1. Simulations of the response of the KLOE electromagnetic
calorimeter using a FLUKA package
Frascati Spring School
J.J. Zdebik, B. Di Micco, P. Moskal

2. PLAN
1. Introduction - physic motivation
2. Geometry implementation with FLUKA
and results of simulations with jjpluto:
- one calorimeter module
- the whole kloe barrel calorimeter geometry

3. 1. Introduction - physic motivation
We implement the barrel calorimeter geometry to fluka package
because we want to simulate as realistic response of the detector as possible.
Main purpose: the implementation more detailed geometry
with the smallest parts of detector (fibers structure)
Fluka simulation is mostly used in low energy hadronic interaction, medical science, dose evaluation, neutriono beam simulation.
Kloe with its particle spectra up to 1 GeV can, in principle, have a more accurate description of the detector physics with FLUKA.

4. The KLOE Barrel Calorimeter

5. simulation of lead-scintillator layers (GEANT3)
2. Geometry
implementation.
FLUKA and KLOE MC - differences
simulation of lead-scintillator layers (GEANT3)
One module of the calorimeter
lead layer
scintilator layer

6. implementation of the smallest parts of the calorimeter layers:
FLUKA and KLOE MC - differences
implementation of the smallest parts
of the calorimeter layers:
active material (fiber) and passive (glue, lead foil)...
LEAD
385 fibers in one layer
GLUE
FIBRES
... and photoelectrons statistic of PMs

7. Previous situation: Rectangular module implemented 200 Layers
1 LAYER REPLICATED 200
TIMES USING LATTICE TOOL
First Fluka version
(G. Battistoni, B. Di Micco, A. Ferrari, A. Passeri, V. Patera)

8. Fluka structure visualisation
Visualization performed using the FLAIR package
Z [cm]
base cell
X [cm]

9. Implementation of the one calorimeter module
First approach:
1). define a new base cell: 1 glue cylinder,
1 fiber cylinder, 1 lead box
New base cell.
Replicated ~4000 times to design
the triangular sections.
previous structure
New areas
Number of regions: ~4500
The geometry file has got:
21230 lines

10. Implementation of the one calorimeter module
CALORIMETER: TRAPESOID MODULE

11. Implementation of the one calorimeter module
How it works?
Building material by FLUKA in replicated areas in „fly”
TRANSPORT
FROM BASE CELL
TO REPLICATED
AREA
PARTICLE TRACK
TRANSFORMATION
TO BASE CELL
AND
TRANSPORT
PARTICLE IN
MATERIAL
PARTICLE TRACK

12. e+e- → φ →  → 000 → 
Vertex generator implemented (jjpluto), reproducing the processes:
e+e- → φ →  →
e+e- → φ → 0 → 
e+e- → φ →  → 000 → 
e+e- → φ → Ks Kl
e+e- → φ → K+ K-
e+e- → φ → '  → 
e+e- → φ → '  → 000 → 
a simulation based on GENBOD
(phase space generator - from Cern libraries)

13. e+e- → φ →  → e+e- → φ → 0 →  e+e- → φ → 
JJpluto vs kloe data comparision
e+e- → φ → 0 → 
e+e- → φ →  →
e+e- → φ → 
KLOE EXPERIMENTAL DATA
SIMULATIONS WITH JJPLUTO

14. Implementation of the one calorimeter module: Coordinate system
beam axis

15. e+e- → φ →  → 000 → 
Implementation of the one calorimeter module: ENERGY DEPOSITIONS
e+e- → φ →  → 000 → 
1000 events
20000 events

16. e+e- → φ →  → 000 → 
Position of particles at calorimeter entrance haven been
stored using BXDRAW routine in mgdraw.f (Boundary crossing drawing)
e+e- → φ →  → 000 → 
events

17. e+e- → φ →  → 000 → 
Position of particles at calorimeter entrance haven been
stored using BXDRAW routine in mgdraw.f
events
e+e- → φ →  → 000 → 

18. Implementation of the whole barrel calorimeter
Comments:
1) The simplest solution. The FLUKA barrel is the replication of a single module;
2) problems: Impossible to do in the present version (lattice of lattices is
not implemented).
Upgrade of FLUKA version requested to the authors
3) Code already available and running.
We are waiting for new FLUKA release for this approach.
At the meanwhile we implemented of the barrel
calorimeter geometry in another way:

19. Implementation of the whole barrel calorimeter: Visualisation with Flair
BASE CELL
The rest conatiners are
replicated areas
(lattice areas)
24 modules of geometry:
59810 lines
bodies:
5214 regions
Structure of base cell:
Lattices
Base cells

20. Implementation of the whole barrel calorimeter

21. Implementation of the whole barrel calorimeter: Lattic replication
ROTATION TO
TRAPES 1
TRANSLATION
TO MATERIAL
AREA
PARTICLE
TRACK
INTERACTION AND
ENERGY DEPOSITING

22. Implementation of the whole barrel calorimeter: Lattic replication
ROTATION TO
FIBER STRUCTURE
AND INTERACTION WITH MATERIAL
PARTICLE
TRACK

23. Implementation of the one calorimeter module
Fibers structure

24. e+e- → φ →  → 000 → 
Implementation of the whole barrel calorimeter:
Energy deposits on the geometry
Events:
1000
e+e- → φ →  → 000 → 

25. Implementation of the whole barrel calorimeter:
Energy deposits on the edge of two modules
Statistic:
events

26. e+e- → φ →  → 000 → 
Implementation of the whole barrel calorimeter:
Energy deposits on the geometry - one event only
e+e- → φ →  → 000 → 
Merging effect g
Splitting effect g g g g g g

27. Implementation of the whole barrel calorimeter
Thanks for attention