An automated approach for photometry and dust mass calculation of the Crab nebula

Ample evidence exists regarding supernovae being a major contributor to interstellar dust. In this work, the deepest far-infrared observations of the Crab Nebula are used to revisit the estimation of} the dust mass present in this supernova remnant. Images in filters between 70 and 500 $\mu$m taken by the PACS and SPIRE instruments on-board of the Herschel Space Observatory are used. With an automated approach we constructed the spectral energy distribution of the Crab nebula to recover the dust mass. This approach makes use of several image processing techniques (thresholding, morphological processes, contouring, etc..) to objectively separate the nebula from its surrounding background. After subtracting the non-thermal synchrotron component from the integrated fluxes, the spectral energy distribution is found to be best fitted using a single modified blackbody of temperature $T=42.06\pm1.14$ K and a dust mass of $M_{d}=0.056\pm0.037$ M$_{\odot}$. In this paper, we show the importance of the photometric analysis and spectral energy distribution construction in the inference of the dust mass of the Crab nebula.