New Studies on VPTs Setup RIE Photonis XPVPT25 Stefanie Bolte - PowerPoint PPT Presentation

New Studies on VPTs Stefanie Bolte Introduction New Studies on VPTs Setup RIE Photonis XPVPT25 Stefanie Bolte Hamamatsu R2148MOD1 Experimental Hadron Physics, Hamamatsu Ruhr-Universität Bochum R2148MOD Summary March 3rd, 2009 Outlook

Introduction New Studies on VPTs Electromagnetic Calorimeter Forward Endcap Stefanie Bolte Introduction Special needs for photodetectors because of Setup • magnetic field ⇒ no PMTs RIE • high rate ⇒ no APDs for innermost crystals Photonis XPVPT25 Hamamatsu ⇒ Photodetectors: R2148MOD1 sensitive, fast, radiation hard and suitable to operate in Hamamatsu R2148MOD magnetic fields Summary Outlook presentation of the new VPT type of Hamamatsu (<24 mm) and measurement concerning the sensitivity of the VPTs’ surface

Setup New Studies on VPTs • LED pulser ( f = 1 kHz) Stefanie Bolte • LUXEON1 High-Power LED Introduction λ = 455 nm Setup RIE • optical fibre transfers light Photonis pulses to VPT XPVPT25 • preamplifier behind VPT Hamamatsu R2148MOD1 transmits signal to Hamamatsu mainamplifier and R2148MOD Summary afterwards to ADC Outlook • preamplifier developed in Basel for PANDA

Technical Data New Studies on VPTs RIE Stefanie Bolte sample from the CMS experiment Introduction Setup • ∅ = 26 . 5 mm RIE ℓ = 40 mm Photonis XPVPT25 • U A = 1000 V Hamamatsu R2148MOD1 U D = 800 V Hamamatsu • G = 10 R2148MOD Summary • QE = 22 % Outlook (at 430 nm)

Sensitivity New Studies on VPTs • maximum in one corner Stefanie Bolte • yield varies between 750 Introduction and 1050 Setup • relative width 7.8 % RIE • sensitive area ∅ = 19 mm Photonis XPVPT25 Hamamatsu hist4 hist4 RIE Entries Entries 678 678 R2148MOD1 22 Mean 915.9 Mean 915.9 Counts RMS 71.13 RMS 71.13 20 18 Hamamatsu 16 R2148MOD 14 12 Summary 10 8 Outlook 6 4 2 0 750 800 850 900 950 1000 1050 Mean

Technical Data New Studies on VPTs Photonis XPVPT25 Stefanie Bolte latest sample from Photonis, made for PANDA Introduction Setup RIE • ∅ = 25 . 2 mm Photonis ℓ = 87 . 4 mm XPVPT25 Hamamatsu • U A = 1090 V R2148MOD1 U D = 763 V Hamamatsu R2148MOD • G = 30 Summary • QE = 20 % Outlook

Sensitivity New Studies • maximum and minimum on VPTs side by side Stefanie Bolte • yield varies between 500 Introduction and 2200 Setup RIE • relative width 22.1 % Photonis • sensitive area ∅ = 25 mm XPVPT25 Hamamatsu R2148MOD1 hist1 hist1 Photonis XPVPT SN31 Entries Entries 603 603 Mean 1728 Mean 1728 Counts RMS RMS 362 362 Hamamatsu 14 R2148MOD 12 Summary 10 8 Outlook 6 4 2 0 600 800 1000 1200 1400 1600 1800 2000 2200 Mean

Technical Data New Studies on VPTs Hamamatsu R2148MOD1 Stefanie Bolte sample from Rainer Novotny Introduction Setup • ∅ = 25 . 8 mm RIE ℓ = 30 mm Photonis XPVPT25 • U A = 800 V Hamamatsu R2148MOD1 U D = 640 V Hamamatsu • G = 11 R2148MOD Summary • QE = 19 % Outlook (at 440 nm)

Sensitivity New Studies • minimum in the middle, on VPTs maximum at the edge Stefanie Bolte • yield varies between 500 Introduction and 750 Setup RIE • relative width 9.2 % Photonis • sensitive area ∅ = 18 mm XPVPT25 Hamamatsu R2148MOD1 hist3 hist3 Hamamatsu R2148MOD1 Entries Entries 603 603 Mean 648.7 Mean 648.7 30 Counts RMS 59.69 RMS 59.69 Hamamatsu R2148MOD 25 20 Summary 15 Outlook 10 5 0 500 550 600 650 700 750 Mean

Technical Data New Studies on VPTs Hamamatsu R2148MOD Stefanie Bolte especially made for PANDA, ∅ < 24 mm Introduction Setup • ∅ = 23 . 7 mm RIE ℓ = 30 mm Photonis XPVPT25 • U A = 750 V Hamamatsu R2148MOD1 U D = 500 V Hamamatsu • G = 9.3 R2148MOD Summary • QE = 32 % Outlook (at 420 nm)

Sensitivity New Studies • minimum in the middle, on VPTs maximum at the edge Stefanie Bolte • yield varies between 850 Introduction and 1300 Setup RIE • relative width 7.4 % Photonis • sensitive area ∅ = 16 mm XPVPT25 Hamamatsu R2148MOD1 hist2 hist2 Hamamatsu R2148MOD Entries Entries 493 493 Mean 1110 Mean 1110 Counts 14 RMS 82.26 RMS 82.26 Hamamatsu R2148MOD 12 10 Summary 8 Outlook 6 4 2 0 850 900 950 1000105011001150120012501300 Mean

Summary New Studies on VPTs Stefanie Bolte RIE Photonis R2148MOD1 R2148MOD Introduction Setup HV 1000 V 1090 V 800 V 750 V RIE G 10 30 11 9.3 Photonis QE 22 % 20 % 19 % 32 % XPVPT25 26.5 mm 25.2 mm 25.8 mm 23.7 mm ∅ Hamamatsu R2148MOD1 19 mm 25 mm 18 mm 16 mm ∅ sen . area Hamamatsu rel. width 7.8 % 22.1 % 9.2 % 7.4 % R2148MOD G · QE 2.20 6.00 2.09 2.98 Summary AMP 916 1728 649 1110 Outlook AMP 1.1 0.8 0.8 1 G · QE

Outlook New Studies Vacuum Photo Tetrode (VPTT), made by RIE on VPTs Stefanie Bolte VPTT G ≥ 20 Introduction QE 25% Setup RIE G · QE > 3 . 0 Photonis 22 . 5 ± 0 . 7 mm ∅ XPVPT25 l ≤ 46 mm Hamamatsu R2148MOD1 ≥ 16 mm ∅ sen . area Hamamatsu R2148MOD What more has to be done? Summary • rate studies Outlook • influence of a magnetic field • temperature dependency