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Multi-wavelength Astronomy and the Virtual Observatory, Workshop @ ESAC, Spain, Dec. 1 − 3, 2008 Holger S. P. Müller, J. Stutzki, S. Schlemmer I. Physikalisches Institut Universität zu Köln 50937 Cologne, Germany The CDMS, a database for molecular line identification especially for Herschel, SOFIA, and ALMA
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CF + toward the Orion Bar CF + J = 3 – 2 APEX CF + J = 2 – 1 IRAM 30m CF + J = 1 – 0 IRAM 30m D. A. Neufeld et al., Astron. Astrophys. 454 (2006) L37 Rest frequencies required for line identification !
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CDMS Main Page Please bookmark as http://www.astro.uni-koeln.de/cdms/ Short-cut to CDMS main page: www.cdms.de
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CDMS catalog: basic facts line lists of rotational spectra for molecules of interest in space Hamiltonian model based on experimental data 486 different species; 228 detected in ISM or CSE separate entries for isotopologues and vibrational states ~ 1000 users each month included in many advanced astronomy tools, e.g. for Herschel ~ 5 new or updated entries each month
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General
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general II
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general III
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Entries Species tag.: mw5# Name/FormulaMHz Entry cm –1 Documentation
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Entries are Based on Laboratory Data, e. g., CO Spectroscopic Parameters / MHz Important: appropriate uncertainties
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CO entry Explanations with link to further detailsFrequency (MHz)Uncertainty (MHz)E lower (cm –1 )g up Species tagQuantum numbersIntensity (nm 2 MHz)
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CO documentation
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Graphic Output for SO 2 at 150 K
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what’s new
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Reasons for an open sytem: newly detected molecules (2006–2008) C 4 H –, C 6 H –, C 8 H –, C 3 N –, C 5 N – HCP, CCP, PO, PH 3 (?) H 2 NCH 2 CN, NCCHO, H 2 C=C=CHCN CF +, O 2 CH 3 C(O)NH 2, c-H 2 C 3 O, H 2 C=CHCH 3, CH 3 C 6 H
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Complex organic molecules: aminoacetonitrile H 2 NCH 2 CN (a likely precursor of glycine, H 2 NCH 2 COOH) A. Belloche et al., Astron. Astrophys. 482 (2008) 179
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C 2 H 3 CN, v = 0, + 13 C, + 15 N H. S. P. Müller et al., J. Mol. Spectrosc. 251 (2008) 319 Complex organic molecules: vinyl cyanide
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Reasons for an open system: missing or insufficient data Note: accurate rest frequencies etc are needed not only for desired species, but also for possibly interfering species somewhat problematic for Herschel & SOFIA (light hydride species, small molecules, methanol...) severe problem for ALMA ! (many simple or complex molecules, minor isotopologues, excited vibrational states)
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Detection of 13 CH + J = 1 − 0 toward G10.6−0.4 with the CSO E. Falgarone et al., ApJ 634 (2005) L149 CH 3 OH 13 CH + no accurate 13 CH + lab data no kinematic information
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HNCO in Sgr B2(N) v = 0, v 5 = 1 (831 K), v 6 = 1 (944 K), v 4 = 1 (1117 K) previously in G10.47+0.03: Wyrowski et al; A&A 381 (1999) 882
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Reasons for an open system: lack of manpower one person for creating entries etc. no person for programing
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Problems related to multiple sources which of two or more entries for one species is better ? the newer one ? the one with more/higher predictions/lab data ? the one with smaller uncertainties ? quantum number assignments may be ambiguous ! Hund’s case a/b... (a-) symmetric coupling of nuclear spin moments (electronic-) vibration-rotation (spin) interaction
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Quantum number format N, K a, K c, v, F 1,... F strictly, only F is a good quantum number N, K a, K c, v are often meaningful, but... K a + K c ±K for symmetric tops half-integer quantum numbers are rounded up meaning of v divers (vibrational, electronic state; isotopologue...)
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Acknowledgments DFG (Deutsche Forschungsgemeinschaft) → 2006 BMBF (Bundesministerium für Bildung und Forschung)
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