High sensitivity external modulator data link for high energy particle detector diagnostics

Conference · Fri May 01 00:00:00 EDT 1992

OSTI ID:10182812

McCammon, K; Lowry, M; Wuest, C; McConaghy, C ^[1]; Chang, Yuanhann; Wyslouch, B; Becker, U ^[2]; Parker, P ^[3]

---

1. Lawrence Livermore National Lab., CA (United States)
2. Massachusetts Inst. of Tech., Cambridge, MA (United States). Lab. for Nuclear Science
3. EG and G Energy Measurements, Inc., Pleasanton, CA (United States). Amador Valley Operations

An analog fiber-optic data link has been demonstrated for direct charge readout of wire chambers used in high energy particle detectors. The fiber link consists of a Nd:YAG laser carrier, a Mach-Zehnder external modulator, and a low-noise optical receiver. A charge pulse developed on a sensing wire flows directly into the electro-optic modulator with no preamplification. The substitution of passive modulators and fiber cable for active electronics and copper wire near large collider detectors has clear advantages with regard to radiation damage susceptibility, EMI immunity, physical size, and power consumption. Also, the modulator performance was unaffected for an applied one Tesla magnetic field. Reduction of noise contributions from the laser carrier and optical receiver and exploitation of the ``effective optical gain`` properties of external modulators resulted in shot-noise-limited link sensitivity. Modulators were, packaged with large termination resistors enabling increased charge sensitivity with an increased system risetime tradeoff. Energy resolution of the fiber HA was comparable to preamps condidonal on large terminations and subsequent slow readout For shorter risetimes required in timing diagnostics, small terminations resulted in sensitivity 6.8 times inferior to preamps. Several potential improvements in sensitivity are discussed.

• Research Organization: Lawrence Livermore National Lab., CA (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 10182812
• Report Number(s): UCRL-JC-111225; CONF-9205210-3; ON: DE92041084
• Resource Relation: Conference: 2. annual conference on electronics for future colliders,Chestnut Ridge, NY (United States),19-21 May 1992; Other Information: PBD: May 1992
• Country of Publication: United States
• Language: English

Related Subjects

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
MULTIWIRE PROPORTIONAL CHAMBERS
DATA TRANSMISSION SYSTEMS
FIBER OPTICS
SENSITIVITY
HIGH ENERGY PHYSICS
CONNECTORS
RECORDING SYSTEMS
ELECTRO-OPTICAL EFFECTS
MAGNETIC FIELDS
PHYSICAL RADIATION EFFECTS
440104
440200
HIGH ENERGY PHYSICS INSTRUMENTATION
RADIATION EFFECTS ON INSTRUMENT COMPONENTS
INSTRUMENTS
OR ELECTRONIC SYSTEMS