Projectile

About: Projectile is a research topic. Over the lifetime, 13047 publications have been published within this topic receiving 115563 citations.

Fragmentation of ice by low velocity impact

Abstract: Low velocity impact experiments (014 to l km/s) carried out in polycrystalline water ice targets at 257 and 81 K resulted in interactions which can be assigned to four fragmentation classes, cratering, erosion, disruption, and total fragmentation Specific kinetic energies for the transitions between these classes range from l x 10^5 to 7 x 10^5 ergs/g for 81 K ice and from 3 x 10^5 to ~ 2 x 10^6 ergs/g for 257 K ice These values are about one to two orders of magnitude below those for silicate rocks The mass vs cumulative number distribution of fragments in our experiments can be described by a simple power law, similar to that observed in fragmented rocks in both the laboratory and in nature The logarithmic slopes of cumulative number vs fragment weight vary between - 09 and - 18 decreasing with increasing projectile energy and are approximately independent of target temperature The shapes of fragments resulting from erosion and disruption of ice targets are significantly less spherical for 257 K targets than for 81 K targets Fragment sphericity increases with increasing projectile energy at 257 K, but no similar trend is observed for 81 K ice Our results support the hypothesis that the specific projectile energy is a measure for target comminution for a relatively wide range of projectile energies and target masses We apply our results to the collisional interaction of icy planetary bodies and find that the complete destruction of a target body with radii between 50 m and 100 km· range from 10^(17) to 10^(27) ergs Energies corresponding to basaltic bodies of the same size range from 10^(18) to 10^(28) ergs Our experiments suggest that regolith components on icy planets resemble those on rocky planetary bodies in size and shape We predict that the initial shapes of icy particles in the Saturnian ring system were roughly spherical The initial mass distribution of ring particles should follow a power law with a slope of ~ - 15

Projectile and cartridge arrangement

Abstract: A projectile having a guard ring of circumferentially spaced posts encompassing a convex nose rupture disc and web. The projectile is mounted in a case with the nose extending in exposed condition beyond the open case end. A dual diameter chamber high-low propellant firing and gas expansion arrangement is utilized in the cartridge in conjunction with the reduced diameter tapered and finned rear end of the projectile.

Selective production of Auger electrons from fast projectile ions studied by zero-degree Auger spectroscopy

Abstract: Projectile L-Auger electrons were measured with high resolution in collision of 91.6 MeV Arq+ on gaseous target atoms (H2, He, Ne). Kinematic (Doppler) broadening effects were significantly reduced by observing the Auger electrons at an angle of zero degrees. Light target atoms were used to avoid considerable changes in the outer shell of the projectile during L-shell ionisation. Thus, the predominant excitations of the configurations 1s22s22p53s23p and 1s22s22p53s2 are achieved for incident Ar5+ and Ar6+, respectively.