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相关论文: On Effective Degrees of Freedom in the Early Unive…

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The effective number of neutrinos, $N_{\text{eff}}$, obtained from CMB fluctuations accounts for all effectively massless degrees of freedom present in the Universe, including but not limited to the three known neutrinos. Using a…

核理论 · 物理学 2018-05-09 Jeremiah Birrell , Johann Rafelski

We study the thermophysical properties of dense helium plasmas by using quantum molecular dynamics and orbital-free molecular dynamics simulations, where densities are considered from 400 to 800 g/cm$^{3}$ and temperatures up to 800 eV.…

材料科学 · 物理学 2011-06-27 Cong Wang , Xian-Tu He , Ping Zhang

The connection between cosmological observations and neutrino physics is discussed in detail. Neutrinos decouple from thermal contact in the early Universe at a temperature of order 1 MeV which coincides with the temperature where light…

高能物理 - 唯象学 · 物理学 2008-11-26 Steen Hannestad

We study the quark-hadron phase transition within an effective model of QCD, and find that in a reasonable range of the main parameters of the model, bodies with quark content between $10^{-2}$ and 10 solar masses can have been formed in…

高能物理 - 唯象学 · 物理学 2008-11-26 N. Borghini , W. N. Cottingham , R. Vinh Mau

We study the dynamics of first-order phase transition in the early Universe when it was $10-50 \mu s$ old with quarks and gluons condensing into hadrons. We look at how the Universe evolved through the phase transition in small as well as…

高能物理 - 唯象学 · 物理学 2009-10-31 Deepak Chandra , Ashok Goyal

Quark-gluon plasmas formed in heavy ion collisions at high energies are well described by ideal classical fluid equations with nearly zero viscosity. It is believed that a similar fluid permeated the entire universe at about three…

量子物理 · 物理学 2017-02-28 Mark Davidson

Imposing an equilibrium between the thermal pressure of deconfined quarks and gluons and the dynamical compression pressure exercised by in-flowing nuclear matter, we study the initial thermal conditions reached in a quark-gluon plasma…

高能物理 - 唯象学 · 物理学 2009-10-30 Jean Letessier , Jan Rafelski , Ahmed Tounsi

An extended chiral SU(3) model is applied to the description of dense, hot and strange hadronic matter. The degrees of freedom are the baryon octet and decuplet and the spin-0 and spin-1 meson multiplets. The parameters of the model are…

Visible matter in the current Universe is a consequence of the phase transition of the strong force, quantum chromodynamics (QCD). This phase transition has occurred at the Universe temperature around $T_c\simeq 165\,$MeV while it was…

高能物理 - 唯象学 · 物理学 2018-07-19 Jihn E. Kim , Se-Jin Kim

Results on initial transverse energy production based on NLO perturbative QCD calculation with final state saturation of produced minijets are used to fix the initial energy density of produced matter. Assuming rapid thermalization, this…

核理论 · 物理学 2009-11-07 P. V. Ruuskanen

Existence and properties of the electroweak phase transition in the early universe depend strongly on the mass of the Higgs scalar M_H. There is presumably no true symmetry restoration at high temperature. Nevertheless, a first order phase…

高能物理 - 唯象学 · 物理学 2008-02-03 Bastian Bergerhoff , Christof Wetterich

High-energy heavy-ion collisions provide a unique opportunity to study the properties of the hot and dense strongly-interacting system composed of deconfined quarks and gluons -- the quark-gluon plasma (QGP) -- in laboratory conditions. The…

高能物理 - 实验 · 物理学 2018-08-07 Mateusz Ploskon

The early universe is dominated by phenomena at high temperatures. The thermal effects decrease during evolution of the universe. However there are some phenomena, such as processes inside stars and black holes, where the role of the…

广义相对论与量子宇宙学 · 物理学 2017-11-27 A. F. Santos , S. C. Ulhoa , Faqir C. Khanna

We consider thermodynamics of the excluded volume particles at finite temperature and chemical potential, in the low density approximation. We assume Boltzmann statistics and study the influence of the excluded volume on an ideal gas…

高能物理 - 唯象学 · 物理学 2016-02-17 Krzysztof Redlich , Kacper Zalewski

This is an introduction to the study of strongly interacting matter. We survey its different possible states and discuss the transition from hadronic matter to a plasma of deconfined quarks and gluons. Following this, we summarize the…

高能物理 - 唯象学 · 物理学 2015-05-13 Helmut Satz

We investigate an effective relativistic equation of state at finite values of temperature and baryon chemical potential with the inclusion of the full octet of baryons, the Delta-isobars and the lightest pseudoscalar and vector meson…

核理论 · 物理学 2013-11-14 A. Lavagno

From a combination of probes including the cosmic microwave background (WMAP7+SPT), Hubble constant (HST), baryon acoustic oscillations (SDSS+2dFGRS), and supernova distances (Union2), we have explored the extent to which the constraints on…

宇宙学与河外天体物理 · 物理学 2013-04-30 Shahab Joudaki

We study the effects of the equation of state on the nuclear suppression of heavy flavours in quark gluon plasma and estimate the initial entropy density of the system produced at the highest RHIC energy. For this purpose we have used the…

核理论 · 物理学 2012-04-19 Surasree Mazumder , Jan-e Alam

Various thermodynamic quantities for baryon-free matter are calculated by combining the most reliable non-perturbative and perturbative calculations, especially the most recent ones including as many quark flavors as possible. We extend…

高能物理 - 唯象学 · 物理学 2019-11-05 Abdel Nasser Tawfik , Igor Mishustin

Instanton effects may have implications for hadronization of quark-gluon plasma as it cools. Here we study dispersion relations of mesons in a strongly coupled plasma with an instanton background present. It will be shown that at higher…

高能物理 - 理论 · 物理学 2016-04-19 Majid Dehghani , Behrouz Mirza