def test_helix(self):
cyl1 = SurfaceCylinder('cyl1', 1., 2.)
cyl2 = SurfaceCylinder('cyl2', 2., 1.)
field = 3.8
particle = Particle(LorentzVector(2., 0, 1, 5), Point(0., 0., 0.), -1)
debug_info = helix.propagate_one(particle, cyl1, field)
particle = Particle(LorentzVector(0., 2, 1, 5), Point(0., 0., 0.), -1)
debug_info = helix.propagate_one(particle, cyl1, field)
def test_straightline(self):
origin = Point(0, 0, 0)
cyl1 = SurfaceCylinder('cyl1', 1, 2)
cyl2 = SurfaceCylinder('cyl2', 2, 1)
particle = Particle(LorentzVector(1, 0, 1, 2.), origin, 0)
straight_line.propagate_one(particle, cyl1)
straight_line.propagate_one(particle, cyl2)
self.assertEqual(len(particle.points), 3)
# test extrapolation to barrel
self.assertAlmostEqual(particle.points['cyl1'].Perp(), 1.)
self.assertAlmostEqual(particle.points['cyl1'].Z(), 1.)
# test extrapolation to endcap
self.assertAlmostEqual(particle.points['cyl2'].Z(), 1.)
# testing extrapolation to -z
particle = Particle(LorentzVector(1, 0, -1, 2.), origin, 0)
# import pdb; pdb.set_trace()
straight_line.propagate_one(particle, cyl1)
straight_line.propagate_one(particle, cyl2)
self.assertEqual(len(particle.points), 3)
self.assertAlmostEqual(particle.points['cyl1'].Perp(), 1.)
# test extrapolation to endcap
self.assertAlmostEqual(particle.points['cyl1'].Z(), -1.)
self.assertAlmostEqual(particle.points['cyl2'].Z(), -1.)
# extrapolating from a vertex close to +endcap
particle = Particle(LorentzVector(1, 0, 1, 2.), Point(0, 0, 1.5), 0)
straight_line.propagate_one(particle, cyl1)
self.assertAlmostEqual(particle.points['cyl1'].Perp(), 0.5)
# extrapolating from a vertex close to -endcap
particle = Particle(LorentzVector(1, 0, -1, 2.), Point(0, 0, -1.5), 0)
straight_line.propagate_one(particle, cyl1)
self.assertAlmostEqual(particle.points['cyl1'].Perp(), 0.5)
# extrapolating from a non-zero radius
particle = Particle(LorentzVector(0, 0.5, 1, 2.), Point(0, 0.5, 0), 0)
straight_line.propagate_one(particle, cyl1)
self.assertAlmostEqual(particle.points['cyl1'].Perp(), 1.)
self.assertAlmostEqual(particle.points['cyl1'].Z(), 1.)
# extrapolating from a z outside the cylinder
particle = Particle(LorentzVector(0, 0, -1, 2.), Point(0, 0, 2.5), 0)
straight_line.propagate_one(particle, cyl1)
self.assertFalse('cyl1' in particle.points)
# extrapolating from a z outside the cylinder, negative
particle = Particle(LorentzVector(0, 0, -1, 2.), Point(0, 0, -2.5), 0)
straight_line.propagate_one(particle, cyl1)
self.assertFalse('cyl1' in particle.points)
# extrapolating from a rho outside the cylinder
particle = Particle(LorentzVector(0, 0, -1, 2.), Point(0, 1.1, 0), 0)
straight_line.propagate_one(particle, cyl1)
self.assertFalse('cyl1' in particle.points)
def monojet(pdgids, theta, phi, pstar, jetenergy, vertex=None):
particles = []
if vertex is None:
vertex = TVector3(0., 0., 0.)
jetp4star = TLorentzVector()
for pdgid in pdgids[:-1]:
mass, charge = particle_data[pdgid]
phistar = random.uniform(-math.pi, math.pi)
thetastar = random.uniform(-math.pi, math.pi)
sint = math.sin(thetastar)
cost = math.cos(thetastar)
sinp = math.sin(phistar)
cosp = math.cos(phistar)
pz = pstar * cost
px = pstar * sint * cosp
py = pstar * sint * sinp
p4 = TLorentzVector()
p4.SetXYZM(px, py, pz, mass)
jetp4star += p4
particles.append(Particle(p4, vertex, charge, pdgid))
pdgid = pdgids[-1]
mass, charge = particle_data[pdgid]
p4 = TLorentzVector()
p4.SetVectM(-jetp4star.Vect(), mass)
particles.append(Particle(p4, vertex, charge, pdgid))
jetp4star += p4
#boosting to lab
gamma = jetenergy / jetp4star.M()
beta = math.sqrt(1 - 1 / gamma**2)
boostvec = TVector3(
math.sin(theta) * math.cos(phi),
math.sin(theta) * math.sin(phi), math.cos(theta))
boostvec *= beta
boosted_particles = []
jetp4 = LorentzVector()
for ptc in particles:
bp4 = LorentzVector(ptc.p4())
bp4.Boost(boostvec)
jetp4 += bp4
boosted_particles.append(
Particle(bp4, ptc.vertex, ptc.q(), ptc.pdgid()))
# print jetp4.M(), jetp4.E()
return boosted_particles
def particle(pdgid, theta, phi, energy, vertex=None):
if vertex is None:
vertex = Point(0, 0, 0)
mass, charge = particle_data[pdgid]
momentum = math.sqrt(energy**2 - mass**2)
costheta = math.cos(theta)
sintheta = math.sin(theta)
cosphi = math.cos(phi)
sinphi = math.sin(phi)
p4 = LorentzVector(momentum * sintheta * cosphi,
momentum * sintheta * sinphi, momentum * costheta,
energy)
return Particle(p4, vertex, charge, pdgid)
def particles(nptcs, pdgid, thetamin, thetamax, emin, emax, vertex=None):
ngenerated = 0
mass, charge = particle_data[pdgid]
while ngenerated < nptcs:
theta = random.uniform(thetamin, thetamax)
phi = random.uniform(-math.pi, math.pi)
energy = random.uniform(emin, emax)
if vertex is None:
vertex = Point(0, 0, 0)
momentum = math.sqrt(energy**2 - mass**2)
costheta = math.cos(theta)
sintheta = math.sin(theta)
cosphi = math.cos(phi)
sinphi = math.sin(phi)
p4 = LorentzVector(momentum * sintheta * cosphi,
momentum * sintheta * sinphi, momentum * costheta,
energy)
ngenerated += 1
yield Particle(p4, vertex, charge, pdgid)