@article{e3a344f17cef4f5b9e8f4db7004b5665,
title = "EMCCD photometry reveals two new variable stars in the crowded central region of the globular cluster NGC 6981",
abstract = "Two previously unknown variable stars in the crowded central region of the globular cluster NGC 6981 are presented. The observations were made using the electron multiplying CCD (EMCCD) camera at the Danish 1.54 m Telescope at La Silla, Chile. The two variables were not previously detected by conventional CCD imaging because of their proximity to a bright star. This discovery demonstrates that EMCCDs are a powerful tool for performing high-precision time-series photometry in crowded fields and near bright stars, especially when combined with difference image analysis.",
keywords = "Globular clusters: individual: NGC 6981, Stars: variables: RR Lyrae, Instrumentation: high angular resolution, Stars: variables: general",
author = "J. Skottfelt and Bramich, {D. M.} and {Figuera Jaimes}, {Roberto Jose} and Jorgensen, {U. G.} and No{\'e} Kains and Harpsoe, {K. B. W.} and C. Liebig and Penny, {M. T.} and Alsubai, {K. A.} and Andersen, {J. M.} and V. Bozza and P. Browne and {Calchi Novati}, S. and Y. Damerdji and C. Diehl and M. Dominik and A. Elyiv and E. Giannini and F. Hessman and Hinse, {T. C.} and M. Hundertmark and D. Juncher and E. Kerins and H. Korhonen and L. Mancini and R. Martin and M. Rabus and S. Rahvar and G. Scarpetta and J. Southworth and C. Snodgrass and Street, {R. A.} and J. Surdej and J. Tregloan-Reed and C. Vilela and A. Williams",
note = "J.S. acknowledges support from the ESO 2012 DGDF for a two month visit to ESO Garching. The operation of the Danish 1.54 m telescope is financed by a grant to UGJ from the Danish Natural Science Research Council. We also acknowledge support from the European Community{\textquoteright}s Seventh Framework Programme (FP7/2007−2013/) under grant agreement Nos. 229517, 268421 and 274889 and from the Center of Excellence Centre for Star and Planet Formation (StarPlan) funded by The Danish National Research Foundation. K.A.A., M.D., D.M.B., C.L., M.H., R.A.S. and C.S. are thankful to Qatar National Research Fund (QNRF), member of Qatar Foundation, for support by grant NPRP 09-476-1-078. Y.D., A.E. under J.S. acknowledge support from the Communaut{\'e} fran{\c c}aise de Belgique – Actions de recherche concert{\'e}es – Acad{\'e}mie universitaire to Wallonie-Europe. TCH acknowledges support from the Korea Research Council of Fundamental Science & Technology (KRCF) via the KRCF Young Scientist Research Fellowship Programme and for financial support from KASI travel grant number 2013-9-400-00. M.R. acknowledges support from FONDECYT postdoctoral fellowship No. 3120097.",
year = "2013",
month = may,
doi = "10.1051/0004-6361/201321430",
language = "English",
volume = "553",
journal = "Astronomy & Astrophysics",
issn = "0004-6361",
publisher = "EDP SCIENCES S A",
}