Poster Open Access
Small-scale chromospheric bright features in a plage/enhanced network are identified in solar ALMA observations. The features present oscillations in brightness temperature, size and horizontal velocity. Interestingly, an anti-correlation between brightness temperature and size is also evident, suggesting that these features might be associated to fast-sausage MHD modes. A statistical analysis is carried out to quantify the oscillation periods of the three quantities and the phase angles between the perturbations in temperature and size. The values found are in agreement with periods of high frequency oscillations in other layers of the solar atmosphere.
Guevara Gómez, J. C., et al., "High-frequency oscillations in small chromospheric bright features observed with Atacama Large Millimetre/Submillimetre Array", Philosophical Transactions of the Royal Society of London Series A, vol. 379, no. 2190, 2021. doi:10.1098/rsta.2020.0184.
Jafarzadeh, S., et al., "An overall view of temperature oscillations in the solar chromosphere with ALMA", Philosophical Transactions of the Royal Society of London Series A, vol. 379, no. 2190, 2021. doi:10.1098/rsta.2020.0174.
Morton, R. J., et al., "Observations of Sausage Modes in Magnetic Pores", The Astrophysical Journal, vol. 729, no. 2, 2011. doi:10.1088/2041-8205/729/2/L18.
Guevara Gómez, Juan Camilo, & Wedemeyer, Sven. (2021). Dynamics of small-scale dark features observed by the Atacama Large Millimeter/Submillimeter Array (ALMA). Presented at the The 20.5th Cambridge Workshop on Cool Stars, Stellar Systems, and the Sun (CS20.5), virtually anywhere: Zenodo. http://doi.org/10.5281/zenodo.4567443