Noise Simulation on RPCs

Andrés Leonardo Cabrera MoraHigh Energy Physics GroupUniversidad de los Andes

¿What we are simulating?

Resistive Plate Chambers

Geometry

• Polyethylene (0.2 mm)• Graphite (0.2 mm)• Bakelite (2 mm)• Gas C2H2F4 (2 mm)• Aluminum (strips)(0.04

mm)• Air• Localized Electric Field

(4.5 kV/mm)

FIRST APROXIMATION

Implementation

• Particles: photons, electrons, positrons, muons and antimuons.

• Processes: Compton Scattering, Photo Electric Effect, Gamma Conversion, Multiple Scattering, Ionization, Bremsstrahlung, Positron Annihilation and Pair Production.

• Results: Histograms, Scatter Plots, Angles Distribution and Distance Distribution.

Conditions on the Simulation

• Incidence of ten millions of muons through a Double RPC (perpendicular, fixed point)

• Localized field in the region of the gas-4.5 kV/mm in the z axis (negative)

• The results show electrons that come from photons in the gas region

RESULTS

Counts

Distance Distribution X (cm)

Electron Distance Distribution

Counts

Energy Distribution (MeV)

Electron Energy Distribution

Angular Distribution

Z (positive)

Cos (Ѳ) = 1 Cos (Ѳ) = -1

Counts

Cos (Ѳ) Distribution

Electron Cos (Ѳ) Distribution

Counts

Φ Distribution (Deg)

Electron Φ Angular Distribution

X (mm)

Y (mm)

Scatter Plot Y vs X

OTHER RESULTS

Positive Electric Field

(4.5 kV/mm en la dirección positiva del eje z)

Negative Electric Field

(4.5 kV/mm en la dirección negativa del eje z)

RPC with Iron

RPC with aluminium

Change in the incidence of particles

• Distribution of energies • Incidence from different angles and points.

Manage of Information• Twiki in english/spanish

http://twiki.org/cgi-bin/view/Sandbox/AndresCabreraSandbox

Conclusions• The incidence of ten millions of muons

produce a 0.09% (9242) of electrons that come from photons.

• Only 0.09% (9) of electrons are produced to more than 10 cm of the point of incidence.

Conclusions

• Only 2.7% (257) electrons are produced to more than 2.4 cm (1.2 cm) of the point of incidence.

Counts

Distance Distribution X (cm)

Electron Distance Distribution