from typing import Tuple
import numpy as np
from astropy.units import Quantity, Unit
from cosmoglobe.data import DATA_DIR
from cosmoglobe.sky._base_components import DiffuseComponent
from cosmoglobe.sky._units import cmb_equivalencies
from cosmoglobe.sky.components._labels import SkyComponentLabel
SPDUST2_FILE = DATA_DIR / "spdust2_cnm.dat"
SPDUST2_FREQS, SPDUST2_AMPS = np.loadtxt(SPDUST2_FILE, unpack=True)
SPDUST2_FREQS *= Unit("GHz")
SPDUST2_AMPS *= Unit("Jy/sr")
SPDUST2_TEMPLATE = (SPDUST2_FREQS, SPDUST2_AMPS)
[docs]class SpinningDust(DiffuseComponent):
r"""Class representing the AME component in the Cosmoglobe Sky Model.
Notes
-----
The spinning dust emission is defined using the convention in
`BeyondPlanck (2020), Section 3.3.4
<https://arxiv.org/pdf/2011.05609.pdf>`_;
.. math::
\boldsymbol{s}_{\mathrm{RJ}}^{\mathrm{sd}}(\nu) \propto
\nu^{-2} \boldsymbol{s}_{0}^{\mathrm{sd}}\left(\nu \cdot
\frac{30.0\; \mathrm{GHz}}{\nu_{p}}\right)
where :math:`\nu` is the frequency for which we are simulating the
sky emission, :math:`\boldsymbol{s}_0^{\mathrm{sd}}` is the `spdust2`
template, and :math:`\nu_p` the peak frequency.
"""
label = SkyComponentLabel.AME
freq_range = (0 * Unit("Hz"), 500 * Unit("GHz"))
SPINNING_DUST_TEMPLATE: Tuple[Quantity, Quantity] = SPDUST2_TEMPLATE
[docs] def get_freq_scaling(self, freqs: Quantity, freq_peak: Quantity) -> Quantity:
"""See base class."""
spdust2_freqs = SPDUST2_TEMPLATE[0]
# We set the spdust2 template amplitudes to the component amplitude units.
spdust2_amps = SPDUST2_TEMPLATE[1].to(
self.amp.unit, equivalencies=cmb_equivalencies(spdust2_freqs)
)
peak_scale = 30 * Unit("GHz") / freq_peak
interp = np.interp(
(freqs * peak_scale).si.value,
spdust2_freqs.si.value,
spdust2_amps.decompose().value,
left=0.0,
right=0.0,
)
interp_ref = np.interp(
(self.freq_ref * peak_scale).si.value,
spdust2_freqs.si.value,
spdust2_amps.decompose().value,
)
scaling = interp / interp_ref
return Quantity(scaling)