Interpenetration and stagnation in colliding laser plasmas

Mechanisms of carbon dimer formation in colliding laser-produced carbon plasmas

“…Laterally, colliding plasmas and cross-collisional plasmas are described in greater detail in the literature. 7,[9][10][11][12][13][14][15][16] Certain parameters dictate the manner of stagnation of the two colliding plasmas, namely, the characteristic plasma dimension (i.e., the separation between the colliding plumes) and the ion-ion mean free path. The "collisionality" parameter is the ratio of the plasma dimension to the ion-ion mean free path (f ¼ D/k ii ) and is given by…”

“…Colliding plasmas are currently a subject of interest in several plasma fields where their unique nature can give rise to optimal conditions for nanostructure formation 6 and EUV photon emission 7,8 or can lead to hard contamination of the chamber environment in an inertial fusion device. 9 For example, in inertial fusion devices, the thermonuclear burn of the DT pellet and the resulting products are contained by the first wall of these devices, which utilize carbon and other materials. The intense radiation and energetic ions produced in thermonuclear burn could vaporize the wall material, leading to low-temperature plasma converging toward the center of the reactor chamber.…”

“…15,16 Spectral images obtained across the visual range and within the narrow bandwidth belonging to specific ion and molecular vibration emission lines showed spatial evolution of stagnating plasmas produced from various target materials in different ambient conditions. 9 While the above measurements allow the accurate estimation of averaged parameters in the case of plasmas in local thermodynamic equilibrium (LTE), time-and spaceresolved plasma characteristics in the stagnation layer require a more detailed analysis. The above technique for plasma density and temperature measurement cannot be used for non-LTE conditions produced by higher intensities of laser beams.…”

The Effect of Confinement Angle on Self-Colliding Aluminium Laser Plasmas Using Spectrally Resolved Fast Imaging

“…The collisionality of the two plumes can be affected by modifying the target geometry [11][12][13][14]. Hence, different target configurations such as collinear [15][16][17][18][19][20], crossed [21] and orthogonal [22,23] geometries have been applied to investigate the collision process.…”

Effect of magnetic field on the laterally colliding plasma plumes

“…[1,[7][8][9][10] Colliding plasma with different targets, laser parameters, ambient and ablation geometries have been reported by several authors. [11][12][13][14][15][16][17][18][19][20][21][22][23][24] In our earlier work in aluminium colliding plasma we had found a clear distinct interaction zone and neutral emission is significantly enhanced at later times due to increase in three body recombination. [25] Plasma-plasma interaction in the presence of external magnetic field is an interesting phenomenon to study because of its implications from the understanding fundamental physics as well as applications.…”