4298 20191113154923.0 POSTER-2019-0099 Podladchikova, T Multiple EUV wave reflection from a coronal hole 2019 2019-11-18 EUV waves are large-scale propagating disturbances in the solar corona initiated by coronal mass ejections. We investigate the multiple EUV wave reflections at a coronal hole boundary, as observed by SDO/AIA 195 Å on 1 April 2017. The EUV wave originates from Active Region (AR) 12645 close to the disk center and propagates toward the south polar coronal hole with an average velocity of 346 km/s. The interaction of the EUV wave with the coronal hole, which represents a region of high Alfven speed, is observed as a splitting into two wave components: one continues propagation inside the coronal hole with an increased velocity of 1300 km/s (transmitted wave), while the other one moves back toward the AR, also with an increased velocity of 609 km/s (reflected wave). The reflected EUV wave is subsequently reflected again from the AR and propagates toward the coronal hole, where it is reflected for the second time at coronal hole boundary and propagates again toward the AR with a velocity of 406 km/s. These events are observed over an interval of 40 minutes. The high cadence SDO imagery allows us to study in detail the kinematics of the direct and multiple times reflected EUV wave. In addition, its multi-wavelength EUV imagery allows us to derive the plasma properties of the corona and the EUV wave pulse via Differential Emission Measure analysis STCE WP ROB A.3/ STCE WP ROB A.3/ STCE WP ROB A.3 STCE space weather, CME initiation, EUV waves Veronig, A Podladchikova, 0 Dissauer, K Vršnak, B Saqri, J Piantschitsch, I Temmer, M 16th European Space Weather Week, Liege, Belgium elena.podladchikova@observatoire.be http://www.stce.be/esww2019/program/session_details.php?nr=5 4663956 http://publi2-as.oma.be/record/4298/files/Multiple_reflection_from_coronal_hole_ESWW_2019.pdf 32458 http://publi2-as.oma.be/record/4298/files/Multiple_reflection_from_coronal_hole_ESWW_2019.jpg?subformat=icon-180 icon-180 35180 http://publi2-as.oma.be/record/4298/files/Multiple_reflection_from_coronal_hole_ESWW_2019.gif?subformat=icon icon CPOSTER