Related Experiment Video
Updated: May 17, 2026

Investigation of Early Plasma Evolution Induced by Ultrashort Laser Pulses
Published on: July 2, 2012
Comparison of azimuthal ion velocity profiles using Mach probes, time delay estimation, and laser induced
S Chakraborty Thakur1, D McCarren, T Lee
1Center for Momentum Transport and Flow Organization, University of California at San Diego, 92093, USA. saikat@ucsd.edu
Abstract:
We compare measurements of radially sheared azimuthal plasma flow based on time delay estimation (TDE) between two spatially separated Langmuir probes, Mach probes and laser induced fluorescence (LIF). TDE measurements cannot distinguish between ion fluid velocities and phase velocities. TDE and Mach probes are perturbative, so we compare the results against LIF, a non-perturbative, spatially resolved diagnostic technique that provides direct measurements of the ion velocity distribution functions. The bulk ion flow is determined from the Doppler shift of the Argon absorption line at 668.6139 nm. We compare results from all the three diagnostics, at various magnetic fields, which acts as a control knob for development of drift wave turbulence. We find that while Mach probes and LIF give similar profiles, TDE measurements typically overestimate the velocities and are also sensitive to the drift wave modes being investigated.
Related Concept Videos
Inductively Coupled Plasma Atomic Emission Spectroscopy: Instrumentation
There are three main types of inductively coupled plasma atomic emission spectroscopy (ICP-AES) instruments: sequential, simultaneous multichannel, and Fourier transform instruments, with the latter being less commonly used.
Inductively Coupled Plasma–Mass Spectrometry (ICP–MS): Overview
Inductively Coupled Plasma Atomic Emission Spectroscopy: Principle
The ions and electrons produced interact with the fluctuating magnetic field created by a water-cooled...
Mass Analyzers: Common Types
Atomic Emission Spectroscopy: Lab
Atomic Emission Spectroscopy: Instrumentation

