IEAP CTU

Project CZELTA

Karel Smolek

IEAP CTU

13.2. 2009

2/14

Project CZELTA• CZEch Large-area Time coincidence Array – project of CTU and Silesian University in Opava.• Collaboration with Univ. of Alberta (project ALTA, we use the same hardware).• Project for the detection of high energy cosmic rays (>1014 eV).• Stations are installed at roofs of high schools -> educational impact .

Shower of particles of secondary cosmic rays.

3/14

Detection station

HV

PC

Scheme of the scintillating detector

U [

V]

t [ns]-50 0 50 100

-0.6

-0.5

-0.4

-0.3

-0.2

-0.1

0

channel 1channel 2channel 3

• 3 scintillators with photomultipliers in a triangle with a site ~10 m, work in a coincidence => detection of showers with the energy > 1014 eV.• GPS for precise time-labeling of detected showers (precision ~10 ns) => it is possible to study space and time coincidence of the detected showers.

Primary particle

Interaction in the atmosphere

Shower of secondary particles

4/14

Outer box with temperature insulation

Thermostat

Heating cableWooden box

With scintillating detector

Socket of 230 V (heating)

Thin metal tube with cable 230 V

Metal tube with other cables:- high voltage for photomultiplier- signal cables from photomultiplier- cable to testing LED diode- cable for controlling of thermostat

GPS antenna

Hardware of the detection station

5/14

PhotomultiplierLight guide

ScintillatorTesting LED diode

6/14

PCUPS

GPS receiver

Crates

Electronics

7/14

Station in Kladno

8/14

Meteorological station• Flux of detected showers is correlated with the atmospheric pressure.• We provide the detection stations with the meteorological station, measured data are automatically stored on PC.

• Collaboration with the Czech Hydrometeorological Institute – they provide us all necessary historical data measured with the professional stations. Disadvantage: for some detection stations, the professional station is not near.

9/14

Present situation of the project• Production of detection stations in the CR

electronic boards produced in Awos Pardubice scintillators produced in JINR Dubna in Russia

• First two stations installed in Prague and Opava: IEAP CTU – 2004 Silesian University in Opava – 2005

• Next three stations installed in high schools: High school in Pardubice - 2006 Mendel’s high school in Opava - 2006 High school in Kladno - 2007

10/14

Locations of detection stationsCZELTA stations

in the Czech Republic

station in operationstation in preparation

11/14

Web-based interface• New functionality added.

12/14

Web-based interface

13/14

Analysis of measured data• The aim is to build the global network of detection stations on the Earth = huge „telescope” for detection of cosmic rays showers.• In the measured data, unusual events are searched:

- sudden increase of rate of showers- simultaneous detection of showers with distant stations

• Minimal energy of a primary particle, which can produce a detectable shower of secondary particles: 1014 eV.• The timing resolution of the GPS time difference between distant sites: ~16 ns.• It is possible to reconstruct the direction of the flight of a primary particle.

Uncertainty of reconstructed altitude angle θ of a primary particle: δθ = 4°/sin(θ) Uncertainty of reconstructed azimuth angle φ of a primary particle: δφ = 5°

t

14/14

Conclusion

• Study of high energy cosmic rays is popular part of modern physical research.• At present, the Czech Republic is involved in the unique global project of detection of high energy cosmic rays.• The CZELTA project will help to solve present problems of cosmic rays.• Secondary purpose of the project is to attract young students from high schools to physics, mathematics and computer sciences.