Study of baryon number transport dynamics and strangeness conservation effects using Ω-hadron correlations

In nuclear collisions at RHIC energies, an excess of Ω hyperons over ■ is observed, indicating that Ω has a net baryon number despite s and s quarks being produced in pairs. The baryon number in Ω may have been transported from the incident nuclei and/or produced in the baryon-pair production of Ω with other types of anti-hyperons such as Ξ. To investigate these two scenarios, we propose to measure the correlations between Ω and K and between Ω and anti-hyperons. We use two versions, the default and string-melting, of a multiphase transport(AMPT) model to illustrate the method for measuring the correlation and to demonstrate the general shape of the correlation. We present the Ω-hadron correlations from simulated Au+Au collisions at ■ =7.7 and 14.6 Ge V and discuss the dependence on the collision energy and on the hadronization scheme in these two AMPT versions. These correlations can be used to explore the mechanism of baryon number transport and the effects of baryon number and strangeness conservation on nuclear collisions.

Strangeness to increase the density of finite nuclear systems in constraining the high-density nuclear equation of state

As the high-density nuclear equation of state(EOS) is not very well constrained, we suggest that the structural properties from the finite systems can be used to extract a more accurate constraint. By including the strangeness degrees of freedom, the hyperon or anti-kaon, the finite systems can then have a rather high-density core which is relevant to the nuclear EOS at high densities directly. It is found that the density dependence of the symmetry energy is sensitive to the properties of multi-K hypernuclei, while the high-density EOS of symmetric matter correlates sensitively to the properties of kaonic nuclei.

Sigma Terms and Strangeness Contents of Baryon Octet in Modified Chiral Perturbation Theory

In the frame work of chiral perturbation theory, a modified effective Lagrangian for meson-baryon system is constructed, where the SU（3） breaking effect for meson is considered. The difference between physical and chiral limlt decay constants is taken into account. Calculated to one 1ooi） at O（p^3）, the sigma terms and strangeness contents of baryon octet are obtained.

1-4 Strangeness Production in Antiproton Induced Nuclear Reactions.

More localized energy deposition is able to be produced in antiproton-nucleus collisions in comparison withheavy-ion collisions due to annihilation reactions. Searching for the cold quark-gluon plasma (QGP) with antiprotonbeamshas been considered as a hot topic both in experiments and in theretical calculations over the past severaldecades. Strangeness production and hypernucleus formation in antiproton-induced nuclear reactions are importancein exploring the hyperon (antihyperon)-nucleon (HN) potential and the antinucleon-nucleon interaction, whichhave been hot topics in the forthcoming experiments at PANDA in Germany.

Observation of the Z_(cs)(3985) Strange Four-quark Meson:The first hidden-charm tetraquark state with non-zero strangeness

In the March 12.2021 issue of Plvvsical Rerievr Letters.the BES111 collaboration reports the.diseovery of an cxolic multiquark strtture,dubsled Z_(cs)(3985).that is produced in the process of e^(+)e^(-)→K+(D_(s)^(-)D^(*0)+D_(s)^(*-)D^(0))at a e+e center-of-mass cneryof+4.68 GeV.

Strangeness production in pA and AA collisions at 158 A GeV

LUCIAE, a hadronic and string cascade model and its corresponding event generator are used to analyse strangeness production singly and multiply in p-Pb and Pb-Pb collisions at 158 A GeV. Spectra of multiplicity and transverse mass for single $(\Lambda ,\overline \Lambda )$ and multiple $(\Xi ^ - ,\overline {\Xi ^ - } ,\Omega ^ - ,\overline {\Omega ^ - } )$ strangeness are given. In LUCIAE model it suggests a physical mechanism, i.e. the dependence of the strange quark suppression factor on incident energy, projectile mass and centrality of colliding system might result in increase of yield of strange particles with increasing the above three parameters. Calculations from the model reconstruct well the WA97 experimental data: increase of yield of strange particles with increasing centrality and increase of strangeness enhancement with increasing number of strange quarks, in relativistic nucleus-nucleus collisions.

Spectroscopic study of strangeness=-3Ω^(-)baryon

Ω^(-)baryon with sss quarks has been investigated through many theoretical studies so far but scarcely observed in experiments.Here,an attempt has been made to explore properties of Ω with hypercentral Constituent Quark Model(hCQM)with a linear confining term.The resonance mass spectra have been obtained for 1S-4S,1P-4P,1D-3D,and IF-2F.The Regge trajectory has been investigated for the linear nature based on calculated data along with the magnetic moment.The present work has been compared with various approaches and known experimental findings.

Recent results on strangeness,charm and beauty production at HERA

Based on the data collected with the H1 and ZEUS detectors at HERA, recent results on strangeness, charm and beauty production in ep collision are presented.

Precision measurements of strangeness photoproduction at threshold energies with the Crystal Ball at MAMI-C

The photoproduction of K＋ mesons from the nucleon provides important constraints on the nucleon excitation spectrum and at threshold energies challenges effective field theories based on chiral perturbation in the strange quark sector. Preliminary cross-section measurements for γ（P, K＋）A are presented at an unprecedented beam energy resolution. The data was collected at the MAMI-C facility in Mainz using the Crystal Ball Detector. A new method of K＋ detection was used in which the K＋ is tagged from its weak decay products in the detector crystals. This technique has application with other calorimeters at present and future hadron facilities.

The Strangeness Of Sleep

A strange thing happens to nearly everybody at night. They turn off the lights,pull up the covers and close their eyes. Six or seven sleeping hours later,they wake up again.Strange,isn’t it?Sleep puzzles scientists. Scientists and doctors would rather talk about why one can’t fall asleep. They are not sure what causes sleep.

On the Proof of the Contradiction of Set Theory

The article is devoted to proving the inconsistency of set theory arising from the existence of strange trees. All steps of the proof rely on common informal set-theoretic reasoning, but they take into account the prohibitions that were introduced into axiomatic set theories in order to overcome the difficulties encountered by the naive Cantor set theory. Therefore, in fact, the article is about proving the inconsistency of existing axiomatic set theories, in particular, the ZFC theory.

Nuclear dynamics and particle production near threshold energies in heavy-ion collisions

Recent progress of the quantum molecular dynamics model for describing the dynamics of heavy-ion collisions is viewed, in particular the nuclear fragmentation, isospin physics, particle production and in-medium effect, hadron-induced nuclear reactions, hypernucleus, etc.The neck fragmentation in Fermi-energy heavy-ion collisions is investigated for extracting the symmetry energy at subsaturation densities. The isospin effects, in-medium properties, and the behavior of high-density symmetry energy in medium-and high-energy heavy-ion collisions are thoroughly discussed. The hypernuclide dynamics formed in heavy-ion collisions and in hadron-induced reactions is analyzed and addressed in the future experiments at the high-intensity heavy-ion accelerator facility(HIAF).

加拿大纽芬兰省稀有稀土矿化特征与勘查进展

纽芬兰省稀有稀土成矿地质条件优越,矿化主要与侵入的过碱性长英质岩及其喷出岩有关,矿化围岩为中元古代火成岩系,矿床成因类型为岩浆型和热液交代型,且以前者为主,典型矿床为世界级大型原生Strange Lake(Nd-Y-Zr-REE)矿床。目前,地球化学方法是区内寻找稀有稀土矿床最有效的勘探工具,拉布拉多主要勘查区为Letitia Lake、Red Wine Mountains、Flowers River和Strange Lake,纽芬兰岛主要勘查区为Fortune Bay、Clode Sound、Trinity Bay和Lost Pond。

The Origin of the Color Charge into Quarks

Showing the origin of the mass in an additional coupling between field quantum oscillators, we formulate a hypothesis of a geometrical structure of the oscillators of “fields-particles”. In this way, we define the possible structure of quarks and hadrons (as the proton). This hypothesis is reasonable if one admits field oscillators composed by sub-oscillators at semi-quantum (IQuO) and in which a degree of internal freedom is definable. Using the IQuO model, we find the origin of the sign of electric charge in to particles and, in quarks, the isospin, the strangeness and colour charge. Finally, we formulate the structure of the gluons and the variation modality of the colour charge in quarks.

Hard Photons from a Non-Equilibrated Quark-Gluon Plasma with Finite Baryon Density at a Two-Loop Level

We study hard photon production from a two-loop level （bremsstrahlung and annihilation with scattering） in a chemically equilibrating quark-gluon plasma at finite baryon density based on Jüttner distribution of partons of the system. We find that the photon yield from the two-loop level increases obviously with the increasing initial quark chemical potential.

Intelligent Biometric Information Management

We advance here a novel methodology for robust intelligent biometric information management with inferences and predictions made using randomness and complexity concepts. Intelligence refers to learning, adap- tation, and functionality, and robustness refers to the ability to handle incomplete and/or corrupt adversarial information, on one side, and image and or device variability, on the other side. The proposed methodology is model-free and non-parametric. It draws support from discriminative methods using likelihood ratios to link at the conceptual level biometrics and forensics. It further links, at the modeling and implementation level, the Bayesian framework, statistical learning theory (SLT) using transduction and semi-supervised lea- rning, and Information Theory (IY) using mutual information. The key concepts supporting the proposed methodology are a) local estimation to facilitate learning and prediction using both labeled and unlabeled data;b) similarity metrics using regularity of patterns, randomness deficiency, and Kolmogorov complexity (similar to MDL) using strangeness/typicality and ranking p-values;and c) the Cover – Hart theorem on the asymptotical performance of k-nearest neighbors approaching the optimal Bayes error. Several topics on biometric inference and prediction related to 1) multi-level and multi-layer data fusion including quality and multi-modal biometrics;2) score normalization and revision theory;3) face selection and tracking;and 4) identity management, are described here using an integrated approach that includes transduction and boosting for ranking and sequential fusion/aggregation, respectively, on one side, and active learning and change/ outlier/intrusion detection realized using information gain and martingale, respectively, on the other side. The methodology proposed can be mapped to additional types of information beyond biometrics.

一本有新意的微积分教材——评美国MIT教授Strang新编《CALCULUS》

微积分教材数以千计,每年都有不少新作问世,但有新意者却如凤毛麟角。91年夏我到美国参加第二届国际工业与应用数学大会(ICIAM’91),在大会展厅看到美国麻省理工学院(MIT)数学系教授、美国工业与应用数学学会(SIAM)教育委员会主席Strang教授刚刚出版的《CALCULUS》,很有特色,会后应邀访问MIT。

幽默与笑话

Strange Relationships(奇怪的关系)Four best friends met at the hospital since their wives were giving births to their babies.The nurse came up to the first man and said,

多维火焰面求解燃烧场中的多机制火焰结构

火焰面模型已被广泛应用于层流和湍流火焰的模拟中,然而对包含多种火焰机制的复杂燃烧场,针对单一火焰机制的一维层流火焰面模型不能准确地还原其内部的火焰结构特征。为了解决以上问题,基于由Nguyen等提出的多维火焰面生成流形方法(MFM),发展了一种新的交互迭代式Z-C多维火焰面模型。通过层流抬举火焰的模拟,以直接求解详细化学反应的DNS解为参照解,以确定新模型的模化精度,并与一维预混火焰面生成流形方法(premixed FGM)进行了对比。通过对不同模型解的分析可以得出,相比于只能捕捉一种火焰特征的一维火焰面模型,多维火焰面模型可以同时捕捉多机制火焰结构中的扩散和预混特征。使用新的多维火焰面模型求解可以在计算量减小一个数量级的前提下,得到接近DNS参照解的模型精度。