1 / 11

Chiral Susceptibility Analysis in Effective Interaction Model

This presentation by Min He at the CCAST Workshop in March 2008 delves into the study of chiral susceptibility within the context of Quantum Chromodynamics (QCD) and its phases. The approach discussed includes analytical derivation and the application of the Dyson-Schwinger equation coupled with Bethe-Salpeter equation methodologies. Key findings reveal a pronounced divergent peak indicative of a second-order phase transition at a critical temperature of 150 MeV. The research identifies a significant disconnected part in the susceptibility, free from quadratic divergence, contributing to the understanding of chiral symmetry restoration in two-flavor systems.

suchi
Télécharger la présentation

Chiral Susceptibility Analysis in Effective Interaction Model

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Chiral Susceptibility in an Effective Interaction Model 南京大学物理系 何 敏 导师 宗红石 CCAST_Workshop Mar. 2008 Min He @ NJU

  2. Outline • Introduction ---- QCD and its phases ---- Chiral suscept. : lattice studies • Our approach ---- Analytical derivation ---- DSE-BSE treatment and result • Summary CCAST_Workshop Mar. 2008 Min He @ NJU

  3. QCD Phase Diagram (m_q\=0)---from M.Stephanov CCAST_Workshop Mar. 2008 Min He @ NJU

  4. QCD Phase Diagram(m_q=0) ---from M.Stephanov CCAST_Workshop Mar. 2008 Min He @ NJU

  5. Chiral Suscept.:Lattice Study Nature 443,675(2006) (1) No volume-dependent peak height is observed at physical quark mass (2) This implies an analytic crossover, rather than a true transition CCAST_Workshop Mar. 2008 Min He @ NJU

  6. Our Analytical Approach Chiral suscpt. Adopting the identities we arrive at The finite temperature version reads CCAST_Workshop Mar. 2008 Min He @ NJU

  7. Identification of Disconnected Part # Quadratic divergence # Dirac operator formulation ---The first two parts constitute the disconnected part, --- Measure the fluctuation of order parameter --- It is this part that is of direct physical relevance and interest # Connected part # Disconnected part : free from quadratic divergence CCAST_Workshop Mar. 2008 Min He @ NJU

  8. DSE-BSE Treatment # Rainbow-DSE for quark propagator # Ladder-BSE for dressed scalar vertex # A seperable, ultravioletly finite model gluon propagator CCAST_Workshop Mar. 2008 Min He @ NJU

  9. Numerical Result The disconnected chiral susceptibility # A narrow,pronounced divergent peak is observed # This is a characteristic of a phase transition of 2nd order # The transition temperature T_c=150 Mev CCAST_Workshop Mar. 2008 Min He @ NJU

  10. Summary # A model independent, closed integral formula for chiral suscept. is derived, which expresses the latter in terms of basic QFT objects: dressed propagator and vertex. # Its physically relevant disconnected part is identified, which suffers from no quadratic divergence and arises from the scalar vertex correction by non-perturbative effects. # This is then illustrated by a model calculation based on rainbow-DSE ladder-BSE with an effective seperable model gluon propagator. # A phase transition of 2nd order driven by chiral symmetry restoration is established for two flavors in the chiral limit. CCAST_Workshop Mar. 2008 Min He @ NJU

  11. Thank You ! CCAST_Workshop Mar. 2008 Min He @ NJU

More Related