10min:

R. FUJIMORI, K. KAWAGUCHI, Faculty of Science, Okayama University, Okayama 700-8530, Japan; T. NAKAJIMA, H. OGAWA, Department of Physical Science, Graduate School of Science, Osaka Prefecture University,Osaka 599-8531, Japan.

Watanabe et al. have searched for -alanine in Ori-KL with the Nobeyama 45-m radio telescope. Blagojevic et al. expected that -alanine may have a larger abundance than -alanine in interstellar space. In meteorites the abundance ratio of glycine, -alanine, -alanine is reported to be 1 : 2.35 : 0.26. Pyrimidine may be related to the nucleic acid base such as uracil and searched by Kuan et al. In the present study, we carried out deep searches for -alanine and pyrimidine toward Ori-KL by using a new waveguide-type sideband-separating receiver in the 3 mm band installed at Nobeyama 45-m telescope. Low noise characteristic of the receiver made it possible to high sensitive observation in wide freqency range. The rotational transitions of -alanine and pyrimidine were not detected with upper limit abundances of 2.9×10¹⁴cm^-2, 8.8×10¹²cm^-2, respectivity. The upper limit for pyrimidine is an order of magnitude lower than the previous^ c . Many un-identified lines have been detected and the carriers will be discussed.