reggae.asymptotic

Classes

asymptotic

Module Contents

class reggae.asymptotic.asymptotic
_pair(nu0, h, w, d02)

Define a pair as the sum of two Lorentzians.

A pair is assumed to consist of an l=0 and an l=2 mode. The widths are assumed to be identical, and the height of the l=2 mode is scaled relative to that of the l=0 mode. The frequency of the l=2 mode is the l=0 frequency minus the small separation.

Parameters

nu0float

Frequency of the l=0 (muHz).

hfloat

Height of the l=0 (SNR).

wfloat

The mode width (identical for l=2 and l=0) (log10(muHz)).

d02float

The small separation (muHz).

Returns

pair_modelarray

The SNR as a function of frequency of a mode pair.

_lor(nu0, h, w)

Lorentzian to describe a mode.

Parameters

nu0float

Frequency of lorentzian (muHz).

hfloat

Height of the lorentizan (SNR).

wfloat

Full width of the lorentzian (muHz).

Returns

modendarray

The SNR as a function frequency for a lorentzian.

_get_nmax(dnu, numax, eps)

Compute radial order at numax.

Compute the radial order at numax, which in this implimentation of the asymptotic relation is not necessarily integer.

Parameters

numaxfloat

Frequency of maximum power of the p-mode envelope (muHz).

dnufloat

Large separation of l=0 modes (muHz).

epsfloat

Epsilon phase term in asymptotic relation.

Returns

nmaxfloat

non-integer radial order of maximum power of the p-mode envelope

_get_n_p(nmax)

Compute radial order numbers.

Get the enns that will be included in the asymptotic relation fit. These are all integer.

Parameters

nmaxfloat

Frequency of maximum power of the p-mode envelope.

nordersint

Total number of radial orders to consider.

Returns

ennsndarray

Numpy array of norders radial orders (integers) around nu_max (nmax).

_P_envelope(nu, hmax, numax, width)

Power of the seismic p-mode envelope

Computes the power at frequency nu in the p-mode envelope from a Gaussian distribution. Used for computing mode heights.

Parameters

nufloat

Frequency (muHz).

hmaxfloat

Height of p-mode envelope (SNR).

numaxfloat

Frequency of maximum power of the p-mode envelope (muHz).

widthfloat

Width of the p-mode envelope (muHz).

Returns

hfloat

Power at frequency nu (SNR)

_get_freq_range(numax)

Get frequency range around numax for model

Returns a boolean array corresponding to the frequency bins that span the p-mode envelope.

The range is set to be -/+ Dnu from the lowest/heighest radial order.

Parameters

numaxfloat

Frequency of maximum power of the p-mode envelope (muHz).

Returns

idxbool

Boolean array pick out the frequency range of the p-mode envelope.

_asymptotic_relation(numax, dnu, eps, alpha)

Compute the l=0 mode frequencies from the asymptotic relation for p-modes

Parameters

numaxfloat

Frequency of maximum power of the p-mode envelope (muHz).

dnufloat

Large separation of l=0 modes (muHz).

epsfloat

Epsilon phase term in asymptotic relation (unitless).

alphafloat

Curvature factor of l=0 ridge (second order term, unitless).

Returns

nu0sndarray

Array of l=0 mode frequencies from the asymptotic relation (muHz).

asymptotic_model(theta_asy)

Constructs a spectrum model from the asymptotic relation.

The asymptotic relation for p-modes with angular degree, l=0, is defined as:

$nu_nl = (n + epsilon + lpha/2(n - nmax)^2) * log{dnu}$ ,

where nmax = numax / dnu - epsilon.

We separate the l=0 and l=2 modes by the small separation d02.

Parameters

dnufloat

Large separation log10(muHz)

lognumaxfloat

Frequency of maximum power of the p-mode envelope log10(muHz)

epsfloat

Phase term of the asymptotic relation (unitless)

alphafloat

Curvature of the asymptotic relation log10(unitless)

d02float

Small separation log10(muHz)

loghmaxfloat

Gaussian height of p-mode envelope log10(SNR)

logenvwidthfloat

Gaussian width of the p-mode envelope log10(muHz)

logmodewidthfloat

Width of the modes (log10(muHz))

*argsarray-like

List of additional parameters (Teff, bp_rp) that aren’t actually used to construct the spectrum model, but just for evaluating the prior.

Returns

modelndarray

spectrum model around the p-mode envelope