SWAN: Survey of Water & Ammonia in Nearby Galaxies Mark Gorski, Jürgen Ott, Richard Rand, David Meier, Emmanuel Momjian, Fabian Walter, Eva Schinnerer

Contents What is SWAN? Results NH3 Masers Conclusion

Galaxy Sample Galaxy D[MPC] SFR [M yr -1] Comments IC 342 3.0 1.5 Face on spiral NGC 6946 5.2 1.4 Face on spiral, buried nuclear SF NGC 253 3.5 5 Barred spiral, nucleated starburst NGC 2146 3.9 11 Peculiar barred spiral, LIRG(almost) SSRO/PROMPT/CTIO Range of SFR magnitudes. SFR here refers to nuclear starburst. IC 342 Is a milky way analog Star formation rates exceed that of the milky way in a sub region of these galaxies Brightest, more appropriate is fluxiest, galaxies. As a side note, for future studies, these galaxies span a range of SFR to use as templates to study High redshift galaxies. Laura Z. Working on Arp 220 T.A. Rector/University of Alaska Anchorage, H. Schweiker/WIYN and NOAO/AURA/NSF; Gemini Observatory/Travis Rector, University of Alaska Anchorage; SSRO/PROMPT/CTIO; T.A. Rector (University of Alaska Anchorage) and H. Schweiker (WIYN and NOAO/AURA/NSF)

Project Overview How does the galactic ecosystem change with SFR? How does SF influence the galactic environment? Reveal heating and cooling processes within a galaxy What is the anatomy of a galaxy? We can depict physical conditions inside a galaxy. Green is molecular gas Purple starbursts Yellow is outflow Stars are star forming regions Anatomy of a galaxy Meier and Turner 2005

NGC 253 in detail Distance= 3.5 Mpc Vsys=235 km s-1 Barred spiral galaxy Class: SABc Nucleated star burst ~3M yr-1 Total SFR ~5M yr-1 Molecular outflow rate ~9M yr-1 (Bolatto et al. 2013) 108 -109 M molecular mass Spitzer MIPS 24micron tracing the warm dust. .75 arcsec resolution

ALMA Molecular outflow Bolatto et al. 2013  Dense gas, shock tracers, and RRL, Meier et al. 2015  Diverse chemistry and structure traced by ALMA lines

Observations K and Ka band, D or C configurations Ammonia (1,1) to (5,5) transitions 23-25GHz Water(6-5) 22.3GHz Methanol(4-3) 36.2GHz Primary beam: ≈2 arcmin Resolution: ≈6x4 arcsec RMS: ≈ 0.6 mJy/chan 3.5 km/s /channel WIDAR Correlator Ammonia inversion unique to EVLA Alma mostly thermal rotational transitions EVLA masers

Spectra

26-37 GHz Ka Band

Molecular Tracers CO (Carbon Monoxide): 115.271 GHz Molecular Gas Tracer NH3 (Ammonia): 23.6945 – 27.4779 GHz Temperature and Dense Gas tracer. H2O (Water): 22.2351 GHz, Traces Shocks, collisionally excited maser. YSO, AGB stars, and AGN tori. CH3OH (Methanol): 36.1639 GHz, Class I maser, collisionally excited, shock tracer. Focus on

Ammonia Thermometry Rotation temperatures are derived from pairs of NH3 inversion lines Kinetic temperatures can be estimated from LVG models Peak Flux map of NH3 (3,3) C1 = Continuum peak

NH3 & CO NH3 follows CO gas fairly well

Temperature Structure L3 slightly absorbed 3,3 bump C1 derived from absorption spectrum

Temperature Structure Rotation Temperatures Trot(1,2): 36 ± 2 K Trot(2,4): 84 ± 5 K Trot(4,5): 104 ± 15 K Looks like there are 3 temperatures from fitting line pairs. But….

Temperature Structure LVG Extrapolation To Tkin LVG predicts T_rot fro a given Tkin. LVG extrapolation to Tkin predicts a “bend” in Boltzmann plots (Ott et al. 2011)

Temperature Structure Uniform Two Temperature Model Tkin(1,2): 57 ± 5 K Tkin(2,4): 134 ± 8 K Tkin(4,5): 117 ± 16 K Two uniform temperatures 130K and 57K Within 1 sigma errors we fit two temperatures across all of NGC253

Ammonia Masers NH3 masers span the centermost 250pc Bump in 3,3 line about the center Absorption in all lines but 3,3 NH3 masers span the centermost 250pc

Water masers 3 locations with water masers

Water Spectra LW1: 0.66 L LW2: >0.06 L LW3: 0.02 L All detections are >3sigma Luminosities are many orders of magnitude greater than Milky way at W1 Others are consistant with milkyway masers

Water masers (W1) Super resolved cube dramatizes the extended emission 100pc along the minor axis Brunthaler et al. 2009 reveal starburst nature with VLBA Velocities are consistent with models of outflow by Strickland et al. 2002 and Westmoquette et al. 2011 Predicted outflow velocities are of order 10^2 km/s VLBA observations show starburst nature not AGN brunthaler 2009

36 GHz Methanol 5 regions with masers

Methanol Spectra 5 distinct velocity components

Superbubbles CO (Bolatto et al. 2013), Superbubbles (Sakamoto et al 2016)

Masers and the Outflow Strickland et al. 2011 Putting this all together, we ask how do these masers relate to the outflow? Strickland et al. 2011

Conclusions Uniform two temperature distribution 130K and 57K Several new water maser Candidates Water maser extension seemingly along the outflow. Velocities match outflow cone models. New methanol masers possibly associated with shocks in super bubbles. No Temperature enhancement associated with super bubbles

Future Projects Apply the same analysis to the other three galaxies in the sample Look for relationships with star formation rates Relationships with other structures in galaxies Resolved studies of Ammonia, Methanol, and Water Masers

Questions