A search for long period variables in the SMC

Abstract

ABSTRACT. A search for long period variables in the Small Magellanic Cloud (SMC) was made using I plates from the U.K. Schmidt telescope. Variables were identified using a blink comparator built specially for this project and plates were digitised to determine periods and light curves for suspected variables. Over 300 new variables with periods in excess of 100 days were found, some variables having periods in excess of 1000 days.

A search for long period variables in the SMC

“…Also on screen are the coordinates, allowing rapid comparison with finding charts. Photometry can also be performed on the screen as described by Moore and Ihnat (1984). Film copies mounted in glass are used to permit photographic background equalisation before blinking and to reduce the plates to the more manageable size of 120 mm 2 .…”