Galaxies of Many Colours: Star Formation Across Cosmic Time. z=0, t= /-0.037x10 9 years (Now)

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1 Galaxies of Many Colours: Star Formation Across Cosmic Time z=0, t= /-0.037x10 9 years (Now)

2 And if you want to study the initial conditions for star formation the colour is black Dense Gas SDC335: N 2 H + J=1-0 Mopra 30 ALMA 5

3 ALMA Dust Continuum Emission NASA Hubble Orion Trapizium cluster SDC335 in fewx105 yr? Size (pc) Mass (103 Msun) SDC B0.5-B1 + 2x B Centre Three stars M>9.7Mo MM Msun MM Msun Region (Peretto et al 2013; Avison et al 2015) Can form ~750 stars down to M=0.08Mo using only ~5% of total mass

4 The Hot Dense Gas in W49: A Possible Analogue of Extragalactic Starbursts Gary Fuller Jodrell Bank Centre for Astrophysics & UK ALMA Regional Centre Node, University of Manchester Floris van der Tak (SRON), Rene Plume (Calgary) Zsofia Nagy (SRON/Toledo), Helen Roberts (Manchester)

5 Introducing W49N (Wu et al 2014) Mass 106 M, L~107 L -> L/M~10 D=11.4 kpc 30 O stars in central cluster. One star O2-3.5If*, M (Galvan-Madrid et al. 2013) CO 1-0 (Gwinn et al 1992, Alves & Homeier 2003,Wu et al 2015)) C18O 1-0

6 JCMT Spectral Legacy Survey Spectral imaging survey using HARP/ACSIS on JCMT 330 GHz to 373 GHz, 1 km/s channels Fully sampled 2 x2 field, 15 beam (0.8 pc at W49) Four targets: Photon dominated region: Orion Bar Low mass protobinary: NGC1333 IRAS4 High mass protostar: AFGL2591 Galactic starburst: W49A (Plume et al 2007)

7 W49 Data (Nagy et al 2015) HCN J=4-3

8 Survey Depth & Uniformity

9 W49: Line Richness 255 lines from 63 species 41 SO 2 lines plus SO 2 26 CH 3 OH

10 W49 Spectra

11 HCN,HNC, HCO + J=4-3 N E SW Integrated Intensity HCO + J=4-3 Infall profiles - Infall? (Roberts et al. 2011)

12 Centre East North Southwest

13 HCN Models (Roberts et al. 2011)

14 Submm-HCN Diagram: toward the submm-version of the BPT-diagram HCN(4-3)/CS(7-6) integrated intensity ratio AGN Buried-AGN LX~2E43 erg/s SB Filled: Interferometer Empty: Single Dish SB-dominated N7469 N1068 (AGN) N4418 N1097 LX~7E40 erg/s AGN-dominated N1068 (APEX) IRAS N1068 (W-knot) LX~1E43 erg/s N1068 (E-knot) Izumi et al. 2015b submitted to ApJ (updated from Izumi et al. 2013) HCN(4-3)/HCO + (4-3) integrated intensity ratio

15 PDR or XDR? (Meijerink et al 2007)

16 W49: Warm and Hot H 2 CO Line Ratio H 2 CO: 110 K HCN/HNC: 75 K H 2 CO: >300K HCN/HNC: 100K 0.8pc + (HCN/HNC/HCO Roberts et al 2011 H CO Nagy et al 2012) 2 H 2 CO: 90 K HCN/HNC: 40 K H 2 CO: 90 K HCN/HNC: 40 K

17 Origin of the Hot Gas Mechanical heating from stellar winds, bipolar outflows, UCHII region expansion: 30 O stars in central cluster ~850 L Radiative heating: of 6x10 6 L X-ray heating: 0.1 L (Tsujimoto et al 2006; Meijerink & Spaans 2005) Gas-grain heating: <30 L Mechanical & UV heating dominate

18 Radiation Field Tracers 14µm 21µm HCN HNC (Aalto et al 2015)

19 W49: Lines from Vibrational States Rotational lines in vibrationally excited states Four J=4-3 lines of HNC & HCN Plus HC 3 N 9 v6 lines 8 v7 lines 9 lines of SO 2 v2=1 IR pumped Extended First detection of HNC vibrational lines in a SFR H 13 CN HNC HCN HC 3 N v6=1 HC 3 N v7=1

20 W49: Excitation Conditions

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22 Kinematic Signatures? Shock tracers No clear kinematic signatures - Environments well mixed in beam

23 Comparison with other regions Galactic PDRs Galactic shocks PDR Models

24 W49: Extragalactic Comparison Physical Properties NGC1068 & M82 from results from Aladro et al 2011, 2013

25 W49: Extragalactic Comparison Chemical Properties NGC1068 & M82 from results from Aladro et al 2011, 2013

26 Recombination Line ALMA Cycle 0 Observations of NGC253 Belatto et al (2013), Leroy et al (2015), Meier et al 2015

27 NGC253: H40α (Bendo et al 2015) 1.9 x1.6 beam 28 pc Declination (J2000) -25:17:10-25:17: Jy km s -1 arcsec -2 I(H40 ) 00:47:34 00:47:33 Right Ascension (J2000)

28 Extinction & SFR Line to continuum ratio Need to correct for dust ~30% from dust T e = K Consistent with previous estimates and Milky Way GC If dust 50% of emission, T e = K SFR 1.73+/-0.12 M yr -1 Q=3.2+/- 0.2 x s -1 Density 10 3 cm -3 Previous values: <4.9 M yr -1 (SNR remnants 2.3 GHz Rampadarath et al 2014) 4.9 M yr -1 (25 GHz contiuum synchrotron calibration? Ott et al 2005) Q factor 3 above or below (Puxley et al 1997, Kepley et al 2011, Rodriguez-Rico et al 2006) Extinction Compare extinction predicted Brγ and Paβ with Engelbracht et al (1998) ALMA Measured A K 4.2+/ /-0.16 A J 5.0+/ /0.36

29 Velocity Structure Declination (J2000) -25:17:10-25:17: km s -1 v(h40 ) 00:47:34 00:47:33 Right Ascension (J2000) Rotation? Base of outflow?

30 Conclusions Spectral imaging survey of W49 covering GHz detecting 255 transitions of 63 species Excitation analysis of 14 species including complex species CH 3 CCH, CH 3 CN & CH 3 OH Chemistry driven by shocks & UV probably, but hard to disentangle W49 is a reasonable, but less extreme, analogue of an extragalactic starburst ALMA observations of H40α provide an estimate of SFR and extinction in NGC253 Roberts et al 2011; Nagy et al 2012, 2015; Bendo et al 2015