标题： 极环星系和塔利-费舍尔关系：对暗晕形状的影响 显示英文标题

标题： Polar Ring Galaxies and the Tully Fisher relation: implications for the dark halo shape

摘要： 我们研究了极环星系(PRGs)的Tully-Fisher关系，基于这些特殊天体的近红外、光学和HI数据。总K波段光度，主要来自中心宿主星系，以及在峰值线流量密度20%处测量的HI线宽，这反映了极平面中的势场，将样本中的大多数极环置于螺旋星系定义的Tully-Fisher关系之外，许多PRGs显示出比观测到的K波段光度预期更大的HI线宽。这一结果通过基于B波段数据的更大样本得到确认。这一观测证据可能与这些系统中的暗晕形状和取向有关，我们通过PRG形成和动力学的数值模拟来研究：在PRGs中观察到的较大旋转速度可以通过与极环对齐的扁平极晕来解释。 显示英文摘要

摘要： We have investigated the Tully-Fisher relation for Polar Ring Galaxies (PRGs), based on near infrared, optical and HI data available for a sample of these peculiar objects. The total K-band luminosity, which mainly comes from the central host galaxy, and the measured HI linewidth at 20% of the peak line flux density, which traces the potential in the polar plane, place most polar rings of the sample far from the Tully-Fisher relation defined for spiral galaxies, with many PRGs showing larger HI linewidths than expected for the observed K band luminosity. This result is confirmed by a larger sample of objects, based on B-band data. This observational evidence may be related to the dark halo shape and orientation in these systems, which we study by numerical modeling of PRG formation and dynamics: the larger rotation velocities observed in PRGs can be explained by a flattened polar halo, aligned with the polar ring.