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Multidisciplinary Sciences
Ryohko Ishikawa, Javier Trujillo Bueno, Tanausu del Pino Aleman, Takenori J. Okamoto, David E. McKenzie, Frederic Auchere, Ryouhei Kano, Donguk Song, Masaki Yoshida, Laurel A. Rachmeler, Ken Kobayashi, Hirohisa Hara, Masahito Kubo, Noriyuki Narukage, Taro Sakao, Toshifumi Shimizu, Yoshinori Suematsu, Christian Bethge, Bart De Pontieu, Alberto Sainz Dalda, Genevieve D. Vigil, Amy Winebarger, Ernest Alsina Ballester, Luca Belluzzi, Jiri Stepan, Andres Asensio Ramos, Mats Carlsson, Jorrit Leenaarts
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Astronomy & Astrophysics
Yang Liu, Ana Belen Grinon-Marin, Jon T. Hoeksema, Aimee A. Norton, Xudong Sun
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Astronomy & Astrophysics
Andrei Plotnikov, Alexander Kutsenko, Shangbin Yang, Haiquing Xu, Xianyong Bai, Hongqi Zhang, Kirill Kuzanyan
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Astronomy & Astrophysics
F. Kahil, A. Gandorfer, J. Hirzberger, D. Calchetti, J. Sinjan, G. Valori, S. K. Solanki, M. Van Noort, K. Albert, N. Albelo Jorge, A. Alvarez-Herrero, T. Appourchaux, L. R. Bellot Rubio, J. Blanco Rodriguez, A. Feller, B. Fiethe, D. Germerott, L. Gizon, L. Guerrero, P. Gutierrez-Marques, M. Kolleck, A. Korpi-Lagg, H. Michalik, A. Moreno Vacas, D. Orozco Suarez, I. Perez-Grande, E. Sanchis Kilders, J. Schou, U. Schuehle, J. Staub, H. Strecker, J. C. del Toro Iniesta, R. Volkmer, J. Woch
Summary: In this study, wavefront sensing is used to characterize the image quality of the High Resolution Telescope (HRT) of the Polarimetric and Helioseismic Imager (SO/PHI) during the Solar Orbiter (SO) mission. The wavefront error of HRT is determined using a pair of focused-defocused images and the point spread function (PSF) is derived through phase diversity analysis. The results show that the wavefront error of HRT is influenced by the distance of SO to the Sun, with the thermo-optical effect of the Heat Rejection Entrance Window (HREW) becoming noticeable at distances <0.5 au. An interpolation scheme is developed to account for the thermal variation of HREW with distance. Additionally, an aberration correction method is introduced to reduce noise caused by image deconvolution while removing aberrations caused by HREW.
ASTRONOMY & ASTROPHYSICS
(2023)
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Astronomy & Astrophysics
Daiki Yamasaki, Shin'ichi Nagata, Kiyoshi Ichimoto
Summary: The Tandem Etalon Magnetograph (TEM) is an instrument that achieves high polarimetric sensitivity and addresses spatial variation in the response matrix through calibration.
PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN
(2022)
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Astronomy & Astrophysics
I. Tahtinen, I. I. Virtanen, A. A. Pevtsov, K. Mursula
Summary: By studying the relationship between photospheric magnetic fields and ultraviolet radiation, we found that the percentage of bright pixels can explain the variability of 1600 angstrom emission. We developed a model to predict the size of the photospheric magnetic field and found a close correspondence between the magnetic field and bright and dark clusters.
ASTRONOMY & ASTROPHYSICS
(2022)
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Astronomy & Astrophysics
I. O. I. Virtanen, A. A. Pevtsov, L. Bertello, K. Mursula
Summary: This study reconstructs synoptic maps of the photospheric magnetic field from observations of chromospheric plages and the magnetic polarity of sunspots, and uses these maps to investigate the long-term evolution of the Sun's global magnetic fields. The results show a realistic cyclic behavior of the reconstructed active regions, although the polar field strengths in certain cycles may not accurately reflect the evolution of the sunspot number. The modeled coronal structure shows fair agreement with eclipse drawings.
ASTRONOMY & ASTROPHYSICS
(2022)
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Astronomy & Astrophysics
X. Zhu, T. Wiegelmann
Summary: The aim of this study is to develop a fast and consistent extrapolation method for modeling multiple layers of the solar atmosphere. The new approach combines the magnetohydrostatic extrapolation with the nonlinear force-free field extrapolation, resulting in accurate and efficient reconstruction of the magnetic fields.
ASTRONOMY & ASTROPHYSICS
(2022)
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Astronomy & Astrophysics
I. O. I. Virtanen, A. A. Pevtsov, I. I. Virtanen, K. Mursula
Summary: Researchers constructed additional active regions and applied them to the far-side of the Sun in an SFT simulation to assess the possible effects and the magnitude of error that the missing far-side flux causes. The results showed that adding active regions with short lifetimes to the far-side of the Sun results in significantly stronger polar fields in minimum times and slightly delayed polarity reversals.
ASTRONOMY & ASTROPHYSICS
(2021)
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Astronomy & Astrophysics
Xianyong Bai, Hui Liu, Yuanyong Deng, Jie Jiang, Jingjing Guo, Yi Bi, Tao Feng, Zhenyu Jin, Wenda Cao, Jiangtao Su, Kaifan Ji
Summary: This study proposes a new method to estimate the magnetic field components from photospheric continuum images using deep convolutional neural networks. Experimental results show that the method can successfully estimate the magnetic field in different regions of the Sun, providing quick and accurate magnetic field information.
ASTRONOMY & ASTROPHYSICS
(2021)
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Multidisciplinary Sciences
Elizabeth Gibney
Summary: This mission aims to enhance forecasts of damaging space weather.
News Item
Multidisciplinary Sciences
Anil Oza
Summary: The US National Science Foundation plans to utilize the historic site for biology and computer science education.
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Astronomy & Astrophysics
Gherardo Valori, Philipp Loeschl, David Stansby, Etienne Pariat, Johann Hirzberger, Feng Chen
Summary: The stereoscopic disambiguation method (SDM) shows a high accuracy in removing the 180 degrees ambiguity in solar vector magnetic field orientations, reaching nearly 100% in moderately-to-well resolved fields. However, in certain configurations where spacecraft position is within a few degrees of co-alignment or quadrature, accuracy may vary. Additionally, the accuracy of SDM is found to be sensitive to the spatial resolution of the Solar Orbiter's elliptic orbit and the observed field's spatial scale.
Review
Engineering, Multidisciplinary
XiaoShuai ZHU, Thomas NEUKIRCH, Thomas WIEGELMANN
Summary: Understanding the structure and evolution of magnetic fields and plasma in different layers of the Sun is crucial. While force-free magnetic fields are widely used for modeling the solar corona, a magnetohydrostatic equilibrium is more appropriate for the lower atmosphere due to the high plasma beta. This paper reviews analytical and numerical methods based on the magnetohydrostatic assumption for calculating magnetic fields and plasma in the solar atmosphere from measured magnetograms.
SCIENCE CHINA-TECHNOLOGICAL SCIENCES
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J. Sinjan, D. Calchetti, J. Hirzberger, F. Kahil, G. Valori, S. K. Solanki, K. Albert, N. Albelo Jorge, A. Alvarez-Herrero, T. Appourchaux, L. R. Bellot Rubio, J. Blanco Rodriguez, A. Feller, A. Gandorfer, D. Germerott, L. Gizon, J. M. Gomez Cama, L. Guerrero, P. Gutierrez-Marques, M. Kolleck, A. Korpi-Lagg, H. Michalik, A. Moreno Vacas, D. Orozco Suarez, I. Perez-Grande, E. Sanchis Kilders, M. Balaguer Jimenez, J. Schou, U. Schuehle, J. Staub, H. Strecker, J. C. del Toro Iniesta, R. Volkmer, J. Woch
Summary: This study compares the magnetic field maps obtained by the Solar Orbiter and Solar Dynamics Observatory satellites and discusses possible differences between them. The results show that the line-of-sight magnetograms obtained by the two instruments are remarkably similar, but the vector magnetic field inferred by the Solar Orbiter is stronger, which may be due to data noise.
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Steven Tomczyk, Jie Zhang, Timothy Bastian, John W. Leibacher
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ASTROPHYSICAL JOURNAL LETTERS
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ASTROPHYSICAL JOURNAL LETTERS
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