter-channel mis-synchronisation can be a limiting factor to the time resolution of high performance timing detectors with multiple readout channels and independent electronics units. In these systems, time calibration methods employed…

Instrumentation and Detectors · Physics 2026-03-03 S. Abe , H. Alarakia-Charles , I. Alekseev , C. Alt , T. Arai , T. Arihara , S. Arimoto , A. M. Artikov , Y. Awataguchi , N. Babu , V. Baranov , G. Barr , D. Barrow , L. Bartoszek , L. Bernardi , L. Berns , S. Bhattacharjee , A. V. Boikov , A. Blanchet , A. Blondel , A. Bonnemaison , S. Bordoni , M. H. Bui , T. H. Bui , F. Cadoux , S. Cap , A. Cauchois , J. Chakrani , P. S. Chong , A. Chvirova , P. Collard , M. Danilov , C. Davis , V. Davouloury , Yu. I. Davydov , A. Dergacheva , C. Domangue , D. Douqa , T. A. Doyle , O. Drapier , A. Eguchi , J. Elias , G. Erofeev , Y. Favre , D. Fedorova , S. Fedotov , D. Ferlewicz , Y. Fujii , R. Fujita , Y. Furui , F. Gastaldi , A. Gendotti , A. Germer , L. Giannessi , C. Giganti , V. Glagolev , R. Guillaumat , G. Ha , N. C. Hastings , I. Heitkamp , J. Hu , C. Husi , A. K. Ichikawa , T. H. Ishida , A. Izmaylov , K. Iwamoto , M. Jakkapu , C. Jesús-Valls , J. Y. Ji , P. Jonsson , C. K. Jung , H. Kakuno , V. S. Kasturi , M. Kawaue , P. T. Keener , M. Khabibullin , N. V. Khomutov , A. Khotjantsev , T. Kikawa , H. Kikutani , N. V. Kirichkov , A. Klustová , H. Kobayashi , T. Kobayashi , L. Koch , S. Kodama , A. O. Kolesnikov , M. Kolupanova , A. Korzenev , T. Koto , Y. Kudenko , S. Kuribayashi , T. Kutter , M. Lachat , K. Lachner , M. Lamers James , D. Last , N. Latham , M. Lawe , T. A. Le , D. Leon Silverio , B. Li , W. Li , C. Lin , M. Louzir , T. Lux , K. K. Mahtani , S. Manly , D. A. Martinez Caicedo , N. Mashin , T. Matsubara , C. Mauger , K. S. McFarland , C. McGrew , J. McKean , A. Mefodiev , E. Miller , O. Mineev , A. Minamino , A. L. Moreno , A. Muñoz , T. Nakadaira , K. Nakagiri , T. Nakaya , J. Nanni , L. Nicolas , A. D. Nguyen , D. T. Nguyen , H. Nguyen , V. Nguyen , E. Noah Messomo , T. Nosek , H. M. O'Keeffe , T. Ogawa , W. Okinaga , L. Osu , V. Paolone , G. Pelleriti , L. Pickering , M. A. Ramírez , M. Reh , G. Reina , C. Riccio , S. Roth , A. Rubbia , F. Saadi , K. Sakashita , N. Sallin , S. Samani , F. Sanchez , T. Schefke , C. Schloesser , D. Sgalaberna , A. Shaikovskiy , A. Shvartsman , Y. Shiraishi , N. Shvarev , N. Skrobova , D. Smyczek , M. Smy , A. Speers , D. Svirida , M. Ta , S. Tairafune , M. Tani , H. Tanigawa , A. Teklu , S. Tereshchenko , V. V. Tereshchenko , T. Thaiduc , T. Tsushima , M. Tzanov , Y. Uchida , I. I. Vasilyev , E. Villa , T. Vladisavljevic , D. Wakabayashi , H. Wallace , A. Weber , N. Whitney , C. Wret , Y. Xu , Y. Yang , N. Yershov , A. J. P. Yrey , M. Yokoyama , Y. Yoshimoto , X. Y. Zhao , H. Zheng , H. Zhong , T. Zhu , E. D. Zimmerman , M. Zito

We present recent improvements in polarization analysis with the INTEGRAL SPI data. The SPI detector plane consists of 19 independent Ge crystals and can operate as a polarimeter. The anisotropy characteristics of Compton diffusions can…

Instrumentation and Methods for Astrophysics · Physics 2015-06-15 M. Chauvin , J. P. Roques , D. J. Clark , E. Jourdain

By measuring photoelectron tracks, the gas pixel detectors of the Imaging X-ray Polarimetry Explorer satellite provide estimates of the photon detection location and its electric vector position angle (EVPA). However, imperfections in…

Instrumentation and Methods for Astrophysics · Physics 2024-09-24 Jack T. Dinsmore , Roger W. Romani

Customized digital backends for Very Long Baseline Interferometry (VLBI) are critical components for radio astronomy observatories. There are several serialized products such as the Digital Baseband Converter (DBBC), Reconfigurable Open…

Instrumentation and Methods for Astrophysics · Physics 2025-02-24 Jiyun Li , Renjie Zhu , Shaoguang Guo , Ping Rui , Zhijun Xu

Next generation radio telescope arrays are being designed and commissioned to accurately measure polarized intensity and rotation measures across the entire sky through deep, wide-field radio interferometric surveys. Radio interferometer…

Instrumentation and Methods for Astrophysics · Physics 2017-08-02 P. Jagannathan , S. Bhatnagar , U. Rau , A. R. Taylor

Polarimetric imaging has been applied in a growing number of applications in robotic vision (ex. underwater navigation, glare removal, de-hazing, object classification, and depth estimation). One can find on the market RGB Polarization…

Computer Vision and Pattern Recognition · Computer Science 2022-08-30 Joaquin Rodriguez , Lew Lew-Yan-Voon , Renato Martins , Olivier Morel

We consider the problem of multifrequency VLBA image synthesis and spectral-index mapping for active galactic nuclei related to the necessity of taking into account the frequency-dependent image shift. We describe our generalized…

Cosmology and Nongalactic Astrophysics · Physics 2010-06-29 Anisa T. Bajkova , Alexander B. Pushkarev

This paper addresses the challenges of wideband signal beamforming in radar systems and proposes a new calibration method. Due to operating conditions, the frequency dependent characteristics of the system can be changed, and amplitude,…

Signal Processing · Electrical Eng. & Systems 2023-06-27 Hyung-Woo Kim , Jin-woo Kim , Jin-ha Kim , JaeYoung Choi , Sangpyo Hong , Byungkwan Kim

We have studied the implications of high sensitivity polarization measurements of objects from the WMAP point source catalogue made using the VLA at 8.4, 22 and 43 GHz. The fractional polarization of sources is almost independent of…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 R. A. Battye , I. W. A. Browne , M. W. Peel , N. J. Jackson , C. Dickinson

One major goal in fast radio burst science is to detect fast radio bursts (FRBs) over a wide field of view without sacrificing the angular resolution required to pinpoint them to their host galaxies. Wide-field detection and localization…

We demonstrate that at 1.4 GHz the combined response of sources detected serendipitously in deep, wide-field VLBI images is sufficient to permit self-calibration techniques to be employed. This technique of "full-beam" VLBI self-calibration…

Astrophysics · Physics 2007-05-23 M. A. Garrett , J. M. Wrobel , R. Morganti

We present MeqSilhouette v2.0 (MeqSv2), a fully polarimetric, time-and frequency-resolved synthetic data generation software for simulating millimetre (mm) wavelength very long baseline interferometry (VLBI) observations with heterogeneous…

Active Galactic Nuclei (AGNs) observed with the technique of very long baseline interferometry (VLBI) are used as fiducial references on the sky to precisely measure the shape and orientation of the Earth. Their positions form a celestial…

Astrophysics of Galaxies · Physics 2025-01-31 Ming Hui Xu , Patrick Charlot

We present a method based on Mueller calculus to calibrate linear polarimetric observations. The key advantages of the proposed way of calibration are: (1) that it can be implemented in a data reduction pipeline, (2) that it is possible to…

Astrophysics · Physics 2009-11-13 Franco Joos , Esther Buenzli , Hans Martin Schmid , Christian Thalmann

Very Long Baseline Interferometry is capable of measuring the gravitational delay caused by the Sun and planet gravitational fields. The post-Newtonian parameter $\gamma$ is now estimated with accuracy of $\sigma_{\gamma}=2\cdot 10^{-4}$…

Instrumentation and Methods for Astrophysics · Physics 2013-11-04 Anastassia Girdiuk , Oleg Titov

X-ray polarimetry, based on Gas Pixel Detectors (GPDs), have reached a high level of maturity with the Imaging X-ray Polarimeter Explorer (IXPE) leading to the first ever spatially resolved polarimetric measures. However, being this a new…

Instrumentation and Methods for Astrophysics · Physics 2023-04-05 N. Bucciantini , N. Di Lalla , R. W. R. Romani , S. Silvestri , M. Negro , L. Baldini , A. F. Tennant , A. Manfreda

We present the results of a survey of radio continuum sources near the Galactic plane using the Very Long Baseline Array (VLBA). Our observations are designed to identify compact extragalactic sources of milliarcsecond size that can be used…

Astrophysics of Galaxies · Physics 2015-05-27 K. Immer , A. Brunthaler , M. J. Reid , A. Bartkiewicz , Y. K. Choi , K. M. Menten , L. Moscadelli , A. Sanna , Y. W. Wu , Y. Xu , B. Zhang , X. W. Zheng

Atmospheric propagation errors are a main constraint on the accuracy of Very Long Baseline Interferometry (VLBI) astrometry. For relative astrometry, differential techniques can mitigate these errors, but their effectiveness diminishes with…

Instrumentation and Methods for Astrophysics · Physics 2025-05-26 Jingdong Zhang , Bo Zhang , Shuangjing Xu , Maria J. Rioja , Richard Dodson , Xiaofeng Mai , Oleg Titov

The response of the Advanced LIGO interferometers is known to vary with time [arXiv:1608.05134]. Accurate calibration of the interferometers must therefore track and compensate for temporal variations in calibration model parameters. These…

Instrumentation and Methods for Astrophysics · Physics 2023-01-11 Madeline Wade , Aaron D. Viets , Theresa Chmiel , Madeline Stover , Leslie Wade

The Planck Low Frequency Instrument will recover polarization by differencing the outputs from radiometers sensitive to orthogonal polarizations. We contrast the systematic errors that afflict such a system with those that affect…

Astrophysics · Physics 2014-10-13 J. P. Leahy , V. Yurchenko , Morag Hastie , M. Bersanelli , N. Mandolesi