Browsing by Author "Schinnerer, E."

Now showing 1 - 4 of 4
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    A 33GHz Survey of Local Major Mergers: Estimating the Sizes of the Energetically Dominant Regions from High-resolution Measurements of the Radio Continuum
    (2017) Barcos-Munoz, L.; Leroy, A. K.; Evans, A. S.; Condon, J.; Privon, G. C.; Thompson, T. A.; Armus, L.; Diaz-Santos, T.; Mazzarella, J. M.; Meier, D. S.; Momjian, E.; Murphy, E. J.; Ott, J.; Sanders, D. B.; Schinnerer, E.; Stierwalt, S.; Surace, J. A.; Walter, F.
    We present Very Large Array observations of the 33 GHz radio continuum emission from 22 local ultraluminous and luminous infrared (IR) galaxies (U/LIRGs). These observations have spatial (angular) resolutions of 30-720 pc (0.'' 07-0.'' 67) in a part of the spectrum that is likely to be optically thin. This allows us to estimate the size of the energetically dominant regions. We find half-light radii from 30 pc to 1.7 kpc. The 33 GHz flux density correlates well with the IR emission, and we take these sizes as indicative of the size of the region that produces most of the energy. Combining our 33 GHz sizes with unresolved measurements, we estimate the IR luminosity and star formation rate per area and the molecular gas surface and volume densities. These quantities span a wide range (4 dex) and include some of the highest values measured for any galaxy (e.g., Sigma(33 GHz)(SFR) <= 10(4.1) M-circle dot yr(-1) kpc(-2)) at least 13 sources appear Compton thick (N-H(33 GHz) >= 10(24) cm(-2)). Consistent with previous work, contrasting these data with observations of normal disk galaxies suggests a nonlinear and likely multivalued relation between star formation rate and molecular gas surface density, though this result depends on the adopted CO-to-H-2 conversion factor and the assumption that our 33 GHz sizes apply to the gas. Eleven sources appear to exceed the luminosity surface density predicted for starbursts supported by radiation pressure and supernova feedback; however, we note the need for more detailed observations of the inner disk structure. U/LIRGs with higher surface brightness exhibit stronger [C II] 158 mu m deficits, consistent with the suggestion that high energy densities drive this phenomenon.
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    An ALMA survey of submillimetre galaxies in the COSMOS field : Physical properties derived from energy balance spectral energy distribution modelling
    (2017) Miettinen, O.; Delvecchio, I.; Smolčić, V.; Aravena, M.; Brisbin, D.; Karim, A.; Magnelli, B.; Novak, M.; Schinnerer, E.; Padilla, Nelson; Albrecht, M.; Aussel, H.; Bertoldi, F.; Capak, P.; Casey, C.; Hayward, C.; Ilbert , O.; Intema, H.; Jiang, C.; Le Fèvre, O.; McCracken, H.; Munõz Arancibia A.; Navarrete, F.; Riechers, D.|Salvato M.; Scott, K.; Sheth, K.; Tasca, L.
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    An ALMA survey of submillimetre galaxies in the COSMOS field : The extent of the radio-emitting region revealed by 3 GHz imaging with the Very Large Array
    (2017) Miettinen, O.; Novak, M.; Smolčić, V.; Delvecchio, I.; Aravena, M.; Brisbin, D.; Karim, A.; Murphy, E.; Schinnerer, E.; Padilla, Nelson; Albrecht, M.; Aussel, H.; Bertoldi, F.; Capak, P.; Casey, C.; Civano, F.; Hayward, C.; Herrera Ruiz, N.; Ilbert, O.; Jiang, C.; Laigle, C.; Le Fèvre, O.; Magnelli, B.; Marchesi, S.; McCracken, H.; Middelberg, E.; Muñoz Arancibia, A.; Navarrete, F.; Riechers, D.; Salvato, M.; Scott, K.; Sheth, K.; Tasca, L.; Bondi, M.; Zamorani, G.
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    An ALMA survey of submillimetre galaxies in the Extended Chandra Deep Field South: radio properties and the far-infrared/radio correlation
    (2014) Thomson, A. P.; Ivison, R. J.; Simpson, J. M.; Swinbank, A. M.; Smail, Ian; Arumugam, V.; Alexander, D. M.; Beelen, A.; Brandt, W. N.; Chandra, I.; Dannerbauer, H.; Greve, T. R.; Hodge, J. A.; Ibar, E.; Karim, A.; Murphy, E. J.; Schinnerer, E.; Sirothia, S.; Walter, F.; Wardlow, J. L.; van der Werf, P.
    We present a study of the radio properties of 870 mu m-selected submillimetre galaxies (SMGs), observed at high resolution with Atacama Large Millimeter Array (ALMA) in the Extended Chandra Deep Field South. From our initial sample of 76 ALMA SMGs, we detect 52 SMGs at >3 sigma significance in Karl G. Jansky Very Large Array 1400 MHz imaging, of which 35 are also detected at >3 sigma in new 610 MHz Giant Metre-Wave Radio Telescope imaging. Within this sample of radio-detected SMGs, we measure a median radio spectral index a alpha(1400)(610) = -0.79 +/- 0.06, (with inter-quartile range alpha = [-1.16, -0.56]) and investigate the far-infrared/radio correlation via the parameter q(IR), the logarithmic ratio of the rest-frame 8-1000 mu m flux and monochromatic radio flux. Our median q(IR) = 2.56 +/- 0.05 (inter-quartile range q(IR) = [2.42, 2.78]) is higher than that typically seen in single-dish 870 mu m-selected sources (q(IR) similar to 2.4), which may reflect the fact that our ALMA-based study is not biased to radio-bright counterparts, as previous samples were. Finally, we search for evidence that q(IR) and alpha evolve with age in a codependent manner, as predicted by starburst models: the data populate the predicted region of parameter space, with the stellar mass tending to increase along tracks of q(IR) versus alpha in the direction expected, providing the first observational evidence in support of these models.