def getExtinction(ra, dec, a_lambda=None):
"""
Estimate the Galactic extinction for HSC filters.
Parameters:
ra, dec : The input coordinates can be arrays
"""
# Check the input, if it's scalar, convert to array
if not hasattr(ra, "__len__") or not hasattr(dec, "__len__"):
ra = np.asrray([ra])
dec = np.asarray([dec])
if len(ra) != len(dec):
raise Exception("## The RA and DEC should contain " +
"same number of elements!")
# First try mwdust from Jo Bovy
try:
import mwdust
sfd = mwdust.SFD(sf10=True)
from astropy.coordinates import SkyCoord
coords = SkyCoord(ra, dec, frame='icrs', unit='deg')
galactic = coords.galactic
l, b = galactic.l, galactic.b
ebv = sfd(l, b, 0)
except ImportError:
try:
# Then try sncosmo
from sncosmo import SFD98Map
dustDir = os.environ.get('DUST_DIR')
if (not os.path.isfile(
os.path.join(dustDir, 'SFD_dust_4096_ngp.fits'))) or (
not os.path.isfile(
os.path.join(dustDir, 'SFD_dust_4096_sgp.fits'))):
print('# DUST_DIR : %s' % dustDir)
raise Exception("# Can not find the SFD dust map!")
else:
sfd = SFD98Map(dustDir)
ebv = sfd.get_ebv((ra, dec))
except ImportError:
raise Exception("# Both mwdust and sncosmo are not available")
if a_lambda is not None:
return (ebv * a_lambda)
else:
return ebv
def radec_extinction(ra, dec, a_lambda=1.0):
"""Estimate the Galactic extinction for HSC filters.
-----------
Parameters:
(ra, dec): (float, float)
The input coordinates can be arrays
a_lambda : optional, default=1.0
Convert the e_bv value into extinction in magnitude unit.
"""
coords = SkyCoord(ra, dec, frame='icrs', unit='deg')
try:
# mwdust by Jo Bovy
import mwdust
sfd = mwdust.SFD(sf10=True)
ebv = sfd(coords.galactic.l.deg, coords.galactic.b.deg, 0)
except ImportError:
try:
# Try querying the IRSA dust map instead
from astroquery.irsa_dust import IrsaDust
extinction_tab = IrsaDust.get_extinction_table(coords)
ebv = (extinction_tab['A_SFD'] / extinction_tab['A_over_E_B_V_SFD'])[1]
except ImportError:
raise Exception("# Need mwdust by Jo Bovy or Astroquery")
return a_lambda * ebv
def load_dust_color(
color,
fname,
df=None,
distance=None,
save=True,
logger=_LOGFILE,
verbose=None,
):
"""PanSTARRS1 dust color.
Parameters
----------
color
fname
df
distance
save
logger
verbose
Returns
-------
dust_c
"""
try:
dust_c = np.load(fname.format(color)) * u.mag
except FileNotFoundError:
if (df is None) or (distance is None):
raise ValueError(
f"load_dust_color({color}) needs *df* & *distance*")
sys.stdout.write(f"could not load {color}")
sys.stdout.flush()
SFDc = mwdust.SFD(filter=f"PS1 {color}")
dust_c = SFDc(df["l"], df["b"], distance.to_value(u.kpc)) * u.mag
if save:
dust_c.value.dump(fname.format(color))
sys.stdout.write(f"\033 -> finised {color}, ")
sys.stdout.flush()
else:
sys.stdout.write(f"\033 {color}, ")
sys.stdout.flush()
return dust_c
def getExtinction(ra, dec, a_lambda=None):
"""
Estimate the Galactic extinction for HSC filters.
Parameters:
ra, dec : The input coordinates can be arrays
"""
# First try mwdust from Jo Bovy
try:
import mwdust
sfd = mwdust.SFD(sf10=True)
from astropy.coordinates import SkyCoord
coords = SkyCoord(ra, dec, frame='icrs', unit='deg')
galactic = coords.galactic
l, b = galactic.l, galactic.b
ebv = sfd(l, b, 0)
except ImportError:
try:
# Then try sncosmo
from sncosmo import SFD98Map
dustDir = os.environ.get('DUST_DIR')
if (not os.path.isfile(
os.path.join(dustDir, 'SFD_dust_4096_ngp.fits'))) or (
not os.path.isfile(
os.path.join(dustDir, 'SFD_dust_4096_sgp.fits'))):
print('# DUST_DIR : %s' % dustDir)
raise Exception("# Can not find the SFD dust map!")
else:
sfd = SFD98Map(dustDir)
ebv = sfd.get_ebv((ra, dec))
except ImportError:
raise Exception("# Both mwdust and sncosmo are not available")
if a_lambda is not None:
return (ebv * a_lambda)
else:
return ebv