the first candidate for a galaxy cluster discovered in the

RevMexAA (Serie de Conferencias), 00, 1–1 (2007)
ABSTRACT ONLY
VVV-J144321.0-611753.9: THE FIRST
CANDIDATE FOR A GALAXY CLUSTER
DISCOVERED IN THE VISTA VARIABLES IN
THE VIA LACTEA SURVEY
J. L. Nilo Castellón1,2 , M. V. Alonso3,4 , L.
Baravalle3 C. Valotto3,4 , R. Barbá1 . D. Minniti5
This abstract summarizes our mural contribution to
the conference.
The structure of the Milky Way has been the
main obstacle in the study of the Large Scale of
the Universe (LSS). This has been a major problem
over the years, since the mapping of the extragalactic sources located behind the bulge and the disk of
the galaxy, is essential to determine the extension of
the structures located behind the MW, which define
among others, the dynamic of our Local Group.
The Search for Extragalactic Sources in the
VISTA Variables in the Via Lactea Survey (Baravalle
et al. 2015, in prep), is the first systematic program
devoted to search for extragalactic sources obscured
by the bulge and the plane of the Milky Way, in the
area covered by the VVV survey. The main goal of
the project, is to look for galaxies, quasars, blazars
and galaxy clusters located behind the galaxy structure, in order to contributing in the mapping of the
Large Scale Structure
The program take advantage of the high resolution images provided by the VVV survey, and the
latest versions of the AtrOmatic pipelines, to reprocessed the images and create full catalogs based
on Point-Spread Function (PSF) fitting photometry,
in order to obtain a series of morphological parameters, astrometrical values, and photometric properties of each source detected.
We report the discovery of SESVVV-001 (VVV
J144321.0-611753.9), the first concentration of galaxies classified as the first galaxy cluster candidate detected using only data provided by the VVV survey. VVVSES-001 is located at α=14h 43m 20.9s δ=61◦ 17m 53.6s , and is composed by 25 galaxies (at
least), all of them with magnitudes ranging between
14 < Ks < 17. The Color-Magnitude Diagram shows
a clear trend of galaxies at (J - K)∼1.8, with an slope
of s=-0.0453 and a zero-point of zp=2.5001 for the
best lineal fit. A population of blue galaxies bellow
3σ the best lineal fit is also observed, with a similar distribution to the called blue cloud of galaxies.
Comparing the (J - K) color of the most brightest
galaxy(BCG) and the slope of the RCS with Bruzual
& Charlot (2003) models and semi-analytical models
extracted from Bower et al. (2006) locate VVVSES001 at z∼0.434. X-ray emission extracted from the
ROSAT All Sky Survey indicate that the core of
VVVSES-001 is clearly detected in X-rays emission,
with the cluster core about 1 arcmin in the north
direction of the X-ray peak emission.
1
Departamento de Fı́sica y Astronomı́a, Universidad de La
Serena, Avenida Juan Cisternas 1200, La Serena, Chile. (jnilo
@userena.cl)
2 Dirección de Investigación.
Universidad de La Serena.
Avenida Raul Bitran s/n, La Serena, Chile.
3 Instituto de Astronoma Teórica y Experimental (IATECONICET). Laprida 922, Córdoba, Argentina.
4 Observatorio Astronómico,
Universidad Nacional de
Córdoba (OAC-UNC), Laprida 854, Córdoba, Argentina.
5 Observatorio Astronómico,
Universidad Nacional de
Córdoba (OAC-UNC), Laprida 854, Córdoba, Argentina.
1