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New Astronomy Highlights from the Submm Spectroscopy Satellite Odin - Åke Hjalmarson

New Astronomy Highlights from the Submm Spectroscopy Satellite Odin - Åke Hjalmarson. 50 % Astronomy ******* 50 % Aeronomy Launched on 20 February 2001 - still in action. Some Odin Quick - Facts :.

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New Astronomy Highlights from the Submm Spectroscopy Satellite Odin - Åke Hjalmarson

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  1. New Astronomy Highlights from the Submm Spectroscopy Satellite Odin - Åke Hjalmarson 50 % Astronomy ******* 50 % Aeronomy Launched on 20 February 2001 - still in action

  2. Some Odin Quick - Facts : * 1.1 m telescope (beam sizes: 2’ / 9’ at submm /mm) * 4 x cryo-cooled, tuneable submm mixers (486-504 & 541-581 GHz) * Cryo-cooled HEMT receiver at 119 GHz dedicated to sensitive O2 searches * Broad-band AOS (BW = 1040 MHz) * 2 x Hybrid autocorrelators (BW= 100-800 MHz) ”Simultaneous observations using any combination of three receivers - incl. 119 GHz HEMT”

  3. Topics to be discussed in this Talk: • The detection of molecular oxygen (O2) and its importance • High H2O abundance in the PDR interface layer between the M42 HII region and the Orion KL molecular cloud • The Orion KL spectral scan (incl. the six H2O isotopologue lines detected, the severe blends with other emission lines in the line wings of H218O, H217O, 13CO and CO…), and the (very) tentative identifications of ND and SH- • Observations of H2O and HCO+ (1-0) in absorption, suggesting a constant H2O / HCO+ abundance ratio ≈ 5 • And - if time allows …

  4. First detection of O2 in the ISMSource:  Oph A - Larsson, Liseau, Pagani et al. (2006) • JCMT CO(3-2) map, convolved to 10’ beam • Odin H2O (110-101) map, convolved to 10’ beam (”Productive” H2O mapping & deep O2 search simultaneously) <<< Odin O2 (11-10) line (beam size: 10’ at 119 GHz) X(O2) = (3-5) x 10-8

  5. Why is O2 important ? • Predicted to be abundant by chemical modelling • If abundant: an important coolant governing the cloud evolution towards star formation ! • O2 no longer is an important coolant … • The observed low abundance requires re-thinking in modelling, with consequences for the formation of other molecules, too … • Where is all the Oxygen ??? ”Trapped as H2O ice, formed on the grain surfaces - not only formed in gas phase and then trapped”

  6. Water in Orion KL -fromoutflow(s) andthe warm HII region/cloud interface (?)(Henrik Olofsson et al. 2003)

  7. What is the origin and abundance of the strong, extended H2O emission across Orion KL? * SWAS / Melnick & Bergin (2005): ”H2O is correlated with CN(1-0) - a PDR surface tracer, and not with C18O(1-0) - a volume tracer” * ”Odin’s simultaneous 13CO(5-4) & H2O mapping also hints at an origin in the hot surface layer between the M42 HII region and the molecular cloud” (Wirström 2006) >>>>>>>>>>>>>>>>>>>>>>>

  8. Also: ”Our Orion KL 13CO(5-4) map at 40” resolution is very similar to the published CN, OI & CII maps”(deconvolution of the Odin mapping cubes - Rydbeck, Olofsson, Wirström et al.)

  9. H2O, CO, 13CO & C18O (J = 5-4) mapping New N(H2) estimate & H2O analysis >>> X(H2O) > 8 x 10-8(Eva Wirström et al. 2006; A&A)

  10. X(H2O) towards the Orion Bar ”Get N(H2) of the warm interface layer between the M42 HII region and the molecular cloud from our simultaneous mapping of H2O, CO & 13CO J=5-4 + some C18O J=5-4data, then subtract the H2 column of the cloud core…” We then may use the March 2006 Odin detection of H218O to more accurately estimate the H2O abundance in the Bar: <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< My preliminary result is: N(H2O)/N(H2) ≈ 10-6 (Goal: to use map deconvolutions)

  11. Odin’s sensitivity area (beam size) shown on a VLT (ISAAC) Orion Image

  12. Orion KL spectral scan(Henrik Olofsson et al.,Carina Persson et al., two A&A papers 2006) Total coverage: 487- 492 & 541-576 GHz, ≈ 350 spectral lines Obs. time: 50 hours / GHz Shown here: ≈ 60 signals in the band 547- 553 GHz Note the severe blends in H218O, H217O & 13CO

  13. Water emissions in Orion KL • HDO (20 2 - 111) Eu = 66 K • para-H2O ( 62 4 - 71 7) Hot Core, Eu = 868 K • ortho-H2O (110 - 101) Eu = 27 K (61 K) • H218O + BLENDS !!! • H217O + BLENDS !!! Cure the blends !!!

  14. Predict blend intensities using SO2 & 34SO2 rotation diagrams

  15. Predict blend intensities using CH3OH rotation diagrams

  16. Water lines in Orion with blends removed”Carina Persson’s best efforts as of yesterday” • Compact ridge +outflow • Hot core (Eu = 867 K) • Hot core (Eu = 430 K) • Low-velocity flow + surface + weak high velocity wing(s) • same as for H218O • High-velocity bipolar outflow + self-absorbed low velocity flow

  17. ND ??? - a new molecule in the Orion KL hot core • Search motivated by CRYRING measurements of the N2H++ e recombination reaction leading to only 36 % N2 - but instead 64 % NH, and hence • High NH abundance from gas-phase reactions, but no Odin detection of ND in IRAS 16293-2422 • The present (tentative) Odin detection of 2 weak line groups of ND in the Orion Hot Core rather indicates the importance of grain surface chemistry !!!

  18. SH- ??? - the First Interstellar Anion ”If true - this would be the first detection of a negatively charged interstellar molecular ion”

  19. Water (Odin) & HCO+(OSO; J=1-0) towards W49N(G.Olofsson, J. Black, M. Olberg, C.D. Wilson et al. et al. 2006) N(H2O) ≈ 5 x N(HCO+) in diffuse ”spiral arm” absorption clouds towards W49N, W 51 & G34.3 - 0.2

  20. Infall / Outflow / Absorption towards the G34.3-0.2 hot core (M. Olberg, G. Olofsson et al.) Very recent Odin observation: < CO (5-4) - red & blue outflow < NH3 (10-00) - hot core & absorption < H2O (10-01) - absorptions & weak hot core & red outflow

  21. What remains to be said ??? • November 2005 H2O observations of the bipolar outflow in L 1157 • May 2006 H2O observations of the disintegrating Comet 73P /Schwassmann-Wachmann 3 • Spectral scan searches for Primordial Molecules ”You may ask me …”

  22. Bipolar outflow in L1157 • Blue- and red-shifted flows in IRAM CO(2-1) map • Odin’s four map points are indicated by beam-size circles

  23. Odin’s H2O mapping of L1157(Olberg, Liseau, Ristrocelli et al. 2006) • Blue- and red- shifted high-velocity line wings • Shock enhanced H2O abundance • Narrow self-absorption of ambient cloud H2O

  24. Comet 73P/Schwassmann-Wachmann 3- Fragment B (HST on April 18) Picture spans over 3000 km at a distance of 32 Mkm On May 13 this comet was only 11 Mkm from the Earth

  25. Comet 73P-Fragment B (Odin H2O, 05 May 2006) Water production rate ≈ 4 x 1027 molecules/sec

  26. Odin - H2O Outburst in Comet 73P - Fragment B

  27. IR mosaic picture of Comet 73P on 4-6 May 2006 • Picture mosaic by by IR camera on Spitzer Space Telescope • Picture size 6° (≈ 12 full Moons) • Fragment B is left of centre / Fragment C is upper right

  28. Comet 73P - Fragment C (Odin H2O, 5 May 2006)

  29. H2O, H218O & NH3 in 12+ Comets(Biver et al. 2006 - Planetary and Space Science, in press; Biver et al. 2006 - in Icarus special issue on Deep Impact) • Cometary physics & deep frozen info from the protosolar nebula • Reference water abundance(”evaporation of water ice”)for abundances of other molecules, e.g., important for the ideas of ”Supply of H2O, etc., to Planets (the Earth) and the Origin of Life”

  30. Spectral scan searches for Primordial Molecules -”Hunting structure formation during the dark ages of the Universe”(Carina Persson, Encrenaz, Hjalmarson, Rydbeck et al. 2006)

  31. Some references: • Larsson, Liseau, Pagani et al. 2006: ”First detection of molecular oxygen in the interstellar medium”, A&A • Wirström et al. 2006: ”Odin CO and 13CO J = 5=4 mapping of Orion KL - a step towards accurate water abundances, A&A • Hjalmarson et al. 2005: ”Odin Astronomy Highlights”, Advances in Space Research 36, 1031-1047. • Biver et al. 2006: Observations of Comets with Odin, Planetary and Space Science, in press. • Biver et al. 2006: Observations of Comet Tempel 1 before and after after Deep Impact, in the Special Deep Impact Issue of Icarus.

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