ALMA Memo 628 -- High-cadence observations of the Sun

Sven Wedemeyer; Mikolaj Szydlarski; M. Carmen Toribio; Tobia Carozzi; Daniel Jakobsson; Juan Camilo Guevara Gomez; Henrik Eklund; Vasco M. J. Henriques; Shahin Jafarzadeh; Jaime de la Cruz Rodriguez

arXiv · 2408.14265

ALMA Memo 628 -- High-cadence observations of the Sun

Sven Wedemeyer·Mikolaj Szydlarski·M. Carmen Toribio·Tobia Carozzi·Daniel Jakobsson·Juan Camilo Guevara Gomez·Henrik Eklund·Vasco M. J. Henriques·Shahin Jafarzadeh·Jaime de la Cruz Rodriguez

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Abstract

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 thermometer for atmospheric gas, aiding in understanding the solar atmosphere's structure, dynamics, and energy balance. Given the Sun's complex emission patterns and rapid evolution, high-cadence imaging is essential for solar observations. Snapshot imaging is required, though it limits available visibility data, making full exploitation of ALMA's capabilities non-trivial. Challenges in processing solar ALMA data highlight the need for revising and enhancing the solar observing mode. The ALMA development study High-Cadence Imaging of the Sun demonstrated the potential benefits of high cadence observations through a forward modelling approach. The resulting report provides initial recommendations for improved post-processing solar ALMA data and explores increasing the observing cadence to sub-second intervals to improve image reliability.

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Sven Wedemeyer, Mikolaj Szydlarski, M. Carmen Toribio, Tobia Carozzi, Daniel Jakobsson, Juan Camilo Guevara Gomez, Henrik Eklund, Vasco M. J. Henriques, Shahin Jafarzadeh, Jaime de la Cruz Rodriguez. 2024-08-26. ALMA Memo 628 -- High-cadence observations of the Sun. https://arxiv.org/abs/2408.14265

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