The Luminosity Function of Galaxies as Modeled by a Left Truncated Beta Distribution

• 作者: L. Zaninetti
• 来源期刊: 天文学与天体物理学国际期刊(英文)
• 学科: 地球科学
• 关键词: Galaxies: FUNDAMENTAL Parameters Galaxies: STATISTICS Galaxies: LUMINOSITY Function
• 年，卷（期）: 2014,（1）
• 页码范围: 145-154
• 页数: 10页
• 分类号: P1

摘要

A first new luminosity function of galaxies can be built starting from a left truncated beta probability density function, which is characterized by four parameters. In the astrophysical conversion, the number of parameters increases by one, due to the addition of the overall density of galaxies. A second new galaxy luminosity function is built starting from a left truncated beta probability for the mass of galaxies once a simple nonlinear relationship between mass and luminosity is assumed;in this case the number of parameters is six because the overall density of galaxies and a parameter that regulates mass and luminosity are added. The two new galaxy luminosity functions with finite boundaries were tested on the Sloan Digital Sky Survey (SDSS) in five different bands;the results produce a “better fit” than the Schechter luminosity function in two of the five bands considered. A modified Schechter luminosity function with four parameters has been also analyzed.