SUPERNOVA SEARCH IN EARLY TYPE GALAXIES

我们与位于日本的7个公共天文观测台一起建立了一个项目，通过监测每个包含一个星系团的1030个场来搜索早期星系中的超新星。该项目使用的望远镜孔径从60厘米到1米不等。不幸的是，并没有发现超新星。相反，发现了一颗自行很大的星星。我们开发了一个计算机程序，可以自动探测新出现的天体。我们中的一个（Doi，M.）他在用SUBARU进行远距离超新星观测时使用了这个程序。这次调查发现了130个候选对象。在理论上，我们提出了一个解释M87周围存在热气体的模型，即来自室女座星系团内部较热物质的热传导通量阻止了气体被强辐射冷却。我们还发展了一个星系星星形成历史的模型，假设大多数恒星是由超新星卷起的物质形成的。该模型再现了银河晕和某些局部矮球状星系的星星形成历史。

We have constructed a project with 7 public astronomical observatories located in Japan to search supernovae in early type galaxies by monitoring 〜30 fields each of which contains a cluster of galaxies. The apertures of telescopes used in this project range from 60 cm to 1 m. Unfortunately, no supernova has been found. Instead, a star with a large proper motion was found.We have developed a computer program to automatically detect newly emerging celestial objects. One of us (Doi, M.) utilized this program when he performed an observation for distant supernova survey with SUBARU. This survey found 〜30 candidate objects. The spectra for 7 of this candidates were taken with FOCAS and it was found that they are actually type la supemovae.As for theoretical attempts, we have proposed a model to explain the existence of hot gas surrounding M87 in which the conductive heat flux from the hotter intra-cluster matter of the Virgo cluster prevent the gas from being cooled by intense radiation. We have also developed a model for star formation history of galaxies assuming most of stars were formed from the matter swept up by supernovae. This model reproduces star formation histories of the Galactic halo and some local dwarf spheroidal galaxies.