Heavy quarkonium spectral function in an anisotropic background
Wen-Bin Chang, Defu Hou
Abstract
In this paper, we use a five-dimensional Einstein-dilaton-two-Maxwell holographic QCD model to investigate the dissociation effects of <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mrow><a:mi>J</a:mi><a:mo>/</a:mo><a:mi mathvariant="normal">Ψ</a:mi></a:mrow></a:math> and <d:math xmlns:d="http://www.w3.org/1998/Math/MathML" display="inline"><d:mi mathvariant="normal">ϒ</d:mi><d:mo stretchy="false">(</d:mo><d:mn>1</d:mn><d:mi>S</d:mi><d:mo stretchy="false">)</d:mo></d:math> states in an anisotropic medium by calculating their spectral functions. First, we present the holographic quarkonium masses at zero temperature via physics-informed neural networks. Then, at a finite temperature, we derive the spectral functions, representing heavy vector mesons as peaks, and observe that with increasing anisotropy, temperature, chemical potential, and warp factor, the peak height diminishes while its width expands, indicating an accelerated dissociation process. Additionally, the results indicate the anisotropy induces a stronger dissociation effect in the direction parallel to the polarization compared to the perpendicular, revealing the anisotropy’s directional influence. Published by the American Physical Society 2024