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 ?

With annotated line lists:

J' Ka' Kc' J" Ka" Kc" Frequency Unc. Source

1 0 1 0 0 0 1370084.880 0.020 /Asvany et al., 20081 1 0 1 1 1 372421.385 0.010 /Amano and Hirao, 20052 0 2 1 0 1 2576759.63 0.91 /Amano, 2006; Yonezu et al., 20092 1 2 1 1 1 2363242.82 0.69 /Yonezu et al., 20092 1 1 1 1 0 3102329.15 0.56 /Amano, 2006; Yonezu et al., 20092 2 0 2 2 1 155987.185 0.037 /Saito et al., 19853 1 3 2 1 2 3453653.20 0.44 /Amano, 2006; Yonezu et al., 20093 2 1 3 2 2 646430.295 0.050 /Amano and Hirao, 2005

And Literature File

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

detection maybe better (well) below Boltzmann peak

Detection of a Complex Organic Molecule: Aminoacetonitrile

H2NCH2CN (a likely precursor of glycine, H2NCH2COOH)

A. Belloche et al., Astron. Astrophys. 482 (2008) 179

IRA

M 3

0m

PdB

I, A

TC

A

Other Recent Detections

n-propyl cyanide (C3H7CN) & ethyl formate (C2H5OCHO) A. Belloche et al., Astron. Astrophys. 499 (2009) 215

high energy conformer (~1800 K) of methyl formate (CH3OCHO) J. L. Neill et al., Astrophys. J. 755 (2012) 153

not yet glycine (H2NCH2COOH) L. E. Snyder et al., Astrophys. J. 619 (2005) 914

Data Needs Concerning Complex Molecules

organic molecules with 3 to 6 heavy atoms (many studied, many not; some already detected)

consider detections, expect surprises

also needed: data for excited states or rarer isotopologs of already detected molecules, e.g.:

HNCO in Sgr B2(N)v = 0, v5 = 1 (831 K), v6 = 1 (944 K), v4 = 1 (1117 K)

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

recent findings: PO, AlO, AlOH E.D. Tenenbaum et al., ApJ 666 (2007) L29; 694 (2009) L59; 712 (2010) L93

data needs: metal oxides, hydroxides, sulfides, etc.

On Molecules in Space: http://www.astro.uni-koeln.de/cdms/molecules

Galactic and Extragalactic lists are up-to-date

Added or updated documentations on detections

What about entries generated by other programs ?

We do accept predictions generated by other programs (e.g. BELGI) !

We do need about the same pieces of information:

Some form of intensity information – Sµ2 or A are fine

Frequencies with uncertainties and quantum numbers

Q and gI or gup values

Some form of documentation and an experimental line list

An energy file containing at least all states in the prediction