1. A Confusion Limited Spectral Survey of Orion KL (80-280 GHz) And a 2D Spectral Line Survey at 1mm José Cernicharo (CAB. INTA-CSIC) Nuria Marcelino (NRAO), Belén Tercero, Gisela B. Esplugués, Tom Bell (CAB, Spain) Aina Palau (ICE, Spain) CO (2-1)

2.  The closest (brightest) massive star forming region, contains several compact objects  Prototypical source: observed extensively at mm and submm wavelengths  Exhibits an intense and prolific spectrum  Many spectral line surveys performed in the last 20 years (ground and space) covering most of the 70 to 2000 GHz domain.  Very rich and complex chemistry (warm gas-phase, shocks, grain mantle evaporation/desorption, etc.) Line Surveys in Orion-KL

3. Cloud components of Orion-KL  Extended Ridge: gas-phase ion-molecule chemistry; C-rich molecules (CS, CN, CCH), lack of O-rich species  Compact Ridge: shocked gas, release of oxygen from grains; abundant in complex organic molecules (CH 3 OH, HCOOCH 3, CH 3 OCH 3, etc.)  Hot Core: warm gas-phase with N-rich and H-saturated species from grains; NH 3, HDO, CH 3 CN, CH 3 CH 2 CN, etc.  Plateau: outflows; high velocity wings of CO and HCO + ; SiO, SO, SO 2, etc.; and maser emission (H 2 O, OH, SiO)

4. 13 CO (2-1) BIMA Liu et al. (2002) OVRO Blake et al. (1996)

5.  Freq. range: 80 – 280 GHz multiple transitions from the same species  Spectral resolution: ~1 MHz (3–1 km/s)  HPBW = 29 – 9’’  Line confusion limited survey deep insight into the chemistry, and detection of new molecules (isotopologs and vibrationally excited states) IRAM 30m Line Surveys: IRc2 position (Tercero et al. 2010,2011)

6. Ground Based observations of high Mass star forming regions

8. LINE CONFUSION LIMIT REACHED. WHAT TO DO ? ALMA WILL BE 8 times more sensitive than the 30-m radio telescope 33

9.  15000 lines detected (above confusion limit), of which 10000 have been assigned to 44 molecules and their isotopologues  New detections of multiple isotopic substitutions ( 18 O, D) of HCOOCH 3 and CH 3 CH 2 CN, for which new laboratory measurements were needed (Collaboration with Lille Spectroscopy Group).  5000 lines remain unidentified above the confusion limit (0.05 K at 3mm, 0.1 K at 2mm and 1mm) IRAM 30m Line Surveys: IRc2 position (Tercero et al. 2010,2011)

11. From Tercero et al., 2010, A&A, 517, A96 & 2011, A&A, 528, A26

12. Using MADEX: upper limits to the column density of hundreds of potentially interesting species From Tercero et al., 2011, A&A, 528, A26

13. Ethyl Cyanide (The Contaminator), CH 3 CH 2 CN

14. Ethyl Cyanide, CH 3 CH 2 CN (ground state)

15. Collaboration with L. Margules, I. Kleiner et al. 

16. Sym.NoApproximateFreq.Infrared Speciestype of modeValue a'1CH3 d-str30013001 VSVS a'2CH2 s-str29552955 VSVS a'3CH3 s-str29002900 SS a'4CN str22542254 VSVS a'5CH3 d-deform14651465 SS a'6CH2 scis14331433 SS a'7CH3 s-deform13871387 MM a'8CH2 wag13191319 MM a'9C-CN str10771077 SS a'10CC str10051005 MM a'11CH3 rock836836 WW a'12CCC deform545545 MM a'13CCN bend226226 MM a14CH3 d-str30013001 VSVS a15CH2 a-str28492849 SS a16CH3 d-deform14651465 SS a17CH2 twist12561256 VWVW a18CH3 rock1022 a19CH2 rock786786 MM a20CCN bend378378 MM a21Torsion222 Possible vibrational levels of CH 3 CH 2 CN in Orion: 21, 20, 19, 11, 12, 13 21 + 20, 21 + 19, 21, 12 + 13, …… For a vibrational temperature of 300 K all these levels will have a contribution 10 times larger than that of the isotopes 13 C !!! Collaboration with J.L. Alonso (Valladolid, Spain) and J. Pearson et al. (JPL) many of these levels have been detected (in progress for all levels below 1000 cm -1 ) Strong perturbations, complex Hamiltonians.

18. E vib =800 K What is the role of vibrationally excited molecules in chemistry ? Slow reactions involving ground state species could become very fast using the vibrational energy reservoir to overpass possible activation barriers. See Agúndez et al (2010, ApJ, 713, 662) for C + and H 2 (v=1)

19. In high mass star forming regions such as Orion KL the contribution to the spectral density from diatomic and triatomic molecules is through their isotopologues: SiO, 29 SiO, 30 SiO, Si 18 O, Si 17 O CS, 13 CS, C 34 S, C 33 S HCO +, DCO +, H 13 CO +, HC 18 O +, HC 17 O + HCN, DCN, H 13 CN, HC 15 N,…. Lines from the vibrationally excited states of some of them are detected but are weak (lowest vibrational energies  700-1000 cm -1 ). However, for heavy species the main contribution to the confusion is through their vibrationally excited states. For T vib =300 K all molecules having vibrationally excited states around 200 cm-1 will have N ground / N vib  3 while 12 C/ 13 C  45

20.  2x2’ maps (fully sampled) centred on IRc2  Freq. range: 200 – 282 GHz  HERA (3x3 pixels, 1 GHz) + EMIR (4 GHz)  Spectral resolution: 2 MHz (~2.6 km/s)  HPBW = 12 – 9’’ Orion-KL source components can be resolved  Spatial Sampling 4”  Confusion limited in 30”x30”  Observations completed, now in the reduction process… IRAM 30m Line Surveys: 2-D line survey (Marcelino et al., in prep.)

21. 2-D Line Survey CH 3 CN 13 CO SO C 18 O OCS H 2 CO CH 3 OH HC 3 N H 2 CO DCN SiO SH 2 SO 2 Orion-IRc2 HCOOCH 3

22. CH 3 CN 13 CO SO C 18 O OCS H 2 CO CH 3 OH HC 3 N H 2 CO DCN SiO SH 2 Compact Ridge 2-D Line Survey HCOOCH 3 SO 2 SH 2

23. CH 3 CN 13 CO SO C 18 O OCS H 2 CO CH 3 OH HC 3 N H 2 CO DCN SiO SH 2 Extended Ridge 2-D Line Survey SO 2 SH 2 HCOOCH 3

24. CH 3 CN 13 CO SO C 18 O OCS H 2 CO CH 3 OH HC 3 N H 2 CO DCN SiO SH 2 (20’’, 50’’) 2-D Line Survey SO 2 SH 2 HCOOCH 3

25. H 2 CO (3 03 -2 02 )HC 3 N (24-23)CH 3 OH (4 22 -3 12 E) 2-D Line Survey

26.  Herschel/HIFI Orion KL line survey from the Key Project “HIFI observations of EXtra-Ordinary Sources” (Bergin et al. 2010) — Freqs: 480 – 1250 GHz; 1410 – 1910 GHz — Spectral resolution: 0.5 MHz (0.3–0.1 km/s) — HPBW = 45 – 18’’ ➜ S-C chains and Si (B. Tercero –CAB, Madrid) ➜ SO and SO 2 (G.B. Esplugués –CAB, Madrid) ➜ CH 3 CN (T. Bell –CAB, Madrid) ➜ CH 2 CHCN (A. López-CAB, Madrid) ➜ CH 3 CH 2 CN (Adam Lay, GEM, U. Valladolid) ➜ Deuterated HCN, HNC, HCO + (N. Marcelino) HEXOS collaboration

27. 2-D Line Survey

30. LVG model

31. Summary Large frequency coverage surveys provide multiple transitions of the same species (same calibration, better N and T rot estimations) A three layer stratification model for CR, P and HC, has been used to simulate the source and obtain column densities. Only possible thanks to high excitation HIFI transitions ! Spatial distribution of each species (both small and large scale structures) is essential to understand their chemical formation pathways ALMA will provide wide frequency range together with high spatial resolution to identify the main emitting sources A lot of laboratory work is still needed to interpret the spectrum of Orion KL. Each high mass star forming region observed with ALMA will looks similar to Orion....