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arXiv · 2212.07355

New Short-Period Delta Scuti Stars in OGLE-IV Fields toward the Galactic Bulge

P. Pietrukowicz·M. Ratajczak·I. Soszynski·A. Udalski·M. K. Szymanski·K. Ulaczyk·R. Poleski·S. Kozlowski·J. Skowron·D. M. Skowron·P. Mroz·K. Rybicki·P. Iwanek·M. Wrona·M. Gromadzki
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Abstract

We report the classification of 24 puzzling short-period variable stars located in OGLE-IV Galactic bulge fields. The stars are low-amplitude (<0.05 mag) multi-periodic objects with dominant periods between 22 and 54 min whose type could not have been unambiguously established based on photometry only. A low-resolution spectroscopic follow-up has shown that all the objects are main sequence A/F-type stars. Thus, all the variables are delta Sct-type pulsators. We have added them to the OGLE-IV Collection of Variable Stars.

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P. Pietrukowicz, M. Ratajczak, I. Soszynski, A. Udalski, M. K. Szymanski, K. Ulaczyk, R. Poleski, S. Kozlowski, J. Skowron, D. M. Skowron, P. Mroz, K. Rybicki, P. Iwanek, M. Wrona, M. Gromadzki. 2022-12-14. New Short-Period Delta Scuti Stars in OGLE-IV Fields toward the Galactic Bulge. https://doi.org/10.32023/0001-5237/72.3.1

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