Russian Federation
High-velocity clouds (HVC) with a total mass of ~7∙109 M○, settling into the Galaxy from its corona for ~109 years, can emit galactic fountains (T ~ 106 K). Giant molecular clouds (HMC) can form inside HVC. Crossing the rotating Galaxy ~5 times, HMC can eject fountains of gas (T ~ 105 K), as well as reproduce 5 spiral branches and chains of young stars, promoting star formation at 3 ± 1 M○ year-1. Most of the HMC settles at a distance of 4–8 kpc from the Galactic center, forming young stars whose high luminosity can overestimate the mass of this region (affecting the Galactic rotation curve) by up to 30%. HMC and HVC form shock waves with a size of 0.3 – 1 kpc with a power of ~4∙1041 erg/s, accelerating cosmic rays (CR) to ≤3∙1015 eV. Chains of HVC in the corona of Galaxy, collapsing into HVC complexes in its halo, can accelerate CR to ≤1018 eV; an ensemble of 2.5∙103 HMC can accelerate CR to ≤3∙1019 eV, Magellanic Stream – to ≤1020 eV.
high-velocity clouds, giant molecular clouds, galactic fountains, cosmic rays
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