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The chromosphere above active regions (ARs) on the Sun hosts magnetizedsupersonic downflows. Studies of these supersonic downflows help to decipherthe magnetic fine structure and dynamics of the chromosphere. We perform astatistical analysis of the magnetized supersonic downflows in a number of ARsand survey their characteristics. We analyze spectro-polarimetric scans ofparts of 13 ARs obtained in the infrared He I 10830 \r{A} triplet formed in theupper chromosphere recorded with the GREGOR Infrared Spectrograph (GRIS)mounted at the GREGOR solar telescope. We retrieve the line-of-sight velocitiesand the magnetic field vector using the HeLIx+ inversion code that assumesMilne-Eddington atmospheres. We find magnetized supersonic downflows in all theARs, with larger area coverage by such flows in ARs observed during theiremerging phase. The fact that supersonic downflows were detected in all scans,though they cover only a small fraction, 0.2--6.4%, of the observedfield-of-view, suggests that they are a common phenomenon in the upperchromospheres of ARs. The supersonic downflows are found to be associated withmany AR features such as pores, sunspot umbrae, sunspot penumbrae, lightbridges, plages, He I loops as part of arch filament systems characteristic ofemerging fields, and filaments. Although several mechanisms are identified tobe causing the supersonic downflows, by far the most common one appears to bethe draining of plasma along the legs of rising magnetic loops. The loopsmainly drain into forming pores. The line-of-sight velocities of the supersonicdownflows reach up to 49 kms-1 and the velocity distribution shows multiplepopulations. Almost 92% of these supersonic downflows coexist with a subsonicflow component. The weaker, more horizontal fields associated with thesupersonic component suggests that it is formed above the subsonic component.

Magnetized supersonic downflows in the chromosphere. A statistical study using the He I 10830 \r{A} lines