267 research outputs found
Correlation in Relativistic Heavy Ion Collisions with Nucleon-Hyperon Interaction from Lattice QCD
On the basis of the interaction extracted from (2+1)-flavor lattice
QCD simulations at the physical point, the momentum correlation of and
produced in relativistic heavy ion collisions is evaluated. defined by a ratio of the momentum correlations between the systems
with different source sizes is shown to be largely enhanced at low momentum due
to the strong attraction between and in the channel. Thus,
measuring this ratio at RHIC and LHC and its comparison to the theoretical
analysis will give a useful constraint on the interaction.Comment: 4 pages, 2 figures; proceedings contribution for Quark Matter 201
Net baryon number fluctuations across the chiral phase transition at finite density in the strong coupling lattice QCD
We investigate the net-baryon number fluctuations across the chiral phase
transition at finite density in the strong coupling and chiral limit. Mesonic
field fluctuations are taken into account by using the auxiliary field
Monte-Carlo method. We find that the higher-order cumulant ratios,
and , show oscillatory behavior around the phase boundary at
, and there exists the region where the higher-order cumulant
ratios are negative. The negative region of is found to shrink
with increasing lattice size. This behavior agrees with the expectations from
the scaling analysis.Comment: 16 pages, 5 figure
U_A(1) Anomaly in Hot and Dense QCD and the Critical Surface
We discuss the chiral phase transition in hot and dense QCD with three light
flavors. Inspired by the well known fact that the U_A(1) anomaly could induce
first order phase transitions, we study the effect of the possible restoration
of the U_A(1) symmetry at finite density. In particular, we explore the link
between the U_A(1) restoration and the recent lattice QCD results of de
Forcrand and Philipsen, in which the first order phase transition region near
zero chemical potential (mu) shrinks in the quark mass and mu space when mu is
increased. Starting from the Ginzburg-Landau theory for general discussions, we
then use the Nambu--Jona-Lasinio model for quantitative studies. With the
partial U_A(1) restoration modeled by the density dependent 't Hooft
interaction, we fit the shrinking of the critical surface found in de Forcrand
and Philipsen's lattice calculation at low mu. At higher mu, the critical
surface might shrink or expand, depending on the scenarios. This raises the
possibility that despite the shrinking of the critical surface at lower mu, the
QCD critical end point might still exist due to the expansion at higher mu. In
this case, very high precision lattice data will be needed to detect the
back-bending of the critical surface with the currently available analytic
continuation or Taylor expansion approaches. Lattice computations could,
however, test whether the U_A(1) restoration is responsible for the shrinking
of the critical surface by computing eta' mass or the topological
susceptibility at small mu.Comment: 8 pages, 5 figure
Sigma meson in QCD sum rules using a two quark current with derivatives
We study the meson in QCD sum rules using a two quark interpolating
field with derivatives. In the constituent quark model, the meson is
composed of a quark and an antiquark in the relative p-wave state and is thus
expected to have a larger overlap with an interpolating field that measures the
derivative of the relative quark wave-function. While the sum rule with a
current without derivatives gives a pole mass of around 1 GeV, the present sum
rule with a derivative current gives a mass of around 550 MeV and a width of
400 MeV, that could be identified with the meson.Comment: 4 pages, 2 figure
Diphyllobothriasis Associated with Eating Raw Pacific Salmon
This tapeworm disease is changing from one of rural populations to one of urban populations worldwide
A neural demodulator for quadrature amplitude modulation signals
金沢大学理工研究域電子情報学系A neural demodulator is proposed for quadrature amplitude modulation (QAM) signals. It has several important features compared with conventional linear methods. First, necessary functions for the QAM demodulation, including wide-band noise rejection, pulse waveform shaping, and decoding, can be embedded in a single neural network. This means that these functions are not separately designed but are unified in a learning process. Second, these functions can be self-organized through the learning. Supervised learning algorithms, such as the back-propagation algorithm, can be applied for this purpose. Finally, both wide-band noise rejection and a very sharp waveform response can be simultaneously achieved. It is very difficult to be done by linear filtering. Computer simulation demonstrates efficiency of the proposed method
Femtoscopic study of coupled-channel baryon-baryon interactions with
Particles and Nuclei International Conference - PANIC2021, 5 - 10 September, 2021, OnlineThe correlation functions of pΞ− and ΛΛ pairs from pp and pA collisions are studied in the coupled-channel framework using the NΞ-ΛΛ coupled-channel baryon-baryon potentials obtained in the lattice QCD calculation at almost physical quark masses. The pΞ− correlation function is calculated to be significantly enhanced from the pure Coulomb case, while the ΛΛ correlation function is slightly enhanced from that of the pure fermion quantum statistics. These features reflect the large and small scattering lengths in the pΞ− and ΛΛ channels in magnitude, and agree with the observed data by the ALICE collaboration. The agreement confirms the S = −2 baryon-baryon potentials from lattice QCD
エイキュウ ジシャク ドウキ デンドウキ ノ イチ センサレス クドウ ニ カンスル ジッショウ シケン ケンキュウ
The PM motor has become increasingly popular for many applications. We proposed a novel sensor-less control system for the PM motor drive. The proposed system can be easily constructed without any motor parameters. We developed the prototype electric vehicle (EV) driven by interior permanent magnet synchronous motor using proposed sensor-less control methods . In this paper, we describe the principle of operation of the proposed sensorless control scheme for the PM motor drive and we apply this control method to the main motor drive for EV and reports test run result of the electric vehicle, using proposed sensor-less control methods
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