Questions related to Laser Plasma Interaction
I am a research scholar I want to learn how to write a code for laser-plasma interaction simulation using python, if anybody helps me I am very thankful.
I want to learn the Particle in cell (PIC) simulation method for electron acceleration via laser plasma interaction. What will the best approach/application for the same?
EPOCH (Extendable Particle-in-cell (PIC) Open Collaboration) is a mature laser-plasma MPI simulation code that has a large international user base.
I need stark broadening parameters and life time of transitions of above mentioned lines for calculation of electron number density in laser produced Zn plasma and other spectroscopic parameters .
I need COMSOL code for simulation of intense laser plasma interaction and I want to expose this laser-produced plasma in an electric field to see double layering and then seed this laser-produced plasma with some external electrons
Where I can download COMSOL code for simulation of intense laser plasma interaction and seeding this laser-produced plasma with some external electrons?
I have 2 grating and I want to stretch or compress the pulse; if I know the initial pulse duration of pulse how I can calculate the final duration of pulse after stretching or compressing?
In the nanosecond ablation of metals in experimental conditions typically used for LIBS, the principal mechanisms of material removal are surface normal evaporation and phase explosion.
Which of these two mechanisms is better to establish the ablation stoichiometry and to create homogeneous plasma?
i need a book to explain detail process of interaction with formula and introduce that when we have pondermotive regime and when we have focusing and propagating of laser beam in plasma?
The cavity depth in isolated copper target is about twice as much compared with the sample with grounding (M. A. Sultanov, 1990)
I want to graft a monomer on the surface of another polymer by using electron beam technology. The problem is, there are variety of papers on this topic but I cannot find any article that explains the whole process in detail and the most important parameters that should be considered.
For instance, some of researchers covered the surface of polymer by a solution of the monomer, then irradiated by electron beam system, while others irradiated the surface of the polymer and then drenched the polymer into a monomer solution to graft it on the surface.
What is the phenomena behind these two different procedures?
Is there any difference between the outcomes of the two methods?
Additionally, I cannot find the irradiation time period required to do grafting? I thought it should be a crucial parameter when using Electron beam device.
In laser produced plasma. Do we see any difference in the the source size vertically and horizontally and why?
The depth of the keyhole welding in vacuum increases sharply (in nearly 3 times) compared with atmospheric conditions. There are not very convincing assumptions, but the real reason is stiil unknown.
In our recent optical shadowgraphy expts with soda lime glass target at 1013-1014 W/cm2 we noticed jets/filaments like structures in the target after a delay of 1, 2ns. Their velocity of propagation is 5x 107 Cm/s (for 1.4x1014 W/cm2 ) to 7x106 cm/s (for 5x1013 W/cm2)
To what factors I can attribute? ( I have attached two pictures along with a reference shadowgraph. and a time integrated (He-Ne laser) in which first one after 2ns 5x1013 and second one at 1ns at 1.4x1014 W/cm2
( In images 2,3,4 heating laser is incident from left side. The shock is propagating rightwards. The image 1 is 90 deg rotated where the laser is incident from top, shock expanding downwards) The big cloud is the shock front. the front channels are the structures we are referring to, they look collimated,aren't they?)
In literature I noticed that,
- Fedosejevs (JAP52,4186, PRA 32,3535) attributed it to electrical breakdown. but the difference between these two observations is theirs is like a 'cloud' expanded to 500 microns at 0.76ns much wider compared our collimated.
- Gremillet (PRL,83,5015) observed similar collimated filaments but much faster (c) at much earlier times(1,2ps) of course at 1019 W/cm2. In contrast our collimated structures travel at much lower velocities.they attributed it to presence of self generated magnetic fields. They say 'interplay of magnetic focusing and collisonless pressure effects may result in a self-guiding regime in tenuous plasmas'. Does the same logic hold good at much lower velocities?
Thanks in advance for any possible leads.
Is diffraction limited performance a good starting point for lasers in laser produced plasma. Say if we have a 3x diffraction limit, how does the intensity on target changes?
We are applying an 800 nm Ti:Sa laser with 60 fs pulse length FWHM.
My problem is, that normally damage thresholds are given in total pulse energy or fluence which lack information about peak irradiance. For ns-Pulses this should be a sufficient information, but is for fs pulses a clearly too loose condition as peak irradiance values can be much higher in this case.
How can I estimate a proper damage threshold condition ?
Are there publications that I miss which might help me ?
Thank you for your help.
Atmospheric pressure, non-thermal plasma jets are increasingly used in many processing applications, due to their combination of inherent plasma stability and excellent reaction chemistry, which is often enhanced downstream of
the plasma source.
It is important to underline, that due to the high industrial demand for plasma
technologies and the resulting competition between system manufacturers, many of these manufacturers come to the market with closed box plasma systems (typically a plasma generator and its matching network in the single box), which
cannot be opened due to warranty issues. This leads to the situation where the only plasma diagnostic techniques available are optical techniques. Under these circumstances it is very challenging to develop an experimental approach, which would give a fundamental explanation of the impact of plasma physics on atomic physics, e.g., the role of metastable atoms, resonance energy levels, triplet and singlet energy scale, life time of electrons in an excited atom/molecular state, etc.
As we know LIBS is mainly used for the elemental analysis of a material. Is it possible to use femto-second and atto-second lasers? If it is possible then which is a suitable technique and why? Is there any papers related to the elemental analysis by femto-second and atto-second lasers technique? Please give the reference also. Thanks.
The non uniform laser profile of the laser beam is responsible for the density redistribution in the Plasma and in the region where intensity is locally higher the ponderomotive force pushes plasma away. Due to this, plasma refractive index seen by the laser beam also gets modified which leads to further focusing of the laser beam and hence enhancing the initial fluctuation in intensity profile. This positive feedback gives rise to instability which can create a hindrance in symmetrical compression of pallet in the laser driven ICF. So Both SRS and SBS along with the filamentation instability do greatly affect the ICF efficiency. Which process will be suppressed drastically and why?
A radio device receives many signal frequencies at night from broadcasting stations even coming from far countries, while this phenomenon disappears during the daytime. Perhaps, ionosphere is responsible because solar UV radiation (SUVR) usually enhances the ionization rate whereas SUVR is absent at night. It may be denser in daytime and dilute or weak plasma at night. Then, the electromagnetic wave interaction with plasma may explain this fact.
I use the sesame EOS library of CH and DT in my simulation. In many articles about of simulation of ICF, the target is made of three or four layers (DT gas, DT ice , CH(DT)n). How to make an EOS table for CH(DT)6 or CH(DT)n?