Cataloguing Variable Sources and IFU-like Science with Multiband Surveys.

Abstract

The Southern Photometric Local Universe Survey (SPLUS) aims to map 8000 squared degrees of the Southern sky with twelve optical bands using a new dedicated 0.8m robotic telescope at Cerro Tololo, T80South, and a widefield optical imager. In the first data release (DR1) of SPLUS, images and catalogues for 160 squared degrees for the region of the SDSS STRIPE82 were made available. The project described below involves studies to be performed with DR1 data and internal collaboration data on the Hydra cluster and later to be extended to the whole surveys SPLUS and JPAS. The postdoc will have two main tasks: 1) create a catalogue of all known variable stars in DR1 and study their properties through the twelve SPLUS photometric bands combined with literature data~ 2) do the characterization of stellar populations for all galaxies present in DR1 brighter than r=18. The first will allow us to characterize the spectral properties of hundreds of variable stars of yet unknown type, specially those whose variable fluxes are strongly related to the intrinsic physical properties of the sources. The postdoc will develop tools to detect variables with periods ranging from 30s to 100 min. The second subproject has the goal of determining ages, metallicities and abundances for galaxies is the STRIPE82 using different methods. In both cases the ultimate goal isto also produce tools for the JPAS survey, which will cover 8000 square degrees in 59 narrowbands down to i=22.5.Modern astronomy has entered a new era of massive data acquisition. The current and new generation of photometric redshift surveys such as SDSS, PanSTARRS , DES, LSST or JPAS (among others), will provide multicolour information for millions of galaxies, enabling precise cosmological studies at different cosmic epochs. In this context, a huge effort (a partnership between FAPESP and several other institutions) led to the construction of a robotic telescope called T80South to survey 8000 square degrees of the southern sky in 12 bands. The goal of this proposal is to exploit such data. DR1 covers 160 squared degrees inside STRIPE82, a region of SDSS exploited by a number of studies, in different wavelengths. This dataset works as a cross calibration baseline among different projects.T80South is a RitcheyChretien 80cm robotic telescope on Cerro Tololo, equipped with a large format CCD camera (2 deg2 field with 0.55 arcsec pixels), which is performing SPLUS (www.splus.iag.usp.br/en) in the next four years. SPLUS will cover 8000 sq degrees mostly of the southern hemisphere, to a depth similar to the Sloan Digital Sky Survey, in 12 bands (5 Sloanlike bands and 7 narrowband filters centred on prominent stellar features). The T80South telescope was installed at CTIO in October/2014, and its widefield camera (2 deg2 ) was installed in November/2015.T80South started regular operations in August 2017. SPLUS has been designed to find lowmetallicity and bluehorizontal branch stars, highz quasars, determine the physical properties of nearby galaxies and to map the largescale structure in the nearby universe.