# Licensed under a 3-clause BSD style license - see LICENSE.rst
"""Dark matter spectra."""
from __future__ import absolute_import, division, print_function, unicode_literals
import numpy as np
from astropy.units import Quantity
from astropy.table import Table
from astropy.utils import lazyproperty
from ...utils.scripts import make_path
from ...spectrum.models import TableModel
__all__ = ["PrimaryFlux"]
[docs]class PrimaryFlux(object):
"""DM-annihilation gamma-ray spectra.
Based on the precomputed models by `Cirelli et al.
<http://www.marcocirelli.net/PPPC4DMID.html>`_. All available
annihilation channels can be found there. The dark matter mass will be set
to the nearest available value. The spectra will be available as
`~gammapy.spectrum.models.TableModel` for a chosen dark matter mass and
annihilation channel.
References
----------
* `2011JCAP...03..051 <http://adsabs.harvard.edu/abs/2011JCAP...03..051>`_
"""
channel_registry = {
"eL": "eL",
"eR": "eR",
"e": "e",
"muL": "\\[Mu]L",
"muR": "\\[Mu]R",
"mu": "\\[Mu]",
"tauL": "\\[Tau]L",
"tauR": "\\[Tau]R",
"tau": "\\[Tau]",
"q": "q",
"c": "c",
"b": "b",
"t": "t",
"WL": "WL",
"WT": "WT",
"W": "W",
"ZL": "ZL",
"ZT": "ZT",
"Z": "Z",
"g": "g",
"gamma": "\\[Gamma]",
"h": "h",
"nu_e": "\\[Nu]e",
"nu_mu": "\\[Nu]\\[Mu]",
"nu_tau": "\\[Nu]\\[Tau]",
"V->e": "V->e",
"V->mu": "V->\\[Mu]",
"V->tau": "V->\\[Tau]",
}
def __init__(self, mDM, channel):
self.mDM = mDM
self.channel = channel
@lazyproperty
def table(self):
"""Lookup table (`~astropy.table.Table`)."""
filename = "$GAMMAPY_DATA/dark_matter_spectra/AtProduction_gammas.dat"
return Table.read(
str(make_path(filename)),
format="ascii.fast_basic",
guess=False,
delimiter=" ",
)
@property
def mDM(self):
"""Dark matter mass."""
return self._mDM
@mDM.setter
def mDM(self, mDM):
mDM_vals = self.table["mDM"].data
mDM_ = Quantity(mDM).to("GeV").value
interp_idx = np.argmin(np.abs(mDM_vals - mDM_))
self._mDM = Quantity(mDM_vals[interp_idx], "GeV")
@property
def allowed_channels(self):
"""List of allowed annihilation channels."""
return list(self.channel_registry.keys())
@property
def channel(self):
"""Annihilation channel (str)."""
return self._channel
@channel.setter
def channel(self, channel):
if channel not in self.allowed_channels:
msg = "Invalid channel {}\n"
msg += "Available: {}\n"
raise ValueError(msg.format(channel, self.allowed_channels))
else:
self._channel = channel
@property
def table_model(self):
"""Spectrum as `~gammapy.spectrum.models.TableModel`."""
subtable = self.table[self.table["mDM"] == self.mDM.value]
energies = (10 ** subtable["Log[10,x]"]) * self.mDM
channel_name = self.channel_registry[self.channel]
dN_dlogx = subtable[channel_name]
dN_dE = dN_dlogx / (energies * np.log(10))
return TableModel(energy=energies, values=dN_dE, values_scale="lin")