SLIDE 1 Presentation of Activities
Institute of Physics Academy of Sciences of the Czech Republic Prague 6, Cukrovarnicka 10 Czech Republic amares@fzu.cz
SLIDE 2 Experimental set-up for scintillation response studies using HPMT
5 10 15 20 25 30 200 300 400 500 600 700 800 Quantum efficiency of the HPMT DEP Q.E. [%] Wavelength [nm]
ORTEC model 672 MCA ORTEC Model 927 MCB
Pulsed height spectra
241Am (59.6 keV) excited lines of
Cu, Rb, Mo, Ag, Ba, and Tb,
57Co, 22Na, 137Cs and 60Co
Here, we use α-ray sources instead of γ-rays
α-ray sources –
241Am, 239Pu
and 244Cm
SLIDE 3 1 10 100 1000 104 105 106 107 108 100 200 300 400 500 no bias -no voltage 20 V bias - 6 kV 40 V bias - 6 kV 40 V bias - 10 kV 40 V bias - 12 kV long Counts Channel number n = 1 n = 2 n = 3 n = 4
Photoelectron response of the HPMT ➣ Bias – voltage at the Si PIN diode anode ➣ High voltage – between the photocathode focusing electrodes and the anode SIGNAL
no voltage dark current, light
HV voltage – signal appear
voltage photoelectrons appear calibration is possible
SLIDE 4 1000 2000 3000 4000 5000 6000 1 mm 2 mm 5 mm 10 mm Counts Channel number 600 500 400 300 200 100 Sample thickness Arrows - 662 keV peak position
Gamma-ray pulse spectra of 662 keV line of the 137Cs source with YAG:Ce measured for different sample thickness
These gamma-ray spektra show that
has lower photo-peak efficiency compared with LuAG:Ce (photo- peak/Compton edge ~ 0.26 for 10 mm thickness) due to lower density (4.55 g/cm3) it is necessary to use longer crystals (lower attenuation than has LuAG:Ce)
- YAG:Ce could be efficient for detection with the avalanche photodiodes
SLIDE 5 HPMT se-up at CERN developed during late nineties
scintillation characteristics
SLIDE 6
Carmelo D’ Ambrosio shows the HPMT set-up Carmelo Jiri
SLIDE 7 Measurements at CERN –
SLIDE 8 HPMT scintillation set-up at the Laboratory
Luminescence and Scintillation Materials in Prague
SLIDE 9
PHOS – photon calorimeter
Gamma a alfa spektroskopie scintilátorů
FZÚ – Department of Optical Materials – study of scintillation crystals RD-18 project – “Search for new radiation hard scintillators for new generation of electromagnetic calorimeters at LHC” Crystals: Ce-, Pr-doped garnets, perovskites, silicates. PbWO4 and other ones
Projects are supported by the Czech Committee for cooperation with CERN (from Ministry of Trade and Industry or later by Ministry of education, Youth and Sport
SLIDE 10 All-Russian Science Research Institute of the Experimental Physics - VNIIEF
MECHANICAL DESIGN of the PHOS CRADLE MECHANICAL DESIGN of the PHOS CRADLE
General information General information
The overall dimensions
The total weight is around 3,5 t
PHOS CRADLE Project - schema
SLIDE 11
End of 2004 year – CRADLE produced at TENEZ factory in Chotebor, Czech Republic
SLIDE 12
JUNE 2005 - PHOS CRADLE assembled at CERN Point 2 by people from TENEZ factory
TENEZ people
MARES
SLIDE 13
PHOS CRADLE is moving down into experimental position – CERN, Point 2, St. Genis
Rollers CRADLE
SLIDE 14
PHOS CRADLE in the final position below the collision space of ALICE LHC experiment
PHOS CRADLE
SLIDE 15
PHOS CRADLE position – November 2008 – Point 2 ALICE LHC
SLIDE 16
Detail of PHOS CRADLE – November 2008 – ALICE LHC
SLIDE 17
Works on or around PHOS CRADLE are not easy
SLIDE 18
CERN – Point 2 – ALICE LHC space – with Martin Faltys Jiri Martin
SLIDE 19
One PWO module is in the centre of PHOS CRADLE holder module
SLIDE 20
Dmitry Budnikov from Sarov Jiri from Praha With Dmitry Budnikov from VNIIEF in Sarov at PHOS assembling hall at CERN
SLIDE 21
With Karel Polak at the read side of one PHOS PWO module at the assembling hall at CERN Karel Polak Jiri Mares
SLIDE 22 Front side of one of the PHOS PWO modules
- individual PWO crystals are clearly seen
SLIDE 23
CERN - November 2009 – control screen of PHOS detector at the ALICE CONTROL ROOM at Point 2
SLIDE 24
CERN - Point 2– November 2009 – ALICE CONTROL ROOM - PHOS CONTROL Petr Zavada Jiri Mares
SLIDE 25
CERN – Point 2 – November 2009 - PHOS control New start of LHC and first collisions
SLIDE 26
CERN – Point 2 – ALICE CONTROL ROOM – first collision November 23, 2009
SLIDE 27
CERN – Point 2 – ALICE CONTROL ROOM – people see first ciollisions
SLIDE 28
CERN – picture of inner part of LHC, especially Of magnets
