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June 19, 2012 (Toho Univ. a, Univ. Toyama b ) ○Yuta Motoki a, Yukari Tsunoda a, Hiroyuki Ozeki a, Kaori Kobayashi b Hiroyuki Ozeki a, Kaori Kobayashi b
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Glycine (NH 2 CH 2 COOH) Alanine, Glutamine, etc… Amino acid ProteinLife Freq.(GHz)Speace Detect ? Brown et al. (1979) 23 - 83 Sgr B2, Ori A, etc. × Hollis et al. (1980) 80 - 100 Sgr B2 × Combes et al. (1996) 101 - 223 Sgr B2, Orion × Ceccarelli et al. (2000) 101, 216 IRAS 16293 - 2422 × Kuan et al. ( 2003 ) 79 - 251 Sgr B2, Ori KL, W51 e1/e2 ? Etc.
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Kuan et al. reported detection of glycine of total 27 lines towards Sgr B2, Orion KL, W51 e1/e2. towards Sgr B2, Orion KL, W51 e1/e2. After that, Snyder et al. (2005) contradicted it ・ ・・ New spectra data of glycine. Unpublished astronomical observational data. Other observational data. They concluded that part of these glycine lines are due to the vibrational-excited state of are due to the vibrational-excited state of ethyl cyanide(CH 3 CH 2 CN) or vinyl cyanide(CH 2 CHCN).
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Now, there are no absolute reports to detect interstellar glycine. to detect interstellar glycine. How is the glycine generated ?? What is the precursor of glycine in interstellar cloud ?? Do the precursor exist in interstellar cloud ??
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Strecker Reaction (Strecker (1850)) One of the famous reaction that produce amino acid in the laboratory frame. NH 3 + H 2 CO → CH 2 NH + H 2 O CH 2 NH + HCN → NH 2 CH 2 CN NH 2 CH 2 CN + H 2 O → NH 2 CH 2 CONH 2 NH 2 CH 2 CONH 2 + H 2 O → NH 2 CH 2 COOH + NH 3 ammonia formaldehyde methylenimine hydrogen cyanide aminoacetonitrile (AAN) Glycine ( Ugliengo et al. 2011 )
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AANNC 1.4760 Å 1.4760 Å CC’ 1.4611 Å 1.4611 Å C’N’ 1.1594 Å 1.1594 Å CH 1.0940 Å 1.0940 Å NH 1.0138 Å 1.0138 Å NCC’114.54° HCH102.4° HNC109.6° HNH107.3° CC’N’180.0° Pickett (1973) Hydrogen Carbon Nitrogen N N’ C C’
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MacDonald & Tyler 1972 Measured AAN spectra in microwave region. a-type: 3 lines b-type: 2 lines a-type: 3 lines b-type: 2 linesPickett1973 Measured AAN and its deuterated isotopologues (NHD-, ND 2 -) spectra in microwave region. (NHD-, ND 2 -) spectra in microwave region. Decided electric dipole moment. μ a =2.577(7)D, μ b =0.5754(10)D μ a =2.577(7)D, μ b =0.5754(10)D Brown et al. 1977 Determined hyper fine coupling constant of Nitrogen nuclei. of Nitrogen nuclei. χ aa = -2.77(0.04), χ bb = 1.20(0.09) : amino nitrogen (MHz) χ aa = -3.48(0.03), χ bb = 1.50(0.06) : nitrile nitrogen (MHz) Bogey et al. 1990 Measured AAN spectra in millimeter wave region. J’ ≤ 40 a-type: 110 lines, b-type: 5 lines. J’ ≤ 40 a-type: 110 lines, b-type: 5 lines. Determined AAN’s molecule constant.
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Parameter (MHz)Bogey et al. A30246.755(18) B 4761.06169(44) C 4310.75076(41) D J ×10 3 3.06545(48) D JK -0.055293(10) DKDK 1.0483(20) d 1 ×10 3 -0.67160(16) d 2 ×10 3 -0.03096(13) H J ×10 9 9.47(18) H JK ×10 6 -3.067(14) H KJ ×10 6 6.85(13) H K ×10 3 0.034479(90) h 2 ×10 9 -0.962(93) h 3 ×10 9 2.623(59) L JK ×10 9 -3.58(22) L KJ ×10 12 8.45(98) L K ×10 6 17.08(94) S K ×10 9 52.5(33)
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Parameter (MHz)Belloche et al. A30246.4561(71) B 4761.06102(84) C 4310.75123(76) D J ×10 3 3.06853(68) D JK -0.0552986(69) DKDK 0.67662(99) d 1 ×10 3 -0.67160(40) d 2 ×10 3 -0.028893(106) H J ×10 9 9.593(276) H JK ×10 6 -0.1201(72) H KJ ×10 6 -2.6861(268) H K ×10 3 a 0.030 a h 1 ×10 9 2.989(225) a : fixed These constants are compiled by CDMS (The Cologne Database for Molecular Spectroscopy) catalog. by CDMS (The Cologne Database for Molecular Spectroscopy) catalog. Previously(Bogey et al.) D K = 1.0483(20)
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CDMS Belloche et al. (2008) succeeded to detect AAN’s millimeter wave spectra towards Sgr B2(N)!! AAN’s millimeter wave spectra towards Sgr B2(N)!! Detected region 80~260GHz Detected line a-type transition of 51 lines GHz
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According to the CDMS catalog, AAN predictions have had large errors AAN predictions have had large errors in sub-millimeter region. in sub-millimeter region. b-type transitions have not been measured well. H K,h 1 ~h 3, and higher constants have not determined well. In this study, we measured pure rotational spectra from millimeter to sub-millimeter region. from millimeter to sub-millimeter region. Improve AAN molecule constant to measure mostly b-type and higher K a ’ transition. to measure mostly b-type and higher K a ’ transition. Find other miss-assignments.
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Spectrometer Frequency-modulated sub-millimeter wave spectrometer Frequency-modulated sub-millimeter wave spectrometer Measured region Measured region 122 ~ 188 GHz, 372 ~ 537 GHz, 621 ~ 661GHz 122 ~ 188 GHz, 372 ~ 537 GHz, 621 ~ 661GHz The sample gas was about 8×10 -3 Pa. Sample Gas (AAN) Glass Cell Transmitter InSb Detector
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J’≤74, K a ’ ≤15 a-type transitions of 107 lines were measured. J’≤74, K a ’ ≤15 a-type transitions of 107 lines were measured.
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b-type transitions of K a ’ -K a ” =2-1 were not found near the predicted frequencies in 122~188 GHz. Except all of K a ’ ≥ 2, b-type transitions. Only K a ’ -K a ” =1-0, 0-1 transitions include our fit. After that, we measured ・・・ 1.K a ’ -K a ” =1-0, 0-1 transitions in 122~188GHz. 2.K a ’ ≥ 2 transitions in 122~188GHz. 3.and Extend higher frequency region.
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A; 26 10,16 -26 9,17, 26 10,17 -26 9,18 B; 32 10,22 -32 9,23, 32 10,23 -26 9,24 C; 27 10,17 -27 9,18, 27 10,18 -27 9,19 D; 31 10,21 -31 9,22, 31 10,22 -31 9,23 E; 28 10,18 -28 9,19, 28 10,19 -28 9,20 F; 30 10,20 -30 9,21, 30 10,21 -30 9,22, 29 10,19 -26 9,20, 26 10,20 -26 9,21 29 10,19 -26 9,20, 26 10,20 -26 9,21 J’ Ka’Kc’ -J’’ Ka’’Kc’’ Head of b-type, Q-branch
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J’≤57, K a ’ ≤13 b-type transitions of 176 lines were measured. J’≤57, K a ’ ≤13 b-type transitions of 176 lines were measured.
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Parameter (MHz)Present Study Belloche et al.Bogey et al. A30246.48715(90)30246.4561(71)30246.755(18) B 4761.061966(146) 4761.06102(84) 4761.06169(44) C 4310.748772(150) 4310.75123(76) 4310.75076(41) D J ×10 3 3.066693(136) 3.06853(68) 3.06545(48) D JK ×10 2 -5.529480(85) -5.52986(69) -5.5293(10) DKDK 0.7140098(97) 0.67662(99) 1.0483(20) d 1 ×10 3 -0.6731843(229) -0.67160(40) -0.67160(16) d 2 ×10 3 -0.0299408(66) -0.028893(106) -0.03096(13) H J ×10 9 9.451(39) 9.593(276) 9.47(18) H JK ×10 6 -0.123358(172) -0.1201(72) -3.067(14) H KJ ×10 6 -2.68354(312) -2.6861(268) 6.85(13) H K ×10 3 0.052091(36) 0.030 0.034479(90) h 1 ×10 9 3.7152(43) 2.989(225) - h 2 ×10 9 0.45735(202) - -0.962(93) h 3 ×10 9 0.05303(98) - 2.623(59) L J ×10 12 -0.0217(34) - - L JK ×10 9 - - -3.58(22) L KJ ×10 12 - - 8.45(98) L K ×10 6 - - 17.08(94) S K ×10 9 - - 52.5(33)
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Present Study Belloche et al. Bogey et al. 0.9020.51 RMS39.7kHz27.2kHz
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Pure rotational spectra of AAN from millimeter to sub- millimeter wave region were measured. J’≤74, K a ’ ≤15 a-type transition of 107 lines and J’≤57, K a ’ ≤13 b-type transition of 176 lines were measured, and analyzed these lines and previous measured lines with Watson’s S-reduced Hamiltonian. Owing to measurements of high K a of b-type transition, higher order centrifugal constants were determined well. These data allow reliable predictions to do astronomical observation about 1THz.
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We thank NAOJ (National Astronomical Observatory of Japan) for lending us a synthesizer. of Japan) for lending us a synthesizer.
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Glass Cell Oscilloscope Filter PSD Modulator PC Frequency Synthesizer Rb clock GPS ×n Pirani gauge Diffusion pump Detector Amp Gas Multiplier
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