68 citations · 176 across the 13 of their papers we have counts for
15 papers
The Galactic Black Hole mass distribution
L S. Rocha, N. Pires, L. M. de Sá +8
The population of extragalactic black holes has been significantly expanded and better understood since the first detection of gravitational waves. Over the past decade, approximat…
The mass of the neutron star in 4U 1820-30 revisited
Marcio G B de Avellar, Jorge E Horvath, Nathalia D Pires +7
We revisit the mass of the neutron star in the ultracompact binary 4U 1820--30 in light of a recently reported transient absorption feature at about 3.8 keV, interpreted as a gravi…
Evolution of long-period compact radio sources driven by winds
J. E. Horvath, Lucas M. de Sá, Lívia S. Rocha +3
We address in this work the nature and evolution of the long-period compact star sources, which has recently added several unexpected members. The central hypothesis is that partic…
Mass Distribution and Maximum Mass of Neutron Stars: Effects of Orbital Inclination Angle
Lívia S. Rocha, Jorge E. Horvath, Lucas M. de Sá +3
Matter at ultra-high densities finds a physical realization inside neutron stars. One key property is their maximum mass, which has far-reaching implications for astrophysics and t…
A visão da BBChain sobre o contexto tecnológico subjacente à adoção do Real Digital
Marcio G B de Avellar, Alexandre A S Junior, André H G Lopes +3
We explore confidential computing in the context of CBDCs using Microsoft's CCF framework as an example. By developing an experiment and comparing different approaches and performa…
A light strange star in the remnant HESS J1731-347: minimal consistency checks
J. E. Horvath, L. S. Rocha, L. M. de Sá +5
Context: Recently, Doroshenko and collaborators reported a very low-mass compact star, a Central Compact Object named XMMU J173203.3-344518 inside the supernova remnant HESS J1731-…
Sudden discharge of young charged magnetars as a new model for FRBs
Marcio G. B. de Avellar, Pedro P. B. Beaklini, Sílvia P. Nunes +2
We propose a new model for Fast Radio Bursts (FRBs) based on a sudden discharge of a charged young magnetar, caused by the short falling timescale of oppositely charged particles o…
Fast Radio Bursts as crustal dynamical events induced by magnetic field evolution in young magnetars
J. E. Horvath, P. H. R. S. Moraes, M. G. B. de Avellar +1
We revisit in this work a model for repeating Fast Radio Bursts based of the release of energy provoked by the magnetic field dynamics affecting a magnetar's crust. We address the…
Phase lags of quasi-periodic oscillations across source states in the low-mass X-ray binary 4U 1636-53
Marcio G B de Avellar, Mariano Méndez, Diego Altamirano +2
While there are many dynamical mechanisms and models that try to explain the origin and phenomenology of the quasi-periodic oscillations (QPOs) seen in the X-ray light curves of lo…
Trends of Stellar Entropy along Stellar Evolution
Marcio G. B. de Avellar, Rodrigo A. de Souza, Jorge E. Horvath
This paper is devoted to discuss the difference in the thermodynamic entropy budget {\it per baryon} in each type of stellar object found in Universe. We track and discuss the actu…
Statistical measure of complexity in compact stars with global charge neutrality
Rodrigo Alvares de Souza, Marcio Guilherme Bronzato de Avellar, Jorge Ernesto Horvath
Recently, it has been suggested that a critical electrical field arises during the gravitational collapse of massive stars leading to a vacuum polarization. This, in turn, leads to…
Entropy, Disequilibrium and Complexity in Compact Stars: An information theory approach to understand their Composition
Marcio G B de Avellar, Jorge E Horvath
The composition of neutron stars is an issue that has been studied for decades. Yet we do not know exactly what these very compact objects are made of. At this stage of the technol…
Time lags of the kilohertz quasi-periodic oscillations in the low-mass X-ray binaries 4U 1608--52 and 4U 1636--53
M. G. B. de Avellar, M. Méndez, A. Sanna +1
(abridged) We studied the energy and frequency dependence of the Fourier time lags and intrinsic coherence of the kHz QPOs in the NS LMXBs 4U 1608-52 and 4U 1636-53 using RXTE data…
Self-bound models of compact stars and recent mass-radius measurements
M. G. B. de Avellar, J. E. Horvath, L. Paulucci
The exact composition of a specific class of compact stars, historically referred to as "neutron stars", is still quite unknown. Possibilities ranging from hadronic to quark degree…
Exact and Quasi-exact Models of Strange Stars
M. G. B. Avellar, J. E. Horvath
We construct and compare a variety of simple models for strange stars, namely, hypothetical self-bound objects made of a cold stable version of the quark-gluon plasma. Exact, quasi…