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Related papers: The Sun at millimeter wavelengths IV. Magnetohydro…

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We report detection of oscillations in brightness temperature, size, and horizontal velocity of three small bright features in the chromosphere of a plage/enhanced-network region. The observations, which were taken with high temporal…

Solar observations with the Atacama Large Millimeter/sub-millimeter Array (ALMA) facilitate studying the atmosphere of the Sun at chromospheric heights at high spatial and temporal resolution at millimeter wavelengths. ALMA intensity data…

Solar and Stellar Astrophysics · Physics 2020-12-23 Henrik Eklund , Sven Wedemeyer , Mikolaj Szydlarski , Shahin Jafarzadeh , Juan Camilo Guevara Gómez

Magnetohydrodynamic (MHD) waves, playing a crucial role in transporting energy through the solar atmosphere, manifest in various chromospheric structures. Here, we investigated MHD waves in a long-lasting dark fibril using…

Solar and Stellar Astrophysics · Physics 2024-12-25 Maryam Saberi , Shahin Jafarzadeh , Sven Wedemeyer , Ricardo Gafeira , Mikolaj Szydlarski , David Jess , Marco Stangalini

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

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 study the properties of slow magneto-acoustic waves that are naturally excited due to turbulent convection and investigate their role in the energy balance of a plage region using three dimensional (3D) radiation-MHD simulations. We…

Solar and Stellar Astrophysics · Physics 2021-08-11 Nitin Yadav , Robert H. Cameron , Sami K. Solanki

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…

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

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 have implemented control and data-taking software that makes it possible to scan the beams of individual ALMA antennas to perform quite complex patterns while recording the signals at high rates. We conducted test observations of the Sun…

Instrumentation and Methods for Astrophysics · Physics 2015-02-24 Neil Phillips , Richard Hills , Tim Bastian , Hugh Hudson , Ralph Marson , Sven Wedemeyer

We present the first full-disk solar images obtained with the Atacama Large Millimeter/submillimeter Array (ALMA) in Band 7 (0.86 mm; 347 GHz). In spite of the low spatial resolution (21"), several interesting results were obtained. During…

Solar and Stellar Astrophysics · Physics 2022-05-25 C. E. Alissandrakis , T. S. Bastian , A. Nindos

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

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

The presence of magneto-acoustic waves in magnetic structures in the solar atmosphere is well-documented. Applying the technique of solar magneto-seismology (SMS) allows us to infer the background properties of these structures. Here, we…

Solar and Stellar Astrophysics · Physics 2016-01-27 N. Freij , I. Dorotovic , R. J. Morton , M. S. Ruderman , V. Karlovsky , R. Erdekyi

We present high-cadence observations and simulations of the solar photosphere, obtained using the Rapid Oscillations in the Solar Atmosphere imaging system and the MuRAM magneto-hydrodynamic code, respectively. Each dataset demonstrates a…

Solar and Stellar Astrophysics · Physics 2015-06-03 D. B. Jess , S. Shelyag , M. Mathioudakis , P. H. Keys , D. J. Christian , F. P. Keenan

Interferometric observations of the Sun with ALMA provide valuable diagnostic tools for studying the small-scale dynamics of the solar atmosphere. Estimations of the observability of the small-scale dynamics as a function of spatial…

Solar and Stellar Astrophysics · Physics 2021-12-08 Henrik Eklund , Sven Wedemeyer , Mikołaj Szydlarski , Shahin Jafarzadeh

We report on the spatial distribution of magnetogram oscillatory power and phase angles between velocity and magnetogram signals as observed with the Michelson Doppler Imager. The dataset is 151.25 arcsec times 151.25 arcsec containing…

Astrophysics · Physics 2009-10-31 A. A. Norton , R. K. Ulrich , R. I. Bush , T. D. Tarbell

The very nature of the solar chromosphere, its structuring and dynamics, remains far from being properly understood, in spite of intensive research. Here we point out the potential of chromospheric observations at millimeter wavelengths to…

Astrophysics · Physics 2009-06-23 M. A. Loukitcheva , S. K. Solanki , S. White

The continuum intensity at wavelengths around 1 mm provides an excellent way to probe the solar chromosphere. Future high-resolution millimetre arrays, such as the Atacama Large Millimeter Array (ALMA), will thus produce valuable input for…

Astrophysics · Physics 2009-11-13 S. Wedemeyer-Boehm , H. -G. Ludwig , M. Steffen , J. Leenaarts , B. Freytag

Slow magnetoacoustic waves (SMAWs) have been considered in the past as a possible candidate for chromospheric heating. This study analyzes 20 active regions observed between 2012 and 2016 to examine the amplitude and energy flux variation…

Solar and Stellar Astrophysics · Physics 2025-04-22 Y. Sanjay , S. Krishna Prasad , P. S. Rawat
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