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We introduce a vector atomic magnetometer that employs a fast-rotating magnetic field applied to a pulsed $^{87}$Rb scalar atomic magnetometer. This approach enables simultaneous measurements of the total magnetic field and its two polar…

Quantum Physics · Physics 2025-02-07 Tao Wang , Wonjae Lee , Mark Limes , Tom Kornack , Elizabeth Foley , Michael Romalis

(Abridged): We assess the statistical errors in estimating the parameters of non-spinning black-hole binaries using ground-based gravitational-wave detectors. While past assessments were based on only the inspiral/ring-down pieces of the…

General Relativity and Quantum Cosmology · Physics 2009-11-06 P. Ajith , Sukanta Bose

We propose a novel paradigm to vector magnetometry based on machine learning. Unlike conventional schemes where one measured signal explicitly connects to one parameter, here we encode the three-dimensional magnetic-field information in the…

Instrumentation and Detectors · Physics 2023-10-04 Xin Meng , Youwei Zhang , Xichang Zhang , Shenchao Jin , Tingran Wang , Liang Jiang , Liantuan Xiao , Suotang Jia , Yanhong Xiao

We estimate disc-averaged RV variations of the Sun over the last magnetic cycle, from the single Fe I line observed by SDO/HMI, using a physical model for rotationally modulated magnetic activity that was previously validated against…

Active regions (ARs) appear in the solar atmosphere as a consequence of the emergence of magnetic flux-ropes (FR). In this study, we use Bayesian methods to analyze line-of-sight magnetograms of emerging ARs. We employ a FR model consisting…

Solar and Stellar Astrophysics · Physics 2024-05-21 Mariano Poisson , Marcelo López Fuentes , Cristina H. Mandrini , Pascal Démoulin , Francisco Grings

Many experimental efforts are striving to provide deep maps of the cosmic microwave background (CMB) to shed light on key questions in modern cosmology. The primary science goal for some of these experiments is to further constrain the…

Instrumentation and Methods for Astrophysics · Physics 2024-08-14 Rustam Balafendiev , Thomas Gascard , Jon E. Gudmundsson

A fraction of the XMM-Newton/EPIC FOV is obscured by the dysfunctional (i.e. bad) pixels. The fraction varies between different EPIC instruments in a given observation. These complications affect the analysis of extended X-ray sources…

Instrumentation and Methods for Astrophysics · Physics 2021-03-03 J. Nevalainen , I. Valtchahov , R. D. Saxton , S. Molendi

A physical magnetic field has a divergence of zero. Numerical error in constructing a model field and computing the divergence, however, introduces a finite divergence into these calculations. A popular metric for measuring divergence is…

Solar and Stellar Astrophysics · Physics 2021-04-05 S. A. Gilchrist , K. D. Leka , G. Barnes , M. S. Wheatland , M. L. DeRosa

This paper contributes to the growing body of research on deep learning methods for solar flare prediction, primarily focusing on highly overlooked near-limb flares and utilizing the attribution methods to provide a post hoc qualitative…

Machine Learning · Computer Science 2023-09-27 Chetraj Pandey , Rafal A. Angryk , Berkay Aydin

The zero point of measured photospheric Doppler shifts is uncertain for at least two reasons: instrumental variations (from, e.g., thermal drifts), and the convective blueshift, a known correlation between intensity and upflows. Calibrated…

Solar and Stellar Astrophysics · Physics 2015-06-03 Brian T. Welsch , George H. Fisher , Xudong Sun

Cardiovascular magnetic resonance (CMR) imaging has become a modality with superior power for the diagnosis and prognosis of cardiovascular diseases. One of the essential basic quality controls of CMR images is to investigate the complete…

Image and Video Processing · Electrical Eng. & Systems 2024-10-29 Shahabedin Nabavi , Mohammad Hashemi , Mohsen Ebrahimi Moghaddam , Ahmad Ali Abin , Alejandro F. Frangi

Scanning Laser Doppler Vibrometer (SLDV) measurements are affected by sensor head vibrations as if they are vibrations of the target surface itself. This paper presents practical correction schemes to solve this important problem. The study…

Instrumentation and Detectors · Physics 2020-06-22 Ben J. Halkon , Steve J. Rothberg

Comparisons of solar magnetic-field measurements made in different spectral lines are very important, especially in those lines in which observations have a long history or(and) specific diagnostic significance. The spectral lines FeI 523.3…

Solar and Stellar Astrophysics · Physics 2009-12-18 Michael L. Demidov , Horst Balthasar

The Full-disk magnetograph is a main scientific payload onboard the Advanced Space based Solar Observatory (ASO-S/FMG) that through Stokes parameter observation to measures the vector magnetic field. The accuracy of magnetic-field values is…

Solar and Stellar Astrophysics · Physics 2023-12-04 S. Liu , J. T. Su , X. Y. Bai , Y. Y. Deng , J. Chen , Y. L. Song , X. F. Wang , H. Q. Xu , X. Yang

Existing oriented object detection methods commonly use metric AP$_{50}$ to measure the performance of the model. We argue that AP$_{50}$ is inherently unsuitable for oriented object detection due to its large tolerance in angle deviation.…

Computer Vision and Pattern Recognition · Computer Science 2024-04-09 Ying Zeng , Yushi Chen , Xue Yang , Qingyun Li , Junchi Yan

An azimuthally electric-polarized vector beam (APB), with a polarization vortex, has a salient feature that it contains a magnetic-dominant region within which electric field ideally has a null while longitudinal magnetic field is maximum.…

Optics · Physics 2016-11-03 Mehdi Veysi , Caner Guclu , Filippo Capolino

In this paper we test the astrometric precision of VLT/FORS2 observations using a serie of CCD frames taken in Galactic bulge area. A special reduction method based on symmetrization of reference fields was used to reduce the atmospheric…

Astrophysics · Physics 2009-11-11 Petro F. Lazorenko

Weak gravitational lensing measurements based on photometry are limited by shape noise, the variance in the unknown unlensed orientations of the source galaxies. If the source is a disk galaxy with a well-ordered velocity field, however,…

Cosmology and Nongalactic Astrophysics · Physics 2021-01-08 David Wittman , Matthew Self

This paper presents experimental results that allow for the performance evaluation of a straight-line reference alignment system based on pseudo-nondiffracting Layer beams. Sensors, developed specifically for this system, feature four…

Magnetography using magnetic sensitive lines is regarded traditionally as the main instrument for measuring the magnetic field of the whole Sun. Full polarized Stockes parameters ($I$, $Q$, $U$, $V$) observed can be used to deduce the…

Solar and Stellar Astrophysics · Physics 2022-01-19 S. Liu , J. T. Su , X. Y. Bai , Y. Y Deng , J. Chen , Y. L. Song , X. F. Wang , H. Q. Xu , X. Yang