588 lines
31 KiB
Python
588 lines
31 KiB
Python
from astropy import units as u
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from .ASensor import ASensor
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from ..IRadiant import IRadiant
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from ..Entry import Entry
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import numpy as np
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from typing import Union, Tuple
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from ..psf.Airy import Airy
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from ..psf.Zemax import Zemax
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from ..psf.FITS import FITS
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from ..SpectralQty import SpectralQty
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from .PixelMask import PixelMask
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from ...lib.logger import logger
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import astropy.constants as const
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import os
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import astropy.io.fits as fits
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class Imager(ASensor):
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"""
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A class for modelling a Image-sensor
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"""
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__encircled_energy: Union[str, float, u.Quantity]
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@u.quantity_input(pixel_geometry=u.pixel, pixel_size="length", sigma_read_out=u.electron ** 0.5 / u.pix,
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center_offset=u.pix, dark_current=u.electron / u.pix / u.second, well_capacity=u.electron)
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def __init__(self, parent: IRadiant, quantum_efficiency: Union[str, u.Quantity],
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pixel_geometry: u.Quantity, pixel_size: u.Quantity, sigma_read_out: u.Quantity,
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dark_current: u.Quantity, well_capacity: u.Quantity, f_number: Union[int, float], common_conf: Entry,
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center_offset: u.Quantity = np.array([0, 0]) << u.pix, shape: str = "circle",
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contained_energy: Union[str, int, float] = "FWHM", aperture_size: u.Quantity = None):
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"""
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Initialize a new Image-sensor model.
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Parameters
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----------
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parent : IRadiant
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The parent element of the optical component from which the electromagnetic radiation is received.
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quantum_efficiency : Union[str, u.Quantity]
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The quantum efficiency of the detector. This can be either the path to the file containing the values of
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the spectral quantum efficiency or the overall quantum efficiency as astropy quantity.
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pixel_geometry : u.Quantity
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The geometry of the pixel array as Quantity in pixels with two entries:
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[number of pixels in x-direction, number of pixels in y-direction]
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pixel_size : length-Quantity
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The edge length of a pixel (assumed to be square).
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sigma_read_out : Quantity
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The RMS-read noise per detector pixel in electrons^0.5 / pixel.
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dark_current : Quantity
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The dark current of a detector pixel in electrons / (pixels * s).
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well_capacity : Quantity
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The pixel's well capacity in electrons.
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f_number : Union[int, float]
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The f-number of the optical system.
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common_conf : Entry
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The common-Entry of the configuration.
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center_offset : u.Quantity
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The offset of the PSF-center relative to the center of the detector array as length-quantity with two
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entries: [offset in x-direction, offset in y-direction]
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shape : str
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The shape of the photometric aperture. Can be either square or circle
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contained_energy : Union[str, int, float]
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The energy contained within the photometric aperture.
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aperture_size : u.Quantity
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The radius respectively the edge length of the photometric aperture.
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"""
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super().__init__(parent)
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if type(quantum_efficiency) == str:
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self.__quantum_efficiency = SpectralQty.fromFile(quantum_efficiency, u.nm, u.electron / u.photon)
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else:
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self.__quantum_efficiency = quantum_efficiency
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self.__pixel_geometry = pixel_geometry
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self.__pixel_size = pixel_size
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self.__sigma_read_out = sigma_read_out
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self.__dark_current = dark_current
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self.__well_capacity = well_capacity
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self.__f_number = f_number
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self.__center_offset = center_offset
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self.__shape = shape
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self.__contained_energy = contained_energy
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self.__aperture_size = aperture_size
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self.__common_conf = common_conf
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# Calculate central wavelength
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self.__central_wl = self.__common_conf.wl_min() + (
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self.__common_conf.wl_max() - self.__common_conf.wl_min()) / 2
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# Parse PSF
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if common_conf.psf.type.lower() == "airy":
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# Use an airy disk as PSF
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self.__psf = Airy(self.__f_number, self.__central_wl, common_conf.d_aperture(), common_conf.psf.osf,
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pixel_size)
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elif common_conf.psf.type.lower() == "zemax":
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# Read PSF from Zemax file
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self.__psf = Zemax(common_conf.psf(), self.__f_number, self.__central_wl, common_conf.d_aperture(),
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common_conf.psf.osf, pixel_size)
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elif common_conf.psf.type.lower() == "fits":
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# Read PSF from FITS-file
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self.__psf = FITS(common_conf.psf(), self.__f_number, self.__central_wl, common_conf.d_aperture(),
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common_conf.psf.osf, pixel_size)
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else:
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logger.error("Unknown PSF type '" + common_conf.psf() + "'.")
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@u.quantity_input(exp_time="time")
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def calcSNR(self, background: SpectralQty, signal: SpectralQty, obstruction: float,
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exp_time: u.Quantity) -> u.dimensionless_unscaled:
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"""
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Calculate the signal to background ratio (SNR) for the given exposure time using the CCD-equation.
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Parameters
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----------
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background : SpectralQty
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The received background radiation
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signal : SpectralQty
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The received signal radiation
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obstruction : float
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The obstruction factor of the aperture as ratio A_ob / A_ap
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exp_time : time-Quantity
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The exposure time to calculate the SNR for.
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Returns
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-------
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snr : Quantity
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The calculated SNR as dimensionless quantity
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"""
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# Calculate the electron currents
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signal_current, background_current, read_noise, dark_current = self.__exposePixels(background, signal,
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obstruction)
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# Calculate the SNR using the CCD-equation
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logger.info("Calculating the SNR...", extra={"spinning": True})
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snr = signal_current.sum() * exp_time / np.sqrt(
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(signal_current + background_current + dark_current).sum() * exp_time + (read_noise ** 2).sum())
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# Print information
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for exp_time_ in exp_time if exp_time.size > 1 else [exp_time]:
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self.__printDetails(signal_current * exp_time_, background_current * exp_time_, read_noise,
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dark_current * exp_time_, "t_exp=%.2f s: " % exp_time_.value)
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self.__output(signal_current * exp_time_, background_current * exp_time_, read_noise,
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dark_current * exp_time_, "texp_%.2f" % exp_time_.value)
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# Return the value of the SNR, ignoring the physical units (electrons^0.5)
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return snr.value * u.dimensionless_unscaled
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@u.quantity_input(snr=u.dimensionless_unscaled)
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def calcExpTime(self, background: SpectralQty, signal: SpectralQty, obstruction: float, snr: u.Quantity) -> u.s:
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"""
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Calculate the necessary exposure time in order to achieve the given SNR.
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Parameters
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----------
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background : SpectralQty
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The received background radiation
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signal : SpectralQty
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The received signal radiation
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obstruction : float
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The obstruction factor of the aperture as ratio A_ob / A_ap
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snr : Quantity
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The SNR for which the necessary exposure time shall be calculated as dimensionless quantity.
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Returns
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-------
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exp_time : Quantity
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The necessary exposure time in seconds.
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"""
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# Calculate the electron currents
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signal_current, background_current, read_noise, dark_current = self.__exposePixels(background, signal,
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obstruction)
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logger.info("Calculating the exposure time...", extra={"spinning": True})
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# Calculate the electron currents for all pixels
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signal_current_tot = signal_current.sum()
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# Fix the physical units of the SNR
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snr = snr * u.electron ** 0.5
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# Calculate the ratio of the background- and dark-current to the signal current as auxiliary variable
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current_ratio = (background_current.sum() + dark_current.sum()) / signal_current_tot
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# Calculate the necessary exposure time as inverse of the CCD-equation
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exp_time = snr ** 2 * (
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1 + current_ratio + np.sqrt((1 + current_ratio) ** 2 + 4 * (read_noise ** 2).sum() / snr ** 2)) / (
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2 * signal_current_tot)
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# Print information
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for snr_, exp_time_ in zip(snr, exp_time) if snr.size > 1 else zip([snr], [exp_time]):
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self.__printDetails(signal_current * exp_time_, background_current * exp_time_, read_noise,
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dark_current * exp_time_, "SNR=%.2f: " % snr_.value)
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self.__output(signal_current * exp_time_, background_current * exp_time_, read_noise,
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dark_current * exp_time_, "snr_%.2f" % snr_.value)
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return exp_time
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# @u.quantity_input(exp_time="time", snr=u.dimensionless_unscaled, target_brightness=[u.mag, u.mag / u.sr])
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def calcSensitivity(self, background: SpectralQty, signal: SpectralQty, obstruction: float, exp_time: u.Quantity,
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snr: u.Quantity, target_brightness: u.Quantity) -> [u.mag, u.mag / u.sr]:
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"""
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Calculate the sensitivity of the telescope detector combination.
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Parameters
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----------
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background : SpectralQty
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The received background radiation
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signal : SpectralQty
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The received signal radiation
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obstruction : float
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The obstruction factor of the aperture as ratio A_ob / A_ap
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exp_time : Quantity
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The exposure time in seconds.
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snr : Quantity
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The SNR for which the sensitivity time shall be calculated.
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target_brightness : Quantity
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The target brightness in mag or mag / sr.
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Returns
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-------
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sensitivity: Quantity
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The sensitivity as limiting apparent star magnitude in mag.
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"""
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# Calculate the electron currents
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signal_current, background_current, read_noise, dark_current = self.__exposePixels(background, signal,
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obstruction)
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logger.info("Calculating the sensitivity...", extra={"spinning": True})
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# Fix the physical units of the SNR
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snr = snr * u.electron ** 0.5
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signal_current_lim = snr * (snr + np.sqrt(
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snr ** 2 + 4 * (exp_time * (background_current.sum() + dark_current.sum()) +
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(read_noise ** 2).sum()))) / (2 * exp_time)
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# Print information
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for snr_, exp_time_, signal_current_lim_ in zip(snr, exp_time, signal_current_lim) if snr.size > 1 else zip(
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[snr], [exp_time], [signal_current_lim]):
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self.__printDetails(signal_current_lim_ * exp_time_, background_current * exp_time_, read_noise,
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dark_current * exp_time_, "SNR=%.2f t_exp=%.2f s: " % (snr_.value, exp_time_.value))
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self.__output(signal_current * signal_current_lim_ / signal_current.sum() * exp_time_,
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background_current * exp_time_, read_noise, dark_current * exp_time_,
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"snr_%.2f_texp_%.2f" % (snr_.value, exp_time_.value))
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return target_brightness - 2.5 * np.log10(signal_current_lim / signal_current.sum()) * target_brightness.unit
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@u.quantity_input(signal=u.electron, background=u.electron, read_noise=u.electron ** 0.5, dark=u.electron)
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def __printDetails(self, signal: u.Quantity, background: u.Quantity, read_noise: u.Quantity,
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dark: u.Quantity, prefix: str = ""):
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"""
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Print details on the signal and noise composition.
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Parameters
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----------
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signal : Quantity
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The collected electrons from the target in electrons.
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background : Quantity
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The collected electrons from the background in electrons.
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read_noise : Quantity
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The read noise in electrons.
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dark : Quantity
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The electrons from the dark current in electrons.
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prefix : str
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The prefix to be used for printing
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Returns
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-------
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"""
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# Calculate the total collected electrons per pixel
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total = signal + background + dark
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# Check for overexposed pixels
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overexposed = total > self.__well_capacity
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if np.any(overexposed):
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# Calculate number of overexposed pixels
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n_overexposed = np.count_nonzero(overexposed)
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# Show a warning for the overexposed pixels
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if n_overexposed == 1:
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logger.warning(prefix + str(n_overexposed) + " pixel is overexposed.")
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else:
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logger.warning(prefix + str(n_overexposed) + " pixels are overexposed.")
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logger.info("--------------------------------------------------------------------------")
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logger.info(prefix + "Collected electrons from target: %1.2e electrons" % signal.sum().value)
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logger.info(prefix + "Collected electrons from background: %1.2e electrons" % background.sum().value)
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logger.info(prefix + "Electrons from dark current: %1.2e electrons" % dark.sum().value)
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logger.info(prefix + "Read noise: %1.2e electrons" % (read_noise ** 2).sum().value)
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logger.info(prefix + "Total collected electrons: %1.2e electrons" % total.sum().value)
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logger.info("--------------------------------------------------------------------------")
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@u.quantity_input(signal=u.electron, background=u.electron, read_noise=u.electron ** 0.5, dark=u.electron)
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def __output(self, signal: u.Quantity, background: u.Quantity, read_noise: u.Quantity,
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dark: u.Quantity, name: str):
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"""
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Write the signal and the noise in electrons to files.
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Parameters
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----------
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signal : Quantity
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The collected electrons from the target in electrons.
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background : Quantity
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The collected electrons from the background in electrons.
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read_noise : Quantity
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The read noise in electrons.
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dark : Quantity
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The electrons from the dark current in electrons.
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name : str
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The name of the configuration.
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Returns
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-------
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"""
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# Concatenate the paths
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path = os.path.join(self.__common_conf.output.path, name)
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try:
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os.makedirs(path, exist_ok=True)
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except FileExistsError:
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logger.warning("Output directory '" + path + "' already exists.")
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# Calculate the indices of nonzero values and create a bounding rectangle
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y, x = np.nonzero(signal)
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y_min = min(y)
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y_max = max(y)
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x_min = min(x)
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x_max = max(x)
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# Write arrays to file
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if self.__common_conf.output.format.lower() == "csv":
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mes = "Range reduced to nonzero values.\nThe origin is in the top left corner, starting with 0.\n" + \
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"Column index range: %d - %d\nRow index range: %d - %d\n" % (y_min, y_max, x_min, x_max)
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np.savetxt(os.path.join(path, "signal.csv"), signal[y_min:(y_max + 1), x_min:(x_max + 1)].value,
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delimiter=",", header="Signal in electrons\n" + mes)
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np.savetxt(os.path.join(path, "background.csv"), background[y_min:(y_max + 1), x_min:(x_max + 1)].value,
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delimiter=",", header="Background in electrons\n" + mes)
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np.savetxt(os.path.join(path, "read_noise.csv"), read_noise[y_min:(y_max + 1), x_min:(x_max + 1)].value,
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delimiter=",", header="Read noise in electrons\n" + mes)
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np.savetxt(os.path.join(path, "dark_noise.csv"), dark[y_min:(y_max + 1), x_min:(x_max + 1)].value,
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delimiter=",", header="Dark noise in electrons\n" + mes)
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elif self.__common_conf.output.format.lower() == "fits":
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mes = "Range reduced to nonzero values. The origin is in the top left corner, starting with 0. " + \
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"Column index range: %d - %d Row index range: %d - %d " % (y_min, y_max, x_min, x_max)
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hdu = fits.PrimaryHDU(header=fits.Header(dict(COMMENT="Simulation data created by ESBO-ETC.",
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TELESCOP="ESBO-ETC")))
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signal_hdu = fits.ImageHDU(signal[y_min:(y_max + 1), x_min:(x_max + 1)].value, name="signal",
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header=fits.Header(dict(COMMENT="Signal in electrons. " + mes,
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TELESCOP="ESBO-ETC")))
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background_hdu = fits.ImageHDU(background[y_min:(y_max + 1), x_min:(x_max + 1)].value, name="background",
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header=fits.Header(dict(COMMENT="Background in electrons. " + mes,
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TELESCOP="ESBO-ETC")))
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read_noise_hdu = fits.ImageHDU(read_noise[y_min:(y_max + 1), x_min:(x_max + 1)].value, name="read noise",
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header=fits.Header(dict(COMMENT="Read noise in electrons. " + mes,
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TELESCOP="ESBO-ETC")))
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dark_hdu = fits.ImageHDU(dark[y_min:(y_max + 1), x_min:(x_max + 1)].value, name="dark noise",
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header=fits.Header(dict(COMMENT="Dark noise in electrons. " + mes,
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TELESCOP="ESBO-ETC")))
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hdul = fits.HDUList([hdu, signal_hdu, background_hdu, read_noise_hdu, dark_hdu])
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hdul.writeto(os.path.join(path, "results.fits"), overwrite=True)
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def __exposePixels(self, background: SpectralQty, signal: SpectralQty,
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obstruction: float) -> Tuple[u.Quantity, u.Quantity, u.Quantity, u.Quantity]:
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"""
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Expose the pixels and calculate the signal and noise electron currents per pixel.
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Parameters
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----------
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background : SpectralQty
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The received background radiation
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signal : SpectralQty
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The received signal radiation
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obstruction : float
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The obstruction factor of the aperture as ratio A_ob / A_ap
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Returns
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-------
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signal_current : Quantity
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The electron current from the target as PixelMask in electrons / s
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background_current : Quantity
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The electron current from the background as PixelMask in electrons / s
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read_noise : Quantity
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The read noise per pixel in electrons
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dark_current : Quantity
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The electron current from the dark noise as PixelMask in electrons / s
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"""
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# Calculate the total incoming electron current
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logger.info("Calculating incoming electron current...", extra={"spinning": True})
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signal_current, size, obstruction, background_current = self.__calcIncomingElectronCurrent(background, signal,
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obstruction)
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# info("Finished calculating incoming electron current", extra={"spinning": False})
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# Initialize a new PixelMask
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mask = PixelMask(self.__pixel_geometry, self.__pixel_size, self.__center_offset)
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if size.lower() == "extended":
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# Target is extended, a diameter of 0 pixels results in a mask with one pixel marked
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d_photometric_ap = 0 * u.pix
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# Mask the pixels to be exposed
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mask.createPhotometricAperture("circle", d_photometric_ap / 2, np.array([0, 0]) << u.pix)
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else:
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# Target is a point source
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if self.__aperture_size is not None:
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# Us ethe aperture size as diameter
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d_photometric_ap = self.__aperture_size
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else:
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# Calculate the diameter of the photometric aperture from the given contained energy
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logger.info("Calculating the diameter of the photometric aperture...",
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extra={"spinning": True})
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d_photometric_ap = self.__calcPhotometricAperture(obstruction)
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# Mask the pixels to be exposed
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mask.createPhotometricAperture(self.__shape, d_photometric_ap / 2)
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# Calculate the background current PixelMask
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background_current = mask * background_current * u.pix
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# Calculate the read noise PixelMask
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read_noise = mask * self.__sigma_read_out * u.pix
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# Calculate the dark current PixelMask
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dark_current = mask * self.__dark_current * u.pix
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if self.__aperture_size is None and size.lower() != "extended":
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if type(self.__contained_energy) == str:
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if self.__contained_energy.lower() == "peak":
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logger.info("The radius of the photometric aperture is %.2f pixels. This equals the peak value" % (
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d_photometric_ap.value / 2))
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elif self.__contained_energy.lower() == "fwhm":
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logger.info("The radius of the photometric aperture is %.2f pixels. This equals the FWHM" % (
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d_photometric_ap.value / 2))
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elif self.__contained_energy.lower() == "min":
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logger.info(
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"The radius of the photometric aperture is %.2f pixels. This equals the first minimum" % (
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d_photometric_ap.value / 2))
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else:
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logger.info(
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"The radius of the photometric aperture is %.2f pixels. This equals %.0f%% encircled energy" % (
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d_photometric_ap.value / 2, self.__contained_energy))
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logger.info("The photometric aperture contains " + str(np.count_nonzero(mask)) + " pixels.")
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if size.lower() != "extended":
|
|
# Map the PSF onto the pixel mask in order to get the relative irradiance of each pixel
|
|
logger.info("Mapping the PSF onto the pixel grid...", extra={"spinning": True})
|
|
mask = self.__psf.mapToPixelMask(mask,
|
|
getattr(getattr(self.__common_conf, "jitter_sigma", None), "val", None),
|
|
obstruction)
|
|
# Calculate the signal current PixelMask
|
|
signal_current = mask * signal_current
|
|
return signal_current, background_current, read_noise, dark_current
|
|
|
|
def __calcPhotometricAperture(self, obstruction: float) -> u.Quantity:
|
|
"""
|
|
Calculate the diameter of the photometric aperture
|
|
|
|
Parameters
|
|
----------
|
|
obstruction : float
|
|
The obstruction factor as A_ob / A_ap.
|
|
|
|
Returns
|
|
-------
|
|
d_photometric_ap : Quantity
|
|
The diameter of the photometric aperture in pixels.
|
|
"""
|
|
# Calculate the reduced observation angle
|
|
jitter_sigma = getattr(getattr(self.__common_conf, "jitter_sigma", None), "val", None)
|
|
reduced_observation_angle = self.__psf.calcReducedObservationAngle(self.__contained_energy, jitter_sigma,
|
|
obstruction)
|
|
logger.debug("Reduced observation angle: %.2f" % reduced_observation_angle.value)
|
|
# Calculate angular width of PSF
|
|
observation_angle = (reduced_observation_angle * self.__central_wl / self.__common_conf.d_aperture() *
|
|
180.0 / np.pi * 3600).decompose() * u.arcsec
|
|
# Calculate FOV of a single pixel
|
|
pixel_fov = (self.__pixel_size / (self.__f_number * self.__common_conf.d_aperture()) * 180.0 /
|
|
np.pi * 3600).decompose() * u.arcsec
|
|
# Calculate the radius of the photometric aperture in pixels
|
|
d_photometric_ap = observation_angle / pixel_fov
|
|
return d_photometric_ap * u.pix
|
|
|
|
def __calcIncomingElectronCurrent(self, background: SpectralQty, signal: SpectralQty,
|
|
obstruction: float) -> Tuple[u.Quantity, str, float, u.Quantity]:
|
|
"""
|
|
Calculate the detected electron current of the signal and the background.
|
|
|
|
Parameters
|
|
----------
|
|
background : SpectralQty
|
|
The received background radiation
|
|
signal : SpectralQty
|
|
The received signal radiation
|
|
obstruction : float
|
|
The obstruction factor of the aperture as ratio A_ob / A_ap
|
|
|
|
Returns
|
|
-------
|
|
signal_current : Quantity
|
|
The electron current on the detector caused by the target in electrons / s.
|
|
size : str
|
|
The size of the target.
|
|
obstruction : float
|
|
The obstruction factor as A_ob / A_ap.
|
|
background_current : Quantity
|
|
The electron current on the detector caused by the background in electrons / (s * pix).
|
|
"""
|
|
# Calculate the photon current of the background
|
|
logger.info("Calculating the background photon current.")
|
|
background_photon_current = background * np.pi * (
|
|
self.__pixel_size.to(u.m) ** 2 / u.pix) / (4 * self.__f_number ** 2 + 1) * (1 * u.sr)
|
|
# Calculate the incoming photon current of the target
|
|
logger.info("Calculating the signal photon current.")
|
|
size = "extended" if signal.qty.unit.is_equivalent(u.W / (u.m ** 2 * u.nm * u.sr)) else "point"
|
|
if size == "point":
|
|
signal_photon_current = signal * np.pi * (self.__common_conf.d_aperture() / 2) ** 2
|
|
else:
|
|
signal_photon_current = signal * np.pi * self.__pixel_size.to(u.m) ** 2 / (
|
|
4 * self.__f_number ** 2 + 1) * (1 * u.sr)
|
|
# Calculate the electron current of the background and thereby handling the photon energy as lambda-function
|
|
background_current = (
|
|
background_photon_current / (lambda wl: (const.h * const.c / wl).to(u.W * u.s) / u.photon) *
|
|
self.__quantum_efficiency).integrate().decompose()
|
|
# Calculate the electron current of the signal and thereby handling the photon energy as lambda-function
|
|
signal_current = (signal_photon_current / (lambda wl: (const.h * const.c / wl).to(u.W * u.s) / u.photon) *
|
|
self.__quantum_efficiency).integrate().decompose()
|
|
logger.debug("Signal current: %1.2e e-/s" % signal_current.value)
|
|
logger.debug("Target size: " + size)
|
|
logger.debug("Obstruction: %.2f" % obstruction)
|
|
logger.debug("Background current: %1.2e e-/s" % background_current.value)
|
|
return signal_current, size, obstruction, background_current
|
|
|
|
@staticmethod
|
|
def check_config(sensor: Entry, conf: Entry) -> Union[None, str]:
|
|
"""
|
|
Check the configuration for this class
|
|
|
|
Parameters
|
|
----------
|
|
sensor : Entry
|
|
The configuration entry to be checked.
|
|
conf: Entry
|
|
The complete configuration.
|
|
|
|
Returns
|
|
-------
|
|
mes : Union[None, str]
|
|
The error message of the check. This will be None if the check was successful.
|
|
"""
|
|
if not hasattr(sensor, "f_number"):
|
|
return "Missing container 'f_number'."
|
|
mes = sensor.f_number.check_float("val")
|
|
if mes is not None:
|
|
return "f_number: " + mes
|
|
if not hasattr(sensor, "pixel_geometry"):
|
|
return "Missing container 'pixel_geometry'."
|
|
mes = sensor.pixel_geometry.check_quantity("val", u.pix)
|
|
if mes is not None:
|
|
return "pixel_geometry: " + mes
|
|
if hasattr(sensor, "center_offset") and isinstance(sensor.center_offset, Entry):
|
|
mes = sensor.center_offset.check_quantity("val", u.pix)
|
|
if mes is not None:
|
|
return "center_offset: " + mes
|
|
|
|
# Check pixel
|
|
if not hasattr(sensor, "pixel"):
|
|
return "Missing container 'pixel'."
|
|
if not hasattr(sensor.pixel, "quantum_efficiency"):
|
|
return "Missing container 'quantum_efficiency'."
|
|
mes = sensor.pixel.quantum_efficiency.check_quantity("val", u.electron / u.photon)
|
|
if mes is not None:
|
|
mes = sensor.pixel.quantum_efficiency.check_file("val")
|
|
if mes is not None:
|
|
return "pixel -> quantum_efficiency: " + mes
|
|
if not hasattr(sensor.pixel, "pixel_size"):
|
|
return "Missing container 'pixel_size'."
|
|
mes = sensor.pixel.pixel_size.check_quantity("val", u.m)
|
|
if mes is not None:
|
|
return "pixel -> pixel_size: " + mes
|
|
if not hasattr(sensor.pixel, "dark_current"):
|
|
return "Missing container 'dark_current'."
|
|
mes = sensor.pixel.dark_current.check_quantity("val", u.electron / (u.pix * u.s))
|
|
if mes is not None:
|
|
return "pixel -> dark_current: " + mes
|
|
if not hasattr(sensor.pixel, "sigma_read_out"):
|
|
return "Missing container 'sigma_read_out'."
|
|
mes = sensor.pixel.sigma_read_out.check_quantity("val", u.electron ** 0.5 / u.pix)
|
|
if mes is not None:
|
|
return "pixel -> sigma_read_out: " + mes
|
|
if not hasattr(sensor.pixel, "well_capacity"):
|
|
return "Missing container 'well_capacity'."
|
|
mes = sensor.pixel.well_capacity.check_quantity("val", u.electron)
|
|
if mes is not None:
|
|
return "pixel -> well_capacity: " + mes
|
|
|
|
# Check photometric aperture
|
|
if not hasattr(sensor, "photometric_aperture"):
|
|
setattr(sensor, "photometric_aperture", Entry(shape=Entry(val="circle"),
|
|
contained_energy=Entry(val="FWHM")))
|
|
if not hasattr(sensor.photometric_aperture, "shape"):
|
|
return "Missing container 'shape'."
|
|
mes = sensor.photometric_aperture.shape.check_selection("val", ["square", "circle"])
|
|
if mes is not None:
|
|
return "photometric_aperture -> shape: " + mes
|
|
if hasattr(sensor.photometric_aperture, "aperture_size"):
|
|
mes = sensor.photometric_aperture.aperture_size.check_quantity("val", u.pix)
|
|
if mes is not None:
|
|
return "photometric_aperture -> aperture_size: " + mes
|
|
else:
|
|
if not hasattr(sensor.photometric_aperture, "contained_energy"):
|
|
return "Missing container 'contained_energy'."
|
|
mes = sensor.photometric_aperture.contained_energy.check_float("val")
|
|
if mes is not None:
|
|
if conf.common.psf.type.lower() == "airy":
|
|
mes = sensor.photometric_aperture.contained_energy.check_selection("val",
|
|
["peak", "FWHM", "fwhm",
|
|
"min"])
|
|
if mes is not None:
|
|
return "photometric_aperture -> contained_energy: " + mes
|
|
else:
|
|
mes = sensor.photometric_aperture.contained_energy.check_selection("val", ["FWHM", "fwhm"])
|
|
if mes is not None:
|
|
return "photometric_aperture -> contained_energy: " + mes
|