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Related papers: Temporal offsets among Solar activity indicators

200 papers

We investigate spatio-temporal evolution of high-degree acoustic mode frequencies of the Sun and the surface magnetic activity, over the course of multiple solar cycles, to improve our understanding of the connection between the solar…

Solar and Stellar Astrophysics · Physics 2023-12-20 Mackenzie A. Baird , Sushanta C. Tripathy , Kiran Jain

The Sun has long been considered a constant star, to the extent that its total irradiance was termed the solar constant. It required radiometers in space to detect the small variations in solar irradiance on timescales of the solar rotation…

Solar and Stellar Astrophysics · Physics 2015-06-11 Sami K. Solanki , Yvonne C. Unruh

Interstellar signals might be intermittent for many reasons, such as targeted sequential transmissions, or isotropic broadcasts that are not on continuously, or many other reasons. The time interval between such signals would be important,…

Instrumentation and Methods for Astrophysics · Physics 2021-10-26 Robert H. Gray

It is well known that the observed amplitude of solar oscillations is lower in sunspots than in quiet regions of the Sun. We show that this local reduction in oscillation amplitudes combined with the phase-speed filtering procedure in…

Astrophysics · Physics 2009-11-11 S. P. Rajaguru , A. C. Birch , T. L. Duvall , M. J. Thompson , J. Zhao

We describe the defining observations of the solar cycle that provide constraints for the dynamo processes operating within the Sun. Specifically, we report on the following topics: historical sunspot numbers and revisions; active region…

Solar and Stellar Astrophysics · Physics 2023-09-29 Aimee Norton , Rachel Howe , Lisa Upton , Ilya Usoskin

Irradiance variability has been monitored from space for more than two decades. Even if data are coming from different sources, it is well established that a temporal variability exists which can be set to as approximately 0.1%, in phase…

Astrophysics · Physics 2009-11-11 J. P. Rozelot , S. Lefebvre , S. Pireaux , A. Ajabshirizadeh

The torsional oscillation is a well established observational fact and there are theoretical attempts for its description but no final solution has yet been accepted. One of the possible candidates for its cause is the presence of sunspots…

Solar and Stellar Astrophysics · Physics 2014-01-13 J. Muraközy , A. Ludmány

The theory of stellar structure can be used to identify the most plausible mechanisms for the irradiance variations associated with the solar cycle. Changes in surface emissivity, i.e. the reduced cooling in spots and enhanced emission by…

Astrophysics · Physics 2007-05-23 H. C. Spruit

We argue that earth's short-term temperature anomalies and the solar flare intermittency are linked. The analysis is based upon the study of the scaling of both the spreading and the entropy of the diffusion generated by the fluctuations of…

Statistical Mechanics · Physics 2009-11-10 Nicola Scafetta , Bruce J. West

The present paper reviews results derived from statistical studies on solar activity indices. The prolonged minimum phase of cycle 23 raised the question of peculiarities inherent in cycle 23. The most important solar activity index is the…

Solar and Stellar Astrophysics · Physics 2010-02-03 M. Temmer

The Sun provides an excellent natural laboratory for nonlinear phenomena. We use motions of magnetic bright points on the solar surface, at the smallest scales yet observed, to study the small scale dynamics of the photospheric plasma. The…

Astrophysics · Physics 2009-11-06 J. K. Lawrence , A. C. Cadavid , A. Ruzmaikin , T. E. Berger

The solar northern and southern hemispheres exhibit differences between the intensities and time profiles of the activity cycles. The time variation of these properties has been studied in a previous article on the data of Cycles 12-23. The…

Solar and Stellar Astrophysics · Physics 2016-07-29 Judit Muraközy

Temporal resolution of visual information processing is thought to be an important factor in predator-prey interactions, shaped in the course of evolution by animals' ecology. Here I show that light can be considered to have a dual role of…

Neurons and Cognition · Quantitative Biology 2019-10-25 Bartosz Jura

The total amount of solar irradiance falling on the earth's surface is an important area of study amongst the photo-voltaic (PV) engineers and remote sensing analysts. The received solar irradiance impacts the total amount of generated…

Instrumentation and Methods for Astrophysics · Physics 2018-04-23 Shilpa Manandhar , Soumyabrata Dev , Yee Hui Lee , Yu Song Meng

We show that while the Fourier transform can figure only an "intensity" of a periodic signal, there is an additional information embedded, which is a "coherence" of the signal. Supposing that the periodicity is reflected only on the…

Solar and Stellar Astrophysics · Physics 2022-02-07 Kim Chol-jun

We present evidence of hitherto undiscovered global-scale oscillations in the near-surface shear layer of the Sun. These oscillations are seen as large scale variations of radial shear in both the zonal and meridional flows relative to…

Solar and Stellar Astrophysics · Physics 2023-07-05 Richard S. Bogart , Charles S. Baldner , Sarbani Basu , Rachel Howe , Maria Cristina Rabello Soares

This article reviews some of the leading results obtained in solar dynamo physics by using temporal oscillator models as a tool to interpret observational data and dynamo model predictions. We discuss how solar observational data such as…

Solar and Stellar Astrophysics · Physics 2014-07-21 Ilídio Lopes , Dário Passos , Melinda Nagy , Kristof Petrovay

In helioseismology, there is a well-known offset between observed and computed oscillation frequencies. This offset is known to arise from improper modeling of the near-surface layers of the Sun, and a similar effect must occur for models…

Astrophysics · Physics 2009-11-13 Hans Kjeldsen , Timothy R. Bedding , Joergen Christensen-Dalsgaard

Context. In local helioseismology, the travel times of acoustic waves propagating in opposite directions along the same meridian inform us about horizontal flows in the north-south direction. The longitudinal averages of the north-south…

Solar and Stellar Astrophysics · Physics 2022-08-31 Paul-Louis Poulier , Zhi-Chao Liang , Damien Fournier , Laurent Gizon

The correlation scale and the Taylor scale are evaluated for interplanetary magnetic field fluctuations from two-point, single time correlation function using the Advanced Composition Explorer (ACE), Wind, and Cluster spacecraft data during…

Space Physics · Physics 2020-08-20 G. Zhou , H. -Q. He , W. Wan