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An updated version of the dust radiation transfer code Sunrise, including models for star-forming regions and a self-consistent calculation of the spatially dependent dust and PAH emission, is presented. Given a hydrodynamic simulation of a…

Cosmology and Nongalactic Astrophysics · Physics 2016-09-08 Patrik Jonsson , Brent Groves , T. J. Cox

In a previous work, we reported on the discovery of supersonic magnetic upflows on granular cells in data from the {\sc Sunrise}/IMaX instrument. In the present work we investigate the physical origin of these events employing data of the…

Solar and Stellar Astrophysics · Physics 2015-06-15 J. M. Borrero , V. Martinez Pillet , W. Schmidt , C. Quintero Noda , J. A. Bonet , J. C. del Toro Iniesta , L. R. Bellot Rubio

Using the IMaX instrument on-board the Sunrise stratospheric balloon-telescope we have detected extremely shifted polarization signals around the Fe I 5250.217 {\AA} spectral line within granules in the solar photosphere. We interpret the…

The irradiance of the Sun is modulated on all time scales. Small-scale solar magnetic elements composed of quiet-Sun network and active region plages contribute to this modulation on solar cycle time scales. The evaluation of their contrast…

Solar and Stellar Astrophysics · Physics 2021-09-02 Fatima Kahil

Context. The Spectrometer/Telescope for Imaging X-rays (STIX) is one of 6 remote sensing instruments on-board Solar Orbiter. It provides hard X-ray imaging spectroscopy of solar flares by sampling the Fourier transform of the incoming flux.…

The effects of acoustic wave absorption, mode conversion and transmission by a sunspot on the helioseismic inferences are widely discussed, but yet accounting for them has proved difficult for lack of a consistent framework within…

Solar and Stellar Astrophysics · Physics 2012-06-26 S. P. Rajaguru

Local helioseismology has opened new frontiers in our quest for understanding of the internal dynamics and dynamo on the Sun. Local helioseismology reconstructs subsurface structures and flows by extracting coherent signals of acoustic…

Solar and Stellar Astrophysics · Physics 2016-07-20 Alexander G. Kosovichev , Junwei Zhao

Using high-resolution ring analysis (HRRA) we deduce subsurface flows within magnetic active regions and within quiet sun. With this procedure we are capable of measuring flows with a horizontal spatial resolution of 2 degrees in…

Solar and Stellar Astrophysics · Physics 2011-02-11 Bradley W. Hindman , Deborah A. Haber , Juri Toomre

Observations of the solar photosphere show spatially-compact large-amplitude Doppler velocity events with short lifetimes. In data from the Imaging Magnetograph eXperiment (IMaX) on the first flight of the Sunrise balloon in 2009, events…

Solar and Stellar Astrophysics · Physics 2019-02-13 R. Lee McClure , Mark P. Rast , Valentin MartınezPillet

In passive imaging, one attempts to reconstruct some coefficients in a wave equation from correlations of observed randomly excited solutions to this wave equation. Many methods proposed for this class of inverse problem so far are only…

Numerical Analysis · Mathematics 2024-03-12 Björn Müller , Thorsten Hohage , Damien Fournier , Laurent Gizon

Optical flow is inherently a 2D search problem, and thus the computational complexity grows quadratically with respect to the search window, making large displacements matching infeasible for high-resolution images. In this paper, we take…

Computer Vision and Pattern Recognition · Computer Science 2021-08-31 Haofei Xu , Jiaolong Yang , Jianfei Cai , Juyong Zhang , Xin Tong

In this dissertation, several components of large-scale solar flows are studied observationally: solar equatorial Rossby waves (waves of radial vorticity), large-scale convection, and surface flows around active regions. Maps of horizontal…

Solar and Stellar Astrophysics · Physics 2023-01-25 Bastian Proxauf

Solar active regions (ARs) are thought to be formed by magnetic fields from the convection zone. Our flux emergence simulations revealed that a strong horizontal divergent flow (HDF) of unmagnetized plasma appears at the photosphere before…

Solar and Stellar Astrophysics · Physics 2015-06-22 Shin Toriumi , Keiji Hayashi , Takaaki Yokoyama

This paper describes the wave-front correction system developed for the Sunrise balloon telescope, and provides information about its in-flight performance. For the correction of low-order aberrations, a Correlating Wave-Front Sensor (CWS)…

Spectropolarimetric observations used to infer the solar magnetic fields are obtained with a limited spatial resolution. The effects of this limited resolution on the inference of the open flux over the observed region have not been…

Solar and Stellar Astrophysics · Physics 2024-02-06 Ivan Milic , Rebecca Centeno , Xudong Sun , Matthias Rempel , Jaime de la Cruz Rodriguez

Current post-processing techniques for the correction of atmospheric seeing in solar observations -- such as Speckle interferometry and Phase Diversity methods -- have limitations when it comes to their reconstructive capabilities of solar…

Solar and Stellar Astrophysics · Physics 2020-12-09 John A. Armstrong , Lyndsay Fletcher

Intermittent magnetohydrodynamical turbulence is most likely at work in the magnetized solar atmosphere. As a result, an array of scaling and multi-scaling image-processing techniques can be used to measure the expected self-organization of…

Astrophysics · Physics 2007-05-23 Manolis K. Georgoulis

Solar limb observations sometimes reveal the presence of a satellite lobe in the blue wing of the Stokes I profile from pixels belonging to granules. The presence of this satellite lobe has been associated in the past to strong line of…

Solar and Stellar Astrophysics · Physics 2016-01-18 C. Quintero Noda , T. Shimizu , Y. Suematsu

Recently, we have developed a method useful for mapping large-scale horizontal velocity fields in the solar photosphere. The method was developed, tuned and calibrated using the synthetic data. Now, we applied the method to the series of…

Astrophysics · Physics 2009-11-13 Michal Svanda , Mirek Klvana , Michal Sobotka , Vaclav Bumba

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