PaperPanorama

Nuclear Theory·nucl-th

Wednesday·December 13, 2017

8 papers5 primary·3 cross-listed

  1. 06

    Strangeness Production in low energy Heavy Ion Collisions via Hagedorn Resonances

    K. Gallmeister🇩🇪 · M. Beitel🇩🇪 · C. Greiner🇩🇪

    A novel, unorthodox picture of the dynamics of heavy ion collisions is developed using the concept of Hagedorn states. A prescription of the bootstrap of Hagedorn states respecting the conserved quantum numbers baryon number B, strangeness S, isospin I is implememted into the GiBUU transport model. Using a strangeness saturation suppression factor suitable for nucleon-nucleon-collisions, recent experimental data for the strangeness production by the HADES collaboration in Au+Au and Ar+KCl is reasonable well described. The experimental observed exponential slopes of the energy distributions are nicely reproduced. Thus, a dynamical model using Hagedorn resonance states, supplemented by a strangeness saturation suppression factor, is able to explain essential features (multiplicities, exponential slope) of experimental data for strangeness production in nucleus-nucleus collisions close to threshold.

    hep-phhep-exnucl-thPRC(2018)·13 citations
  2. 07

    World-line formulation of chiral kinetic theory in topological background gauge fields

    Niklas Mueller🇺🇸 · Raju Venugopalan🇺🇸

    In heavy-ion collisions, an interesting question of phenomenological relevance is how the chiral imbalance generated at early times persists through a fluctuating background of sphalerons in addition to other "non-anomalous" interactions with the QGP. To address this question, we construct a relativistic chiral kinetic theory using the world-line formulation of quantum field theory. We outline how Berry's phase arises in this framework, and how its effects can be clearly distinguished from those arising from the chiral anomaly. We further outline how this framework can be matched to classical statistical simulations at early times and to anomalous chiral hydrodynamics at late times.

    hep-phhep-thnucl-thPoS(2018)·4 citations
  3. 08

    A Subleading Power Operator Basis for the Scalar Quark Current

    Cyuan-Han Chang🇺🇸 · Iain W. Stewart🇺🇸 · Gherardo Vita🇺🇸

    Factorization theorems play a crucial role in our understanding of the strong interaction. For collider processes they are typically formulated at leading power and much less is known about power corrections in the expansion. Here we present a complete basis of power suppressed operators for a scalar quark current at in the amplitude level power expansion in the Soft Collinear Effective Theory, demonstrating that helicity selection rules significantly simplify the construction. This basis applies for the production of any color singlet scalar in annihilation (such as ). We also classify all operators which contribute to the cross section at and perform matching calculations to determine their tree level Wilson coefficients. These results can be exploited to study power corrections in both resummed and fixed order perturbation theory, and for analyzing the factorization properties of gauge theory amplitudes and cross sections at subleading power.

    hep-phnucl-thJHEP(2018)·43 citations

Affiliations

first authorsco-authorsvia INSPIRE