57def getDESSystemTransmission():
58 """Return a nested dictionary of TransmissionCurves describing the
59 system throughput (optics + filter + detector) at the location of
60 each detector.
61
62 Outer dictionary keys are string dates (YYYY-MM-DD). The next level
63 dictionary maps the physical filter name to another dict. The inner
64 dict is keyed by detector number.
65 """
66
67
68 bands = ["g", "r", "i", "z", "Y"]
69
70 filter_dict = {}
71 for band in bands:
72 for filter_def in DECAM_FILTER_DEFINITIONS:
73 if band == filter_def.band:
74 physical_filter = filter_def.physical_filter
75 break
76
77 table = astropy.io.fits.getdata(
78 os.path.join(DATA_DIR, "des", f"{band}_band_per_detector_throughput.fits"),
79 )
80
81 detector_dict = {}
82 for index in range(table['throughput_ccd'].shape[1]):
83
84 detector = index + 1
85
86 tput = TransmissionCurve.makeSpatiallyConstant(
87 throughput=table["throughput_ccd"][:, index].astype(np.float64),
88 wavelengths=table["lambda"].astype(np.float64),
89 throughputAtMin=0.0,
90 throughputAtMax=0.0,
91 )
92
93 detector_dict[detector] = tput
94
95 filter_dict[physical_filter] = detector_dict
96
97 return {DECAM_BEGIN: filter_dict}
