From 084dfd08b714faefaea77cb7dc04d2e93dc04b1d Mon Sep 17 00:00:00 2001
From: Stan Seibert <stan@mtrr.org>
Date: Fri, 16 Sep 2011 14:27:46 -0400
Subject: File reorganization to move toward standard python package layout

---
 pi0.py | 69 ------------------------------------------------------------------
 1 file changed, 69 deletions(-)
 delete mode 100644 pi0.py

(limited to 'pi0.py')

diff --git a/pi0.py b/pi0.py
deleted file mode 100644
index 91e8097..0000000
--- a/pi0.py
+++ /dev/null
@@ -1,69 +0,0 @@
-import numpy as np
-
-_kg_per_MeV = 1.782661758e-36/1e-6
-_pi0_mass = 134.9766*_kg_per_MeV
-
-def rocket_to_lab(energy, momentum, v):
-    """
-    Return the energy and momentum of a particle in the lab frame from its
-    energy and momentum in a rocket frame traveling at a velocity `v` with
-    respect to the lab frame.
-
-    Args:
-        - energy: float, kg
-            The energy of the particle in the rocket frame.
-        - momentum: array, kg
-            The momentum of the particle in the rocket frame.
-        - v: array, units of c
-            The velocity of the rocket frame as seen in the lab frame.
-    """
-    e0 = float(energy)
-    p0 = np.asarray(momentum, float)
-    v = np.asarray(v, float)
-
-    assert e0**2 - p0.dot(p0) >= -1.0e-70
-
-    g = 1.0/np.sqrt(1.0-v.dot(v))
-
-    x = np.dot(p0, v)/np.linalg.norm(v)
-    p = p0 + ((g-1.0)*x + g*np.linalg.norm(v)*e0)*v/np.linalg.norm(v)
-    e = np.sqrt(e0**2 - p0.dot(p0) + p.dot(p))
-
-    return e, p
-
-def pi0_decay(energy, direction, theta, phi):
-    """
-    Return the energy and directions for two photons produced from a pi0
-    decay in the lab frame given that one of the photons decayed at polar
-    angles `theta` and `phi` in the pi0 rest frame.
-
-    Args:
-        - energy: float, MeV
-            The total energy of the pi0.
-        - direction: array
-            The direction of the pi0's velocity in the lab frame.
-
-    Returns:
-        - e1: float, MeV
-            The energy of the first photon in the lab frame.
-        - v1: array,
-            The direction of the first photon in the lab frame.
-        - e2: float, MeV
-            The energy of the second photon in the lab frame.
-        - v2: array,
-            The direction of the second photon in the lab frame.
-    """
-    direction = np.asarray(direction)/np.linalg.norm(direction)
-    pi0_e = float(energy)*_kg_per_MeV
-    pi0_p = np.sqrt(pi0_e**2-_pi0_mass**2)*direction
-    pi0_v = pi0_p/pi0_e
-
-    photon_e0 = _pi0_mass/2.0
-    photon_p0 = photon_e0*np.array([np.cos(theta)*np.sin(phi), np.sin(theta)*np.sin(phi), np.cos(phi)])
-
-    e1, p1 = rocket_to_lab(photon_e0, photon_p0, pi0_v)
-    v1 = p1/np.linalg.norm(p1)
-    e2, p2 = rocket_to_lab(photon_e0, -photon_p0, pi0_v)
-    v2 = p2/np.linalg.norm(p2)
-
-    return (e1/_kg_per_MeV, v1), (e2/_kg_per_MeV, v2)
-- 
cgit