Rupak Gautam
Institute for Nuclear Theory, University of Washington, Seattle, Washington 98195, USA.
Phys Rev Lett. 2007 Mar 2;98(9):090403. doi: 10.1103/PhysRevLett.98.090403.
Thermodynamic properties of a Fermi system close to the unitarity limit, where the 2-body scattering length a approaches +/-infinity, are studied in the high temperature Boltzmann regime. For dilute systems the virial expansion coefficients in the Boltzmann regime are expected, from general arguments, to be universal. A model independent finite temperature T calculation of the third virial coefficient b3(T) is presented. At the unitarity limit, b3infinity approximately 1.11 is a universal number. The energy density up to the third virial expansion is derived. These calculations are of interest in dilute neutron matter and could be tested in current atomic experiments on dilute Fermi gases near the Feshbach resonance.
在高温玻尔兹曼区域研究了接近幺正极限的费米系统的热力学性质，在该极限下两体散射长度a趋近于正无穷或负无穷。对于稀薄系统，从一般理论来看，玻尔兹曼区域的维里展开系数应是普适的。给出了一个与模型无关的有限温度T下第三维里系数b3(T)的计算。在幺正极限下，b3∞约为1.11是一个普适数。推导了直至第三维里展开的能量密度。这些计算对于稀薄中子物质很有意义，并且可以在当前关于接近费什巴赫共振的稀薄费米气体的原子实验中进行检验。
