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1. CO 9-8 CO 13-12 CO 11-10 CO 12-11

   StarFormation and Band 11

   J. Cernicharo CAB. INTA-CSIC Spain CO 10-9
2. ThankstoEdBergin, Asuncion Fuente, B. Lefloch, Javier R. Goicoechea and M. Extaluzeforsomeviewgraphs and suggestions
3. Dust and Molecules Study of clustering in intermediate and highmassstars Dustpropertiesderivedfromthe 180-300 umfrequencycoverage of band 11 Study of theinnermostregions of collapsethroughhighexcitationlines of CO, HCN, HNC, SiO, CS, HF, OH+, CH3CN, … : Physicalconditions and chemistry Herschel data is a goodtemplatetoanalyzethepotential of band 11 for ALMA. Magneticfieldmeasurementsusingparamagnetichydrides. Only a fewhours of goodatmosphericconditions => short Integrations, stronglines, avoidlargemosaics. Zerospacing data is crucial fordust and molecules. Primary error beam and side lobes willlimittheimagequalitybut no waytoavoidthat in galacticsciencewith band 11
4. OH+ and polarizationmeasurementsin bands 10 & 11 LINE NuJu Fu NlJlFl FREQ(MHz) Error EuppAul ----- ----- ----- ----- ----- ----- ----- -------------- ----- ------- --------- 1 1.0 .0 .5 .0 1.0 .5 909045.20000 1.000 43.6 5.227E-03 2 1.0 .0 .5 .0 1.0 1.5 909158.80000 1.000 43.6 1.049E-02 3 1.0 2.0 2.5 .0 1.0 1.5 971803.80000 1.500 46.6 1.823E-02 4 1.0 2.0 1.5 .0 1.0 .5 971805.30000 1.500 46.6 1.519E-02 5 1.0 2.0 1.5 .0 1.0 1.5 971919.20000 1.000 46.6 3.044E-03 6 1.0 1.0 .5 .0 1.0 .5 1032997.92100 .849 49.6 1.410E-02 7 1.0 1.0 1.5 .0 1.0 .5 1033004.40000 1.000 49.6 3.527E-03 8 1.0 1.0 .5 .0 1.0 1.5 1033111.82400 .852 49.6 7.031E-03 9 1.0 1.0 1.5 .0 1.0 1.5 1033118.60000 1.000 49.6 1.760E-02 OH+ ,CH, NH, NH2 are paramagnericmolecules. Possiblemeasurements of themagneticfieldthoughZeemaneffect in theregionswherethesemolecule are formed. Differentregionsthan CN, SO, CCS,… Sameappliesto H2O+ withseverallines in band 11. Magneticmeasurements in theenvelopes of dense cores ??
5. Band 11
6. ProtostellarOutflows and Shocks L1157-mm B1 Bachilleret al. (2001), Looneyet al. (2007), Neufeldet al. (2009) Spitzer 8 μm: grey CO: contours Whichmolecularcomplexitycanbeachieved in protostellarshocks ? How doesit relate to the shockphysical conditions (B, n, T) ? Gueth et al. (1996,98) L1157-mm B1 B2 A comprehensivestudy of L1157-B1 with Herschel and the IRAM 30m as part of the Herschel/CHESS KP (PI : C. Ceccarelli) Distance: 250 pc Driven source: Class 0 protostar (L1157-mm),L= 4-11 Lo Most chemically rich outflow known so far Precessing molecular outflow associated with several bow shocks seen in CO and in H2. Ideal laboratory to observe the effects of shocks on dust and gas chemistry Benchmark for shock models (Gusdorf et al. 1998) New Trends in Radioastronomy in the ALMA Era
7. High-Excitation Gas in L1157-B1 Submm/FIR spectrumdominated by H2O, high-J CO, OH and OI High-J CO line emission (Eup= 580 – 1400K) PACS Benedettini et al. (2012) High-excitation component : CO, OI, OH  Size : 7’’ , upstream of the apex Gasat LTE with Trot= 210K Comparisonwithshockmodels for OH, OI + Spitzer  dissociative J-type shock, whichcould trace the jet impact on outflowcavity Flower & Pineau des Forets (2010) New Trends in Radioastronomy in the ALMA Era
8. Jet-DrivenBowshock Signatures Lefloch et al. (2012) CO g1 : J-type shock (210K) g2 :B1 cavitywalls (70K) g3 :B2 cavitywalls (25K) The CO emissionis the sum of the contributions of shockedgas components g1, g2, g3 modelled as exp(-|v/v0|) - different range of Jup : excitation conditions - giisindependent of Jup : isothermal - differentvelocity ranges but all peakatlow-vel. New Trends in Radioastronomy in the ALMA Era
9. Early B star outflows g ~ 3 to 4 T Tauri star outflows g = 6 to 10 dM(v)/dv g ~ 0.5 to 2.5 g ~ 2.5 to 4 vbreak(CO) v Shock Structure and Outflows Mass-velocity relation in outflows : initiallystudied in CO J=1-0, 2-1 lines In the mm : Equallywell fit by In the submm : Better fit dM(v)/dv αexp(-v/v0) CHESS Meeting 07th-09th November 2012
10. UnresolvedProblems in starformation Clustering 50 % of alllow-massstars are binaries Starswith M* > 5 Msunform in clusters Most of thelow-massstarshavevery likelybeenformed in clusters Accretionmodelscannotexplaintheformation of starswith M >10 Msun Radiationpressurewould stop theaccretionbeforereachingthe final mass (tKH<tacc). New accretionmodels (McKee & Tan 2002)Theturbulentvelocityprovidesforthehighaccretionraterequiredfortheformation of a massivestar. Coalescencemodels (Stahler 2000)Themassivestarisformedbycollisions of stars (protostars) of low and intermediatemassstars.
11. Intermediatemass (IM) stars are starswithmassesbetween 2 and 10 Msun. i) Theunderstanding of theirformationprocess of IM starsisintererestingbyitself. In fact, the IM starsdominatethe UV field in ourGalaxy (Wofire et al. 2002). ii) Theyconstitute a link betweenlow-mass and high-massstarformation. They share properties (clustering) withhighmassstarsbut are locatedclosertotheSun (D<2 Kpc).
12. Palau, Fuente et al., 2012, ApJ
13. Ma et al., 2012, ApJ
14. ALMA allbands !! Band 11 = tobettercharacterizethe SED of theobservedsources butpoorerimagequality and dynamics than in lowfrequencybands of ALMA Hot cores/corinos at scales of < 500 AU
15. HIGH MASS STAR FORMATIONandCHEMISTRY
16. Hydrides
17. Study of CO in and around massive objects such as SgrB2=> Template for the nuclei of AGNs Study of hydrides, chemistry, clumpiness Study of Ultracompact HII regions highly obscured by dusty envelopes Drawbacks: Too broad lines for magnetic field measurements Mosaicing will be always required for lines and continuum. Long observing times.
18. TheGalactic Center Sgr A*
19. Goicoechea et al., 2013, ApJ, In press
20. Band 11 : Searchforclumpystructures In high-J lines of CO. Testingthedifferent heatingmechanisms.
21. ORION as seen by HEXOS
22. Ori KL Sgr B2 N M Ori-S Ori- Bar
23. H2O H2O H2O CO J=16-15 CO J=14-13 CO J=15-14 H2O H2O CO J=13-12 CO J=11-10 CO J=10-9 CO J=9-8 CO J=8-7 CO J=7-6 CO J=6-5 CO J=5-4 Ori KL Sgr B2 N M Ori-S Ori- Bar
24. Wang et al. 2011 Complexity Overlapping emission lines Multiple line of sight components (outflow, warm and hot dense cores) Band 11 studies of the thermal structure of Orion
25. J=13-12 J=6-5 J=12-11 J=14-13 CH3CN in Orion. 30m data. Bell et al., 2013
26. AllMoleculesdetected in Orion and SgrB2 PoorerspectrumtowardsSgrA* Dedicatedstudies of all CO/13CO/C18O lines In band 11. Study of the line profiles, collapsetracers, thermalstructure of theclumps (CO, CH3OH, CH3CN, and manyotherspecies) Chemistry
27. 30 Trot = 162 K 29 28 log N/g Trot = 519 K 27 26 0 500 1000 El (K) H3O+ - Sgr B2 N
28. Collisions Radiative Decay metastable J=K inversion transitions H3O+
29. Wilson et al. 2006; Hüttemeister et al. 1995 General interpretation is the presence of a hot shocked layer of gas in front of the dense continuum source NH3 Absorption toward Sgr B2
30. Scutum, Sgr, Orion Spiral Arms 3-4 kpc arms gas in x2 orbits in galactic potential Sgr B2 Envelope High Energy H3O+ Towards the Galactic Center Line/Continuum (6,6) Line/Continuum (9,9) 1.0 0.8 NH3 Line/Continuum 0.6 0.4 -100 0 100 VLSR (km s-1)
31. Formation Pumping H2O+ + H2 → H3O+ + H + 21710 K If we assume a fraction enthalpy change goes into rotation then we can match observations need high ionization rate > 10-16 s-1 to maintain population -- has to form it and leave it present to absorb radiation before it can be destroyed. -- Can derive the formation/ionization rate!
32. Model: require high ionization rate > 10-16 s-1 to maintain population 30 Trot = 31 K Models by J. Black 28 (9,9)+ 26 Trot = 600 K ln[Nu/g] (cm-2) 24 (9,9)- 22 20 0 1000 2000 3000 4000 Eu/k (K) Lis et al., in prep.
33. Band 11: Clumpiness of CO, OH+, NH, NH2, HCl,…. Analysis of thechemicalpumpingonthe emission of high-J lines of CO. Spatial distributionis a KEY parameterto undestandif shocks, photonpumping, inelasticcollisionsor reactive collisions are dominatingtheexcitation of CO