ASTROMETRIA, PREDIÇÃO DE OCULTAÇÕES ESTELARES E EXPLORAÇÃO DE DADOS FOTOMÉTRICOS DO DES PARA TNOS E CENTAUROS EM PREPARAÇÃO AO LSST.

Abstract

The Dark Energy Survey (DES) is an international collaborative effort to reveal the nature of the mysterious dark energy which is responsible for the accelerated expansion of the universe. For this, the survey mapped about 5.000 square degrees of the southern hemisphere sky over 6 years (2013-2019) and on 5 optical filters. Among the hundreds of millions of galaxies observed, DES priority targets, more than 100.000 solar system objects have been observed. Thus, DES is also an astrometric and photometric treasure for the study of small bodies, and its exploration motivates the development of tools for working with big data. In this context - study of the solar system and big data - the Legacy Survey of Space and Time. (LSST) should be cited. LSST will observe the visible sky from Cerro Pachón three times every ten days, registering objects as faint as r=23,5 in single-epoch images (ie, non-coadded). In particular, millions of asteroids and tens of thousands of TNOs and Centaurs will be observed. Transient events, moving objects among them, will be disseminated by LSST through alarms, about ten million a night. Thus, given the rich and voluminous mass of data, its use is of interest and requires preparation. Taking this into account, this work used the images taken during the first three years of DES to construct a portal for the prediction of stellar occultations by small solar system bodies. In addition, an analysis of the photometric potential of single-epoch images was done. This portal contemplates finding images with solar system objects among the millions of CCDs registered by DES (given the observation date, pointing coordinates and field of view), selection of these images (those with TNOs and Centaurs in the present case), astrometry, orbit refinement and prediction of stellar occultations from the refined orbit. The second release of data from the Gaia space mission - Gaia DR2 - promoted a leap in prediction quality. The analysis of light curves from observation of the occultations, as well as tasks related to the organization of international observation campaigns of these events, are part of this portal and will be implemented. This portal is an unprecedented tool in the study of small bodies from stellar occultations and will give unprecedented impetus to the works done by our research group. The photometric potential analysis describes the contribution that can be obtained from the multifilter photometry from the DES to the transnetunian region. In particular, rotational curves, taxonomic classification, absolute magnitudes, phase curves and their inclinations were addressed for a selected group of objects. In addition to the preparation of tools for photometric exploration of small bodies, the results attest to the contribution that data from 6 years of DES observations should offer to the study of these bodies. It is worth remembering that, in addition to a few hundred TNOs, DES observed more than 100.000 asteroids in its first three years of operation. With regard to TNOs, this work added photometric information to those existing in the literature, such as absolute magnitudes in different filters and taxonomy.