2-body collision

Beam particle 1 on fixed target 2. Algebraic θ* from tan θ_lab; illegal angles throw. Masses & KE in MeV (natural).

√s (MeV)
1925.90
Available KE in CM (MeV)
49.3511
β (v/c) of CM
0.224930
γ_CM
1.02630
E₁* (MeV)
962.948
E₂* (MeV)
962.948
θ_lab max (kinematic)
90.00°
ρ = β_CM / β₁*
1.00000
Kinematic cone
ρ=1 · θ_lab ≤ 90°
θ* (unique)
61.30°
E₁ lab (MeV)
1012.29
E₂ lab (MeV)
964.258

Gold check: equal mass ⇒ θ_lab^max = 90° (independent of beam KE).

Lorentz factors

xct
γ
1.25000
γβ
0.750000
β (v/c)
0.600000
Time dilation γ
1.25000
Length contraction 1/γ
0.800000
Rest energy (MeV)
0.511000
Total energy (MeV)
0.638750
Kinetic energy (MeV)
0.127750

Two-body decay

Parent → daughter 1 + daughter 2. θ* is the rest-frame emission angle of daughter 1 relative to the boost axis.

Q-value (MeV)
33.4010
E₁* (MeV)
109.777
E₂* (MeV)
29.7931
p* (MeV/c)
29.7887
β (v/c) parent
0.676714
γ parent
1.35824
E₁ lab (MeV)
170.079
E₂ lab (MeV)
19.4919
θ₁ lab
8.260°
θ₂ lab
-100.7°

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Parameter grids for collisions, decays, Compton, and Bosch–Hale ⟨σv⟩ — included with Pro.

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Course pack

Ten homework-shaped initial conditions with gold checks. Titles are free; JSON + answer keys are Pro.

  1. pp elastic at 100 MeV, 30°
  2. Equal-mass gold check at 90°
  3. Kinematic cone (m1 > m2)
  4. π⁰ → γγ at rest vs in flight
  5. γ at β = 0.6
  6. Compton at 90°
  7. Fresnel air → glass, normal incidence
  8. Product error σ(xy)
  9. DT reactivity at 10 keV
  10. Kepler lab: eccentricity overlay
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