Background

The imUtil.properSub package contains basic function for proper image subtraction (Zacky, Ofek, and Gal-Yam 2016; hereafter ZOGY).

The tools implement the basic ZOGY routines as well as the Translient algorithm (in prep.). More information, as well as a description of the high-level class for image subtraction, is available in the AstroZOGY class page.

A common feature of almost all functions is that they can work on cube image inputs, in which the image index is in the 3rd dimension. In this case, the output will be calculated for each image in the cube.

List of functions

• imUtil.properSub.allFunList - Functions and Classes list for the imUtil.properSub package

ZOGY subtraction:

• imUtil.properSub.subtractionScorr - Return the S_corr, S, D subtraction images (proper subtraction)
• imUtil.properSub.subtractionS - Return the S_hat and D_hat subtraction images (Fourier transform of proper subtraction)
• imUtil.properSub.subtractionD - Return the D_hat subtraction image (Fourier transform of proper subtraction)
• imUtil.properSub.subtraction - OBSOLETE - Proper image subtraction between two images (D, Pd, S, S_corr).

ZOGY utilities and low-level functions:

• imUtil.properSub.astrometricNoise - Calculate the subtraction astrometric noise variance based on kr_hat, kn_hat
• imUtil.properSub.knkr - Calculate the subtraction kr_hat and kn_hat
• imUtil.properSub.sourceNoise - Calculate the subtraction source noise variance based on kr_hat, kn_hat
• imUtil.properSub.subtractionDnDr - The partial proper image subtraction between two images.
• imUtil.properSub.subtractionFluxS - Calculate the proper subtraction flux normalization factor (F_S)

Traslient-related routines:

• imUtil.properSub.translient - Image substruction for detection of point source motion using the
• imUtil.properSub.translientAuxiliary - Normalization of the TRANSLIENT score image.
• imUtil.properSub.translientMCMC - MCMC simulations to retrieve the flux and displacement parameters.
• imUtil.properSub.translientROC - Generate ROC curve for a given set of parameters with simulations. The SNR is determined

imUtil.properSub.subtractionScorr

The highest level ZOGY function is imUtil.properSub.subtractionScorr. This function calculates all the ZOGY data products.

[Scorr, S, D, Pd, Fd, D_den, D_num, D_denSqrt, SdeltaN, SdeltaR] = imUtil.properSub.subtractionScorr(rand(25,25), rand(25,25), rand(25,25), rand(25,25), 1, 1, 1, 1)