NcHaloBiasSTEllip

NcHaloBiasSTEllip — Sheth-Tormen elliptical halo bias function type.

Functions

Properties

double a Read / Write / Construct Only
double b Read / Write / Construct Only
double c Read / Write / Construct Only
double critical-delta Read / Write / Construct Only

Object Hierarchy

    GObject
    ╰── NcHaloBias
        ╰── NcHaloBiasSTEllip

Description

Object implementation to compute the halo bias function given the Sheth-Tormen mass function for elliptical collapse. A description of the function is given below. Check nc_halo_bias.c for a description of halo biases and nc_multiplicity_func_st.c for the Sheth-Tormen mass function.

The Sheth-Tormen bias can be obtained by considering an approximation where the fluctuations around the background density contrats are described by a constant barrier that depends on the collapse. For an elliptical collapse, the bias is given by \begin{align} b(\nu)=1+\frac{1}{\delta_{\mathrm{sc}}(z)} \left[a \nu^2+ b\left(a \nu^2\right)^{1-c} -\frac{\left(a \nu^2\right)^c}{\sqrt{a}\left(a \nu^2\right)^c+b(1-c)(1-c / 2)}\right] \end{align} where $b(\nu)$ is the bias, $\delta_c$ is the critical threshold, $\nu = \frac{\delta_c}{\sigma}$ and $(a, b, c)$ are free parameters of the mass function that dictates the shape of the barrier.

The user must provide input the values: NcHaloMassFunction , delta_c , a , p - nc_halo_bias_st_spher_new_full().

Functions

nc_halo_bias_st_ellip_new ()

NcHaloBiasSTEllip *
nc_halo_bias_st_ellip_new (NcHaloMassFunction *mfp);

Creates a new NcHaloBiasSTEllip object with undefined parameters.

[constructor]

Parameters

Returns

A new NcHaloBias.


nc_halo_bias_st_ellip_new_full ()

NcHaloBiasSTEllip *
nc_halo_bias_st_ellip_new_full (NcHaloMassFunction *mfp,
                                gdouble delta_c,
                                gdouble a,
                                gdouble b,
                                gdouble c);

Creates a new NcHaloBiasSTEllip object with the input values.

[constructor]

Parameters

mfp

a NcHaloMassFunction

 

delta_c

Density contrast critical threshold

 

a

Parameter that dictates the shape of the barrier.

 

b

Parameter that dictates the shape of the barrier.

 

c

Parameter that dictates the shape of the barrier.

 

Returns

A new NcHaloBias.


nc_halo_bias_st_ellip_set_delta_c ()

void
nc_halo_bias_st_ellip_set_delta_c (NcHaloBiasSTEllip *biasf_st_ellip,
                                   gdouble delta_c);

Sets the value delta_c to the “critical-delta” property.

Parameters

biasf_st_ellip

a NcHaloBiasSTEllip.

 

delta_c

value of “critical-delta”.

 

nc_halo_bias_st_ellip_get_delta_c ()

gdouble
nc_halo_bias_st_ellip_get_delta_c (const NcHaloBiasSTEllip *biasf_st_ellip);

Parameters

biasf_st_ellip

a NcHaloBiasSTEllip.

 

Returns

the value of “critical_delta” property.


nc_halo_bias_st_ellip_set_a ()

void
nc_halo_bias_st_ellip_set_a (NcHaloBiasSTEllip *biasf_st_ellip,
                             gdouble a);

Sets the value a to the “a” property.

Parameters

biasf_st_ellip

a NcHaloBiasSTEllip.

 

a

value of “a”.

 

nc_halo_bias_st_ellip_get_a ()

gdouble
nc_halo_bias_st_ellip_get_a (const NcHaloBiasSTEllip *biasf_st_ellip);

Parameters

biasf_st_ellip

a NcHaloBiasSTEllip.

 

Returns

the value of “a” property.


nc_halo_bias_st_ellip_set_b ()

void
nc_halo_bias_st_ellip_set_b (NcHaloBiasSTEllip *biasf_st_ellip,
                             gdouble b);

Sets the value b to the “b” property.

Parameters

biasf_st_ellip

a NcHaloBiasSTEllip.

 

b

value of “b”.

 

nc_halo_bias_st_ellip_get_b ()

gdouble
nc_halo_bias_st_ellip_get_b (const NcHaloBiasSTEllip *biasf_st_ellip);

Parameters

biasf_st_ellip

a NcHaloBiasSTEllip.

 

Returns

the value of “b” property.


nc_halo_bias_st_ellip_set_c ()

void
nc_halo_bias_st_ellip_set_c (NcHaloBiasSTEllip *biasf_st_ellip,
                             gdouble c);

Sets the value c to the “c” property.

Parameters

biasf_st_ellip

a NcHaloBiasSTEllip.

 

c

value of “c”.

 

nc_halo_bias_st_ellip_get_c ()

gdouble
nc_halo_bias_st_ellip_get_c (const NcHaloBiasSTEllip *biasf_st_ellip);

Parameters

biasf_st_ellip

a NcHaloBiasSTEllip.

 

Returns

the value of “c” property.

Property Details

The “a” property

  “a”                        double

Parameter that dictates the shape of the barrier. (check limits values)

Owner: NcHaloBiasSTEllip

Flags: Read / Write / Construct Only

Default value: 0.707


The “b” property

  “b”                        double

Parameter that dictates the shape of the barrier. (check limits values)

Owner: NcHaloBiasSTEllip

Flags: Read / Write / Construct Only

Default value: 0.5


The “c” property

  “c”                        double

Parameter that dictates the shape of the barrier. (check limits values)

Owner: NcHaloBiasSTEllip

Flags: Read / Write / Construct Only

Default value: 0.6


The “critical-delta” property

  “critical-delta”           double

Critical delta.

Owner: NcHaloBiasSTEllip

Flags: Read / Write / Construct Only

Default value: 1.686