English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

The Galactic center (GC) is the densest region of the Milky Way. Variabilitysurveys towards the GC potentially provide the largest number of variable starsper square degree within the Galaxy. However, high stellar density is also adrawback due to blending. Moreover, the GC is affected by extreme reddening,therefore near infrared observations are needed. We plan to detect new variablestars towards the GC, focusing on type II Cepheids (T2Cs) which have theadvantage of being brighter than RR Lyrae stars. We perform parallelLomb-Scargle and Generalized Lomb-Scargle periodogram analysis of the$K_s$-band time series of the VISTA variables in the Via Lactea survey, todetect periodicities. We employ statistical parameters to clean our sample. Wetake account of periods, light amplitudes, distances, and proper motions toprovide a classification of the candidate variables. We detected 1,019 periodicvariable stars, of which 164 are T2Cs, 210 are Miras and 3 are classicalCepheids. We also found the first anomalous Cepheid in this region. We comparetheir photometric properties with overlapping catalogs and discuss theirproperties on the color-magnitude and Bailey diagrams. We present the mostextensive catalog of T2Cs in the GC region to date. Offsets in E($J-K_s$) andin the reddening law cause very large ($\sim$1-2 kpc) uncertainties ondistances in this region. We provide a catalog which will be the starting pointfor future spectroscopic surveys in the innermost regions of the Galaxy.

New type II Cepheids from VVV data towards the Galactic center