Constança Providencia
(University of Coimbra)
15/06/2015, 14:00
It will be discussed how the crust-core matching influences the NS radius and the crust thickness within relativistic mean-field nuclear models. A set of models that predict 2$M_\odot$ stars will be considered. It will be proposed an adequate crust-core matching. The inner crust will described in the Thomas-Fermi approximation within the single heavy cluster approach. The effect of...
Dr
Michał Bejger
(N. Copernicus Astronomical Center, PAS)
15/06/2015, 14:25
Using a recent equation of state (Benic et al., 2015, A&A 577, A40) I will discuss
the stability of rotating neutron stars with strong phase
transitions (so-called twin family of neutron stars). The existence of an instability
region separating the twin families - a direct outcome of the strong phase transition
- creates several astrophysical implications that are interesting from the...
Prof.
Debades Bandyopadhyay
(Saha Institute of Nuclear Physics)
15/06/2015, 14:50
Supernova explosions are spectacular astronomical events. At the same time,
the understanding of the final journey of a massive star after its fuel has
been exhausted is a challenging problem. The outcome of it is a core collapse
supernova and the residue may take the form of either a neutron star
or a black hole. The core collapse supernova explosion mechanism is being investigated
over...
Dr
Helena Pais
(University of Coimbra)
15/06/2015, 15:15
The pasta phase in core-collapse supernova matter (finite temperatures and fixed proton fractions) is studied within relativistic mean field models. Three different calculations
are used for comparison, the Thomas-Fermi (TF), the Coexisting Phases (CP) and the Compressible Liquid Drop (CLD) approximations. The effects of including light clusters in
nuclear matter and the densities at which...
Ms
Hai Tan Ngo
(Vinatom,Vietnam/IPNLyon, France)
15/06/2015, 15:40
A consistent Hartree-Fock study of the hot, beta-stable baryonic matter of proto-neutron star (PNS) is done based on several choices of the effective (density dependent) nucleon-nucleon interaction, which have been successfully used in different nuclear structure and reaction studies. The equations of state associated with different behaviors of the symmetry energy at supranuclear densities...
Dr
Peter Kovacs
(Wigner RCP)
15/06/2015, 16:35
Chiral phase transition is investigated in an $SU(3)_L \times SU(3)_R$
symmetric vector meson extended linear sigma model with additional
constituent quarks and Polyakov loops (extended Polyakov quark meson
model). The parameterization of the Lagrangian is done at zero
temperature in a hybrid approach, where the mesons are treated at
tree-level, while the constituent quarks at 1-loop...
Dr
Matthias Hempel
(Basel University)
15/06/2015, 17:00
Cluster formation is a fundamental aspect of the equation of state (EOS) of
warm and dense nuclear matter such as can be found in supernovae (SNe). Similar
matter can be studied in heavy-ion collisions (HIC). We use the experimental
data of Qin et al. [Phys. Rev. Lett. 108, 172701 (2012)] to test calculations
of cluster formation and the role of in-medium modifications of...
Dr
Takami Kuroda
(University of Basel)
15/06/2015, 17:25
In this talk, we present our recently performed 3D fully relativistic long term simulations (Tpb~300-400ms) of gravitational collapse of massive progenitor stars with adopting several modern EoSs of Hempel et al.'12 and of Steiner et al.'13. Through these multiple EoSs and progenitor models, we found more massive progenitor star and softer equation of state lead to more vigorous SASI activity...
Prof.
Dubravko KLABUCAR
(Physics Department, PMF, Zagreb University)
15/06/2015, 17:50
The analytic structure of certain Ansaetze for quark propagators
in the nonperturbative regime of QCD is investigated. When choosing
physically motivated parameterization of the momentum-dependent
dressed quark mass function M(p^2), with definite analytic structure,
it is highly nontrivial to predict and control the analytic structure
of the corresponding nonperturbative quark...
Mr
Peter Pósfay
(Eötvös Lóránd University)
16/06/2015, 14:00
Functional renormalization group (FRG) is an exact method for taking
into account the effect of quantum fluctuations in the effective action of the
system. The FRG method applied to effective theories of nuclear matter yields
equation of state witch incorporates quantum fluctuations of the fields.
Using the local potential approximation the equation of state for Walecka-type
models of...
Dr
Kristian Petrik
(Institute of Physics, Slovak Academy of Sciences)
16/06/2015, 14:25
Modern and accurate observations of compact stars are invaluable sources of very important information about dense nuclear matter. One of the biggest breakthroughs in this field is definitely an experimental confirmation of the existence of very massive pulsars that brought new and very powerful constraints on all model descriptions. Our aim is to develop a relativistic energy density...
Dr
Evgeni Kolomeitsev
(Matej Bel University)
16/06/2015, 14:50
The equation of state of cold baryonic matter is studied within a relativistic mean-field model with hadron masses and coupling constants depending on the scalar field. All hadron masses undergo a universal scaling, whereas the coupling constants can scale differently.
The proper choice of the scaling function allows to control stiffness of the equation of state in different energy range. The...
Dr
Anthea Francesca Fantina
(Institut d'Astronomie et d'Astrophysique, Université Libre de Bruxelles)
16/06/2015, 15:15
In this talk, a set of unified equations of state (EoSs) of neutron-star matter calculated within the nuclear energy-density functional theory, and based on generalised Skyrme energy-density functionals developed by the Brussels-Montreal collaboration, will be presented. The structure of neutron stars constructed with these EoSs will be discussed in connection with both recent astrophysical...
Dr
David Alvarez-Castillo
(Joint Institute for Nuclear Research)
16/06/2015, 15:40
In order to prove the existence of a critical end point (CEP) in the
QCD phase diagram it is sufficient to demonstrate that at zero
temperature $T=0$ a first order phase transition exists as a function
of the baryochemical potential $\mu$, since it is established
knowledge from ab-initio lattice QCD simulations that at $\mu=0$ the
transition on the temperature axis is a crossover.
We...
Dr
Aleksi Vuorinen
(University of Helsinki)
16/06/2015, 16:35
I will describe what is currently known about the behavior of the Equation of State (EoS) of cold and dense quark matter based on first principles calculations utilizing perturbation theory in the deconfined phase of QCD. In addition, I will argue that by combining this information with known results on the EoS of low-density nuclear matter, it is possible to very efficiently constrain the...
Dr
Isaac Vidana
(University of Coimbra)
16/06/2015, 17:00
We construct two-meson exchange three-baryon potentials between two
nucleons and one hyperon (NNY). Our NNY potentials are built in order
to be consistent with the most recent version of the two-body
nucleon- hyperon (NY) potential of the Juelich group. In particular,
we focus on the NNΛ and NNΣ forces since the Λ and Σ− are the first
hyperons expected to appear in microscopic...
144.
Properties of neutron-star crusts with accurately calibrated nuclear energy density functionals
Dr
Nicolas Chamel
(Université Libre de Bruxelles)
16/06/2015, 17:25
Observations from ground- and space-based instruments have lead to the discovery of remarkable astrophysical phenomena that are thought to be intimately related to the physics of neutron-star crusts like pulsar sudden spin-ups (so called “glitches”), quasi-periodic oscillations in the giant flares from soft gamma-ray repeaters, X-ray bursts and superbursts, or the cooling of quasi-persistent...
Mr
Erbil GÜGERCINOGLU
(Istanbul University Astronomy and Space Sciences Department)
16/06/2015, 17:50
As theoretical calculations and recent simulations indicate, neutron stars must have a stronger toroidal field component in the outer core which surrounds the poloidal field. Then, this toroidal field in the form of flux lines will offer pinning sites for vortex lines similar to the conditions in the inner crust. As we have shown, the moment of inertia of the corresponding region can be larger...
Mr
Francesco Coti Zelati
(Anton Pannekoek Institute for Astronomy, University of Amsterdam)
18/06/2015, 14:00
In 2013 April a new magnetar, SGR 1745−2900, was discovered as it entered an outburst at
only 2.4 arcsec angular distance from Sagittarius A∗, the supermassive black hole at the centre of the Milky Way. The new source was detected both in the radio and X-ray bands, with a peak X-ray luminosity L_X ∼ 5 × 10^{35} erg s^{−1}. I will present the results of the long-term Chandra (25 observations)...
Dr
Brynmor Haskell
(University of Melbourne)
18/06/2015, 14:25
Pulsar glitches, i.e. sudden jumps in the frequency of spinning down pulsars, are thought to be the direct manifestation of a superfluid component in the pulsar interior. The exact mechanisms that gives rise to these phenomena has, however, remained a mystery for over 40 years.
The wealth of data that is now available suggests that glitches may be the consequence of the superfluid being in a...
Dr
Lorenzo Ducci
(University of Tuebingen)
18/06/2015, 14:50
Glitches have been observed in isolated pulsars, while a clear detection in accretion-powered X-ray pulsars is still lacking. We use the "snowplow" model for pulsar glitches of Pizzochero (2011) and starquake models to determine for the first time the expected properties of glitches in accreting pulsars and their observability. We also investigate the possibility that anti-glitches occur in...
Dr
Anna Bilous
(Radboud University Nijmegen)
18/06/2015, 15:15
PSR B0943+10 is one of the best examples of the rare class of mode-switching pulsars. Unlike most of the pulsar population, PSR B0943+10 has two stable modes of radio emission, each with its own distinct radio profile morphology and sinlge-pulse behaviour. The pulsar switches between "Bright" and "Quiet" modes once every few hours and the transition takes less than a few stellar rotations. The...
Ms
Alice Borghese
(Anton Pannekoek Institute for Astronomy)
18/06/2015, 16:10
In this talk I would like to report the discovery of a narrow
phase-dependent absorption feature in the X-ray spectrum of the nearby
X-ray Dim Isolated Neutron Star RX J0720.4-3125. This feature was
discovered performing a detailed phase-resolved spectral analysis
using XMM-Newton observations which cover 12 years. The line seems to
be stable in time over this timespan and is present in...
Dr
Blagoy Rangelov
(The George Washington University)
18/06/2015, 16:35
It is extremely rare when a binary is found to be associated with supernova remnant. It is also rare when a high-mass binary is bright in gamma-rays. SNR G284.3-1.8 appears to be a unique remnant hosting such a binary. We present results from Chandra and XMM-Newton observations of the SNR and the binary. G284.3-1.8 has asymmetrically distributed Mg-rich ejecta, which has only been observed in...
Mr
Gregory Ashton
(University of Southamton)
18/06/2015, 17:00
Variability in the arrival times of pulsars, often collectively known as timing
noise, poses a significant opportunity to learn about the physics of neutron
stars. The diversity of observed timing noise is matched by the number of the
models attempting to explain the phenomenon, but no single model can claim to provide a
complete explanation. Recent results in the literature suggest that...
