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

Infrared absorption band at 7 mum of protostar dusts- An explanation with magnesium

Research Project

Project/Area Number 07804014
Research Category

Grant-in-Aid for Scientific Research (C)

Allocation TypeSingle-year Grants
Section一般
Research Field Astronomy
Research InstitutionThe University of Electro-Gommunications

Principal Investigator

WADA Setsuko  The Univ.of Electro-Communications, Faculty of Electro-Communications Research Associate, 電気通信学部, 助手 (30017404)

Co-Investigator(Kenkyū-buntansha) NARISAWA Takatoshi  The Univ.of Electro-Communications, Center for Instrumental Analysis Research As, 機器分析センター, 助手 (30143712)
Project Period (FY) 1995 – 1996
Project Status Completed (Fiscal Year 1996)
Budget Amount *help
¥1,900,000 (Direct Cost: ¥1,900,000)
Fiscal Year 1996: ¥700,000 (Direct Cost: ¥700,000)
Fiscal Year 1995: ¥1,200,000 (Direct Cost: ¥1,200,000)
KeywordsInterstellar Dust / Circumstellar Dust / Infrared Absorption Spectrum / Car bonate / Dark Cloud / Protostar / 赤外線スペクトル / 塵
Research Abstract

An infrared absorption band at a wavelength of 7 mum was observed in embedded protostars. Differences of the band width are seen in these objects. Up to now, various materials are proposed to the origin of the band, i.e., hydrocarbons, methanol, photolyzed mixtures of CO_2, H_2, NH_3 etc, and carbonates. We examined again infrared absorption bands of carbonate materials, pure carbonate, and mixtures of carbonate with oxides and hydroxides.
Pure MgCO_3 and FeCO_3 show a peak at 6.83-6.85mum and 6.93-6.94mum, respectively. The features are very similar tothe 7 mum band shape observed in W33A,however these carbonates show additional subpeaks around 11mum region, which have not observed in protostars.
We synthesized carbonate-oxide-hydroxide mixtures by (1) grinding oxides in CO_2 atmosphere, and (2) heating of magnesium carbonate hydroxide under vacuum. The products show a very broad band around 7 mum which is matched to the band observed in Mon R2 #2. In addition, the peak height of the subpeaks around 11mum of these materialsare very small.
The main result is summarized as follows. Carbonates are good candidates for the 7 mum band of protostars though their spectra have some additional bands.

Report

(3 results)
  • 1996 Annual Research Report   Final Research Report Summary
  • 1995 Annual Research Report

URL: 

Published: 1995-04-01   Modified: 2016-04-21  

Information User Guide FAQ News Terms of Use Attribution of KAKENHI

Powered by NII kakenhi