Description
Ultraviolet (UV) or extreme ultraviolet (EUV) passbands, despite being relatively narrow, typically include significant contribution from multiple ions, thus leading to mixed emission from widely despairing temperature formation regimes. This is particularly limiting for diagnostic purposes of the plasma temperature, where extreme cool/hot values in the solar/stellar coronae can be attributed to specific physical mechanisms such as magnetic reconnection or thermal instability. For solar observations, the ambiguity is particularly large when observing off-limb, where line-of-sight superposition is maximal and the diffuse, hot emission becomes comparable in intensity to that of clumpy, cool structures such as spicules, coronal rain and prominences. Recent work [1] has shown that the Response Fitting (RFit) method is particularly good and highly efficient in disambiguating the emission in the AIA 304 Å passband. This method is based on knowledge of the temperature response functions of the given passbands. In this work we further extend this method to other SDO/AIA channels and the IRIS/SJI 1330 and 1400 channels. We show that this method is generally very effective at isolating the cool, warm or hot emission, in both quiescent and flaring events.
[1] Antolin, P., Auchère, F., Winch, E., Soubrié, E., Oliver, R., Sol. Phys. 299, 94 (2024)
