SkyImages

class SkyImages(sky_count, sky_var, src_subimage_size, exposure, time_exp_mn, attitude)

Bases: object

build and save computed sky images

constructor

exposure = deconvolution_module.remove_padding_from_sky(deconvolution_module.A) * time_exp_mn * 60

3 group of sky images:

• initial_sky : set by the constructor
• cleaned_sky : initial_sky cleaned by a source model, keeping the source
• remains_sky : initial_sky entirely cleaned by a source model

Parameters:

• sky_count (2D array) – a deconvolved sky array
• sky_var (2D array) – a deconvolved variance sky array
• src_subimage_size (int) – nb of pixels around the detected source (radius) kept in the final sky image
• exposure (2D array) – exposure from the deconvolution of sky_count
• time_exp_mn (float) – observation time in min
• attitude ([float, float, float]) – [ra, dec, ori] in degrees

Methods Summary

arf_correction(dpix, energy_range)	apply the arf correction on the sky count image
build_wcs(attitude)	build the wcs object from the attitude
compute_snr(sky_count, sky_var)	compute snr image from sky_count and sky_var
cos_theta_correction([instru_eclairs])	apply off axis corrections on the sky images
irf_correction(dpix)	apply the irf correction matrix on the sky count image
remove_src_model(model_shadowgram, …)	substract the src model from the sky
sin_theta(image, instru_eclairs)	return the sin theta image

Methods Documentation

arf_correction(dpix, energy_range)

apply the arf correction on the sky count image

Parameters:

• dpix (ECLAIRsDetectorEffectDefault) – instrument effects
• energy_range ([int, int]) – energy range (in PI) [low_energy, high_energy]

build_wcs(attitude)

build the wcs object from the attitude

Parameters:attitude ([float, float, float]) – [ra, dec, ori] in degrees Returns:wcs object from attitude Return type:astropy.wcs.WCS

compute_snr(sky_count, sky_var)

compute snr image from sky_count and sky_var

sky_snr cleaned of <1E-9 values in sky_var

Parameters:

• sky_count (2D array) – sky image
• sky_var (2D array) – sky variance image

Returns:

sky_snr

Return type:

2D array

cos_theta_correction(instru_eclairs=<common.instru.model_geom.InstruECLAIRs object>)

apply off axis corrections on the sky images

Parameters:instru_eclairs (InstruECLAIRs) – ECLAIRs instrument

irf_correction(dpix)

apply the irf correction matrix on the sky count image

Parameters:dpix (ECLAIRsDetectorEffectDefault) – instrument effects

remove_src_model(model_shadowgram, model_count, model_var, model_pos, model_name)

substract the src model from the sky

build new cleaned sky images and new remains sky images

add the source model image and name at self.models

model_count, model_var = src image model_pos = [pix_x, pix_y] src position

Parameters:

• model_shadowgram (2D array) – shadowgrams of the source model
• model_count (2D array) – sky image of the source
• model_var (2D array) – sky variance image of the source
• model_pos (['', int, int]) – position of the source in the sky image [‘’, pix_x, pix_y]
• model_name (string) – name of the source

sin_theta(image, instru_eclairs)

return the sin theta image

Parameters:

• image (2d-array) – sky image to be corrected
• instru_eclairs (InstruECLAIRs) – ECLAIRs instrument

Returns:

sin theta image (same shape as image)

Return type:

2d array