ALMACAL

ALMACAL is a survey to discover galaxies within images produced during Atacama Large Millimeter Array (ALMA) calibration observations. Like those of basically any research telescope, ALMA observations must be calibrated by comparing the observation-of-interest with those of known sources, generally near-in-time so as to calibrate short-term effects, such as atmospheric effects and the response of the instrument (which varies by the instrument's age, temperature, etc.), resulting in many such calibration observations. Like a slew survey, ALMACAL makes serendipitous use of data collected other than that of observations of the targets, and through this data, a wide survey is achieved even though ALMA's purpose is producing fine detail within a small field of view, and wide surveys are generally prohibitive for requiring too much of its limited time. Calibrations of the same calibration targets (calibrators) are repeated as they are generally from an established catalog of sources for the purpose. Thus data from multiple calibrations of the same field can be used to acquire integration time for this survey. The galaxies are detected through methods developed for other surveys of distant galaxies, such as determining their effects on EMR from background sources such as quasars.