DOI: 10.15129/b5697435-7651-4333-b00e-2ed2e072eb6a
title: Near-threshold electron injection in the laser-plasma wakefield accelerator leading to femtosecond bunches

description: NUMERICAL/EXPERIMENTAL DATA DESCRIPTION:
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These data files are readable and compatible to plot them with python plot, gnuplot, grace, etc..

___Figure 2
The parameter range for electron trapping solely due to the expanding bubble. The bubble expansion has been modelled 
as R(t)=R_0(1+\epsilon * t), where \epsilon is the expansion rate, R_0 is the initial bubble radius, 
and the bubble is spherically symmetric.

Fig2.txt
First column -&gt; expansion rate (\epsilon/\omega_p), second column -&gt; Bubble radius (R k_p), third column-&gt; Hamiltonian (m c^2)

___Figure 3
Analytical model for injection.

Fig3a-column.txt -&gt; contains all data for plot 3(a), i.e., z(t), x(t), gm(t), H(t)
Fig3b-column.txt -&gt; contains all data for plot 3(b), i.e., z(t), x(t), gm(t), H(t)
Fig3c-column.txt -&gt; contains all data for plot 3(c), i.e., z(t), x(t), gm(t), H(t)
Unexpanded  bubble shape data -&gt; Fig3-bubble1.txt
Expanded bubble shape data -&gt; Fig3-bubble2.txt

Figure 4

OSIRIS 3D simulation named "simulation-1". The simulation parameters are depicted in the paper.
             Bubble charge density-&gt; 
                         |Fig4a.txt    -&gt;   extent=(xk_p=-10,10, zk_p=295,315)
                         |Fig4b.txt    -&gt;   extent=(xk_p=-10,10, zk_p=590,610)
                          |Fig4c.txt    -&gt;   extent=(xk_p=-10,10, zk_p=689,709)
                         |Fig4d.txt    -&gt;   extent=(xk_p=-10,10, zk_p=788,808)

      Bubble potentials-&gt;    
                        |Fig4e.txt     -&gt;    extent=(xk_p=-10,10, zk_p=295,315)
                        |Fig4f.txt     -&gt;    extent=(xk_p=-10,10, zk_p=590,610)
                         |Fig4g.txt     -&gt;    extent=(xk_p=-10,10, zk_p=689,709)
                        |Fig4h.txt     -&gt;    extent=(xk_p=-10,10, zk_p=788,808)

___Figure 5
OSIRIS 3D simulations named "simulation-1 & simulation-2". Inputs files are:osiris-simulation1-input 
and osiris-simulation2-input.

           
|(a) Fig5-simulation1-a1.txt & Fig5-simulation1-a2.txt  -&gt; potentials
                               |(b) Fig5-simulation1-b.txt  -&gt; initial positions
Simulation-1 (left column)-&gt;   |(c) Fig5-simulation1-c.txt  -&gt; bubble length (k_p)
                               |(d) Fig5-simulation1-d.txt  -&gt; expansion rate (\epsilon/omega_p)
                               |(e) Fig5-simulation1-e.txt  -&gt; a_0
                               |(f) Fig5-simulation1-f.txt  -&gt; \gamma_b
                               |(g) Fig5-simulation1-g.txt  -&gt; \eta
                               |(h) Fig5-simulation1-h-bunch-length.txt
                               |    Fig5-simulation1-h-energy-spectrum.txt
                               |    Fig5-simulation1-h-z-energy.txt


                               |(a) Fig5-simulation2-a1.txt & Fig5-simulation2-a2.txt
                               |(b) Fig5-simulation2-b.txt 
Simulation-2 (right column)-&gt;  |(c) Fig5-simulation2-c.txt
                               |(d) Fig5-simulation2-d.txt
                               |(e) Fig5-simulation2-e.txt
                               |(f) Fig5-simulation2-f.txt
                               |(g) Fig5-simulation2-g.txt
                               |(h) Fig5-simulation2-h-bunch-length.txt
                               |    Fig5-simulation2-h-energy-spectrum.txt
                               |    Fig5-simulation2-h-z-energy.txt

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___Figure 7
Simulated spectrum of transition radiation after 1 m propagation from the accelerator produced by a two-foil system with separation 16 cm and a single Gaussian electron bunch with the following characteristics:

fig7_0.6um.txt
E0 = 100 MeV, 3% energy spread, 2 mrad divergence, 0.6 um bunch length

fig7_1.5mrad.txt
E0 = 100 MeV, 3% energy spread, 1.5 mrad divergence, 0.3 um bunch length

fig7_1es.txt
E0 = 100 MeV, 1% energy spread, 2 mrad divergence, 0.3 um bunch length

fig7_1es.txt
E0 = 100 MeV, 3% energy spread, 2 mrad divergence, 0.3 um bunch length
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__Figure 8
Simulated spectrum of transition radiation after 1 m propagation from the accelerator produced by a two-foil system with separation 16 cm and a composite electron bunch with the following structure:


Fig 8a (insets): OSIRIS simulations |Fig8a-simulation1-inset.txt
                                    |Fig8a-simulation2-inset.txt

fig8_ex1_tr1.txt
Two 100 MeV bunches separated by 11.5 ± 0.5 fs and with energy spread of 1%, charge of 8 pC and 3 pC and bunch length at the source of 0.9 fs

fig8_ex1_tr2.txt
Contains an additional 90 MeV bunch separated by 22 ± 2 fs from the first structure, 6% energy spread, 1.8 fs pulse duration and 0.5 pC charge

fig8_ex1_tr3.txt
Contains a fourth bunch separated by 45 ± 1 fs from the first structure, 3% energy spread, 1.8 fs pulse duration and 0.5 pC charge.

fig8_experimental1.txt
Spectrum of transition radiation measured experimentally showing at least two bunches.


fig8_ex1_tr1.txt
A 90 MeV bunch with energy spread of 6%, charge of 12 pC and bunch length at the source of 1.5 fs

fig8_ex1_tr2.txt
+ A 90 MeV bunch with energy spread 3%, charge 0.5 pC, bunch length 0.9 fs and 55 fs delay

fig8_ex1_tr3.txt
+ A 90 MeV bunch with energy spread 3%, charge 0.5 pC, bunch length 0.9 fs and 10 fs delay

fig8_experimental2.txt
Spectrum of transition radiation measured experimentally showing one bunch.
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