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Emissivity

emissivity

XrayEmissivity

Bases: Module

3D Xray emissivity build with temperature, cooling function, density model. It depends on the redshift of the cluster, since the cooling function is precomputed using XSPEC. The default models are the ones used in the papers i.e. Vikhlinin for density, Ghirardini for temperature and the interpolated cooling function.

Source code in src/emissivity.py 
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class XrayEmissivity(hk.Module):
    """
    3D Xray emissivity build with temperature, cooling function, density model.
    It depends on the redshift of the cluster, since the cooling function is precomputed using XSPEC.
    The default models are the ones used in the papers i.e. Vikhlinin for density, Ghirardini for temperature
    and the interpolated cooling function.
    """
    def __init__(self, TZ_grid_to_interp_from = '/xifu/home/mola/SBI_Turbulence/data/flux_table_APEC_oldXIFU.npy'):
        super(XrayEmissivity, self).__init__()
        self.squared_density = VikhlininModel()
        self.temperature = GhirardiniModel()
        self.abundance = XCOPAbundance()
        self.cooling_function = APECEmissivity(TZ_grid_to_interp_from = TZ_grid_to_interp_from)
        self.cosmo = LambdaCDM(H0 = 70, Om0 = 0.3, Ode0= 0.7)


    def __call__(self, r,
                exposure = 125e3, 
                z = 0.1, 
                pixsize_cm = 1., 
                filling_factor= (271/275)**2):
        """
        Compute the emissivity at a given radius, including $N_H$ absorption.

        Parameters:
            r (jnp.array): radius in units of $R_{500}$
            z (float): Redshift of the cluster
            pixsize_cm (float) : Projected of the pixel in the cluster, in centimeters
            filling_factor (float) : Filling factor of the array (absorber size / pixel pitch)
        """

        angular_distance = self.cosmo.angular_diameter_distance(z).value * u.megaparsec.to(u.cm) #cm
        norm = self.squared_density(r) * 1e-14 / (4 *jnp.pi* (angular_distance*(1+z))**2 ) / 1.2

        factor = filling_factor * exposure * pixsize_cm**3

        return self.cooling_function(self.abundance(r), self.temperature(r)) * norm * factor

__call__(r, exposure=125000.0, z=0.1, pixsize_cm=1.0, filling_factor=271 / 275 ** 2)

Compute the emissivity at a given radius, including \(N_H\) absorption.

Parameters:

Name Type Description Default
r array

radius in units of \(R_{500}\)

 required
z float

Redshift of the cluster

 0.1
pixsize_cm float)

Projected of the pixel in the cluster, in centimeters

 1.0
filling_factor float)

Filling factor of the array (absorber size / pixel pitch)

 271 / 275 ** 2
Source code in src/emissivity.py 
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def __call__(self, r,
            exposure = 125e3, 
            z = 0.1, 
            pixsize_cm = 1., 
            filling_factor= (271/275)**2):
    """
    Compute the emissivity at a given radius, including $N_H$ absorption.

    Parameters:
        r (jnp.array): radius in units of $R_{500}$
        z (float): Redshift of the cluster
        pixsize_cm (float) : Projected of the pixel in the cluster, in centimeters
        filling_factor (float) : Filling factor of the array (absorber size / pixel pitch)
    """

    angular_distance = self.cosmo.angular_diameter_distance(z).value * u.megaparsec.to(u.cm) #cm
    norm = self.squared_density(r) * 1e-14 / (4 *jnp.pi* (angular_distance*(1+z))**2 ) / 1.2

    factor = filling_factor * exposure * pixsize_cm**3

    return self.cooling_function(self.abundance(r), self.temperature(r)) * norm * factor