The Hubble constant as derived from 21 cm linewidths
The Hubble constant as derived from 21 cm linewidths
复制标题
从 21 厘米线宽得出的哈勃常数
作者：
A. Sandage;G. Tammann
红外21厘米线宽-绝对星等关系是利用已知距离的本星系，包括M33和M81的新距离测定值进行校准的。校准后的关系式应用于17个Sab到Sd型的室女座星系团，得到的星系团模数为（m-M）0室女座= 31.47±0.34。可靠的相对距离指标被用来将距离尺度扩展到后发座星系团，发现后发座星系团的距离模数为（m-M）0 Coma = 35.39±0.35。蓝色的21厘米线宽-绝对星等关系给出了稍大的距离。结合这两种方法，在后发座星系团的距离上，哈勃常数为H 0 =55±9 km s−1 Mpc−1。这个值与H 0 = 50±7 km s−1 Mpc−1的整体值相一致，给出了哈勃时间Ho−1 = 19.5×103 Myr，与化学元素的年龄和我们银河系的年龄相一致，从球状星团确定。
The IR 21 cm linewidth–absolute magnitude relation is calibrated by means of local galaxies with known distances, including new distance determinations of M33 and M81. The calibrated relation is applied to 17 Virgo cluster galaxies of type Sab to Sd and yields a cluster modulus of (m−M)0Virgo = 31.47±0.34. Reliable relative distance indicators are used to extend the distance scale to the Coma cluster, for which a distance modulus is found of (m−M)0Coma = 35.39±0.35. The blue 21 cm linewidth–absolute magnitude relation gives slightly larger distances. A combination of the two methods leads to a Hubble constant at the distance of the Coma cluster of H0=55±9 km s−1 Mpc−1. This value agrees with the global value of H0 = 50±7 km s−1 Mpc−1, giving a Hubble time of Ho−1 = 19.5×103 Myr, in aggreement with the age of the chemical elements and with the age of our Galaxy, determined from globular clusters.