Radiative hadronization: Photon emission at hadronization from quark-gluon plasma
Radiative hadronization: Photon emission at hadronization from quark-gluon plasma
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DOI：
10.1103/physrevc.106.034906
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发表时间：
2022-04
影响因子：
3.1
通讯作者：
H. Fujii;K. Itakura;Katsunori Miyachi;C. Nonaka
中科院分区：
文献类型：
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作者：
H. Fujii;K. Itakura;Katsunori Miyachi;C. Nonaka
我们研究了相对论重离子碰撞中产生的夸克胶子等离子体在强子化阶段的光子发射。一个复合模型的图像表明，一个夸克和一个反夸克在强子化中束缚成一个介子态，如果没有其他的东西，这显然违反了能量守恒。我们在这里考虑强子化过程中的重组伴随着光子发射。这是等离子体物理学中已知的“辐射复合”的模拟，例如e − + p + → H 0 + γ，当电磁等离子体回到中性原子气体时发生。“辐射强子化”图像将导致（i）光子产额的增强，（ii）类似于强子的光子的显著减少，以及（iii）具有热分布的光子横动量（p T）分布，其有效温度由夸克的蓝移温度给出。作为辐射强子化的一个最简单的唯象实现，我们修改了复合模型，引入了光子发射，并用这个修改后的艾德模型计算了光子产额。将该贡献加入到直接光子产额中，沿着加入用流体动力学模型计算的热光子贡献和参数化的瞬发光子贡献，我们研究了RHIC和LHC能区重离子碰撞中产生的光子的p-T谱和椭圆流.
We investigate photon emission at the hadronization stage from a quark-gluon plasma created in relativistic heavy-ion collisions. A recombination-model picture suggests that a quark and an antiquark bound into a meson state in hadronization, which would apparently violate the energy conservation if there is nothing else involved. We consider here a hadronization process where the recombination accompanies a photon emission. This is an analog of the “ radiative recombination ” known in plasma physics, such as e − + p + → H 0 + γ , which occurs when an electromagnetic plasma goes back to a neutral atomic gas. The “radiative hadronization” picture will bring about (i) an enhancement of the photon yield, (ii) significant flow of photons similar to that of hadrons, and (iii) the photon transverse momentum ( p T ) distribution with a thermal profile whose effective temperature is given by blue-shifted temperature of quarks. Here as a simplest and phenomenological realization of the radiative hadronization, we modify the recombination model to involve a photon emission and evaluate the photon yield with this modified model. Adding this contribution to the direct photon yield along with thermal photon contribution calculated with a hydrodynamic model and a parametrized contribution of prompt photons, we study the p T spectrum and elliptic flow of the photons produced in heavy-ion collisions at RHIC and LHC energies.