Banca de DEFESA: JOSIEL MENDONÇA SOARES DE SOUZA

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : JOSIEL MENDONÇA SOARES DE SOUZA
DATE: 12/07/2023
TIME: 14:00
LOCAL: online
TITLE:

Late-Time Cosmology With Third Generation Gravitational Wave Observatories

KEY WORDS:

Standard Sirens, Luminosity Distance, Cosmography, GWDALI, Einstein Telescope, Cosmic Explorer.

PAGES: 161
BIG AREA: Ciências Exatas e da Terra
AREA: Física
SUMMARY:

With the first detection of gravitational waves in 2015 by the observatories LIGO Hanford and
Livingston, a new window opened to the study of astronomy, astrophysics, and cosmology. With
gravitational waves emitted by binary systems of compact objects, such as binaries of black holes
and neutron stars, we can measure directly their luminosity distances dL , similar to type Ia super-
novae called standard candles. Thus, these gravitational wave sources received the name standard
sirens, in analogy with the standard candles. If an electromagnetic counterpart of these sources
is available, as the signal GW170817, we can identify directly their sky position, and so, their host
galaxies and redshifts z. Thus, having a relationship dL − z through detections of gravitational
waves with electromagnetic counterparts, we can perform cosmological tests, such as measur-
ing H0 , performing Bayesian model selection, and constraining cosmographic parameters, among
others. In this work, we explore the strength of the planned ground-based third generation obser-
vatories, Einstein Telescope and Cosmic Explorer to probe the evolution of the Universe’s expan-
sion. We start presenting our software GWDALI developed to estimate uncertainties in gravita-
tional wave parameters via Fisher-Matrix and beyond Gaussianity approach of likelihoods. We
also explore how much the synergy between third generation observatories can improve mea-
surements of luminosity distances of bright standard sirens (standard sirens with electromagnetic
counterparts) to get the best cosmological constants from dL − z relationships. Finally, we deal
with the cosmography approach, forecasting the maximum accuracy in the measurements of the
first three cosmographic parameters, Hubble constant H0, deceleration parameter q0 , and jerk j0
with Einstein Telescope.

COMMITTEE MEMBERS:
Externo à Instituição - ODYLIO DENYS DE AGUIAR - INPE
Externo à Instituição - RAFAEL DA COSTA NUNES
Interno - 1672854 - RAIMUNDO SILVA JUNIOR
Presidente - ***.141.018-** - RICCARDO STURANI - UFRN
Interno - 1390849 - RODRIGO FERNANDES LIRA DE HOLANDA