New Short-Period δ Scuti Stars in OGLE-IV Fields toward
the Galactic Bulge
P. Pietrukowicz1, M. Ratajczak1, I. Soszyński1,
A. Udalski1, M.K. Szymański1, K. Ulaczyk2,
R. Poleski1, S. Kozłowski1, J. Skowron1,
D.M. Skowron1, P. Mróz1, K. Rybicki1,3, P. Iwanek1,
M. Wrona1, and M. Gromadzki1
1Astronomical Observatory, University of Warsaw, Al. Ujazdowskie 4, 00-478 Warszawa, Poland
2Department of Physics, University of Warwick, Coventry CV4 7AL, UK
3Department of Particle Physics and Astrophysics, Weizmann Institute of
Science, Rehovot 76100, Israel
Received: November 7, 2022
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 min and 54 min whose type could not have been unambiguously
established based on photometry only. A low-resolution spectroscopic
follow-up observations have shown that all the objects are main sequence A/F-type
stars. Thus, all the variables are δ Sct-type pulsators. We have
added them to the OGLE-IV Collection of Variable Stars.
Key words:
Catalogs - Stars: variables: delta Scuti - Galaxy: bulge - Galaxy: disk
Full article text (PDF)
back
