nuVeto

This package calculates the effect of a detector veto on the high-energy atmospheric neutrino flux via detection of muons that reach the detector. The result calculated is the passing-flux or passing-fraction of atmospheric neutrinos as a function of energy and zenith angle.

Getting started

It is recommended to work within a Python virtual environment.

python3 -m venv vdir
source vdir/bin/activate

Installing

pip install nuVeto

This will install numpy, scipy and MCEq.

As of v2.3.1 a suite of tests is also packaged. It uses pytest, which can be optionally installed and run as follows.

pip install nuVeto[testing]
pytest --pyargs nuVeto

Extras are pip install nuVeto[plotting, resources] which will install necessary packages for making plots and generating alternative detector response parameterizations (muon reaching probabilities).

Note that v2.0 and higher rely on the updated version of MCEq. For the legacy version that relies on MCEq_classic do git checkout v1.5 and see the README.

Usage

The simplest way to run is

from nuVeto.nuveto import passing
from nuVeto.utils import Units
import crflux.models as pm

enu = 1e5*Units.GeV
cos_theta = 0.5
pf = passing(enu, cos_theta, kind='conv nu_mu',
             pmodel=(pm.HillasGaisser2012, 'H3a'),
             hadr='SIBYLL2.3c', depth=1950*Units.m,
             density=('CORSIKA', ('SouthPole','December')))

where kind can be (conv|pr|_parent_) nu_(e|mu)(bar)

See examples/plots.py for more detailed examples.

Building muon detection probabilities

To calculate the passing fraction requires knowing the muon detection probability as a function of the overburden and energy of the muon at the surface. This is constructed from a convolution of the muon reaching probability and the detector response. The scripts for generating the necessary files are not packaged but provided in the resources/ directory, which can be obtained with a clone of this repository. They also require some extra dependencies, which can be installed with pip install nuVeto[resources].

The muon reaching probability is constructed from MMC simulations and is provided for propagation in ice in resources/mu/mmc/ice_(allm97|bb).pklz for two different cross section parameterizations. The detector response probability must be defined in resources/mu/pl.py as a function of the muon energy (at detector). Then, construct the overall muon detection probability.

cd resources/mu
./mu.py -o mymudet.pkl --plight pl_step_1000 mmc/ice_allm97.pklz

To use the newly generated file, pass the stem without file extension as a string to the prpl argument.

passing(enu, cos_theta, prpl='mymudet')`.

Contributers

Carlos Arguelles, Sergio Palomares-Ruiz, Austin Schneider, Logan Wille, Tianlu Yuan