Advanced search
Start date
Betweenand

Compact stars in binaries: investigating the composition of superdense matter

Grant number: 11/23996-9
Support type:Scholarships in Brazil - Post-Doctorate
Effective date (Start): May 01, 2012
Effective date (End): July 31, 2017
Field of knowledge:Physical Sciences and Mathematics - Astronomy
Principal Investigator:Jorge Ernesto Horvath
Grantee:Marcio Guilherme Bronzato de Avellar
Home Institution: Instituto de Astronomia, Geofísica e Ciências Atmosféricas (IAG). Universidade de São Paulo (USP). São Paulo , SP, Brazil
Associated research grant:13/26258-4 - Superdense matter in the universe, AP.TEM
Associated scholarship(s):15/20553-0 - Modelling the quasi-periodic oscillations and their respective time lags in neutron star low-mass X-ray binaries - the NS-LMXB 4U 1636-53 as a case study, BE.EP.PD

Abstract

Neutron stars are extreme objects in the universe. Their birth is marked by the death of a star with mass between 8 and 25 solar masses in a cataclysmic explosive event, releasing 10^53 erg of energy and can suppress the brightness of an entire galaxy. After the contraction of the iron core of the progenitor, the remnant is a neutron star with 1.4 solar masses and 10 km of radius, which means an average density 10^14 g/cm^3.Extreme objects allow us to study extreme physics and extreme physics means involving various branches of science and connect them in new and differential ways, leading to advances in our understanding of the phenomenon. More specifically, neutron stars are natural laboratories to test two of the most fundamental theories for the construction of reality: the theory of general relativity of gravitation in the strong field regime and the physics of matter at extremely high densities and temperatures. Both tests are impossible to be performed in laboratories on Earth with today's technology.But it is not only the theoretical point of view that the study of neutron stars leads to advances in the understanding of Nature. It also leads to technological advances, especially in the field of observational astrophysics. We have always to improve our detectors and telescopes in order to understand more clearly the astrophysical signatures of these compact objects in all its varieties, which would also lead us to a greater understanding of nature.The group of Professor Jorge Horvath, my supervisor at the doctorate, has been working on this topic for a long time, but always more focused on theory. Now, my contribution to the group is to connect the theory to observations. During my PhD I've been searching for the observational link to theory, having spent one year at Kapteyn Astronomical Institute in Groningen, The Netherlands, working with Professor Mariano Mendez on x-ray emitting systems containing a neutron star. There, I acquired the necessary experience to conduct this observational project, collaborating in a way that complements the group's goals.Because the rapid technological developments of the last decade, a vast amount of data was obtained, but much remains to be analyzed. We now have in hand, already available for treatment, data from five very special systems that will drive us to a real breakthrough in the restriction of masses and radii of neutron stars, allowing us to select a smaller set of possible equations of state for the description superdense matter inside the neutron stars, as best described throughout this manuscript.

Articles published in Agência FAPESP about the scholarship:
Brazilians create model to evaluate possibility of life on Jupiter’s icy moon  

Scientific publications (4)
(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)
MENDES, CAMILE; DE AVELLAR, MARCIO G. B.; HORVATH, J. E.; DE SOUZA, RODRIGO A.; BENVENUTO, O. G.; DE VITO, M. A. Magnetic field decay in black widow pulsars. Monthly Notices of the Royal Astronomical Society, v. 475, n. 2, p. 2178-2184, APR 2018. Web of Science Citations: 0.
ALTAIR, THIAGO; DE AVELLAR, MARCIO G. B.; RODRIGUES, FABIO; GALANTE, DOUGLAS. Microbial habitability of Europa sustained by radioactive sources. SCIENTIFIC REPORTS, v. 8, JAN 10 2018. Web of Science Citations: 1.
DE AVELLAR, MARCIO G. B.; MENDEZ, MARIANO; ALTAMIRANO, DIEGO; SANNA, ANDREA; ZHANG, GUOBAO. Phase lags of quasi-periodic oscillations across source states in the low-mass X-ray binary 4U 1636-53. Monthly Notices of the Royal Astronomical Society, v. 461, n. 1, p. 79-92, SEP 1 2016. Web of Science Citations: 6.
DE AVELLAR, M. G. B.; DE SOUZA, R. A.; HORVATH, J. E.; PARET, D. M. Information theoretical methods as discerning quantifiers of the equations of state of neutron stars. Physics Letters A, v. 378, n. 47, p. 3481-3487, NOV 7 2014. Web of Science Citations: 5.

Please report errors in scientific publications list by writing to: cdi@fapesp.br.
Distribution map of accesses to this page
Click here to view the access summary to this page.