FToF Status Report CLAS Collaboration Meeting1 Test Results, Ongoing Work, Still To-Do, and More … FToF Progress Report CLAS Collaboration Meeting June

FToF Status Report CLAS Collaboration Meeting 1

Test Results, Ongoing Work, Still To-Do, and More …

FToF Progress Report

CLAS Collaboration Meeting June 2009

Jefferson Lab, Newport News, VA

Ralf W. Gothe

University of South Carolina


Forward Time-of-Flight UpgradeJLab Designer

FTOF Panel 1aFTOF Panel 1b

Solenoid 5T

CTOF

SVT

Central Detector

DC R1, R2, R3

LTCC

PCAL

EC

HTCC

TORUS

Forward Detector



2

1



2

1a&b

Panel 1b



Panel 1b



Panel 1b


Particle p-Θ Distributions in DIS Kinematics

45o

45o

45o


Design Requirements

Proton-Pion separation up to 5.3 GeV/c

Kaon-Pion separation up to 2.6 GeV/c

To achieve

and

an improved timing resolution of ~ 80 ps is needed

Proton-Kaon separation up to 4.5 GeV/c


The Present Time-of-Flight System

15 cm width (forward angle)22 cm width (large angle)

0 : ElectronicsHas to be optimized!

1 : Scintillator and PMTHas to be optimized!

p : Path-Length VariationHas to be optimized!

Npe: # of photoelectronsHas to be tripled!


Design Requirements

better than ~ 150 ps for the current FTOF panel

better than ~ 95 ps for the new FTOF panel

With a resolution for the longest scintillators of

and

a combined timing resolution of ~ 80 ps can be accomplished

FToF Status Report CLAS Collaboration Meeting

Time-of-Flight Test Results


TDC and Electronics Resolution

The contribution fromelectronics includescontributions from theTDC, the NIM modules,cables, etc.

TDC resolution isdetermined with afixed cable delay.

tdc=30.5 ps

electronics=57.2 ps


Position Method

The 5mm scintillator allows paths such as those labeled A and B. Cut on ADC values to increase the ratio of B to A. Correct for time-walk. Cut on top/bottom time of flight to further reduce non-vertical paths. Correct for time-walk again.


Position Method ADC Cuts


Resolution After ADC Cuts

262 ps206 ps240 ps153 ps

TL TDC Values TR TDC Values BL TDC Values BR TDC Values

TL TDC vs ADC TR TDC vs ADC BL TDC vs ADC BR TDC vs ADC

ADC

TD

C

Top TDC Difference Top TDC Sum Btm TDC Difference Btm TDC Sum


Time-Walk Parameterization


Resolution after TW Correction

153 ps 156 ps 175 ps 173 ps



ADC

TD

C



Resolution after Vertical Cut

157 ps170 ps150 ps150 ps



ADC

TD

C



Time-Walk Parameterization II


Final Resolution for the Position Method

157 ps162 ps147 ps147 ps



ADC

TD

C



Three-Bar Method

Three bar method for prototype testing Modified to include two identical reference bars and an

exchangeable middle bar to quickly test scintillators of different lengths.

Three bar method with identical bars Need method to verify reference bar resolutions.


Bottom

Three-Bar Method Panel 1a Counter

Top

Raw Resolution

261 ps

counter= √2/3 ∗

TDC Differences

213*15*5 cm3


ADC and Center Cut Resolution

Center cut +ADC cuts

Top

Middle

Bottom193 ps

counter= √2/3 ∗




Final Resolution Panel 1a Counter

122 ps

counter= √2/3 ∗

213*15*5 cm3


186 ps

TDC Differences Raw Resolution

50*5*5 cm3

Three-Bar Method Panel 1b Counter

counter= √2/3 ∗


ADC and Center Cut Resolution

Center cut +ADC cuts

134 ps

counter= √2/3 ∗




71.2 ps

Final Resolution Panel 1b Counter50*5*5 cm3

counter= √2/3 ∗

CLAS6 ToF resolutions for 400/50/400*5*5 cm3 counter= 118 psCLAS6 ToF resolutions divided by √3 counter= 71 ps


Final Resolution Panel 1a Counter

122 ps

counter= √2/3 ∗

213*15*5 cm3

Extrapolated ToF resolution for 213*15*5 cm3 counter= 136 ps

Published ToF resolution for 213*15*5 cm3 counter= 118 ps


Design Requirements

better than ~ 150 ps for the current FTOF panel

better than ~ 95 ps for the new FTOF panel

extraploated ~87 ps

With a resolution for the longest scintillators of

and

a combined timing resolution of ~ 80 ps can be accomplished


Action Items

Three Identical Bar Reference 8/2009 Detector Calibration System Design 9/2009 FastMC: Panel 1b/1a or 1a/1b 9/2009 FastMC: Small Polar Angle Acceptance 9/2009 Scintillator Pair Mockup 9/2009

accomplished by


Key Milestones for PED and R&D

PMT and Scintillator Acquisition 9/2005 Assembly Hall Acquisition 8/2005 Infrastructure for Prototype Assembly 8/2006 Implementing Tests Procedures 8/2007 VME DAQ and LabView Run Control 8/2008 C++/ROOT Data Analysis 5/2009 Optimizing Detectors and Electronics 8/2009 Prototype Detector Beam Tests 3/2010 Final Detector Design 3/2010

accomplished by


Key Milestones for Construction

Ordering All Detector Components 9/2009 5/2010 Testing All Detector Components 9/2009 9/2010 Staggered Assembly of ToF Counters1/2010 1/2011 Testing Calibration System 9/2009 9/2010 ToF Counter Frame 1/2010 1/2011 Mounting and Cabling 1/2011 7/2011 Readout and Final Testing 2/2011 9/2011

Start Finish


Assigned USC Manpower in 2009 Faculty

R.W. Gothe (PI) S. Strauch D. Tedeschi

Post Doc (K. Park)

Graduate Students E. Phelps L. Graham (MS) H. Lu R. Steinman (MS) Y. Tian D. Xue

Undergraduate Students J. Giambernadino


Acquisitions by 2009

Electronics: NIM (LED, CFD), VME (TDCs), HV (CAEN), Readout (LabView)

Oscilloscopes: DPO 7254 (fast), 1 analog and 2 digital (slow)

PMTs: 2*9214 (ET), 2*R9779 (Hamamatsu),

2*XP2020, 2*XP2020UR, 2*XP20Y0, 2*XP20D0 (Photonis)

Voltage Deviders: 2*C638A (ET), 2*R9779 (Hamamatsu),

2*VD124KT, 2*VD127KT, 2*XP20Y0, 2*XP20D0 (Photonis)

Scintillators: EJ 204 (50, 100, 250 cm), EJ 200 (50, 100, 250, 400 cm) (ELJEN), BC 404 (20, 50 cm), BC 408 (50, 150, 400 cm) (Saint-Gobain)

Light Guides: 2*BC 802 (UV blind), 2*BC 800 (Saint-Gobain)

Wrapping: Tedlar Film, Aluminized Mylar Film, Tape, -Shielding

Others: 2*CLAS ToF Counters, Detector Lab, Assembly Hall, Infrastructure

Documents

FToF Status Report CLAS Collaboration Meeting1 Test Results, Ongoing Work, Still To-Do, and More … FToF Progress Report CLAS Collaboration Meeting June