CMS HF PMT SYSTEM By Y. ONEL U. of Iowa, Iowa City, IA CMS HCAL at Fermilab Feb 6-8, 2003

CMS-HF PMT Test and Quality Control System U. Akgun 1, A.S. Ayan 1, F. Duru 1, E. Gulmez 2, M. Miller 1, J. Olson 1 Y. Onel 1, I. Schmidt 1 with Quarknet Group – P. Bruecken, C. Like, R. Newland 1 University of Iowa, Iowa City, USA 2 Bogazici University, Istanbul, Turkey Abstract We have measured the specifications proposed by the CMS-HCAL committee on the candidate phototubes from the three major manufacturers; Hamamatsu, EMI and Photonis. In this report, we present the results from those measurements and we outline the future measurements for the test and the quality control as well as the design of the new University of Iowa PMT test station facility.

Tasks of the Test System For one tube in every batch: Double-pulse linearity, Gain vs HV for each batch Single photoelectron spectrum X-Y scan (spatial uniformity) Lifetime For each tube: Pulse width Pulse rise time Transit time Transit time spread Anode dark current Relative gain coupled with cathode sensitivity, Pulse linearity Quality control decision on each tube.

Iowa PMT Timing Test Setup

UNIVERSITY of IOWA PMT TEST STATION

XY Uniformity, Dark Current, Relative Gain 32 channel Voltage ADC Motor Controller LabVIEW Software SCSI Bus Serial Bus 8-PMT Array Laser Pinhole Mask Camac Sys 8 channel pico-ammeter

Single Photoelectron Setup (fourth generation)

LabVIEW software

PMT Timing Data (1900 PMT’s)

PMT Data (1900 PMT’s)

CA0058 Double Pulse Linearity

Single Photoelectron Spectrum at 1100V

Single Photoelectron Spectrum at 1500V

XY Uniformity

Relative Gain vs Gain

Gain vs HV for Relative Gain %50-%70

Gain vs HV for Relative Gain %70-%80

Gain vs HV for Relative Gain %80-%90

Relative Gain vs Relative QE

Relative Gain & Relative QE

Lifetime Measurement Setup

Timing characteristics after 1100 C 0472 Pulse WidthRise TimeAv. Transit TimeTransit Time Spread Before 3.74ns2.02ns15.5ns0.148ns After 3.74ns2.14ns15.4ns0.173ns 0252 Pulse WidthRise TimeAv. Transit TimeTransit Time Spread Before 4.12ns1.98ns15.5ns0.094ns After 3.8ns2.12ns15.4ns0.174ns

PMT Web Database Sort by column (Ascending or Descending) Pagination reference for large data sets Alternating colors to aid readability More extensive search/sort options are being developed

PMT Web Database

PMT Base Comparison Hamamatsu’s Resistive Base Cockroft-Walton Base Parallel-Dynode Bases

Preliminary Base Comparison Results

HCAL LED Pulser

HF LED Pulser

HF LED Pulser Output of Prototype 10 ns/div Electrical Signal Degradation at End of 10 cm cable Original Pulse at LED

Preliminary SPES of LED

HF LED Pulser (next generation) - Reduced pulse width - Decreased rise time

HF PMT Papers

CMS Notes CMS IN 2002/026 CMS IN 2002/032

CMS Notes CMS IN 2002/030 CMS IN 2002/029

Manufacturer specIowa Tests Window Material Borosilicate glass PASSNA Eff. Pho.cath. dia mm, head-on PASSNA Quantum efficiency >15% nm PASSNA Photocathode lifetime >200 mC PASSNA Anode current vs position <+/-20% with 3 mm spot scan PASS Gain 10^4 to 10^5,10^5 at <0.75 x V ka(max) PASS Single pe resolution rms/mean if single pe peak 50% or better PASS Pulse linearity +/- 2% for photoelectrons (g=4X10^4) PASS Anode pulse rise-time <5ns PASS Transit time <25 ns preferred PASS Transit time spread <2 ns preferred PASS Anode pulse width <15 ns FWHM PASS Gain (1/2)-lifetime >1500 C PASSNA Gain recov. (2000pe pulse) within 10% of nominal (g=10^4) in 25 ns PASS Average current Ik <1 nA (g=10^4) PASS Average current Ia <10 microA (g=10^4) PASS Anode dark current <2 nA (g=10^4) PASS Stability <+/- 3% within any 48 hr. period PASSNA Envelope opaque and -HV conductive coating PASSNA