标题： 双星系统中巨星的旋转速度：I. D'型共生星 显示英文标题

标题： Rotational velocities of the giants in symbiotic stars: I. D'-type symbiotics

摘要： 我们使用交叉相关函数方法测量了若干D'型共生星的质量供体的旋转速度(v.sini)。 在已知v.sini的五个D'型共生星中，有四个看起来比相应光谱类型的v.sini目录中的值要快得多。 其中至少有三个恒星的旋转速度达到了临界速度的相当大一部分(>=0.5)。 这意味着在D'型共生星中，冷组分的旋转速度比孤立的巨星更快。 如果这些双星是同步的，它们的轨道周期应该相对较短(4-60天)。 我们还简要讨论了快速旋转的可能起源及其与质量损失和尘埃形成的关系。 显示英文摘要

摘要： We have measured the rotational velocities (v.sini) of the mass donors in a number of D'--type symbiotic stars, using the cross-correlation function method. Four from five D' symbiotic stars with known v.sini, appeared to be very fast rotators compared with the catalogues of v.sini for the corresponding spectral types. At least three of these stars rotate at a substantial fraction (>=0.5) of the critical velocity. This means that at least in D'-type symbiotics the cool components rotate faster than isolated giants. If these binary stars are synchronized, their orbital periods should be relatively short (4-60 days). We also briefly discuss the possible origin of the rapid rotation and its connection with mass loss and dust formation.