Infrared Observation of Galactid Halo

1996 Fiscal Year Final Research Report Summary

• Project/Area Number: 06402002
• Research Category: Grant-in-Aid for Scientific Research (A)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Astronomy
• Research Institution: The Institute of space and Astronautical Science (1996); Nagoya University (1994-1995)
• Principal Investigator: MATSUMOTO Toshio Research Division for Space Astrophysics, 宇宙圏研究系, 教授 (60022696)
• Co-Investigator(Kenkyū-buntansha): MATSUHARA Hideo Nagoya Universtiy, the Dept.of Science, 理学部, 助手 (30219464) ; KAWADA Mitsunobu ISAS Research Division for Space Astrophysics, 宇宙圏研究系, 助手 (50280558) ; NAKAGAWA Takao ISAS Research Division for Space Astrophysics, 宇宙圏研究系, 助手 (20202210) ; SHIBAI Hiroshi ISAS Research Division for Basic Space Science, 共通基礎研究系, 助教授 (70154234) ; MURAKAMI Hiroshi ISAS Reseach Division for Space Astrophysics, 宇宙圏研究系, 助教授 (40135299)
• Project Period (FY): 1994 – 1996
• Keywords: Infrared Astronomy / Dark matter / Rocket experiment / Infrared Imaging

Research Abstract

Dark matter in the Universe is one of the most important topics of the modern astronomy. The purpose of this research is to find the contribution of low mass stars to the galactic dark matter.
The rocket payload was developed under the collaboration with US people. The rocket experiments were carried out on June 1996 and May 1997 at White Sands with using sounding rocket of NASA.The first infrared image of the external galaxy NGC4565 was successfully obtained.
The obtained data were analyzed carefully, and following new results were delineated.
The extended emission component was detected over 5'from the center. This emission component shows r^<-3.6> dependence that is different from r^<-1> dependence expected from the flat rotation curve. By comparing with mass distribution estimated from the rotation curve, lower limit of ^- 300 was obtained for the mass to luminosity ration, M/L,at 3.5-5mum. This value indicates that ordinary stars can not be dark matter and brown dwarfs are likely to be origin of the dark matter if dark matter consists of point sources.
On the other hands, recent experiments of MACHO indicate that the mass of MACHO is ^-0.5M_0 (not less than 0.10.1M_0) and half of the dark matter can be explaened by MACHO.
The possible candidates of the dark matter that iare consistent both with MACHO experimints and our result are now white dwarfs and black holes, although their origins are still remaind to be problems.

Research Products

• [Publications] J.J.Bock, T.Matsumoto 他: "Rocket-bome instrument to seach for Infrared emission from baryonic dark matter in galactic halos" Proceedings of the SPIE International synposium on Astronomical telescope and Instrumention. (1998)
  • Description: 「研究成果報告書概要(和文)」より
• [Publications] T.Matsumoto, M.Kawada 他: "Rocket Observation of the Near Infrared Halo of NGC 4565" Proceedings of the International synposium "Origin and Evolution Matters and Galaxies. (1998)
  • Description: 「研究成果報告書概要(和文)」より
• [Publications] J.J Bock, M.Kawada, A.E.Lange, T.Matsumoto K.Uemizu, T.Watabe, S.A.Sarah, G.G.Fazio, W.J.Forrest. , J.L.Pipher, and D.Price.: ""Rocket-bome instrument to serach for infrared emission from baryonic dark matter in galactic halos"" Proceedings of the SPIE International Symposium on Astronomical telescopes and Instrumentation. (in press). (1998)
  • Description: 「研究成果報告書概要(欧文)」より
• [Publications] T.Matsumoto, J.J.Bock, M.Kawada, A.E.Lange, K.Uemizu, T.Watabe, S.A.Sarah, G.G.Fazio, W.J.Forrest, J.L.Pipher, and D.Price.: ""Rockt observation of the Near Infrared Halo of NGC 4565"" Proceedings of the International Symposium "Origin and Evolution of Matters and Galaxies". (in press). (1998)
  • Description: 「研究成果報告書概要(欧文)」より