PHANGS-ALMA arcsecond CO(2-1) imaging of galaxies : J/ApJS/257/43

PHANGS-ALMA is a key component of the multiwavelength observational campaign conducted by the Physics at High Angular resolution in Nearby Galaxies (PHANGS) project. Combining a Cycle 5 ALMA Large Program (PI: E. Schinnerer), a suite of smaller programs, and data from the ALMA archive, PHANGS-ALMA mapped the CO J=2->1 emission, hereafter CO(2-1), from a cleanly selected sample of 90 of the nearest, ALMA-accessible, massive, star-forming galaxies. We used the ALMA main array of 12m dishes in a compact configuration, which yields ~1" resolution at Band 6 ({nu}~230GHz), corresponding to ~100 pc linear resolution, or about the size of a massive giant molecular cloud at the typical distance to our targets. We covered the area of active star formation in each target using large mosaics that consisted of ~100-450 12m pointings per galaxy. Including all pilots and extensions, observations for PHANGS-ALMA spanned six years, from early 2013 until the end of