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tokens: traveling intensity perturbation of a hot, 8–10 MK, coronal loop, in a C7.4 class flare, with SDO /AIA. The intensity variation was seen to bounce approximately four times between the loop’s footpoints, before fading, i.e., exhibiting a “zigzag” pattern in a time–distance plot made along the apparent direction of the magnetic field. The oscillation period and decay time were about 630 s and 440 s, respectively. The apparent phase speed was about 460–510 km s −1 which matched the sound speed in the loop. The authors suggested calling this phenomenon a reflecting longitudinal wave, while Reale ( 2016 ) introduced the term “sloshing” oscillations for this phenomenon. A similar, bouncing back and forth between the footpoints, EUV intensity perturbation was detected in another C-class flare by Kumar et al. ( 2015 ). The period of the oscillation and decay time were about 409 s and 1121 s, respectively. The characteristic phase speed of the wave is about 560 km s −1 , which was roughly consistent with the sound speed at the temperature of about 10–16 MK. Wang et al. ( 2015 ) observed a clear sloshing pattern in the 131 Å intensity oscillation with SDO /AIA. The oscillation period, decay time, and the apparent phase speed were estimated as about 12 minutes, 9 minutes, and 500 km s −1 , respectively. Mandal et al. ( 2016 ) reported a simultaneous observation of a propagating and reflecting intensity disturbance in a hot coronal loop observed in EUV and X-rays with SDO /AIA and Hinode /XRT, respectively. In addition, three other cases of intensity pulses sloshing between footpoints were analyzed. In all considered cases the projected traveling speed was found to be lower than the local sound speed, consistent with the slow wave interpretation. Pant et al. ( 2017 ) observed antiphase oscillations of the 171 and 193 Å intensity oscillations at two ends of a nonflaring fan loop system observed with SDO /AIA. The oscillation period was estimated to be 27 minutes, the damping time of 45 minutes, and the apparent phase speed of about 75 km s −1 . The time–distance map made along the loop showed a sloshing (i.e., “zigzagging”) motion pattern. We need to point out that sloshing oscillations are different from other manifestations of slow waves in the corona, propagating (not reflecting) slow waves that are detected in polar plumes and near footpoints of long loops (see, e.g., de Moortel 2009 ). Numerical modeling of slow oscillations in a coronal loop reproduced main properties of standing (SUMER) and sloshing oscillations, i.e., the observed oscillation period, P slow ≈ 2 L / C s , where L is the loop length and C s is the sound speed; and associated the rapid damping of the oscillation with the effect of thermal conduction (Ofman Wang 2002 ). Nakariakov Zimovets ( 2011 ) demonstrated that a similar periodicity could occur in arcades. The preferential excitation of lower, i.e., the fundamental and second parallel harmonics by an impulsive source, was found