High-dispersion spectra of NH2 in the comet C/1999 S4 (LINEAR): Excitation mechanism of the NH2 molecule

Hideyo Kawakita; Jun Ichi Watanabe; Daisuke Kinoshita; Shinsuke Abe; Reiko Furusho; Hideyuki Izumiura; Kenshi Yanagisawa; Seiji Masuda

doi:10.1093/pasj/53.1.l5

High-dispersion spectra of NH₂ in the comet C/1999 S4 (LINEAR): Excitation mechanism of the NH₂ molecule

Hideyo Kawakita, Jun Ichi Watanabe, Daisuke Kinoshita, Shinsuke Abe, Reiko Furusho, Hideyuki Izumiura, Kenshi Yanagisawa, Seiji Masuda

Graduate Institute of Astronomy

Research output: Contribution to journal › Article › peer-review

14 Scopus citations

Abstract

We carried out a high-dispersion spectroscopic observation of the comet C/1999 S4 (LINEAR) on 2000 July 8.75 (UT). The NH₂ Ã(0, 10, 0)-X̃(0, 0, 0) and Ã(0, 9, 0)-X̃(0, 0, 0) bands were extracted from the observed spectrum and compared with the modeled spectra. We developed a fluorescence equilibrium model for the NH₂, in which Ã(0, v′₂, 0)-X̃(0, 0, 0) transitions and the radiative relaxation among the rotational levels in X̃(0, 0, 0) were considered. The rotational structure of the spin doublet (F₁ and F₂ levels) and the Swings effect were considered in the model. The modeled spectra are consistent with the observed spectra of the Ã(0, 10, 0) and Ã(0, 9, 0) bands. Our results show that the fluorescence excitation and the radiative relaxation processes are dominant for NH₂ in a coma of the comet at ∼ 1 AU from the Sun.

Original language	English
Pages (from-to)	L5-L8
Journal	Publications of the Astronomical Society of Japan
Volume	53
Issue number	1
DOIs	https://doi.org/10.1093/pasj/53.1.l5
State	Published - 2001

Keywords

Comets: general
Comets: individual (C/1999 S4: LINEAR)
Molecular processes

Access to Document

10.1093/pasj/53.1.l5

Cite this

@article{6c8002b9a046431eb2b6815506d11243,

title = "High-dispersion spectra of NH2 in the comet C/1999 S4 (LINEAR): Excitation mechanism of the NH2 molecule",

abstract = "We carried out a high-dispersion spectroscopic observation of the comet C/1999 S4 (LINEAR) on 2000 July 8.75 (UT). The NH2 {\~A}(0, 10, 0)-{\~X}(0, 0, 0) and {\~A}(0, 9, 0)-{\~X}(0, 0, 0) bands were extracted from the observed spectrum and compared with the modeled spectra. We developed a fluorescence equilibrium model for the NH2, in which {\~A}(0, v′2, 0)-{\~X}(0, 0, 0) transitions and the radiative relaxation among the rotational levels in {\~X}(0, 0, 0) were considered. The rotational structure of the spin doublet (F1 and F2 levels) and the Swings effect were considered in the model. The modeled spectra are consistent with the observed spectra of the {\~A}(0, 10, 0) and {\~A}(0, 9, 0) bands. Our results show that the fluorescence excitation and the radiative relaxation processes are dominant for NH2 in a coma of the comet at ∼ 1 AU from the Sun.",

keywords = "Comets: general, Comets: individual (C/1999 S4: LINEAR), Molecular processes",

author = "Hideyo Kawakita and Watanabe, {Jun Ichi} and Daisuke Kinoshita and Shinsuke Abe and Reiko Furusho and Hideyuki Izumiura and Kenshi Yanagisawa and Seiji Masuda",

year = "2001",

doi = "10.1093/pasj/53.1.l5",

language = "???core.languages.en_GB???",

volume = "53",

pages = "L5--L8",

journal = "Publications of the Astronomical Society of Japan",

issn = "0004-6264",

number = "1",

}

TY - JOUR

T1 - High-dispersion spectra of NH2 in the comet C/1999 S4 (LINEAR)

T2 - Excitation mechanism of the NH2 molecule

AU - Kawakita, Hideyo

AU - Watanabe, Jun Ichi

AU - Kinoshita, Daisuke

AU - Abe, Shinsuke

AU - Furusho, Reiko

AU - Izumiura, Hideyuki

AU - Yanagisawa, Kenshi

AU - Masuda, Seiji

PY - 2001

Y1 - 2001

N2 - We carried out a high-dispersion spectroscopic observation of the comet C/1999 S4 (LINEAR) on 2000 July 8.75 (UT). The NH2 Ã(0, 10, 0)-X̃(0, 0, 0) and Ã(0, 9, 0)-X̃(0, 0, 0) bands were extracted from the observed spectrum and compared with the modeled spectra. We developed a fluorescence equilibrium model for the NH2, in which Ã(0, v′2, 0)-X̃(0, 0, 0) transitions and the radiative relaxation among the rotational levels in X̃(0, 0, 0) were considered. The rotational structure of the spin doublet (F1 and F2 levels) and the Swings effect were considered in the model. The modeled spectra are consistent with the observed spectra of the Ã(0, 10, 0) and Ã(0, 9, 0) bands. Our results show that the fluorescence excitation and the radiative relaxation processes are dominant for NH2 in a coma of the comet at ∼ 1 AU from the Sun.

AB - We carried out a high-dispersion spectroscopic observation of the comet C/1999 S4 (LINEAR) on 2000 July 8.75 (UT). The NH2 Ã(0, 10, 0)-X̃(0, 0, 0) and Ã(0, 9, 0)-X̃(0, 0, 0) bands were extracted from the observed spectrum and compared with the modeled spectra. We developed a fluorescence equilibrium model for the NH2, in which Ã(0, v′2, 0)-X̃(0, 0, 0) transitions and the radiative relaxation among the rotational levels in X̃(0, 0, 0) were considered. The rotational structure of the spin doublet (F1 and F2 levels) and the Swings effect were considered in the model. The modeled spectra are consistent with the observed spectra of the Ã(0, 10, 0) and Ã(0, 9, 0) bands. Our results show that the fluorescence excitation and the radiative relaxation processes are dominant for NH2 in a coma of the comet at ∼ 1 AU from the Sun.

KW - Comets: general

KW - Comets: individual (C/1999 S4: LINEAR)

KW - Molecular processes

UR - http://www.scopus.com/inward/record.url?scp=0039893844&partnerID=8YFLogxK

U2 - 10.1093/pasj/53.1.l5

DO - 10.1093/pasj/53.1.l5

M3 - 期刊論文

AN - SCOPUS:0039893844

SN - 0004-6264

VL - 53

SP - L5-L8

JO - Publications of the Astronomical Society of Japan

JF - Publications of the Astronomical Society of Japan

IS - 1