Signatures of Thermal and Radiative Oscillations in Solar Coronal Loops‎: ‎A Study of AR 11092

In this study, we investigated intensity and temperature oscillations using extracted slices of three loops taken from data of four extreme ultraviolet (EUV) channels recorded by the Atmospheric Imaging Assembly (AIA) onboard the Solar Dynamic Observatory (SDO). We applied loops data of active region (AR 11092) from 13:30:00 UT till 18:00:00 UT on August 1, 2010. These slices have lengths of 33, 29, and 18 Mm analyzed at the wavelengths of 131˚A, 171˚A, 193˚A, and 211˚A. Exponential fits to intensity profiles enabled estimation of oscillation parameters: period, damping time, phase speed, and damping quality factor. Mean periods for slices S1, S2, and S3 were 26.13, 26.15, and 28.19 minutes, respectively. Cross-correlation analysis across wavelengths showed the highest coefficients between 131˚A, and 171˚A for all slices, with strong correlations across all wavelength pairs. Temperature diagnostics using the CHIANTI code yielded loop temperatures between 5.6 and 7.2 MK, with closely matched values among loops. From mean temperature, uncertainty, and dominant period, phase speed (Vph) and sound speed (Cs) were derived; for S1: 81.48km/s, and 367.50km/s, for S2: 80.09km/s, and 368.96km/s, for S3: 103.70km/s, and 374.77km/s. In all cases, Vph < Cs, consistent with standing slow-mode waves. Phase difference analysis between intensity and temperature oscillations showed positive values, with intensity peaks leading temperature peaks by a mean phase difference of ( 1/4 ±0.01)π. These results confirmed the presence of standing slow-mode waves in these three loops.