Source code for lenstronomy.SimulationAPI.ObservationConfig.DES
"""Provisional DES instrument and observational settings.
See Optics and Observation Conditions spreadsheet at
https://docs.google.com/spreadsheets/d/1pMUB_OOZWwXON2dd5oP8PekhCT5MBBZJO1HV7IMZg4Y/edit?usp=sharing for list of
sources. """
import lenstronomy.Util.util as util
__all__ = ['DES']
g_band_obs = {'exposure_time': 90.,
'sky_brightness': 22.01,
'magnitude_zero_point': 26.58,
'num_exposures': 10,
'seeing': 1.12,
'psf_type': 'GAUSSIAN'}
r_band_obs = {'exposure_time': 90.,
'sky_brightness': 21.15,
'magnitude_zero_point': 26.78,
'num_exposures': 10,
'seeing': 0.96,
'psf_type': 'GAUSSIAN'}
i_band_obs = {'exposure_time': 90.,
'sky_brightness': 19.89,
'magnitude_zero_point': 26.75,
'num_exposures': 10,
'seeing': 0.88,
'psf_type': 'GAUSSIAN'}
z_band_obs = {'exposure_time': 90.,
'sky_brightness': 18.72,
'magnitude_zero_point': 26.48,
'num_exposures': 10,
'seeing': 0.84,
'psf_type': 'GAUSSIAN'}
Y_band_obs = {'exposure_time': 45.,
'sky_brightness': 17.96,
'magnitude_zero_point': 25.40,
'num_exposures': 10,
'seeing': 0.9,
'psf_type': 'GAUSSIAN'}
"""
:keyword exposure_time: exposure time per image (in seconds)
:keyword sky_brightness: sky brightness (in magnitude per square arcseconds in units of electrons)
:keyword magnitude_zero_point: magnitude in which 1 count (e-) per second per arcsecond square is registered
:keyword num_exposures: number of exposures that are combined (depends on coadd_years)
:keyword seeing: Full-Width-at-Half-Maximum (FWHM) of PSF
:keyword psf_type: string, type of PSF ('GAUSSIAN' supported)
"""
[docs]class DES(object):
"""
class contains DES instrument and observation configurations
"""
def __init__(self, band='g', psf_type='GAUSSIAN', coadd_years=3):
"""
:param band: string, 'g', 'r', 'i', 'z', or 'Y' supported. Determines obs dictionary.
:param psf_type: string, type of PSF ('GAUSSIAN' supported).
:param coadd_years: int, number of years corresponding to num_exposures in obs dict. Currently supported: 1-6.
"""
if band == 'g':
self.obs = g_band_obs
elif band == 'r':
self.obs = r_band_obs
elif band == 'i':
self.obs = i_band_obs
elif band == 'z':
self.obs = z_band_obs
elif band == 'Y':
self.obs = Y_band_obs
else:
raise ValueError("band %s not supported! Choose 'g', 'r', 'i', 'z', or 'Y'." % band)
if psf_type != 'GAUSSIAN':
raise ValueError("psf_type %s not supported!" % psf_type)
if coadd_years > 6 or coadd_years < 1:
raise ValueError(" %s coadd_years not supported! Choose an integer between 1 and 6." % coadd_years)
elif coadd_years != 3:
self.obs['num_exposures'] = (coadd_years * 10) // 3
self.camera = {'read_noise': 7,
'pixel_scale': 0.263,
'ccd_gain': 4,
}
"""
:keyword read_noise: std of noise generated by read-out (in units of electrons)
:keyword pixel_scale: scale (in arcseconds) of pixels
:keyword ccd_gain: electrons/ADU (analog-to-digital unit).
"""
[docs] def kwargs_single_band(self):
"""
:return: merged kwargs from camera and obs dicts
"""
kwargs = util.merge_dicts(self.camera, self.obs)
return kwargs