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High-precision nonlocal temporal correlation identification in the entangled photon pairs is critical to measure the time offset between remote independent time scales for many quantum information applications. The first nonlocal…

Quantum Physics · Physics 2021-02-03 Runai Quan , Ruifang Don , Xiao Xiang , Baihong Li , Tao Liu , Shougang Zhang

In a previous paper, I described a new way of determining the high-latitude solar rotation rate statistically from space-time maps of polar faculae observed in the 6767 \r{A} continuum by the Michelson Doppler Interferometer (MDI) on the…

Solar and Stellar Astrophysics · Physics 2025-02-04 Neil R. Sheeley

The Sun's internal rotation {\Omega}(r,{\Theta}) has previously been measured using helioseismology techniques and found to be a complex function of co-latitude, {\theta}, and radius, r. From helioseismology and observations of apparently…

Solar and Stellar Astrophysics · Physics 2017-02-08 Ian Cunnyngham , Marcelo Emilio , Jeff Kuhn , Isabelle Scholl , Rock Bush

The global rotational profile of the solar atmosphere and its variation at different layers, although crucial for a comprehensive understanding of the dynamics of the solar magnetic field, has been a subject to contradictory results…

Tracking many vehicles in wide coverage aerial imagery is crucial for understanding events in a large field of view. Most approaches aim to associate detections from frame differencing into tracks. However, slow or stopped vehicles result…

Computer Vision and Pattern Recognition · Computer Science 2016-03-30 Bor-Jeng Chen , Gerard Medioni

The measurement of Doppler velocities in spectroscopic solar observations requires a reference for the local frame of rest. The rotational and radial velocities of the Earth and the rotation of the Sun introduce velocity offsets in the…

Solar and Stellar Astrophysics · Physics 2015-05-27 Jaime de la Cruz Rodríguez , Dan Kiselman , Mats Carlsson

We aim to gain insight into the effect of network and faculae on solar irradiance from their apparent intensity. Taking full-disc observations from the Solar Dynamics Observatory, we examined the intensity contrast of network and faculae in…

Solar and Stellar Astrophysics · Physics 2021-02-19 K. L. Yeo , N. A. Krivova

The internal rotation of low mass stars all along their evolution is of primary interest when studying their rotational dynamics, internal mixing and magnetic fields generation. In this context, helio- and asteroseismology probe angular…

Solar and Stellar Astrophysics · Physics 2016-09-05 Delphine Hypolite , Stéphane Mathis , Michel Rieutord

We present a comprehensive study of one method for measuring various parameters of global modes of oscillation of the Sun. Using velocity data taken by the Michelson Doppler Imager (MDI), we analyze spherical harmonic degrees l <= 300. Both…

Solar and Stellar Astrophysics · Physics 2015-11-18 Tim Larson , Jesper Schou

A very slight rotation-induced latitudinal temperature variation (presumably on the order of several Kelvin) on the solar surface is theoretically expected. While recent high-precision solar brightness observations reported its detection,…

Solar and Stellar Astrophysics · Physics 2017-08-30 Y. Takeda , S. UeNo

The stochastic order redshift technique (SORT) is a simple, efficient, and robust method to improve cosmological redshift measurements. The method relies upon having a small ($\sim$10 per cent) reference sample of high-quality redshifts.…

Cosmology and Nongalactic Astrophysics · Physics 2022-05-25 James Kakos , Joel R. Primack , Aldo Rodriguez-Puebla , Nicolas Tejos , L. Y. Aaron Yung , Rachel S. Somerville

Comparing solar and stellar brightness variations is hampered by the difference in spectral passbands used in observations as well as by the possible difference in the inclination of their rotation axes from the line of sight. We calculate…

Solar and Stellar Astrophysics · Physics 2020-07-01 N. -E. Nèmec , E. Işık , A. I. Shapiro , S. K. Solanki , N. A. Krivova , Y. Unruh

The quasar target selection for the upcoming survey of the Dark Energy Spectroscopic Instrument (DESI) will be fixed for the next five years. The aim of this work is to validate the quasar selection by studying the impact of imaging…

Helioseismology has revealed that the angular velocity of the Sun increases with depth in the outermost 35 Mm of the Sun. Recently, we have shown that the logarithmic radial gradient ($\rm d\ln\Omega/\rm d\ln r $) in the upper 10~Mm is…

Solar and Stellar Astrophysics · Physics 2016-11-02 Atefeh Barekat , Jesper Schou , Laurent Gizon

We use autocorrelation to investigate evolution in flow fields inferred by applying Fourier Local Correlation Tracking (FLCT) to a sequence of high-resolution (0.3 \arcsec), high-cadence ($\simeq 2$ min) line-of-sight magnetograms of NOAA…

Solar and Stellar Astrophysics · Physics 2015-05-30 Brian T. Welsch , Kanya Kusano , Tetsuya T. Yamamoto , K. Muglach

The observed large-scale structure of the Universe is not a direct measure on the underlying distribution of matter. These observations are subtly distorted by gravitational lensing effects, which leave imprints on the statistical…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-01 T. Sinde , J. Fonseca

The variation in area of quiet magnetic network measured over the sunspot cycle should modulate the spatially averaged photospheric temperature gradient, since temperature declines with optical depth more gradually in magnetic flux tube…

Solar and Stellar Astrophysics · Physics 2017-01-25 Serena Criscuoli , Peter Foukal

Photospheric horizontal velocity fields play essential roles in the formation and evolution of numerous solar activities. Various methods for estimating the horizontal velocity field have been proposed in the past. Aiming at the highest…

Solar and Stellar Astrophysics · Physics 2026-01-27 Quan Xie , Jiajia Liu , Robert Erdélyi , Yuming Wang

Data reduction techniques published so far for the CoRoT N2 data product were targeted primarily on the detection of extrasolar planets. Since the whole dataset has been released, specific algorithms are required to process the lightcurves…

Instrumentation and Methods for Astrophysics · Physics 2015-03-20 Joerg Weingrill

Lidars are depth measuring sensors widely used in autonomous driving and augmented reality. However, the large volume of data produced by lidars can lead to high costs in data storage and transmission. While lidar data can be represented as…

Image and Video Processing · Electrical Eng. & Systems 2022-06-07 Xuanyu Zhou , Charles R. Qi , Yin Zhou , Dragomir Anguelov