Skip to main content

Python project to work with 4-vectors and Lorentz boots in high energy physics.

Project description

pylorentz

https://gitlab.sauerburger.com/frank/pylorentz/badges/master/pipeline.svg https://gitlab.sauerburger.com/frank/pylorentz/badges/master/coverage.svg https://gitlab.sauerburger.com/frank/pylorentz/-/jobs/artifacts/master/raw/pylint.svg?job=pylint https://gitlab.sauerburger.com/frank/pylorentz/-/jobs/artifacts/master/raw/license.svg?job=badges https://gitlab.sauerburger.com/frank/pylorentz/-/jobs/artifacts/master/raw/pypi.svg?job=pypi https://readthedocs.org/projects/pylorentz/badge/?version=latest&style=flat

The python package pylorentz provides classes to facilitate computations with 4-vectors in high-energy physics.

Quickstart

Install the package using pip

$ pip install git+https://gitlab.sauerburger.com/frank/pylorentz.git

or

$ pip install pylorentz

Properties

The package defines three types of 4-vectors: general purpose vectors, 4-positions and 4-momenta. The working horse of the package are 4-momenta.

>>> from pylorentz import Momentum4
>>> muon = Momentum4.m_eta_phi_pt(0.1057, 4.5, 1.5, 35)
>>> muon.eta
4.5
>>> muon.phi
1.5
>>> muon.p_t
35.0
>>> "%.2f" % muon.p
'1575.49'
>>> "%.2f" % muon.e
'1575.49'

Vectorized Properties

Since version 0.2.0, it is possible to pass numpy arrays to the constructors and operate on multiple vectors at a time.

>>> from pylorentz import Momentum4
>>> import numpy as np
>>> masses = np.array([0.0005, 0.1057, 1.7769])
>>> etas = np.array([1, 2, 3])
>>> phis = np.array([0, 0, 0])
>>> pts = np.array([10, 10, 10])
>>> muon = Momentum4.m_eta_phi_pt(masses, etas, phis, pts)
>>> ["%.2f" % m for m in muon.e]
['15.43', '37.62', '100.69']

Arithmetics

4-vectors support a variety of arithmetic operations. The most important one is the addition of two vectors.

>>> from pylorentz import Momentum4
>>> tau_1 = Momentum4.m_eta_phi_pt(1.777, 4.5, 1.5, 35)
>>> tau_2 = Momentum4.m_eta_phi_pt(1.777, -4.5, 1.5, 35)

We can add the momenta of the two tau leptons and access the properties of the parent particle.

>>> parent = tau_1 + tau_2
>>> "%.2f" % parent.m
'3150.21'
>>> "%.2f" % parent.eta
'0.00'
>>> "%.2f" % parent.phi
'1.50'

Lorentz Boosts

The package also provides methods to perform Lorentz boosts. For example, consider the decay of a Higgs boson to a pair of tau leptons in the rest frame of the Higgs boson. The tau leptons are back-to-back in the y-z-plane.

>>> import math
>>> from pylorentz import Momentum4
>>> m = 125.0
>>> tau_1 = Momentum4.e_m_eta_phi(m / 2, 1.777, 1.5, math.pi / 2)
>>> tau_2 = Momentum4.e_m_eta_phi(m / 2, 1.777, -1.5, -math.pi / 2)

Now let’s assume the Higgs boson itself is not at rest. We can define its momentum and then boost the two tau leptons.

>>> higgs = Momentum4.m_eta_phi_pt(m, 2, 0, 250)
>>> tau_1.boost_particle(higgs)
Momentum4(884.599, 220.498, 26.5578, 856.264)
>>> tau_2.boost_particle(higgs)
Momentum4(64.2195, 29.5021, -26.5578, 50.451)

Project details


Download files

Download the file for your platform. If you're not sure which to choose, learn more about installing packages.

Files for pylorentz, version 0.3.3
Filename, size File type Python version Upload date Hashes
Filename, size pylorentz-0.3.3.tar.gz (12.3 kB) File type Source Python version None Upload date Hashes View

Supported by

Pingdom Pingdom Monitoring Google Google Object Storage and Download Analytics Sentry Sentry Error logging AWS AWS Cloud computing DataDog DataDog Monitoring Fastly Fastly CDN DigiCert DigiCert EV certificate StatusPage StatusPage Status page