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Related papers: New class of compact stars: Pion stars

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Pion stars consisting of Bose-Einstein condensed charged pions have recently been proposed as a new class of compact stars. We use the two-particle irreducible effective action to leading order in the $1/N$-expansion to describe charged and…

High Energy Physics - Phenomenology · Physics 2018-07-25 Jens O. Andersen , Patrick Kneschke

We study self-gravitating multi-pion systems (pion stars) in a state of the Bose condensate. To ensure stability of such stars, it is assumed that they are immersed in the lepton background. Two different phenomenological equations of state…

High Energy Physics - Phenomenology · Physics 2023-06-28 O. S. Stashko , O. V. Savchuk , L. M. Satarov , I. N. Mishustin , M. I. Gorenstein , V. I. Zhdanov

The behavior of pions is studied in systems where their normal leptonic decay is forbidden. When thermal fluctuations are present, a low decay rate is generated, and as a consequence of lepton recombination, the amount of pions remains…

High Energy Physics - Phenomenology · Physics 2019-04-10 Cristian Villavicencio , Marcelo Loewe , Alfredo Raya

We consider compact boson stars that arise for a V-shaped scalar field potential. They represent a one parameter family of solutions of the scaled Einstein-signum-Gordon equations. We analyze the physical properties of these solutions and…

General Relativity and Quantum Cosmology · Physics 2015-06-05 Betti Hartmann , Burkhard Kleihaus , Jutta Kunz , Isabell Schaffer

We argue that using an equilibrated gas of neutrinos it is possible to probe the phase diagram of QCD for finite isospin and small baryon chemical potentials. We discuss this region of the phase diagram in detail and demonstrate that for…

High Energy Physics - Phenomenology · Physics 2010-04-14 Hiroaki Abuki , Tomas Brauner , Harmen J. Warringa

We consider charged boson stars and study their effect on the structure of the vacuum. For very compact particle like ``stars", with constituent mass $m_{*}$ close to the Planck mass $m_{Pl}$, i.e. $m_{*}^{2} = {\cal O} (\alpha…

Astrophysics · Physics 2019-08-17 P. Jetzer , P. Liljenberg , B. -S. Skagerstam

We review particle-like configurations of complex scalar field, localized by gravity, so-called boson stars. In the simplest case, these solutions posses spherical symmetry, they may arise in the massive Einstein-Klein-Gordon theory with…

General Relativity and Quantum Cosmology · Physics 2022-04-14 Yakov Shnir

It has been shown that scalar fields can form gravitationally bound compact objects called boson stars. In this study, we analyze boson star configurations where the scalar fields contain a small amount of angular momentum and find two new…

High Energy Physics - Theory · Physics 2021-04-28 Felix Kling , Arvind Rajaraman , Freida Liz Rivera

We investigate antikaon condensation in compact star matter using a relativistic mean field model. Antikaon condensates make the equation of state softer resulting in a smaller maximum mass star compared to the case without condensate. It…

Astrophysics · Physics 2008-11-26 Sarmistha Banik , Debades Bandyopadhyay

We investigate the possible formation of a Bose-Einstein condensed phase of pions in the early Universe at nonvanishing values of lepton flavor asymmetries. A hadron resonance gas model with pion interactions, based on first-principle…

High Energy Physics - Phenomenology · Physics 2021-01-08 Volodymyr Vovchenko , Bastian B. Brandt , Francesca Cuteri , Gergely Endrődi , Fazlollah Hajkarim , Jürgen Schaffner-Bielich

We develop a theoretical framework to study slowly rotating compact stars in a rather general class of alternative theories of gravity, with the ultimate goal of investigating constraints on alternative theories from electromagnetic and…

General Relativity and Quantum Cosmology · Physics 2015-05-30 Paolo Pani , Emanuele Berti , Vitor Cardoso , Jocelyn Read

In this paper, we consider the mimetic gravitational theory to derive a novel category of anisotropic star models. To end and to put the resulting differential equations into a closed system, the form of the metric potential $g_{rr}$ as…

General Relativity and Quantum Cosmology · Physics 2021-10-11 G. G. L. Nashed

We study novel solitonic solutions to Einstein-Klein-Gordon theory in the presence of a periodic scalar potential arising in models of axion-like particles. The potential depends on two parameters: the mass of the scalar field $m_a$ and the…

General Relativity and Quantum Cosmology · Physics 2020-05-27 Davide Guerra , Caio F. B. Macedo , Paolo Pani

In this work we present some new results obtained in a study of the phase diagram of charged compact boson stars in a theory involving a complex scalar field with a conical potential coupled to a U(1) gauge field and gravity. We here obtain…

High Energy Physics - Theory · Physics 2017-09-28 Sanjeev Kumar , Usha Kulshreshtha , Daya Shankar Kulshreshtha , Sarah Kahlen , Jutta Kunz

The gross structure of compact stars composed of pion superfluid quark matter is investigated in the frame of Nambu-Jona-Lasinio model. Under the Pauli-Villars regularization scheme, the uncertainty of the thermodynamic functions for…

Nuclear Theory · Physics 2015-06-18 Shijun Mao

We investigate the structure and stability properties of compact astrophysical objects that may be formed from the Bose-Einstein condensation of dark matter. Once the critical temperature of a boson gas is less than the critical…

Cosmology and Nongalactic Astrophysics · Physics 2013-03-25 X. Y. Li , T. Harko , K. S. Cheng

We investigate the properties of high density compact objects in a vector type theory, inspired by Einstein's 1919 theory of elementary particles, in which Einstein assumed that elementary particles are held together by gravitational as…

General Relativity and Quantum Cosmology · Physics 2022-04-12 Zahra Haghani , Tiberiu Harko

Aims: In the present work we search for a new model of compact star within embedding class one spacetime i.e., four dimensional spacetime embedded in five dimensional Pseudo Euclidean space. Methods: In particular we propose a new mass…

General Physics · Physics 2017-10-11 S. K. Maurya , Y. K. Gupta , Farook Rahaman , Monsur Rahaman , Ayan Banerjee

We show the possible existence of compact stars having a surface composed of a mixed phase of quarks and hadrons. This scenario can be realized both for self-bound stars, satisfying the so-called Witten-Bodmer hypothesis, and for…

High Energy Physics - Phenomenology · Physics 2009-11-07 Alessandro Drago , Andrea Lavagno

We study pion and kaon condensation using three-flavor chiral perturbation theory at finite isospin and strangeness quark chemical potentials {\mu}I and {\mu}S . The phase diagram consists of a vacuum phase and three distinct Bose condensed…

High Energy Physics - Phenomenology · Physics 2022-06-10 Jens O. Andersen , Martin Kjøllesdal Johnsrud
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