Why “solar tsunamis” rarely leave their imprints in the chromosphere. (arXiv:2304.14859v1 [astro-ph.SR])
<a href="http://arxiv.org/find/astro-ph/1/au:+Zheng_R/0/1/0/all/0/1">Ruisheng Zheng</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Liu_Y/0/1/0/all/0/1">Yihan Liu</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Liu_W/0/1/0/all/0/1">Wenlong Liu</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Wang_B/0/1/0/all/0/1">Bing Wang</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Hou_Z/0/1/0/all/0/1">Zhenyong Hou</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Feng_S/0/1/0/all/0/1">Shiwei Feng</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Kong_X/0/1/0/all/0/1">Xiangliang Kong</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Huang_Z/0/1/0/all/0/1">Zhenghua Huang</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Song_H/0/1/0/all/0/1">Hongqiang Song</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Tian_H/0/1/0/all/0/1">Hui Tian</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Chen_P/0/1/0/all/0/1">Pengfei Chen</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Erdelyi_R/0/1/0/all/0/1">Robertus Erd&#xe9;lyi</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Chen_Y/0/1/0/all/0/1">Yao Chen</a>

Solar coronal waves frequently appear as bright disturbances that propagate
globally from the eruption center in the solar atmosphere, just like the
tsunamis in the ocean on Earth. Theoretically, coronal waves can sweep over the
underlying chromosphere and leave an imprint in the form of Moreton wave, due
to the enhanced pressure beneath their coronal wavefront. Despite the frequent
observations of coronal waves, their counterparts in the chromosphere are
rarely detected. Why the chromosphere rarely bears the imprints of solar
tsunamis remained a mystery since their discovery three decades ago. To resolve
this question, all coronal waves and associated Moreton waves in the last
decade have been initially surveyed, though the detection of Moreton waves
could be hampered by utilising the low-quality H$alpha$ data from Global
Oscillations Network Group. Here, we present 8 cases (including 5 in Appendix)
of the coexistence of coronal and Moreton waves in inclined eruptions where it
is argued that the extreme inclination is key to providing an answer to address
the question. For all these events, the lowest part of the coronal wavefront
near the solar surface appears very bright, and the simultaneous disturbances
in the solar transition region and the chromosphere predominantly occur beneath
the bright segment. Therefore, evidenced by observations, we propose a scenario
for the excitation mechanism of the coronal-Moreton waves in highly inclined
eruptions, in which the lowest part of a coronal wave can effectively disturb
the chromosphere even for a weak (e.g., B-class) solar flare.

Solar coronal waves frequently appear as bright disturbances that propagate
globally from the eruption center in the solar atmosphere, just like the
tsunamis in the ocean on Earth. Theoretically, coronal waves can sweep over the
underlying chromosphere and leave an imprint in the form of Moreton wave, due
to the enhanced pressure beneath their coronal wavefront. Despite the frequent
observations of coronal waves, their counterparts in the chromosphere are
rarely detected. Why the chromosphere rarely bears the imprints of solar
tsunamis remained a mystery since their discovery three decades ago. To resolve
this question, all coronal waves and associated Moreton waves in the last
decade have been initially surveyed, though the detection of Moreton waves
could be hampered by utilising the low-quality H$alpha$ data from Global
Oscillations Network Group. Here, we present 8 cases (including 5 in Appendix)
of the coexistence of coronal and Moreton waves in inclined eruptions where it
is argued that the extreme inclination is key to providing an answer to address
the question. For all these events, the lowest part of the coronal wavefront
near the solar surface appears very bright, and the simultaneous disturbances
in the solar transition region and the chromosphere predominantly occur beneath
the bright segment. Therefore, evidenced by observations, we propose a scenario
for the excitation mechanism of the coronal-Moreton waves in highly inclined
eruptions, in which the lowest part of a coronal wave can effectively disturb
the chromosphere even for a weak (e.g., B-class) solar flare.

http://arxiv.org/icons/sfx.gif