Multi-wavelength Astronomy and the Virtual Observatory, ESAC, Spain, Dec. 1 − 3, 2008 Holger S. P. Müller, J. Stutzki, S. Schlemmer I. Physikalisches Institut Universität zu Köln Cologne, Germany The CDMS, a database for molecular line identification especially for Herschel, SOFIA, and ALMA

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 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

General

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Entries Species tag.: mw5# Name/FormulaMHz Entry cm –1 Documentation

Entries are Based on Laboratory Data, e. g., CO Spectroscopic Parameters / MHz Important: appropriate uncertainties

CO entry Explanations with link to further detailsFrequency (MHz)Uncertainty (MHz)E lower (cm –1 )g up Species tagQuantum numbersIntensity (nm 2 MHz)

CO documentation

Graphic Output for SO 2 at 150 K

what’s new

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

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

 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

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)

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

HNCO in Sgr B2(N) v = 0, v 5 = 1 (831 K), v 6 = 1 (944 K), v 4 = 1 (1117 K) previously in G : Wyrowski et al; A&A 381 (1999) 882

Reasons for an open system: lack of manpower  one person for creating entries etc.  no person for programing

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

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...)

Acknowledgments  DFG (Deutsche Forschungsgemeinschaft) → 2006  BMBF (Bundesministerium für Bildung und Forschung)