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Line Surveys. Peter Schilke, MPIfR. Why line surveys?. Unbiased and complete Pioneers: roadmap “because it’s there” Inventory of lines and species Finding the unexpected New species New lines (e.g. of highly excited states) Incomplete Molecular fingerprints. Orion at 650 GHz.
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Line Surveys Peter Schilke, MPIfR Peter Schilke Submillimeter Astronomy June 15, 2005
Why line surveys? • Unbiased and complete • Pioneers: roadmap “because it’s there” • Inventory of lines and species • Finding the unexpected • New species • New lines (e.g. of highly excited states) • Incomplete • Molecular fingerprints Peter Schilke Submillimeter Astronomy June 15, 2005
Orion at 650 GHz Schilke et al. 2001 Peter Schilke Submillimeter Astronomy June 15, 2005
SiH: tentative detection Schilke et al. 2001 Peter Schilke Submillimeter Astronomy June 15, 2005
Why more line surveys? • Having dozens or hundreds of lines for each species (and isotopologues) offers very strong constraints on models of • Temperature structure • Density structure • Abundance structure • Comparison of several species • Constrain chemical models • Constrain history (chemical memory of freeze-out phase, shocks etc.) Peter Schilke Submillimeter Astronomy June 15, 2005
Where? • Star Forming Regions • High Mass (hot cores) [Orion] • High Mass Protostellar Objects • Low Mass Protostars • Protostellar Disks • ISM • Absorption lines • Stars • AGB stars [IRC+10 216] • PPN • PN • Galaxies Peter Schilke Submillimeter Astronomy June 15, 2005
How? • Single dish (submm+FIR only) • Ground based (CSO, JCMT, ASTE, APEX) • Airplane based (SOFIA) • Space based (ISO, Herschel/HIFI) • Interferometer • mm (PdB, OVRO+BIMA=CARMA, NMA) • submm (SMA, ALMA) Peter Schilke Submillimeter Astronomy June 15, 2005
Historic line surveys • Almost complete: • Orion-KL • Fairly good: • SgrB2(M) and (N), • IRC+10216 • Partial: • Various UCHIIs. Peter Schilke Submillimeter Astronomy June 15, 2005
Line surveys of Orion-KL Peter Schilke Submillimeter Astronomy June 15, 2005
Orion at 345, 650 and 850 GHz Schilke et al. 1997, 2001 Comito et al. 2005 Peter Schilke Submillimeter Astronomy June 15, 2005
NGC 6334 I Thorwirth et al. in prep Peter Schilke Submillimeter Astronomy June 15, 2005
SgrB2(M+N) at 3mm BIMA + NRAO 12m Friedel et al. 2004 Peter Schilke Submillimeter Astronomy June 15, 2005
SgrB2(M+N) at 3mm 30 m telescope Belloche, Comito, Hieret, Menten, Schilke, in prep. Peter Schilke Submillimeter Astronomy June 15, 2005
SgrB2 with ISO LPW Polehampton et al. in prep Peter Schilke Submillimeter Astronomy June 15, 2005
IRC+10216 Cernicharo et al. 2000 Peter Schilke Submillimeter Astronomy June 15, 2005
Interferometric line surveys Orion KL: spectra Blake et al. 1996 See next talk by Beuther!!! Peter Schilke Submillimeter Astronomy June 15, 2005
Orion KL: spatial structure Blake et al. 1996 Peter Schilke Submillimeter Astronomy June 15, 2005
Interferometric line surveys • Interferometric line surveys are • Very rich in information • Very cheap to get (one night of data) • A nightmare to interpret • Particularly if the UV plane isn’t fully sampled need for high fidelity imaging • Since the tools aren’t there Peter Schilke Submillimeter Astronomy June 15, 2005
W3(OH/H2O) Wyrowski et al. 1999 Peter Schilke Submillimeter Astronomy June 15, 2005
W3(OH/H2O): complex molecules Wyrowski et al. 1999 Peter Schilke Submillimeter Astronomy June 15, 2005
W3(H2O): temperature Wyrowski et al. 1999 Peter Schilke Submillimeter Astronomy June 15, 2005
W3(H2O): H2 column density Wyrowski et al. 1999 Peter Schilke Submillimeter Astronomy June 15, 2005
W3(OH) abundances Wyrowski et al. 1999 Peter Schilke Submillimeter Astronomy June 15, 2005
Why should YOU care? • With sensitive instruments and wide backends involuntary Line Surveys (at least partial ones) will become commonplace • You’ll get more than you think in more source classes than you think • Be prepared! Peter Schilke Submillimeter Astronomy June 15, 2005
G10.47: hot core Leurini et al. in prep Peter Schilke Submillimeter Astronomy June 15, 2005
IRAS 18089-1732: HMPO Leurini et al. in prep Peter Schilke Submillimeter Astronomy June 15, 2005
IRAS 16293: hot corino • Lifetime problem: secondary molecules shouldn’t be there • don’t understand gas dynamics • don’t understand chemistry Caux, Castets, Parise et al. in prep Peter Schilke Submillimeter Astronomy June 15, 2005
Galaxies: NGC 253 Martin et al. in prep see poster Peter Schilke Submillimeter Astronomy June 15, 2005
Future line surveys/surveys in progress • More source types/more sources • PPN, PN, HMPOs, Galaxies, PDRs • Wide frequency ranges: • Submm telescopes • SOFIA • Herschel/HIFI • Adding spatial dimension • Interferometric line surveys Peter Schilke Submillimeter Astronomy June 15, 2005
Herschel/HIFI line survey Peter Schilke Submillimeter Astronomy June 15, 2005
Bottlenecks I • Line identification • Line databases incomplete • Lots of interstellar weed lines missing (vibrationally excited C2H5CN etc.) • Prospects for identification of complex new molecules bleak see Poster by Müller et al. Peter Schilke Submillimeter Astronomy June 15, 2005
Bottlenecks II • Modeling tools • Few 1-d LTE models for multi-molecule modeling available • Nothing more sophisticated for multi-molecule fits • Transfer: LVG, ALI, MC • Collision rates for many molecules not available • Need to be automatized to deal with large data volumes that even today are being produced • Close interaction with theorists • Star formation processes • Chemical processes Peter Schilke Submillimeter Astronomy June 15, 2005
Rotation diagram analysis Completely academic for large line surveys, requires fitting of hundreds of lines Peter Schilke Submillimeter Astronomy June 15, 2005
LTE modeling Peter Schilke Submillimeter Astronomy June 15, 2005
CRL 618 Pardo et al. in prep Peter Schilke Submillimeter Astronomy June 15, 2005
Methanol LVG modeling Leurini et al. in prep Peter Schilke Submillimeter Astronomy June 15, 2005
Outlook • The Good: • New instruments are bringing, and will bring, lots of new data, which potentially can constrain models of star formation and early stellar evolution, and stellar evolution, and galaxy evolution, and… • The Bad: • We are lacking the tools to exploit these data. • The Ugly: • Funding agencies are very hesitant to pay for development of such tools Peter Schilke Submillimeter Astronomy June 15, 2005