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arXiv · 1903.07611

Total Power Map to Visibilities (TP2VIS): Joint Deconvolution of ALMA 12m, 7m, and Total Power Array Data

Jin Koda·Peter Teuben·Tsuyoshi Sawada·Adele Plunkett·Ed Fomalont
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Abstract

We present a new package for joint deconvolution of ALMA 12m, 7m, and Total Power (TP) data, dubbed ``Total Power Map to Visibilities (TP2VIS)". It converts a TP (single-dish) map into visibilities on the CASA platform, which can be input into deconvolvers (e.g., CLEAN) along with 12m and 7m visibilities. A manual is presented in the Github repository (https://github.com/tp2vis/distribute). Combining data from the different ALMA arrays is a driver for a number of science topics, namely those that probe size scales of extended and compact structures simultaneously. We test TP2VIS using model images, one with a single Gaussian and another that mimics the internal structures of giant molecular clouds. The result shows that the better uv coverage with TP2VIS visibilities helps the deconvolution process and reproduces the model image within errors of only 5% over two orders of magnitude in flux.

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Jin Koda, Peter Teuben, Tsuyoshi Sawada, Adele Plunkett, Ed Fomalont. 2019-03-18. Total Power Map to Visibilities (TP2VIS): Joint Deconvolution of ALMA 12m, 7m, and Total Power Array Data. https://doi.org/10.1088/1538-3873%2Fab047e

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