Beschreibung

# gnuplot
#
# use UTF-8 encoding for special characters
setencodingutf8

# create SVG output
setterminalsvgenhancedsize1000800fsize14
setoutput'KATRIN Spectrum.svg'

reset

# set aspect ratio to y:x = 0.8
setsizeratio0.8

# erase top and right borders (only show x- and y-axis)
setborder3
setxticsnomirror
setyticsnomirror

# set line styles for the three graphs
setstyleline1lt1lw1.5lcrgb"#cf0000"
setstyleline2lt1lw1.5lcrgb"#00cf00"
setstyleline3lt1lw1.5lcrgb"#0000cf"


## Constants
# alpha	 - fine-structure constant
# me	 - electron rest mass
# E0	 - endpoint of the Tritium beta-decay spectrum
# c	 - speed of light
# hbar	 - reduced Planck constant
# GF	 - Fermi coupling constant
# thetaC - Cabibbo angle
# Mnuc2	 - squared nuclear matrix element of Tritium beta-decay
# K	 - arbitrary scale factor
#
alpha=1/137.0
me=511.0e3
E0=18.6e3
#c	 = 2.99792458e8
#hbar	 = 6.58211928e-16
#GF	 = 1.16637e-5 * (hbar*c)**3
#thetaC	 = 13.4 * pi/180.0
#Mnuc2	 = 5.55
#K	 = 1/1.31529e74
K=1/1.03503e19

# the energy distribution for Tritium beta decay
# E - kinetic Energy
# E0 - Endpoint Energy
# me - electron rest mass
# mn - neutrino rest mass
# 
#
p(E)=sqrt((E+me)**2-me**2)
beta(E)=p(E)/(E+me)
A(E,Z)=2*pi*alpha*(Z+1)/beta(E)
F(E,Z)=A(E,Z)/(1-exp(-A(E,Z)))
R(E)=F(E,1)*p(E)*(E+me)*(E0-E)
N(E,mn)=K*R(E)*sqrt((E0-E)**2-mn**2)



###############################################################################

setmultiplot

# first multiplot piece -------------------------------------------------------

# use full frame for this plot
setorigin0.0,0.0
setsize1.0,1.0

# put legend in upper-left corner
setkeyrighttop

# use thinner lines for both axis
setborderlw0.5

# set zero threshold
setzero1e-2

# set x-axis parameters
setxrange[0:19]
setxtics2
setmxtics2
setformatx"%.0f"
setxlabel"Energy [keV]"

# set y-axis parameters
setyrange[0:1]
setytics0.2
setmytics2
setformaty"%.0l⋅10^{%L}"
setylabel"Intensity (count rate, arbitrary units)"

# set arrow showing the connection between the second multiplot and this graph
setarrow1fromgraph0.64,0.10tograph0.85,0.03lw1.5

# plot the graph for three neutrino masses
setsamples500
plotN(1000*x,1.0)title"m_ν = 1.0 eV"ls1,\
N(1000*x,0.3)title"m_ν = 0.3 eV"ls2,\
N(1000*x,0.0)title"m_ν = 0.0 eV"ls3


# second multiplot piece ------------------------------------------------------

# use half size of the diagram and put this plot inside the first one
setorigin0.12,0.12
setsize0.52,0.52

# disable legend here
unsetkey

# set x-axis parameters: here we use three decimal places and no label
setxrange[18.598:18.600]
setxtics0.001
setmxtics4
setformatx"%.3f"
setxlabel""

# set y-axis parameters
setyrange[0:4e-8]
setytics1e-8
setmytics2
setformaty"%.0l⋅10^{%L}"
setylabel""

# disable arrow from the first multiplot
setnoarrow1

# create a distance arrow between the end-points for m=0eV and m=1eV
setarrow11noheadfrom18.599,0.0to18.599,1.2e-8lw1
setarrow12noheadfrom18.600,0.0to18.600,1.2e-8lw1
setarrow13from18.600,1e-8to18.599,1e-8lw1
setarrow14from18.599,1e-8to18.600,1e-8lw1
setlabel"ΔE = 1.0 eV"at18.5995,1.2e-8center

# replot the graph with much higher sampling
setsamples1000
replot

#------------------------------------------------------------------------------

setnomultiplot
unsetoutput

## END OF FILE

Lizenz