ترغب بنشر مسار تعليمي؟ اضغط هنا

Charged charm stars

63   0   0.0 ( 0 )
 نشر من قبل Victor Goncalves
 تاريخ النشر 2020
  مجال البحث فيزياء
والبحث باللغة English




اسأل ChatGPT حول البحث

The study of the general properties and stability of charm stars with a net electric charge is performed within the MIT bag model framework. We consider two different models for the electric charge distribution and demostrate that both imply stellar configurations with larger masses and that satisfy the equilibrium condition. The dynamical stability against radial oscillations is investigated. Our results demonstrate that the eigenfrequencies are modified by the presence of a net electric charge, but the instability, previously demonstrated for the electrically neutral case, is also present in charged charm stars.



قيم البحث

اقرأ أيضاً

We assume that ultra dense neutron stars are endowed with a distribution of electric charge and study the twin star solutions and their properties resulting from a first order transition from confined hadronic to deconfined quark phases. Two distinct phenomenological treatments for the phase transition are considered and the values for the maximum gravitational masses of the hadronic and hybrid configurations are estimated for different values of the total electric charge. We demonstrate that stable compact charged twin stars exist, with charged stars being more massive than their neutral counterparts, and that the standard ${2.2}{M_{odot}}$ constraint is surpassed for large values of the electric charge. In particular, our results suggest that the unknown compact object of $approx {2.6}{M_{odot}}$ measured in the GW190814 event might be a charged star.
We study the effects of heavy quarks on the equation of state for cold and dense quark matter obtained from perturbative QCD, yielding observables parametrized only by the renormalization scale. We investigate the thermodynamics of charm quark matter under the constraints of $beta$ equilibrium and electric charge neutrality in a region of densities where perturbative QCD is, in principle, much more reliable. We also analyze the stability of charm stars, which might be realized as a new branch of ultradense hybrid compact stars, and find that such quark stars are unstable under radial oscillations.
We demonstrate that the observation of neutron stars with masses greater than one solar mass places severe demands on any exotic neutron decay mode that could explain the discrepancy between beam and bottle measurements of the neutron lifetime. If th e neutron can decay to a stable, feebly-interacting dark fermion, the maximum possible mass of a neutron star is 0.7 solar masses, while all well-measured neutron star masses exceed one solar mass. The survival of $2 M_odot$ neutron stars therefore indicates that any explanation beyond the Standard Model for the neutron lifetime puzzle requires dark matter to be part of a multi-particle dark sector with highly constrained interactions.
The discovery of non-diffuse sources of gravitational waves through compact-object mergers opens new prospects for the study of physics beyond the Standard Model. In this Letter, we consider the implications of the observation of GW190814, involving a coalescence of a black hole with a $sim$2.6 $M_odot$ compact object, which may be too massive to be a neutron star, given our current knowledge of the nuclear matter equation of state. We consider the possibility of a new force between quarks, suggested in other contexts, that modifies the neutron star equation of state, particularly at supranuclear densities. We evaluate how this modification can impact a neutron stars mass and radius to make the observed heavy compact object more probably a neutron star, rather than a black hole, and suggest that further such objects may yet be found. We note the terrestrial and astrophysical measurements that could confirm our picture.
We study the probability for nucleation of quark matter droplets in the dense cold cores of old neutron stars induced by the presence of a self-annihilating dark matter component, $chi$. Using a parameterized form of the equation of state for hadroni c and quark phases of ordinary matter, we explore the thermodynamic conditions under which droplet formation is facilitated by the energy injection from $chi$ self-annihilations. We obtain the droplet nucleation time as a function of the dark matter candidate mass, $m_chi$. We discuss further observational consequences.
التعليقات
جاري جلب التعليقات جاري جلب التعليقات
سجل دخول لتتمكن من متابعة معايير البحث التي قمت باختيارها
mircosoft-partner

هل ترغب بارسال اشعارات عن اخر التحديثات في شمرا-اكاديميا