Detection of Variable Stars in the Open Cluster M11 Using Difference Image Analysis Pipeline

Abstract

We developed a photometric pipeline to be used for a wide field survey. This pipeline employs the difference image analysis (DIA) method appropriate for the photometry of star dense field such as the Galactic bulge. To verify the performance of pipeline, the observed dataset of the open cluster M11 was re-processed. One hundred seventy eight variable stars were newly discovered by analyzing the light curves of which photometric accuracy was improved through the DIA. The total number of variable stars in the M11 observation region is 335, including 157 variable stars discovered by previous studies. We present the catalogue and light curves for the 178 variable stars. This study shows that the photometric pipeline using the DIA is very useful in the detection of variable stars in a cluster.

The Detached Eclipsing Binary Kv 29 and the Age of the Open Cluster M11

“…The photometry of the secondary star in the eclipsing binary appears to put it in the instability strip where it crosses the main sequence. This part of the instability strip is inhabited by δ Scuti and γ Doradus pulsating stars, and more than a dozen δ Sct stars have previously been detected via their photometric variability (Hargis et al 2005;Koo et al 2007;Lee et al 2010). Seven δ Sct are likely cluster members according to proper motions (McNamara et al 1977), but these are likely to be just the stars with the highest pulsation amplitudes.…”

Testing Accuracy and Precision of Existing Photometry Algorithms on Moving Targets

“…Becker et al (2007) find that the Photo software used on the Sloan Digital Sky Survey performs high-quality photometry on both extended sources and field stars, but it is not portable or flexible and was thus not available to install. Three other prominent photometry packages, ISIS, MOMF, and DIA, could not be modified for use on data for a moving target, though they did offer promising improvements to our photometry results (Kjeldsen and Frandsen 1992;Alard 2000;Wozniak 2000;Lee et al 2010). These packages all perform photometry on fixed objects in median-sky subtracted images, identifying low-level deviations from the nightly median.…”

DEVELOPMENT OF REAL-TIME DATA REDUCTION PIPELINE FOR KMTNet

“…각각의 망원경은 미국 임시관측소에서 조립과 성능시험 을 거친 후 현지에 설치되며, 현재 시험 중인 망원경은 2013년 초에 칠레에 설치된다 (Kappler et al, 2012;Poteet et al, 2012). Lee et al, 2010Lee et al, , 2012 …”