Light-Curves Class

Everything related to light curves is devided into two classes: the Lightcurve class representing a single light curve, and the Lightcurves class representing multi-colour light curves.

class piscola.lightcurves_class.Lightcurve(band, lcs_df)

Light curve class.

__init__(band, lcs_df)
Parameters:

  • band (str) – Light-curve filter/band name.

  • lcs_df (Dataframe) – Light-curve data: times, fluxes, flux_errors, magnitudes, mag_errors and magnitude system.

get_dm15()

Calculates the classic parameter \(\Delta m_{15}\) (Phillips 1993), but using the epoch of peak magnitude of the current light curve as reference (not necessarily \(B\) band).

get_max()

Calculates the peak magnitude (\(m_{max}\)) and its epoch (\(t_{max}\)).

mask_lc(mask, copy=False)

Masks the light-curve data with the given mask.

Parameters:

  • mask (bool, default False) – Mask to apply to the light curve.

  • mask – If True, the masked light curves are saved on separate arrays.

class piscola.lightcurves_class.Lightcurves(lcs_df)

Multi-colour light curves class.

__init__(lcs_df)
get_colour_stretch(band1, band2)

Calculates the colour stretch parameter (Burns et al. 2014).

The formula used is \((T(band1-band2)_{max} - T_{max}/30)\), where \(T(band1−band2)_{max}\) is the time of maximum (reddest colour) in the \((band1−band2)\) colour curve and \(T_{max}\) is the epoch of peak magnitude in band1.

Parameters:

  • band1 (str) – Name of first band.

  • band2 (str) – Name of second band.

Returns:

  • stretch (float) – Colour-stretch parameter.

  • stretch_err (float) – Uncertainty on the colour-stretch parameter.

get_lc_params()

Calculates the peak magnitude (\(m_{max}\)), its epoch (\(t_{max}\)) and \(\Delta m_{15}\) for all bands.

get_max_colour(band1, band2)

Calculates the colour at the epoch of peak magnitude in band1.

The colour is \((band1 - band2)\) at the time of peak magnitude in band1.

Parameters:

  • band1 (str) – Name of first band.

  • band2 (str) – Name of second band.

Returns:

  • colour (float) – Colour at the epoch of peak magnitude in band1.

  • colour_err (float) – Uncertainty on the colour parameter.