leauthaud11_model_dictionary¶

halotools.empirical_models.
leauthaud11_model_dictionary
(threshold=10.5, **kwargs)[source] [edit on github]¶ Dictionary to build an HODstyle based on Leauthaud et al. (2011), arXiv:1103.2077. The behavior of this model is governed by an assumed underlying stellartohalomass relation.
See Leauthaud et al. (2011) Composite Model for a tutorial on this model.
There are two populations, centrals and satellites. Central occupation statistics are given by a nearest integer distribution with first moment given by an
erf
function; the class governing this behavior isLeauthaud11Cens
. Central galaxies are assumed to reside at the exact center of the host halo; the class governing this behavior isTrivialPhaseSpace
.Satellite occupation statistics are given by a Poisson distribution with first moment given by a power law that has been truncated at the lowmass end; the class governing this behavior is
Leauthaud11Sats
; satellites in this model follow an (unbiased) NFW profile, as governed by theNFWPhaseSpace
class.This composite model is built by the
HodModelFactory
.Parameters: threshold : float, optional
Stellar mass threshold of the mock galaxy sample. Default value is specified in the
model_defaults
module.concentration_binning : tuple, optional
Threeelement tuple. The first entry will be the minimum value of the concentration in the lookup table for the satellite NFW profile, the second entry the maximum, the third entry the linear spacing of the grid. Default is set in
model_defaults
. If highprecision is not required, the lookup tables will build much faster ifconcentration_binning
is set to (1, 25, 0.5).Returns: model_dictionary : dict
Dictionary passed to
HodModelFactory
Examples
>>> from halotools.empirical_models import HodModelFactory >>> model_dictionary = leauthaud11_model_dictionary() >>> model_instance = HodModelFactory(**model_dictionary)
The default settings are set in the
model_defaults
module. To load a model based on a different threshold and redshift:>>> model_dictionary = leauthaud11_model_dictionary(threshold = 11, redshift = 1) >>> model_instance = HodModelFactory(**model_dictionary)
For this model, you can also use the following syntax candy, which accomplishes the same task as the above:
>>> from halotools.empirical_models import PrebuiltHodModelFactory >>> model_instance = PrebuiltHodModelFactory('leauthaud11', threshold = 11, redshift = 1)
As with all instances of the
PrebuiltHodModelFactory
, you can populate a mock by passing the model a halo catalog:>>> from halotools.sim_manager import FakeSim >>> halocat = FakeSim(redshift = model_instance.redshift) >>> model_instance.populate_mock(halocat)