Detector#

class m4opt.synphot.Detector(plate_scale, area, bandpasses, background, dark_noise=<Quantity 0. Hz>, read_noise=0.0, npix=12.566370614359172, aperture_correction=1.0, gain=1.0)[source] [edit on github]#

Bases: object

Sensitivity calculator: compute SNR for exposure time or vice-versa.

Attributes Summary

`aperture_correction`	Fraction of the signal from a point source in the photometry aperture.
`area`	Effective collecting area.
`background`	Background 1D model mapping wavelength to surface brightness.
`bandpasses`	Dictionary of 1D models mapping wavelength to dimensionless transmission.
`dark_noise`	Dark noise count rate.
`gain`	Detector gain.
`npix`	Effective number of pixels in the photometry aperture.
`plate_scale`	Solid angle per pixel.
`read_noise`	Number of noise counts due to readout.

Methods Summary

`get_exptime`(snr, source_spectrum[, bandpass])
`get_limmag`(snr, exptime, source_spectrum[, ...])	Get the limiting magnitude for a given SNR and exposure time.
`get_snr`(exptime, source_spectrum[, bandpass])

Attributes Documentation

Parameters:

plate_scale (PhysicalType('solid angle'))
area (Annotated[Quantity, PhysicalType('area')])
bandpasses (dict[Hashable, Model])
background (SourceSpectrum)
dark_noise (Annotated[Quantity, PhysicalType('frequency')])
read_noise (float)
npix (float)
aperture_correction (float)
gain (float)

aperture_correction: float = 1.0#

Fraction of the signal from a point source in the photometry aperture.

The default value of 1 is appropriate for PSF photometry.

area: Annotated[Quantity, PhysicalType('area')] = <dataclasses._MISSING_TYPE object>#: Effective collecting area.

background: SourceSpectrum = <dataclasses._MISSING_TYPE object>#: Background 1D model mapping wavelength to surface brightness.

bandpasses: dict[Hashable, Model] = <dataclasses._MISSING_TYPE object>#: Dictionary of 1D models mapping wavelength to dimensionless transmission.

dark_noise: Annotated[Quantity, PhysicalType('frequency')] = <Quantity 0. Hz>#: Dark noise count rate.

gain: float = 1.0#: Detector gain.

npix: float = 12.566370614359172#

Effective number of pixels in the photometry aperture.

The default value of 4π is appropriate for a PSF that is critically sampled by the pixels [1].

References

plate_scale: PhysicalType('solid angle') = <dataclasses._MISSING_TYPE object>#: Solid angle per pixel.

read_noise: float = 0.0#: Number of noise counts due to readout.

Methods Documentation

get_exptime(snr, source_spectrum, bandpass=None)[source] [edit on github]#

Parameters:

snr (float)
source_spectrum (Model)
bandpass (Hashable | None)

get_limmag(snr, exptime, source_spectrum, bandpass=None)[source] [edit on github]#

Get the limiting magnitude for a given SNR and exposure time.

Note that the limiting magnitude is relative to the source spectrum, so you should pass a source spectrum that has an apparent magnitude of 0.

Parameters:

snr (float)
exptime (Annotated[Quantity, PhysicalType('time')])
source_spectrum (Model)
bandpass (Hashable | None)

get_snr(exptime, source_spectrum, bandpass=None)[source] [edit on github]#

Parameters:

exptime (Annotated[Quantity, PhysicalType('time')])
source_spectrum (Model)
bandpass (Hashable | None)