Bayesian inference of plasma parameters from collective Thomson scattering technique on a gas-puff near stagnation

Escalona, M.; Valenzuela, J. C.; Avaria, G.; Veloso, F.; Wyndham, E. S.

Abstract

The Collective Thomson scattering technique has been implemented to study the stagnation of a single liner gas-puff. The plasma parameters are determined by theoretically modelling the scattering form factor in combination with Bayesian inference to provide the set of the most probable parameters that describe the experimental data. Analysis of the data reveal that incoming flows are able to interpenetrate partially. Estimation of the mean free path shows a gradual transition from a weakly collisional to a collisional regime as the plasma gets to the axis. Furthermore, we find that the ion energy at r = 2.5 mm is 13.6(-0.9)(+1.0) keV and is mostly kinetic in nature and represents 98(+10) (-9) % of the total energy. This kinetic energy is far greater than the value on axis of 3.7(-0.5)(+0.4) keV which is 84(-14)(+15) % of the total energy. Energy transfer to the electrons and radiation losses are found to be negligible by this time. A possible explanation for this energy imbalance is the presence of an azimuthal magnetic field larger than similar to 4.7 T that deflect the ions vertically. The uncertainties quoted represent 68% credible intervals.

Más información

Título según WOS: ID WOS:001049382700030 Not found in local WOS DB
Título de la Revista: Scientific Reports
Volumen: 13
Número: 1
Editorial: NATURE PORTFOLIO
Fecha de publicación: 2023
DOI:

10.1038/s41598-023-40014-x

Notas: ISI