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| author | Stan Seibert <stan@mtrr.org> | 2011-10-25 17:10:52 -0400 |
|---|---|---|
| committer | tlatorre <tlatorre@uchicago.edu> | 2021-05-09 08:42:38 -0700 |
| commit | 35de3b77163a779fbe32abc255a452a943836ad9 (patch) | |
| tree | 444c5f434738b82298c6869c176b412d65d245a1 | |
| parent | 70a2bdfe04e69303f8ee0d8fe8fd56e2006ccbe2 (diff) | |
| download | chroma-35de3b77163a779fbe32abc255a452a943836ad9.tar.gz chroma-35de3b77163a779fbe32abc255a452a943836ad9.tar.bz2 chroma-35de3b77163a779fbe32abc255a452a943836ad9.zip | |
Add optional argument to pi0 gun to pick direction of one gamma in rest frame.
| -rw-r--r-- | chroma/generator/vertex.py | 15 |
1 files changed, 10 insertions, 5 deletions
diff --git a/chroma/generator/vertex.py b/chroma/generator/vertex.py index e138e80..2a3bedf 100644 --- a/chroma/generator/vertex.py +++ b/chroma/generator/vertex.py @@ -48,15 +48,20 @@ def particle_gun(particle_name_iter, pos_iter, dir_iter, ke_iter, ev_vertex = event.Event(i, vertex, [vertex]) yield ev_vertex -def pi0_gun(pos_iter, dir_iter, ke_iter, t0_iter=constant(0.0), start_id=0): - for i, pos, dir, ke, t0 in izip(count(start_id), pos_iter, dir_iter, ke_iter, t0_iter): +def pi0_gun(pos_iter, dir_iter, ke_iter, t0_iter=constant(0.0), start_id=0, gamma1_dir_iter=None): + + if gamma1_dir_iter is None: + gamma1_dir_iter = isotropic() + + for i, pos, dir, ke, t0, gamma1_dir in izip(count(start_id), pos_iter, dir_iter, ke_iter, t0_iter, gamma1_dir_iter): dir /= np.linalg.norm(dir) primary_vertex = event.Vertex('pi0', pos, dir, ke, t0=t0) - cos_theta_rest = np.random.random_sample() * 2 - 1 - theta_rest = np.arccos(cos_theta_rest) - phi_rest = np.random.random_sample() * 2 * np.pi + # In rest frame + theta_rest = np.arccos(gamma1_dir[2]) + phi_rest = np.arctan2(gamma1_dir[0], gamma1_dir[1]) + # In lab frame (gamma1_e, gamma1_dir), (gamma2_e, gamma2_dir) = \ pi0_decay(ke+134.9766, dir, theta_rest, phi_rest) |