Search for CCH -, NCO -, and NCS - negative ions in molecular clouds

Yusuke Morisawa, Hiromichi Hoshina, Yoshiyasu Kato, Zenzo Simizu, Susumu Kuma, Norihito Sogoshi, Mizuho Fushitani, Shiori Watanabe, Yuki Miyamoto, Takamasa Momose, Yasuko Kasai, Kentarou Kawaguchi

Research output: Contribution to journalArticle

15 Citations (Scopus)

Abstract

Despite several suggestions concerning the existence of negatively charged molecules and negative atomic ions in molecular clouds, few attempts have been made to search for negative ions in molecular clouds. In the present study, we extensively searched for three negative molecular ions (CCH -, NCO -, and NCS -) in a dark cloud, L134N, using the Nobeyama 45-m radio telescope. The three negative ions are molecules whose rotational constants have been reported based on laboratory experiments. After a long accumulation, a trace amount of an unidentified emission line was detected at a frequency close to the theoretical prediction of the J = 1-0 transition of CCH -. If this unidentified line is attributable to CCH -, the observed emission intensity would provide an estimation of the column density of CCH - in L134N to be 1.0 × 10 11 cm -2, which corresponds to a fractional abundance of 5 × 10 -12 relative to hydrogen. However, our recent observation using the IRAM 30-m telescope did not reproduce the J = 1-0 signal, nor detect any trace of the J = 2-1 transition. Thus, the identification of CCH - in L134N is not yet confirmed. As for other ions, signals of neither NCO - nor NCS - were detected in L134N. Although we also searched for the three negative ions in a translucent cloud, CB228, and a star-forming region, SgrB2, no signals were detected. The upper limit abundances of the ions in these clouds are discussed.

Original languageEnglish
Pages (from-to)325-334
Number of pages10
JournalPublications of the Astronomical Society of Japan
Volume57
Issue number2
Publication statusPublished - 2005
Externally publishedYes

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molecular clouds
negative ions
ion
ions
radio telescopes
molecular ions
suggestion
molecules
telescopes
stars
hydrogen
predictions
radio
prediction

Keywords

  • ISM: abundances
  • ISM: individual (L134N, CB228, SgrB2)
  • ISM: molecules

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science

Cite this

Morisawa, Y., Hoshina, H., Kato, Y., Simizu, Z., Kuma, S., Sogoshi, N., ... Kawaguchi, K. (2005). Search for CCH -, NCO -, and NCS - negative ions in molecular clouds. Publications of the Astronomical Society of Japan, 57(2), 325-334.

Search for CCH -, NCO -, and NCS - negative ions in molecular clouds. / Morisawa, Yusuke; Hoshina, Hiromichi; Kato, Yoshiyasu; Simizu, Zenzo; Kuma, Susumu; Sogoshi, Norihito; Fushitani, Mizuho; Watanabe, Shiori; Miyamoto, Yuki; Momose, Takamasa; Kasai, Yasuko; Kawaguchi, Kentarou.

In: Publications of the Astronomical Society of Japan, Vol. 57, No. 2, 2005, p. 325-334.

Research output: Contribution to journalArticle

Morisawa, Y, Hoshina, H, Kato, Y, Simizu, Z, Kuma, S, Sogoshi, N, Fushitani, M, Watanabe, S, Miyamoto, Y, Momose, T, Kasai, Y & Kawaguchi, K 2005, 'Search for CCH -, NCO -, and NCS - negative ions in molecular clouds', Publications of the Astronomical Society of Japan, vol. 57, no. 2, pp. 325-334.
Morisawa Y, Hoshina H, Kato Y, Simizu Z, Kuma S, Sogoshi N et al. Search for CCH -, NCO -, and NCS - negative ions in molecular clouds. Publications of the Astronomical Society of Japan. 2005;57(2):325-334.
Morisawa, Yusuke ; Hoshina, Hiromichi ; Kato, Yoshiyasu ; Simizu, Zenzo ; Kuma, Susumu ; Sogoshi, Norihito ; Fushitani, Mizuho ; Watanabe, Shiori ; Miyamoto, Yuki ; Momose, Takamasa ; Kasai, Yasuko ; Kawaguchi, Kentarou. / Search for CCH -, NCO -, and NCS - negative ions in molecular clouds. In: Publications of the Astronomical Society of Japan. 2005 ; Vol. 57, No. 2. pp. 325-334.
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AU - Morisawa, Yusuke

AU - Hoshina, Hiromichi

AU - Kato, Yoshiyasu

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AU - Kuma, Susumu

AU - Sogoshi, Norihito

AU - Fushitani, Mizuho

AU - Watanabe, Shiori

AU - Miyamoto, Yuki

AU - Momose, Takamasa

AU - Kasai, Yasuko

AU - Kawaguchi, Kentarou

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