• Search Research Projects
  • Search Researchers
  • How to Use
  1. Back to project page

2003 Fiscal Year Final Research Report Summary

Research on Outburst Mechanisms of Dwarf Novae and Evolution of Cataclysmic Variable Stars

Research Project

Project/Area Number 12640237
Research Category

Grant-in-Aid for Scientific Research (C)

Allocation TypeSingle-year Grants
Section一般
Research Field Astronomy
Research InstitutionNagasaki University

Principal Investigator

OSAKI Yoji  Nagasaki University, Faculty of Education, Professor, 教育学部, 教授 (30011547)

Project Period (FY) 2000 – 2003
KeywordsDwarf Novae / Cataclysmic Variables / Accretion Disks / Close Binary Systems / Instabilities / Superhumps / WZ Sge stars / Tomography
Research Abstract

Yoji Osaki, the head investigator, proposed a unification model for dwarf nova outbursts within the basic framework of the disk instability model in 1996. My research is basically a continuation along this line. My research results in 2002-2003 are summarized below. (1) We have proposed a new model to explain repetitive rebrightemng in WZ Sge stars. (2) We have proposed that the "early hump" phenomenon observed in the early phase of outbursts of WZ Sge stars is, the manifestation of the tidal 2:1 resonance in accretion disks of binary systems with extremely low mass ratios. (3) We have critically examined observational evidence for enhanced mass transfer from the secondary star during outbursts and demonstrated that most evidence for enhanced mass transfer is not well substantiated. (4) I have proposed a new method for analyzing complex superhump light curves for the 2001 outburst of WZ Sge. This method is called a helical tomography of an accretion disk because it can reconstruct a series of disk images at different superhump period.

  • Research Products

    (12 results)

All Other

All Publications (12 results)

  • [Publications] Y.Osaki: "Dwarf Nova and Accretion Disks"Astrophysical Ages and Time Scales (PASP conference Series). 245. 57-64 (2001)

    • Description
      「研究成果報告書概要(和文)」より
  • [Publications] Y.Osaki, F.Meyer, E.Meyer-Hofmeister: "Repetitive rebrightening of EG Cancri : Evidence for viscosity decay in the quiescent disk"Astronomy & Astrophysics. 370. 488-495 (2001)

    • Description
      「研究成果報告書概要(和文)」より
  • [Publications] Y.Osaki, F.Meyer: "Early Humps in WZ Sge Stars"Astronomy & Astrophysics. 383. 574-579 (2002)

    • Description
      「研究成果報告書概要(和文)」より
  • [Publications] Y.Osaki, F.Meyer: "Is evidence for enhanced mass transfer during dwarf-nova outbursts well substantiated?"Astronomy & Astrophysics. 401. 841-848 (2003)

    • Description
      「研究成果報告書概要(和文)」より
  • [Publications] Yoji Osaki: "Helical Tomography of an Accretion Disk by Superhump Light Curves of the 2001 Outburst of WZ Sagittae"Publications of Astronomical Society of Japan. 55. 841-848 (2003)

    • Description
      「研究成果報告書概要(和文)」より
  • [Publications] 尾崎 洋二: "星はなぜ輝くのか"朝日新聞社. 258 (2002)

    • Description
      「研究成果報告書概要(和文)」より
  • [Publications] Y.Osaki, F.Meyer, E.Meyer-Hofineister: "Repetitive rebrightening of EG Cancri : Evidence for viscosity decay in the quiescent disk?"Astron.Astrophys.. 370. 488-495 (2001)

    • Description
      「研究成果報告書概要(欧文)」より
  • [Publications] Y.Osaki, F.Meyer: "Early Humps in WZ Sge stars"Astron.Astrophys.. 383. 574-579 (2002)

    • Description
      「研究成果報告書概要(欧文)」より
  • [Publications] Y.Osaki, F.Meyer: "Is Evidence for Enhanced Mass Transfer During Dwarf Nova Outburst Well Substantiated?"Astron.Astrophys.. 401. 325-337 (2003)

    • Description
      「研究成果報告書概要(欧文)」より
  • [Publications] Y.Osaki: "Helical Tomography of an Accretion Disk by Superhump Light Curves of the 2001 Outburst of WZ Sagittae"Publ.Astron.Soc.Japan. 55. 841-848 (2003)

    • Description
      「研究成果報告書概要(欧文)」より
  • [Publications] Y.Osaki eds.T.von Hipp.el, C.Simpson, N.Manset): "Dwarf Nova and Accretion Disks"Astrophysical Ages and Tine Scales, ( (PASP Conference Series, 245, San Francisco). 57-64 (2001)

    • Description
      「研究成果報告書概要(欧文)」より
  • [Publications] Y.Osaki: "Why do stars shine?(a book written in Japanese)"Asahi-Shinbun-sha. 258 (2002)

    • Description
      「研究成果報告書概要(欧文)」より

URL: 

Published: 2005-04-19  

Information User Guide FAQ News Terms of Use Attribution of KAKENHI

Powered by NII kakenhi