@Article{BragaCMFCMNZ:2019:NeTyII,
author = "Braga, Vittorio F. and Contreras Ramos, R. and Minniti, Dante and
Ferreira Lopes, Carlos Eduardo and Catelan, M{\'a}rcio and
Minniti, J. H. and Nikzat, F. and Zoccali, M.",
affiliation = "{Instituto Milenio de Astrof{\'{\i}}sica} and {Instituto Milenio
de Astrof{\'{\i}}sica} and {Instituto Milenio de
Astrof{\'{\i}}sica} and {Instituto Nacional de Pesquisas
Espaciais (INPE)} and {Instituto Milenio de Astrof{\'{\i}}sica}
and {Instituto Milenio de Astrof{\'{\i}}sica} and {Instituto
Milenio de Astrof{\'{\i}}sica} and {Instituto Milenio de
Astrof{\'{\i}}sica}",
title = "New type II cepheids from VVV data towards the galactic center",
journal = "Astronomy \& Astrophysics",
year = "2019",
volume = "625",
pages = "A151",
month = "May",
keywords = "stars: variables: Cepheids / Galaxy: bulge / Galaxy: center.",
abstract = "Context. The Galactic center (GC) is the densest region of the
Milky Way. Variability surveys towards the GC potentially provide
the largest number of variable stars per square degree within the
Galaxy. However, high stellar density is also a drawback due to
blending. Moreover, the GC is affected by extreme reddening,
therefore near infrared observations are needed. Aims. We plan to
detect new variable stars towards the GC, focusing on type II
Cepheids (T2Cs) which have the advantage of being brighter than RR
Lyrae stars. Methods. We perform parallel Lomb-Scargle and
Generalized Lomb-Scargle periodogram analysis of the Ks-band time
series of the VISTA variables in the V{\'{\i}}a L{\'a}ctea
survey, to detect periodicities. We employ statistical parameters
to clean our sample. We take account of periods, light amplitudes,
distances, and proper motions to provide a classification of the
candidate variables. Results. We detected 1019 periodic variable
stars, of which 164 are T2Cs, 210 are Miras and 3 are classical
Cepheids. We also found the first anomalous Cepheid in this
region. We compare their photometric properties with overlapping
catalogs and discuss their properties on the color-magnitude and
Bailey diagrams. Conclusions. We present the most extensive
catalog of T2Cs in the GC region to date. Offsets in
E(J\ \−\ Ks) and in the reddening law cause
very large (\∼12 kpc) uncertainties on distances in this
region. We provide a catalog which will be the starting point for
future spectroscopic surveys in the innermost regions of the
Galaxy.",
doi = "10.1051/0004-6361/201935103",
url = "http://dx.doi.org/10.1051/0004-6361/201935103",
issn = "0004-6361 and 1432-0746",
label = "lattes: 4656875806985353 4 BragaCMFCMNZ:2019:NeTyII",
language = "en",
targetfile = "aa35103-19.pdf",
urlaccessdate = "28 abr. 2024"
}