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Before massive stars heavier than $(8 \cdots 10)$ solar masses evolve to the phase of a gravitational core collapse, they will emit a huge number of MeV-energy neutrinos that are mainly produced in the thermal processes and nuclear weak interactions. The detection of such pre-supernova (pre-SN) neutrinos could provide an important and independent early warning for the optical observations of core-collapse SNe. In this paper, we investigate the prospects of future large liquid-scintillator detectors for the observation of pre-SN neutrinos in both $\bar{\nu}^{}_e + p \to e^+ + n$ and $\nu (\bar{\nu}) + e^- \to \nu (\bar{\nu}) + e^-$ reaction channels, where $\nu$ ($\bar{\nu}$) denotes neutrinos (antineutrinos) of all three flavors. We propose a quantitative assessment of the capability in terms of three working criteria, namely, how far the SN distance can be covered, how long the early warning before the core collapse can be sent out, and how well the direction pointing to the SN can be determined. The dependence of the final results on the different models of progenitor stars, neutrino flavor conversions and the relevant backgrounds is also discussed., Comment: 26 pages, 8 figures and 3 tables, more discussions added, to be published in JCAP

In this paper, considering the influence of the principle of generalized uncertainty (GUP), the phase transition of a Schwarzschild black hole with global monopole is discussed. First, we use the generalized Dirac equation to obtain corrected Hawking temperature, local temperature, black hole residue, black hole entropy, thermal capacity, and other thermodynamic quantities. Then, we use images to analyze the effects of generalized uncertainty parameters on phase transitions and the effects of magnetic monopole parameters on phase transitions. Finally, we study the thermodynamic stability and phase change structure under the influence of the principle of generalized uncertainty. The results show that, in the black hole with global monopole, there are first-order and second-order phase transitions. In addition, the general uncertainty parameters and monopole parameters will affect the black hole residues., Comment: 16 pages, 7 figures

A popular Adam--Gibbs scenario has suggested that the excess entropy of glass and liquid over crystal dominates the dynamical arrest at the glass transition with exclusive contribution from configurational entropy over vibrational entropy. However, an intuitive structural rationale for the emergence of frozen dynamics in relation to entropy is still lacking. Here we study these issues by atomistically simulating the vibrational, configurational, as well as total entropy of a model glass former over their crystalline counterparts for the entire temperature range spanning from glass to liquid. Besides confirming the Adam--Gibbs entropy scenario, the concept of Shannon information entropy is introduced to characterize the diversity of atomic-level structures, which undergoes a striking variation across the glass transition, and explains the change found in the excess configurational entropy. Hence, the hidden structural mechanism underlying the entropic kink at the transition is revealed in terms of proliferation of certain atomic structures with a higher degree of centrosymmetry, which are more rigid and possess less nonaffine softening modes. In turn, the proliferation of these centrosymmetric (rigid) structures leads to the freezing-in of the dynamics beyond which further structural rearrangements become highly unfavourable, thus explaining the kink in the configurational entropy at the transition.

The emission angle distribution of projectile fragments (PFs) and the temperature of PFs emission source for fragmentation of $^{56}$Fe on polyethylene, carbon and aluminum targets at the highest energy of 496 A MeV are investigated using CR-39 plastic nuclear track detector. It is found that the averaged emission angle of PFs increases with the decrease of PF charge for the same target, and no obvious dependence of angular distribution on the mass of target nucleus is found for the same PF. The cumulated squared transverse momentum distribution of PF can be well represented by a single Rayleigh distribution, the temperature of PFs emission source is extracted from the distribution, which is about 1.0-8.0 MeV and do not depend on the mass of target for PF with charge of 9<=Z<=25., Comment: 13 pages, 12 figures

The model-independent reconstruction of the energy spectra of $\overline{\nu}^{}_e$, $\nu^{}_e$ and $\nu^{}_x$ (i.e., $\nu^{}_\mu$, $\nu^{}_\tau$ and their antiparticles) from the future observation of a galactic core-collapse supernova (SN) is of crucial importance to understand the microscopic physics of SN explosions. To this end, we propose a practically useful method to combine the multi-channel detection of SN neutrinos in a large liquid-scintillator detector (e.g., JUNO), namely, the inverse beta decay $\overline{\nu}^{}_e + p \to e^+ + n$, the elastic neutrino-proton scattering $\nu + p \to \nu + p$ and the elastic neutrino-electron scattering $\nu + e^- \to \nu + e^-$, and reconstruct the energy spectra of $\overline{\nu}^{}_e$, $\nu^{}_e$ and $\nu^{}_x$ by making the best use of the observational data in those three channels. In addition, the neutrino energy spectra from the numerical simulations of the delayed neutrino-driven SN explosions are implemented to demonstrate the robustness of our method. Taking the ordinary matter effects into account, we also show how to extract the initial neutrino energy spectra in the presence of neutrino flavor conversions., Comment: 28 pages, 8 figures

In this article, close to the Planck scale, we discuss on the remnant and residue entropy from a Rutz-Schwarzschild black hole in the frame of Finsler geometry. Employing the corrected Hamilton-Jacobi equation, the tunneling radiation of a scalar particle is presented, and the revised tunneling temperature and revised entropy are also found. Taking into account generalized uncertainty principle (GUP), we analyze the remnant stability and residue entropy based on thermodynamic phase transition. In addition, the effects of the Finsler perturbation parameter, GUP parameter and angular momentum parameter on remnant and residual entropy are also discussed., Comment: 18 pages, 5 figures, 2 tables

In this paper, we show how to carry out a relatively more realistic and complete reconstruction of supernova neutrino spectra in the future large liquid-scintillator detectors, by implementing the method of singular value decomposition with a proper regularization. For a core-collapse supernova at a distance of $10~{\rm kpc}$ in the Milky Way, its $\overline{\nu}^{}_e$ spectrum can be precisely determined from the inverse beta-decay process $\overline{\nu}^{}_e + p \to e^+ + n$, for which a $20~{\rm kiloton}$ liquid-scintillator detector with the resolution similar to the Jiangmen Underground Neutrino Observatory (JUNO) may register more than 5000 events. We have to rely predominantly on the elastic neutrino-electron scattering $\nu + e^- \to \nu + e^-$ and the elastic neutrino-proton scattering $\nu + p \to \nu + p$ for the spectra of $\nu^{}_e$ and $\nu^{}_x$, where $\nu$ denotes collectively neutrinos and antineutrinos of all three flavors and $\nu^{}_x$ for $\nu^{}_\mu$ and $\nu^{}_\tau$ as well as their antiparticles. To demonstrate the validity of our approach, we also attempt to reconstruct the neutrino spectra by using the time-integrated neutrino data from the latest numerical simulations of delayed neutrino-driven supernova explosions., Comment: 26 pages, 6 figures, more discussions, final version in PRD

In this paper, the experimental (simulated) transverse momentum spectra of negatively charged pions produced at mid-rapidity in central nucleus-nucleus collisions at the Heavy Ion Synchrotron (SIS), Relativistic Heavy Ion Collider (RHIC), and Large Hadron Collider (LHC) energies obtained by different collaborations are selected by us to investigate, where a few simulated data are taken from the results of FOPI Collaboration who uses the IQMD transport code based on Quantum Molecular Dynamics. A two-component standard distribution and the Tsallis form of standard distribution are used to fit these data in the framework of a multisource thermal model. The excitation functions of main parameters in the two distributions are analyzed. In particular, the effective temperatures extracted from the two-component standard distribution and the Tsallis form of standard distribution are obtained, and the relation between the two types of effective temperatures is studied., Comment: 22 pages, 8 figures. Advances in High Energy Physics, accepted

With motivation by holography, employing black hole entropy, two point connection function and entanglement entropy, we show that, for the higher dimensional Anti-de Sitter charged hairy black hole in the fixed charged ensemble, a Van der Waals-like phase transition can be observed. Furthermore, based on the Maxwell's equal area construction, we check numerically the equal area law for a first order phase transition in order to further characterize the Van der Waals-like phase transition., Comment: 9 pages, 6 figures, 3 tables

In curved space-time, Hamilton-Jacobi equation is a semi-classical particle's motion equation, which plays an important role in the research of black hole physics. In this paper, starting from Dirac equation describing the spin 1/2 fermion and Rarita-Schwinger equation describing the spin 3/2 fermion respectively, we derive a Hamilton-Jacobi equation of the non-stationary spherically symmetric gravitational field background. Furthermore, the quantum tunneling behavior of a charged spherically symmetric black hole is investigated by using this Hamilton-Jacobi equation. The result shows that the Hamilton-Jacobi equation is helpful for people to understand the thermodynamic properties and the radiation characteristics of a black hole., Comment: 7 pages

In this letter, we show that the dimensionless parameter in the generalized uncertainty principle (GUP) can be constrained by the gravitational wave event GW150914, which was discovered by the LIGO Scientific and Virgo Collaborations. Firstly, according to the Heisenberg uncertainty principle (HUP) and the data of gravitational wave event GW150914, we derive the standard energy-momentum dispersion relation and calculate the difference between the propagation speed of gravitons and the speed of light, i.e., $\Delta \upsilon$. Next, using two proposals regarding the GUP, we also generalize our study to the quantum gravity case and obtain the modified speed of gravitons. Finally, based on the modified speed of gravitons and $\Delta \upsilon$, the improved upper bounds on the GUP parameters are obtained. The results show that the upper limits of the GUP parameters $\beta_0$ and $\alpha_0$ are $2.3 \times 10^ {60}$ and $1.8 \times 10^{20}$., Comment: 8 pages, 2 Tables

The Planck length and Planck energy should be taken as invariant scales are in agreement with various theories of quantum gravity. In this scenario, the original general relativity can be changed to the so-called gravity's rainbow which produces significant modifications to the black holes' evolution. In this paper, using two kinds of rainbow functions, we investigate the thermodynamics and the phase transition of Schwarzschild black hole in the context of gravity's rainbow theory. Firstly, with the help of the Heisenberg uncertainty principle, we calculate the modified Hawking temperature. Then, based on this modification, we derive the local temperature, free energy and other thermodynamic quantities in an isothermal cavity. Finally, the critical behavior, the thermodynamic stability and phase transition of the rainbow Schwarzschild black hole are analyzed. It turns out that our results are different from the those of Hawking-Page phase transition. Meanwhile, it is found that there are many similarities and differences between rainbow functions I case and rainbow functions II., Comment: 16 pages, 6 figures, 2 tables comments are welcome

In this paper, the modified entropic force law is studied by using a new kind of generalized uncertainty principle which contains a minimal length, a minimal momentum and a maximal momentum. Firstly, the quantum corrections to the thermodynamics of a black hole is investigated. Then, according to Verlinde's theory, the generalized uncertainty principle (GUP) corrected entropic force is obtained. The result shows that the GUP corrected entropic force is related not only to the properties of the black holes, but also to the Planck length and the dimensionless constants $\alpha _{\rm{0}}$ and $\beta _{\rm{0}}$. Moreover, based on the GUP corrected entropic force, we also derive the modified Einstein's field equation (EFE) and the modified Friedmann equation., Comment: 16 pages. arXiv admin note: substantial text overlap with arXiv:1604.04702

Considering quantum gravity effect, we investigate the quantum tunneling from high dimensional Kerr-G\"odel black hole using generalized Dirac equation. As a result, revised tunneling probability is obtained, and the corrected Hawking temperature is also presented., Comment: 12 pages, no figures

The forward-backward multiplicity and correlations of target evaporated fragment(black track particle) and target recoiled proton(grey track particle) emitted in 150 A MeV He-emulsion, 290 A MeV C-emulsion, 400 A MeV C-emulsion, 400 A MeV Ne-emulsion and 500 A MeV Fe-emulsion interactions are investigated. It is found that the forward and backward averaged multiplicity of grey, black and heavily ionized track particle increase with the increase of target size. Averaged multiplicity of forward black track particle, backward black track particle, and backward grey track particle do not depend on the projectile size and energy, but the averaged multiplicity of forward grey track particle increases with increase of projectile size and energy. The backward grey track particle multiplicity distribution follows an exponential decay law and the decay constant decreases with increase of target size. The backward-forward multiplicity correlations follow linear law which is independent of the projectile size and energy, and the saturation effect is observed in some heavy target data sets., Comment: 18 pages, 8 figures