def test_apcorrect1_FUV(self):
aper = np.array([1.5,2.3,3.8,6.0,9.0,12.8,17.3,30.,60.,90.])/3600.
dmag = [1.65,0.96,0.36,0.15,0.1,0.09,0.07,0.06,0.03,0.01]
for i in np.arange(len(aper)):
self.assertAlmostEqual(gt.apcorrect1(aper[i],'FUV'),dmag[i])
if aper[i]<aper[-1]:
self.assertAlmostEqual(gt.apcorrect1((aper[i]+aper[i+1])/2.,'FUV'),(dmag[i]+dmag[i+1])/2.)
self.assertAlmostEqual(gt.apcorrect1(aper[-1]+10,'FUV'),0.)
def test_apcorrect1_NUV(self):
aper = np.array([1.5,2.3,3.8,6.0,9.0,12.8,17.3,30.,60.,90.])/3600.
dmag = [2.09,1.33,0.59,0.23,0.13,0.09,0.07,0.04,-0.00,-0.01]
for i,a in enumerate(aper[:-1]):
self.assertAlmostEqual(gt.apcorrect1(aper[i],'NUV'),dmag[i])
if aper[i]<aper[-2]:
self.assertAlmostEqual(gt.apcorrect1((aper[i]+aper[i+1])/2.,'NUV'),(dmag[i]+dmag[i+1])/2.)
self.assertAlmostEqual(gt.apcorrect1(aper[-1],'NUV'),0.)
self.assertAlmostEqual(gt.apcorrect1(aper[-1]+10,'NUV'),0.)
def apcorrect_cps(lc, band, aper=gt.aper2deg(7)):
""" Apply the aperture correction in units of linear counts-per-second.
Aperture correction is linear in magnitude units, so convert the count rate
into AB mag, correct it, and then convert it back.
"""
return (gt.mag2counts(
gt.counts2mag(lc['cps'].values, band) - gt.apcorrect1(aper, band),
band))
def gphot_params(band, skypos, radius, annulus=None, verbose=0, detsize=1.25,
stepsz=None, trange=None):
"""
Populate a dict() with parameters that are constant over all bins.
:param band: The band being used, either 'FUV' or 'NUV'.
:type band: str
:param skypos: A two-element list containing the RA and DEC.
:type skypos: list
:param radius: Radius of the photometric aperture in degrees.
:type radius: float
:param annulus: A two-element list containing the inner and outer radius
to use for background subtraction during aperture photometry, in
degrees.
:type annulus: list
:param verbose: Level of verbosity, 0 = minimum verbosity.
:type verbose: int
:param detsize: Effective diameter, in degrees, of the field-of-view.
:type detsize: float
:param stepsz: Size of time bin to use, in seconds.
:type stepsz: float
:param trange: The start and end timestamps to consider, in GALEX time
:type trange: list
:returns: dict -- The set of parameters that are constant across all bins.
"""
apsourcecnt, bgsourcecnt, bgsourcemag = bg_contamination(
band, skypos, radius, annulus=annulus)
return {'band':band, 'ra0':skypos[0], 'dec0':skypos[1], 'skypos':skypos,
'trange':trange, 'radius':radius, 'annulus':annulus,
'stepsz':stepsz, 'verbose':verbose, 'detsize':detsize,
'apcorrect1':gxt.apcorrect1(radius, band),
'apcorrect2':gxt.apcorrect2(radius, band),
'detbg':gxt.detbg(mc.area(radius), band),
'n_apersources':apsourcecnt,'n_bgsources':bgsourcecnt,
'max_bgmag':bgsourcemag,'version':__version__,}
def calculate_flare_energy(lc,
frange,
distance,
binsize=30,
band='NUV',
effective_widths={
'NUV': 729.94,
'FUV': 255.45
},
quiescence=None):
""" Calculates the energy of a flare in erg. """
if not quiescence:
q, _ = get_inff(lc)
# Convert to aperture-corrected flux
q = gt.mag2counts(
gt.counts2mag(q, band) - gt.apcorrect1(gt.aper2deg(6), band), band)
else:
q = quiescence[0]
# Convert from parsecs to cm
distance_cm = distance * 3.086e+18
if 'cps_apcorrected' in lc.keys():
# Converting from counts / sec to flux units.
flare_flux = (np.array(
gt.counts2flux(np.array(lc.iloc[frange]['cps_apcorrected']), band))
- gt.counts2flux(q, band))
else:
# Really need to have aperture-corrected counts/sec.
raise ValueError("Need aperture-corrected cps fluxes to continue.")
# Zero any flux values where the flux is below the INFF so that we don't subtract from the total flux!
flare_flux = np.array([0 if f < 0 else f for f in flare_flux])
flare_flux_err = gt.counts2flux(np.array(lc.iloc[frange]['cps_err']), band)
tbins = (np.array(lc.iloc[frange]['t1'].values) -
np.array(lc.iloc[frange]['t0'].values))
# Caluclate the area under the curve.
integrated_flux = (binsize * flare_flux).sum()
"""
GALEX effective widths from
http://svo2.cab.inta-csic.es/svo/theory/fps3/index.php?id=GALEX/GALEX.NUV
width = 729.94 A
http://svo2.cab.inta-csic.es/svo/theory/fps3/index.php?id=GALEX/GALEX.FUV
width = 255.45 A
"""
# Convert integrated flux to a fluence using the GALEX effective widths.
fluence = integrated_flux * effective_widths[band]
fluence_err = (np.sqrt(
((gt.counts2flux(lc.iloc[frange]['cps_err'], band) * binsize)**
2).sum()) * effective_widths[band])
energy = (4 * np.pi * (distance_cm**2) * fluence)
energy_err = (4 * np.pi * (distance_cm**2) * fluence_err)
return energy, energy_err
def gphot_params(band,
skypos,
radius,
annulus=None,
verbose=0,
detsize=1.25,
stepsz=None,
trange=None):
"""
Populate a dict() with parameters that are constant over all bins.
:param band: The band being used, either 'FUV' or 'NUV'.
:type band: str
:param skypos: A two-element list containing the RA and DEC.
:type skypos: list
:param radius: Radius of the photometric aperture in degrees.
:type radius: float
:param annulus: A two-element list containing the inner and outer radius
to use for background subtraction during aperture photometry, in
degrees.
:type annulus: list
:param verbose: Level of verbosity, 0 = minimum verbosity.
:type verbose: int
:param detsize: Effective diameter, in degrees, of the field-of-view.
:type detsize: float
:param stepsz: Size of time bin to use, in seconds.
:type stepsz: float
:param trange: The start and end timestamps to consider, in GALEX time
:type trange: list
:returns: dict -- The set of parameters that are constant across all bins.
"""
apsourcecnt, bgsourcecnt, bgsourcemag = bg_contamination(band,
skypos,
radius,
annulus=annulus)
return {
'band': band,
'ra0': skypos[0],
'dec0': skypos[1],
'skypos': skypos,
'trange': trange,
'radius': radius,
'annulus': annulus,
'stepsz': stepsz,
'verbose': verbose,
'detsize': detsize,
'apcorrect1': gxt.apcorrect1(radius, band),
'apcorrect2': gxt.apcorrect2(radius, band),
'detbg': gxt.detbg(mc.area(radius), band),
'n_apersources': apsourcecnt,
'n_bgsources': bgsourcecnt,
'max_bgmag': bgsourcemag,
'version': __version__,
}