ger S. P. Müller, C. P. Endres, J. Stutzki, S. Schlemme I. Physikalisches Institut, Universität zu Köln, 50937 Cologne, Germany The CDMS View on Molecular Data Needs of Herschel, SOFIA, and ALMA ernational Conference on Atomic and Molecular Data and Their Applic A 2012, Sep. 30 – Oct. 4, 2012, NIST, Gaithersburg, MD, USA
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The CDMS View on Molecular Data Needs of Herschel , SOFIA, and ALMA
Holger S. P. Müller , C. P. Endres, J. Stutzki, S. Schlemmer. The CDMS View on Molecular Data Needs of Herschel , SOFIA, and ALMA. I. Physikalisches Institut, Universität zu Köln, 50937 Cologne, Germany. 8th International Conference on Atomic and Molecular Data and Their Applications, - PowerPoint PPT Presentation
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Holger S. P. Müller, C. P. Endres, J. Stutzki, S. Schlemmer
I. Physikalisches Institut, Universität zu Köln, 50937 Cologne, Germany
The CDMS View on Molecular Data Needsof Herschel, SOFIA, and ALMA
8th International Conference on Atomic and Molecular Data and Their Applications,ICAMDATA 2012, Sep. 30 – Oct. 4, 2012, NIST, Gaithersburg, MD, USA
Acknowledgments
Bundesministerium für Bildung und Forschung (BMBF) (German Department for Education and Research)
via Herschel/HIFI ICCand German ALMA regional Center
unfortunately not a stable support
Detection of 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 !
Also for extragalactic CO observations !
CDMS Main Page
release of test version of database environment will be announced heretwo posters (27, 28) on VAMDC by M. L. Dubernet on Wednesday
CDMS Catalog: Basic Facts
line lists of rotational spectra for molecules of interest in space
using tested Hamiltonian models based on critically evaluated experimental data
657 different species; 279 detected in ISM or CSE (Sep. 2012)
separate entries for isotopologues and vibrational states
~2000 accesses each month
included in many advanced astronomy tools, e.g. for Herschel
~5 new entries each month
Why Evaluate Experimental Data or Hamiltonian?
Experimental uncertainties are sometimes – not reported – too optimistic or too pessimistic – not related to reported residuals
The Hamiltonian may be – incomplete – too extensive – incompletely diagonalized
Treatment of blended lines may be incorrect
Example NaCN: H. S. P. Müller et al., J. Mol. Spectrosc. 272 (2012) 23
Entries
Species tag.: mw5#Name/Formula DocumentationMHz Entry cm–1
Example of a Current Documentation
How can we raise the visibility of spectroscopic work ?
CO entryExplanations with link to further detailsFrequency (MHz)Uncertainty (MHz)Elower (cm–1)gupSpecies tagQuantum numbersIntensity (nm2MHz)
Considerations for Herschel, SOFIA, APEX, etc.
after Wilhelm/William & Caroline Herschel− Heterodyne Instrument for the Far-Infrared high-resolution; 0.48−1.25, 1,44−1.91 THz− SPIRE & PACS; med.-res.; 0.6−5.2 THz
Stratospheric Observatory for Far-Infrared Applications− high-res.: German REceiver At Terahertz Frequencies ~1.3, 1.8, 2.5 THz; more with up-GREAT
Atacama Pathfinder Experiment− high.-res.; several atmospheric windows < 1.5 THz
Astron. Astrophys. 454 (2006) letters
Astron. Astrophys. 542 (2012) letters
Astron. Astrophys. 518, 521 (2010) letters
Goals and Findings of Herschel
major goals:− atomic fine structure lines (C+, N+, O)− O2, low-lying lines of cold H2O− high-lying lines of CO, HCN, HNC, HCO+, etc.− (fundamental) transitions of light hydrides (AHn
(+))− complex molecules, e.g. CH3OH, CH3OCH3
important findings:− there is O2 in the ISM, albeit very little: P. F. Goldsmith et al., ApJ 737 (2011) 96; R. Liseau et al., A&A 541 (2012) A73− abundance of H2O varies greatly− extensive observations of light hydrides, e.g. CH+, CH, NH3, NH2, NH, OH, H3O+, HF− most complex molecules hard to see− very abundant SiC2 around CW Leo (IRC +10216): H. S. P. Müller et al., J. Mol. Spectrosc. 271 (2012) 50
Detection of H2O+ with HIFI/Herschel
V. Ossenkopf et al., Astron. Astrophys. 518 (2010) L111
DR 21NGC 6334
Sgr B2(M)
Other Detections of Light Hydrides
OH+, APEX: F. Wyrowski et al., Astron. Astrophys. 518 (2012) A26; (+ Herschel)
ND, HIFI/Herschel: A. Bacmann et al., A&A 521 (2010) L42
OD, GREAT/SOFIA: B. Parise et al., A&A 542 (2012) L5
SH+, APEX: K. M. Menten et al., A&A 525 (2010) A77; (+HIFI/Herschel)
SH, GREAT/SOFIA: D. A. Neufeld et al., A&A 542 (2012) L6
H2Cl+, HIFI/Herschel: D. C. Lis et al., A&A 521 (2010) L9
HCl+, HIFI/Herschel: M. De Luca et al., ApJ 751 (2012) L37
Data Needs of Herschel etc.
light hydrides: CH2+, H2S+
detected or known hydrides, complex molecules: ALMA related: highly rot. or vib. excited lines minor isotopic species
some features remain unassigned, e.g.:
A submillimeter Diffuse Interstellar Band
spiral arm clouds
spiral arm clouds
spiral arm clouds
spiral arm clouds
Sgr B2(M) Sgr B2(N)
Considerations for ALMA (Atacama Large Millimeter Array)
Interferometry spatial resolutionuseful for the study of
(galaxies)
star-forming regions (complex molecules)
circumstellar envelopes of late-type stars (composition, dust formation)
(circumstellar envelopes of young stars)
Chilean Andes, 5100 m
Star-forming Regions
dense molecular clouds (> 1000 H2/cm3)
prestellar: cold (~10 K), more unsaturated molecules
very yound stars: warm (~50 K) to hot (> 200 K) more saturated molecules rich in complex molecules
Difficulties to Detect Complex Molecules
larger molecules are usually rarer,
have more rotational and vibrational levels, maybe several conformers
larger molecules are frequently less volatile
less favorable partition function
the weak lines may be blended with stronger lines
interferometry may be required for detection or confirmation
previously in G10.47+0.03: Wyrowski et al; A&A 381 (1999) 882
CH312/13CN, v8 = 1 in Sgr B2(N)
Circumstellar Shells of Late-Type Stars
phases between H burning and white dwarf/(super) nova
(most) important contributors to interstellar dust
different flavors: C-rich, O-rich, [C] ≈ [O]
C-rich Late-Type Stars
examples: CW Leo (IRC +10216), CRL 618, CRL 2688
findings: CO, C-chain molecules, Si molecules, metal halides, cyanides, isocyanides
recent findings: anions, e.g. C6H−, M. C. McCarthy et al., ApJ 652 (2006) L141, C5N−, J. Cernicharo et al., ApJ 688 (2008) L83; FeCN, L. N. Zack et al., ApJ 733 (2011) L36
data needs: metal halides, (iso-) cyanides, etc., some anions
O-rich Late-Type Stars
examples: VY CMa, IK Tau
findings: CO, HCN, various oxides and some sulfides