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Related papers: A first look at the submillimeter Sun with ALMA

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Solar observations with the Atacama Large Millimeter/submillimeter Array (ALMA) provide us with direct measurements of the brightness temperature in the solar chromosphere. We study the temperature distributions obtained with ALMA Band 6…

Solar and Stellar Astrophysics · Physics 2019-02-13 Shahin Jafarzadeh , Sven Wedemeyer , Mikolaj Szydlarski , Bart De Pontieu , Reza Rezaei , Mats Carlsson

We present an overview of high resolution quiet Sun observations, from disk center to the limb, obtained with the Atacama Large mm and sub-mm Array (ALMA) at 3 mm. Seven quiet Sun regions were observed with resolution of up to 2.5" by 4.5".…

We present Atacama Large Millimeter/submillimeter Array (ALMA) observations of a quiet-Sun region at a wavelength of 3 mm, obtained during the first solar ALMA cycle on April 27, 2017, and compare them with available chromospheric…

Solar and Stellar Astrophysics · Physics 2019-06-05 Maria A. Loukitcheva , Stephen M. White , Sami K. Solanki

ALMA observations of the Sun at mm-$\lambda$ offer a unique opportunity to investigate the temperature structure of the solar chromosphere. In this article we expand our previous work on modeling the chromospheric temperature of the quiet…

Solar and Stellar Astrophysics · Physics 2020-08-19 C. E. Alissandrakis , A. Nindos , T. S. Bastian , S. Patsourakos

Solar observations at sub-mm, mm and cm wavelengths offer a straightforward diagnostic of physical conditions in the solar atmosphere because they yield measurement of brightness temperature which, for optically thick features, equals…

Solar and Stellar Astrophysics · Physics 2022-09-07 Costas Alissandrakis , Timothy Bastian , Roman Brajša

Various solar features can be seen on maps of the Sun in the mm and sub-mm wavelength range. The recently installed Atacama Large Millimeter/submillimeter Array (ALMA) is capable of observing the Sun in that wavelength range with an…

Solar and Stellar Astrophysics · Physics 2018-05-30 R. Brajša , D. Sudar , A. O. Benz , I. Skokić , M. Bárta , B. De Pontieu , S. Kim , A. Kobelski , M. Kuhar , M. Shimojo , S. Wedemeyer , S. White , P. Yagoubov , Y. Yan

We present an initial study of one of the first ALMA Band 3 observations of the Sun with the aim to characterise the diagnostic potential of brightness temperatures measured with ALMA on the Sun. The observation covers 48min at a cadence of…

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 Atacama Large Millimeter-submillimeter Array (ALMA) radio telescope has commenced science observations of the Sun starting in late 2016. Since the Sun is much larger than the field of view of individual ALMA dishes, the ALMA…

By direct measurements of the gas temperature, the Atacama Large Millimeter/sub-millimeter Array (ALMA) has yielded a new diagnostic tool to study the solar chromosphere. Here we present an overview of the brightness-temperature…

The Atacama Large Millimeter/submillimeter Array offers an unprecedented view of our Sun at sub-/millimeter wavelengths. The high spatial, temporal, and spectral resolution facilitates the measurement of gas temperatures and magnetic fields…

Solar and Stellar Astrophysics · Physics 2015-02-18 Sven Wedemeyer , Asbjorn Parmer

We studied chromospheric oscillations using Atacama Large millimeter and sub-millimeter Array (ALMA) time-series of interferometric observations of the quiet Sun obtained at 3 mm with a 2-s cadence and a spatial resolution of a few arcsec.…

Solar and Stellar Astrophysics · Physics 2020-02-12 S. Patsourakos , C. E. Alissandrakis , A. Nindos , T. S. Bastian

Using Atacama Large Millimeter/submillimeter Array (ALMA) observations of the quiet Sun at 1.26 and 3 mm, we study spatially resolved oscillations and transient brightenings, i.e. small, weak events of energy release. Both phenomena may…

Solar and Stellar Astrophysics · Physics 2021-08-18 A. Nindos , S. Patsourakos , C. E. Alissandrakis , T. S. Bastian

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

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 Atacama Large Millimeter-Submillimeter Array (ALMA) has opened a new window for studying the Sun via high-resolution high-sensitivity imaging at millimeter wavelengths. In this contribution I review the capabilities of the instrument…

Solar and Stellar Astrophysics · Physics 2019-02-13 Maria Loukitcheva

High-resolution observations of the solar chromosphere at millimeter wavelengths are now possible with the Atacama Large Millimeter Array (ALMA), promising to tackle many open problems in solar physics. Observations from other ground and…

Solar and Stellar Astrophysics · Physics 2018-12-12 João M. da Silva Santos , Jaime de la Cruz Rodríguez , Jorrit Leenaarts

Observations of the Sun at millimeter and submillimeter wavelengths offer a unique probe into the structure, dynamics, and heating of the chromosphere; the structure of sunspots; the formation and eruption of prominences and filaments; and…

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

We present sensitive high angular resolution ($\sim$ 0.1$''$ -- 0.3$''$) continuum ALMA (The Atacama Large Millimeter/Submillimeter Array) observations of the archetypal hot core located in Orion-KL. The observations were made in five…

Astrophysics of Galaxies · Physics 2017-10-04 M. T. Orozco-Aguilera , Luis A. Zapata , Tomoya Hirota , Sheng-Li Qin , Masqué Josep M.
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