Jean Favier LAPP PART 1: Particles generation in GEANT (3.2) ( IN PROGRESS…) Problems with Geant to reproduce in the same time electrons and the good relativistic rise for dE/dX ( We keep the coodinates of each energy deposite Volume =200*200*44 3 (one layer ) ) To get a density of 30 grains/100 en mean for mip, I eliminate randomly points. ( same result than to discriminate on energy deposite)
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Jean Favier LAPP GenIma: program to simulate emulsions
Introduction GEANT : GENerate tracks and grains IMA: makes pictures
Examples Conclusions Jean Favier LAPP Introduction The lack of data
for various conditions ( particle type, angles, energies, fog
densities, integration times, etc) and a poor statistics make
difficult the reconstruction programs optimization. The large
feed-back time between beam tests and scanning is responsible for
these difficulties. It was attracting to reproduce emulsions data
by Monte- Carlo, as for the other detectors, with the hope to
increase the comprehension of the parameters influence, and to
permit an optimization of the designing of future beam tests. Jean
Favier LAPP PART 1: Particles generation in GEANT (3.2) ( IN
PROGRESS) Problems with Geant to reproduce in the same time
electrons and the good relativistic rise for dE/dX ( We keep the
coodinates of each energy deposite Volume =200*200*44 3 (one layer
) ) To get a density of 30 grains/100 en mean for mip, I eliminate
randomly points. ( same result than to discriminate on energy
deposite) Jean Favier LAPP Grain x,y,z Pixels filling zone density
=f(r) in plan i r Optical axis = focusing angle = arcsin(N.A/n)
Jean Favier LAPP PART 2 In a separate program: For each grain x,y,z
we calculate intercepted surfaces by conical expansions backward
and upward, isolating zones of pixels to fill. The cone aperture is
determined by the lense parameters : = arcsin(N.A/n refr ) Pixels
are filled with grey in each of the 16 picture planes; grey
densities vary with the grain-plane distance( 1/d 2 et e -d/ ou
=longueur dabsorption optique de lemulsion). Size of grains is
obtained by an appropiate smearing Field is 200200 for 1024 1024
pixels, 16 planes; cone angle is 36 0 (pure Liban cedar oil), or 64
0 (air) Then add the wanted amount of random fog (6 grains/ (10 ) 3
) and expand them also. Pictures are written in Fortran (PPM
format), then converted in JPEG with XView. Jean Favier LAPP Format
PPM http//cedric.cnam.fr/~gouet/Var/ppm.html #Example: toto.ppm P #
red green blue Jean Favier LAPP Oil and air (without fog) N.A=nsin(
) n=1. ou 1.52 = 64 0 ou 36 0 Jean Favier LAPP Electrons tracks 0
to 1 Mev 20 0 horizontal, fog= 6/1000 3 Jean Imad Jean Favier LAPP
Emulsion simulation 16 images Jean Favier LAPP Emulsion simulation
16 images Jean Favier LAPP Emulsion simulation Jean Favier LAPP
Emulsion simulation 16 images Jean Favier LAPP Emulsion simulation
16 images Jean Favier LAPP Emulsion simulation 16 images Jean
Favier LAPP Emulsion simulation 16 images Jean Favier LAPP Emulsion
simulation 16 images Jean Favier LAPP Emulsion simulation 16 images
Jean Favier LAPP Emulsion simulation 16 images Jean Favier LAPP
Emulsion simulation 16 images Jean Favier LAPP Emulsion simulation
16 images Jean Favier LAPP Emulsion simulation 16 images Jean
Favier LAPP Emulsion simulation 16 images Jean Favier LAPP Emulsion
simulation 16 images Jean Favier LAPP Find the vertex ! : 5 muons
emerging from a point at 17 microns depth Jean Favier LAPP Next
steps Improve grain density = f(dE/dX), saturations, rays add the
second layer Interface with microscope software Compare with
available data ( ex: eff=f(angle) ) Version root, C++ ?
Documentation Album of various backgrounds (compton + fog,
refreshing actions) Distorsion simulation Lyon inclined
geometry?
