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Related papers: Inversions for Deep Solar Meridional Flow Using Sp…

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Accurate inference of solar meridional flow is of crucial importance for the understanding of solar dynamo process. Wave travel times, as measured on the surface, will change if the waves encounter perturbations e.g. in the sound speed or…

Solar and Stellar Astrophysics · Physics 2018-08-15 K. Mandal , S. M. Hanasoge , S. P. Rajaguru , H. M. Antia

Accurate measurements of deep solar meridional flow are of vital interest for understanding the solar dynamo. In this paper, we validate a recently developed method for obtaining sensitivity functions (kernels) for travel-time measurements…

Solar and Stellar Astrophysics · Physics 2017-04-19 Vincent G. A. Böning , Markus Roth , Jason Jackiewicz , Shukur Kholikov

Meridional flow is thought to play a very important role in the dynamics of the solar convection zone; however, because of its relatively small amplitude, precisely measuring it poses a significant challenge. Here we present a complete…

Solar and Stellar Astrophysics · Physics 2015-06-02 J. Jackiewicz , A. Serebryanskiy , S. Kholikov

Meridional circulation regulates the Sun's interior dynamics and magnetism. While it is well accepted that meridional flows are poleward at the Sun's surface, helioseismic observations have yet to provide a definitive answer for the depth…

We extend an existing Born approximation method for calculating the linear sensitivity of helioseismic travel times to flows from Cartesian to spherical geometry. This development is necessary for using the Born approximation for inferring…

Solar and Stellar Astrophysics · Physics 2016-06-15 Vincent G. A. Böning , Markus Roth , Wolfgang Zima , Aaron C. Birch , Laurent Gizon

To recover the flow information encoded in travel-time data of time-distance helioseismology, accurate forward modeling and a robust inversion of the travel times are required. We accomplish this using three-dimensional finite-frequency…

Astrophysics · Physics 2009-11-13 J. Jackiewicz , L. Gizon , A. C. Birch

The meridional flow in the Sun is an axisymmetric flow that is generally poleward directed at the surface, and is presumed to be of fundamental importance in the generation and transport of magnetic fields. Its true shape and strength,…

Solar and Stellar Astrophysics · Physics 2015-06-11 Thomas Hartlep , Junwei Zhao , Alexander G. Kosovichev , Nagi N. Mansour

The interpretation of helioseismic measurements, such as wave travel-time, is based on the computation of kernels that give the sensitivity of the measurements to localized changes in the solar interior. These are computed using the ray or…

Solar and Stellar Astrophysics · Physics 2018-09-12 Damien Fournier , Chris S. Hanson , Laurent Gizon , Helene Barucq

Here we use synthetic data to explore the performance of forward models and inverse methods for helioseismic holography. Specifically, this work presents the first comprehensive test of inverse modeling for flows using lateral-vantage…

Solar and Stellar Astrophysics · Physics 2018-08-15 K. DeGrave , D. C. Braun , A. C. Birch , A. D. Crouch , B. Javornik

We present and discuss results from time-distance helioseismic measurements of meridional circulation in the solar convection zone using 4 years of Doppler velocity observations by the Helioseismic and Magnetic Imager (HMI) onboard the…

Solar and Stellar Astrophysics · Physics 2015-11-11 S. P. Rajaguru , H. M. Antia

Large-scale plasma flows in the Sun's convection zone likely play a major role in solar dynamics on decadal timescales. In particular, quantifying meridional motions is a critical ingredient for understanding the solar cycle and the…

Solar and Stellar Astrophysics · Physics 2015-06-19 Shukur Kholikov , Alexander Serebryanskiy , Jason Jackiewicz

Mapping the large-scale subsurface plasma flow profile within the Sun has been attempted using various methods for several decades. One such flow in particular is the meridional circulation, for which numerous studies have been published.…

Solar and Stellar Astrophysics · Physics 2023-08-23 Aleczander Herczeg , Jason Jackiewicz

The consistency of time--distance inversions for horizontal components of the plasma flow on supergranular scales in the upper solar convection zone is checked by comparing the results derived using two k--\omega filtering procedures --…

Solar and Stellar Astrophysics · Physics 2015-06-16 Michal Svanda

The influence of the basic rotation on anisotropic and inhomogeneous turbulence is discussed in the context of differential rotation theory. An improved representation for the original turbulence leads to a $\Lam$-effect which complies with…

Astrophysics · Physics 2009-11-11 L. L. Kitchatinov , G. Rüdiger

Helioseismic waves observable at the solar surface can be used to probe the properties of the Sun's interior. By measuring helioseismic travel times between different location on the surface, flows and other interior properties can be…

Solar and Stellar Astrophysics · Physics 2021-03-24 Thomas Hartlep , Junwei Zhao

We present meridional flow measurements of the Sun using a novel helioseismic approach for analyzing SOHO/MDI data in order to push the current limits in radial depth. Analyzing three consecutive months of data during solar minimum, we find…

Astrophysics · Physics 2009-06-23 U. Mitra-Kraev , M. J. Thompson

Meridional flow in the solar interior plays an important role in redistributing angular momentum and transporting magnetic flux inside the Sun. Although it has long been recognized that the meridional flow is predominantly poleward at the…

Solar and Stellar Astrophysics · Physics 2015-06-16 Junwei Zhao , R. S. Bogart , A. G. Kosovichev , T. L. Duvall, , Thomas Hartlep

According to time-distance helioseismology, information about internal fluid motions is encoded in the travel times of solar waves. The inverse problem consists of inferring 3-D vector flows from a set of travel-time measurements. Here we…

Solar and Stellar Astrophysics · Physics 2015-05-27 M. Svanda , L. Gizon , S. M. Hanasoge , S. D. Ustyugov

We perform helioseismic holography to assess the noise in p-mode travel-time shifts which would form the basis of inferences of large-scale flows throughout the solar convection zone. We also derive the expected travel times from a…

Astrophysics · Physics 2009-11-13 D. C. Braun , A. C. Birch

Meridional circulation is a crucial component of the Sun's internal dynamics, but its inference in the deep interior is complicated by a systematic center-to-limb effect in helioseismic measurement techniques. Previously, an empirical…

Solar and Stellar Astrophysics · Physics 2017-11-15 Ruizhu Chen , Junwei Zhao
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