diff options
| -rw-r--r-- | fg21sim/extragalactic/clusters/halo.py | 48 |
1 files changed, 48 insertions, 0 deletions
diff --git a/fg21sim/extragalactic/clusters/halo.py b/fg21sim/extragalactic/clusters/halo.py index adc2bc5..9c030a5 100644 --- a/fg21sim/extragalactic/clusters/halo.py +++ b/fg21sim/extragalactic/clusters/halo.py @@ -49,6 +49,7 @@ from ...configs import CONFIGS from ...utils import COSMO from ...utils.units import (Units as AU, UnitConversions as AUC) +from ...utils.convert import Fnu_to_Tb_fast logger = logging.getLogger(__name__) @@ -314,6 +315,53 @@ class RadioHalo: flux = 1e26 * power / (4*np.pi * DL*DL) # [Jy] return flux + def calc_brightness_mean(self, emissivity, frequencies, pixelsize=None): + """ + Calculate the mean surface brightness (power observed per unit + frequency and per unit solid angle) at the specified frequencies + from emissivity. + + NOTE + ---- + If the solid angle that the radio halo extends is smaller than + the specified pixel area, then the halo is assumed to cover a + solid angle of 1 pixel. + + Parameters + ---------- + emissivity : float, or 1D `~numpy.ndarray` + The synchrotron emissivity at multiple frequencies. + Unit: [erg/s/cm^3/Hz] + frequencies : float, or 1D `~numpy.ndarray` + The frequencies where to calculate the synchrotron emissivity. + Unit: [MHz] + pixelsize : float, optional + The pixel size of the output simulated sky image. + Unit: [arcsec] + + Returns + ------- + Tb : float, or 1D `~numpy.ndarray` + The mean surface brightness at each frequency. + Unit: [K] <-> [Jy/pixel] + """ + omega = np.pi * self.angular_radius**2 # [arcsec^2] + if pixelsize: + pixelarea = pixelsize ** 2 # [arcsec^2] + if omega < pixelarea: + omega = pixelarea + logger.warning("Halo sky coverage (%.2f [arcsec^2])" % omega, + " < pixel area (%.2f [arcsec^2])" % pixelarea) + + flux = self.calc_flux(emissivity) + Tb = [Fnu_to_Tb_fast(Fnu, omega, freq) + for Fnu, freq in zip(np.array(flux, ndmin=1), + np.array(frequencies, ndmin=1))] + if len(Tb) == 1: + return Tb[0] + else: + return np.array(Tb) + def fp_injection(self, gamma, t=None): """ Electron injection (rate) term for the Fokker-Planck equation. |