Related papers: Outstanding problems in local helioseismology
The solar atmosphere is extremely dynamic, and many important phenomena develop on small scales that are unresolved in observations with the Helioseismic and Magnetic Imager (HMI) instrument on the Solar Dynamics Observatory (SDO). For…
Helioseismology has provided very precise information about the solar internal sound speed and density throughout most of the solar interior. The results are generally quite close to the properties of standard solar models. Since the solar…
In recent years solar oscillations have been studied in great detail, both observationally and theoretically; so, perhaps, the Sun currently is the best understood pulsating star. The observational studies include long, almost uninterrupted…
In order to assess the ability of helioseismology to probe the subsurface structure and magnetic field of sunspots, we need to determine how helioseismic travel times depend on perturbations to sunspot models. Here we numerically simulate…
Convection is the mechanism by which energy is transported through the outermost 30% of the Sun. Solar turbulent convection is notoriously difficult to model across the entire convection zone where the density spans many orders of…
A new time--distance far-side imaging technique was recently developed by utilizing multiple multi-skip acoustic waves. The measurement procedure is applied to 11 years of Doppler observations from the Solar Dynamics Observatory /…
One of the main uncertainties associated with time-distance measurements is how to interpret observations made in regions of strong magnetic field as isolating the effects of the magnetic field from thermal or sound-speed perturbations has…
Context. Several upcoming helioseismology space missions are very limited in telemetry and will have to perform extensive data compression. This requires the development of new methods of data compression. Aims. We give an overview of the…
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…
Helioseismology has allowed us to study the structure of the Sun in unprecedented detail. One of the triumphs of the theory of stellar evolution was that helioseismic studies had shown that the structure of solar models is very similar to…
We perform helioseismic holography on realistic solar convection simulations and compare the observed travel-time perturbations with the expected travel times from the horizontal flows in the simulations computed from forward models under…
In the past decade, helioseismology has revolutionized our understanding of the interior structure of the Sun. In the next decade, asteroseismology will place this knowledge into context, by providing structural information for dozens of…
We review recent advances concerning helioseismology, solar models and solar neutrinos. Particularly we shall address the following points: i) helioseismic tests of recent SSMs; ii)the accuracy of the helioseismic determination of the sound…
We discuss current advances in forward and inverse modeling for local helioseismology. We report theoretical uniqueness results, in particular the Novikov-Agaltsov reconstruction algorithm, which is relevant to solving the non-linear…
Space plasmas are three-dimensional dynamic entities. Except under very special circumstances, their structure in space and their behavior in time are not related in any simple way. Therefore, single spacecraft in situ measurements cannot…
Solar oscillations frequencies show a distinct change with solar activity. The changes in frequencies can be used to study the time variation of solar structure. We discuss constraints on the changes in solar structure with time as obtained…
The solar cycle onset at mid-latitudes, the slow down of the sunspot drift toward the equator, the tail-like attachment and the overlap of successive cycles at the time of activity minimum are delicate issues in $\alpha\Omega$ dynamo wave…
Time-distance helioseismology has shown that f-mode travel times contain information about horizontal flows in the Sun. The purpose of this study is to provide a simple interpretation of these travel times. We study the interaction of…
The solar interior is filled with turbulent thermal convection, which plays a key role in the energy and momentum transport and the generation of the magnetic field. The turbulent flows in the solar interior cannot be optically detected due…
Being able to image active regions on the Sun's far side is useful for modeling the global-scale magnetic field around the Sun, and for predicting the arrival of major active regions that rotate around the limb onto the near side.…