1 / 9

The g- background of C ALIFA CsI(Tl) elements

The g- background of C ALIFA CsI(Tl) elements. Crystals produced by Amcrys Ltd., Khar’kov (Ukraine). C ALIFA - 90º elements 10x30x 130 x15x42 mm**3. Forward Cap elements?? 20x20x 210 x26x26 mm**3.

shana
Download Presentation

The g- background of C ALIFA CsI(Tl) elements

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. The g- background of CALIFA CsI(Tl) elements Crystals produced by Amcrys Ltd., Khar’kov (Ukraine) CALIFA - 90º elements 10x30x130x15x42 mm**3 Forward Cap elements?? 20x20x210x26x26 mm**3 for detailed description of CALIFA elements, see CWG video report Feb 26,2008 by V. Avdeichikov

  2. Calorimeters for HEP. Amcrys Ltd production CsI(Tl) BELLE (KEK) barrel 4640 pcs. 22.52 tons endcap 1506 pcs. 7.87 tons BaBar (SLAC) barrel 1643 pcs. 6.281tons endcap 216 pcs. 0.78 tons

  3. CsI(Tl)/APD (10x10), Energy resolution for g-rays. Batch of 8 CsI. 12 CsI(Tl) Khar’kov samples ( <M>=50, ALICE Preamp., shapingtime = 2 ms) Our data <M>=100 M.Moszynski CsI(Tl)/0.8 cm**3 V.Avdeichikov, NUSTAR meeting GSIJan-08

  4. CsI(Tl)/APD in CALIFA-4 samples 0.6% Protons 0.4% Gammas • Whole CsI(Tl) volume is irradiated. LO non-uniformity for tested crystals have been modified to 0.15 – 0.28% • Original LO inside one batch energy resolution 10% - 15% • 44-51% of Light is collected by the lightguide • We are close to the limit in R% • (Solid lines is driven to guide an eye) • (Shaping time – 2 ms) t=2.0 ms CWG meeting April 08

  5. Extra long, 210 mm, CsI(Tl) crystals 20x20x210x26x26 mm**3 Option forForward Cap?? for the EXL setup?? 26x26 20x20 10x10 L=210 mm, V=110 cm^3 Some preliminary test results…..

  6. CsI(Tl)/APD(10x10) <M> = 50 10 % 9 , n 0.660 8 o i t 0.569 7 u l o s 6 1.063 MeV e R 5 y 1.33 g r e n 4 E 2.50 3 0 1 x 2 0 1 6 2 x CsI(Tl) 6 0 2 2 x 0 APD 2 l = 210 mm 1 600 800 1000 2000 3000 4000 Collected Light, channels Energy resolution of 210 mm CsI(Tl)/APD elements for g-rays. 3 elements measured. LO uniformity = (0.5-1.0)% k k k 5000 Energy resolution of 130 mm CsI(Tl)/APD elements for g-rays. 12 elements measured LO uniformity = (0.30 – 0.70)%

  7. g-background counting rate for CALIFA-5 element with Eg> 50 keV Noise tail?? Al, 1 mm Pb, 40 mm Threshold will depend on light collection. For Califa CsI/APD(10x10) the Light Collection is around 44-51%. Spectroscopic threshold, in average, 25 keV(see next slide) For Califa CsI/PMT element threshold, in average, 10keV

  8. Natural g-background for 6000 Califa elements equal to 1.0*10^6 events/sec ( > 50 keV). What is the trigger structure?? Califa-5 element. Spectrum of Am241 X-line ( 59.5 keV). Spectroscopic threshold around 25 keV g-background, accumulated during2 hours, low-energy part, 170 1/sec Spectroscopic threshold – 25 keV Noise – 8.7 keV (FWHM) for 44-51% of Light Collection. 10x30x130x15x42 mm**3 CsI(Tl) Noise – 4.3 keV (FWHM) - Moszynski., NIMA 485(2002)504 in case of 100% of Light Collection. 0.8x10x10 mm**2 CsI(Tl) .Threshold –10 keV A threshold of 100 keV  a large reduction of background

  9. Other points to be raised for discussion (LU, 16 April 2008) • The possible use of PD+PA(ALICE/PHOS) • - The optional choice of 210 cm CsI(Tl) for forward cap • The in-beam tests at TLS and TDU • The DEMONSTRATOR(s) and their interface to Si tracker, FEE and DAQ CWG, 16 April 08, LU

More Related