English
Related papers

Related papers: The Sun at millimeter wavelengths I. Introduction …

200 papers

Polar brightening of the Sun at radio frequencies has been studied for almost fifty years and yet a disagreement persists between solar atmospheric models and observations. Some observations reported brightening values much smaller than the…

The Atacama Large Millimeter/sub-millimeter Array (ALMA) has provided us with an excellent diagnostic tool for studies of the dynamics of the Solar chromosphere, albeit through a single receiver band at one time presently. Each ALMA band…

Solar and Stellar Astrophysics · Physics 2022-09-14 Juan Camilo Guevara Gómez , Shahin Jafarzadeh , Sven Wedemeyer , Mikolaj Szydlarski

Quiescent filaments appear as absorption features on the solar disk when observed in chromospheric lines and at continuum wavelengths in the millimeter (mm) range. Active region (AR) filaments are their small-scale, low-altitude analogues,…

Solar and Stellar Astrophysics · Physics 2022-04-29 J. M. da Silva Santos , S. M. White , K. Reardon , G. Cauzzi , S. Gunár , P. Heinzel , J. Leenaarts

The Atacama Large Millimeter/submillimeter Array (ALMA) offers new diagnostic possibilities that complement other commonly used diagnostics for the study of our Sun. In particular, ALMA's ability to serve as an essentially linear…

The Atacama Large Millimeter-submillimeter Array (ALMA) is a general purpose telescope that performs a broad program of astrophysical observations. Beginning in late-2016, solar observations with ALMA became available, thereby opening a new…

Solar and Stellar Astrophysics · Physics 2024-02-14 Masumi Shimojo , Timothy S. Bastian , Seiji Kameno , Antonio S. Hales

The Atacama Large Millimeter/submillimeter Array (ALMA) offers new diagnostic capabilities for studying the Sun, providing complementary insights through high spatial and temporal resolution at millimeter wavelengths. ALMA acts as a linear…

The Atacama Large Millimeter/submillimeter Array (ALMA) allows for solar observations in the wavelength range of 0.3$-$10 mm, giving us a new view of the chromosphere. The measured brightness temperature at various frequencies can be fitted…

Solar and Stellar Astrophysics · Physics 2024-03-01 F. Matković , R. Brajša , M. Kuhar , A. O. Benz , H. -G. Ludwig , C. L. Selhorst , I. Skokić , D. Sudar , A. Hanslmeier

The (sub)millimeter radiation of solar flares is poorly understood. Without spatial resolution, it cannot be compared easily to flare emissions in other wavelengths. The Atacama Large Millimeter-submillimeter Array (ALMA) offers sufficient…

Solar and Stellar Astrophysics · Physics 2023-02-01 I. Skokić , A. O. Benz , R. Brajša , D. Sudar , F. Matković , M. Bárta

Waves and oscillations are important solar phenomena, not only because they can propagate and dissipate energy in the chromosphere, but also because they carry information about the structure of the atmosphere in which they propagate. The…

Solar and Stellar Astrophysics · Physics 2022-01-26 Yi Chai , Dale E. Gary , Kevin P. Reardon , Vasyl Yurchyshyn

Aims. The main aim of the present analysis is to decipher (i) the small-scale bright features in solar images of the quiet Sun and active regions obtained with the Atacama Large Millimeter/submillimeter Array (ALMA) and (ii) the ALMA…

Solar and Stellar Astrophysics · Physics 2021-07-07 R. Brajsa , I. Skokic , D. Sudar , A. O. Benz , S. Krucker , H. -G. Ludwig , S. H. Saar , C. L. Selhorst

Observations at millimetre wavelengths provide a valuable tool to study the small scale dynamics in the solar chromosphere. We evaluate the physical conditions of the atmosphere in the presence of a propagating shock wave and link that to…

Solar and Stellar Astrophysics · Physics 2021-01-20 Henrik Eklund , Sven Wedemeyer , Ben Snow , David B. Jess , Shahin Jafarzadeh , Samuel D. T. Grant , Mats Carlsson , Mikolaj Szydlarski

We report observations of solar spicules at millimeter wavelengths (mm-$\lambda$) using the Atacama Large Millimeter/submillimeter Array (ALMA). These are supplemented by observations in optical (O), ultraviolet (UV) and extreme ultraviolet…

Solar and Stellar Astrophysics · Physics 2025-04-09 T. S. Bastian , C. Alissandrakis , A. Nindos , M. Shimojo , S. M. White

New instruments sensitive to chromospheric radiation at X-ray, UV, Visible, IR, and sub-mm wavelengths have become available that significantly enhance our ability to understand the bi-directional flow of energy through the chromosphere. We…

Solar and Stellar Astrophysics · Physics 2022-07-27 Adam R. Kobelski , Lucas A. Tarr , Sarah A. Jaeggli , Nicholas Luber , Harry P. Warren , Sabrina L. Savage

Science Verification (SV) data of solar observations with Atacama Large Millimeter-submillimeter Array (ALMA) telescope were released to the scientific community. Understanding the centre to limb brightness function is necessary to compare…

Solar and Stellar Astrophysics · Physics 2019-09-20 Davor Sudar , Roman Brajša , Ivica Skokić , Arnold O. Benz

We present four daytime thermal images of Europa taken with the Atacama Large Millimeter Array. Together, these images comprise the first spatially resolved thermal dataset with complete coverage of Europa's surface. The resulting…

Earth and Planetary Astrophysics · Physics 2018-10-31 Samantha K. Trumbo , Michael E. Brown , Bryan J. Butler

We present the first observations of the Sun with the Allen Telescope Array (ATA). We used up to six frequencies, from 1.43 to 6 GHz, and baselines from 6 to 300 m. To our knowledge, these are the first simultaneous multifrequency full-Sun…

Solar and Stellar Astrophysics · Physics 2016-11-25 Pascal Saint-Hilaire , Gordon J. Hurford , Garrett Keating , Geoffrey C. Bower , Colby Gutierrez-Kraybill

We measured the center-to-limb variation of the brightness temperature, $T_b$, from ALMA full-disk images at two frequencies and inverted the solution of the transfer equation to obtain the electron temperature, $T_e$ as a function of…

Solar and Stellar Astrophysics · Physics 2017-09-13 C. E. Alissandrakis , S. Patsourakos , A. Nindos , T. S. Bastian

The absolute brightness temperature of the Sun at millimeter wavelengths is an important diagnostic of the solar chromosphere. Because the Sun is so bright, measurement of this property usually involves the operation of telescopes under…

Solar and Stellar Astrophysics · Physics 2017-01-02 Kazumasa Iwai , Masumi Shimojo , Shinichiro Asayama , Tetsuhiro Minamidani , Stephen White , Timothy Bastian , Masao Saito

We use state-of-the-art, three-dimensional non-local thermodynamic equilibrium (non-LTE) radiative magnetohydrodynamic simulations of the quiet solar atmosphere to carry out detailed tests of chromospheric magnetic field diagnostics from…

Solar and Stellar Astrophysics · Physics 2017-04-26 Maria Loukitcheva , Stephen M. White , Sami K. Solanki , Gregory D. Fleishman , Mats Carlsson