The CLAS drift chamber system

Experimental Hall B at Jefferson Laboratory houses the CEBAF Large Acceptance Spectrometer, the magnetic field of which is produced by a superconducting toroid. The six coils of this toroid divide the detector azimuthally into six sectors, each of which contains three large multi-layer drift chambers for tracking charged particles produced from a fixed target on the toroidal axis. Within the 18 drift chambers are a total of 35,148 individually instrumented hexagonal drift cells. The novel geometry of these chambers provides for good tracking resolution and efficiency, along with large acceptance. The design and construction challenges posed by these large-scale detectors are described, and detailed results are presented from in-beam measurements.

29.40.Cs
29.40.Gx
CLAS
Drift chambers
Tracking system
tracks
drift chamber: gas
argon: organic compounds
efficiency
Newport News CEBAF Linac

References(25)

Figures(0)

[1]

Report

Hall B. Conceptual Design

[2]

Choosing the correct combination of sense, field, and guard wire voltage CLAS-Note 92-005

M.D. Mestayer

[3]

Wire chamber aging

John A. Kadyk
(
- LBL, Berkeley
)

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•
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[4]

Minimizing cathode emission in drift chambers, CLAS-Note 92-016

S.B. Christo
,
M.D. Mestayer

[5]

Outgassing data for selecting spacecraft materials, NASA Internal Report RP-1124 Rev. 3

W. Campbell
,
J. Scialdone

[6]

Considerations for crimping the CLAS drift chamber wires CLAS-Note 89-021

S.B. Christo

[7]

The region one drift chamber for the CLAS spectrometer

D.S. Carman
(
- Carnegie Mellon U.
)
,
S.A. Dytman
(
- Pittsburgh U.
)
,
R. Magahiz
(
- Carnegie Mellon U.
)
,
M.D. Mestayer
(
- Jefferson Lab
)
,
R.A. Miskimen
(
- Massachusetts U., Amherst
)

et al.

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•
DOI:
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[8]

The region 1 drift chamber endplates: procurement history and inspection results, CLAS-Note 94-018

R.A. Schumacher
,
R. Magahiz

[9]

Master's Thesis, University of Pittsburgh

S.J. Bianculli

[10]

Issues in stringing the large acceptance spectrometer region 1 drift chamber, CLAS-Note 96-019

R.A. Thompson

[11]

Design and performance of the large HERMES drift chambers

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•
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[12]

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[13]

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•
DOI:
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[14]

Prototype studies and design considerations for the CLAS region 2 drift chambers

L.M. Qin
(
- Old Dominion U.
)
,
B.A. Raue
(
- Old Dominion U.
)
,
G.E. Dodge
(
- Old Dominion U.
)
,
Charles Earl Hyde
(
- Old Dominion U.
)
,
A. Klein
(
- Old Dominion U.
)

et al.

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•
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[15]

Investigations into wire sag in the CLAS drift chambers, CLAS-Notes 89-016, 89-017

M. Chew

[16]

A computer-controlled tension monitoring system for drift chamber wires

S.A. Roth
(
- Carnegie Mellon U.
)
,
R.A. Schumacher
(
- Carnegie Mellon U.
)

- Nucl.Instrum.Meth.A 369 (1996) 215-221
•
DOI:
- 10.1016/0168-9002(95)00783-0

[17]

Region one drift chamber analysis of survey data, CLAS-Note 98-001

R.A. Schumacher

[18]

A preamp for the CLAS DC, CLAS-Note 92-003

F.J. Barbosa

[19]

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M.F. Vineyard
,
T.J. Carroll
,
M.N. Lack

[20]

GARFIELD has been developed at the University of Mainz by and revised by M. Guckes and K. Peters See HELIOS-note 154

R. Veenhof

[21]

CLAS region I prototype detector, CLAS-Note 96-022

D.S. Carman

[22]

Construction update and drift velocity calibration for the CLAS drift chamber system

et al.

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•
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[23]

M.D. Mestayer

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[24]

Performance of a region II drift chamber prototype and region II drift chamber tracking, CLAS-Note 96-018

L.M. Qin

[25]

Hall B test run: drift chamber studies, CLAS-Note 97-001

D.S. Carman