## E760 constants from 1991 run

#### BEAM

Diameter: **5 mm** (for 95% containment)

Peak luminosity achieved: **1.0 x 10^31 cm^-2 s^-1**

Lifetime: 50-90 hours depending on the energy
of the beam

Momentum spread: **< 2 x 10^-4**

Momentum spread for etac: **1.5 x 10^-3**

(source: J/psi and psi' Phys.Rev.D paper)

#### TARGET

Diameter: **6.3 mm** (for 95% containment)

Typical density: **3.5 x 10^13 atoms/cm^2 **

(source: J/psi and psi' Phys.Rev.D paper)

#### LUMINOSITY

Statistical error: **< 0.5%**

Systematic errors:

Counter area: **1.5%**

Differential cross section uncertainty: **2.5%**

(source: S.Trokenheim)

#### CCAL

Averaged energy resolution: sigma/E = **0.01 + 0.06/sqrt(E)**
E in GeV

Averaged theta resolution (sigma): **6 mrad**

Averaged phi resolution (sigma): **12 mrad**

(source: J.Fast's thesis study with psis)

#### FCAL

Energy resolution: sigma/E = **0.19/sqrt(E)**
E in GeV

Position resolution: Dx = Dy = **3 cm** (r.m.s.)

(source: A.Majewska's thesis)

#### TRACKING

Averaged theta resolution: **4 mrad** (r.m.s.)

Averaged phi resolution: **7 mrad ** (r.m.s.)

(source: chi1,chi2 Nucl.Phys. paper)

####
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