Browsing by Author "Greve, T. R."

Now showing 1 - 3 of 3
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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.
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    SPT 0538-50: PHYSICAL CONDITIONS IN THE INTERSTELLAR MEDIUM OF A STRONGLY LENSED DUSTY STAR-FORMING GALAXY AT z=2.8
    (2013) Bothwell, M. S.; Aguirre, J. E.; Chapman, S. C.; Marrone, D. P.; Vieira, J. D.; Ashby, M. L. N.; Aravena, M.; Benson, B. A.; Bock, J. J.; Bradford, C. M.; Brodwin, M.; Carlstrom, J. E.; Crawford, T. M.; De Breuck, C.; Downes, T. P.; Fassnacht, C. D.; Gonzalez, A. H.; Greve, T. R.; Gullberg, B.; Hezaveh, Y.; Holder, G. P.; Holzapfel, W. L.; Ibar, E.; Ivison, R.; Kamenetzky, J.; Keisler, R.; Lupu, R. E.; Ma, J.; Malkan, M.; McIntyre, V.; Murphy, E. J.; Nguyen, H. T.; Reichardt, C. L.; Rosenman, M.; Spilker, J. S.; Stalder, B.; Stark, A. A.; Strandet, M.; Vernet, J.; Weiss, A.; Welikala, N.
    We present observations of SPT-S J053816-5030.8, a gravitationally lensed dusty star-forming galaxy (DSFG) at z = 2.7817 that was first discovered at millimeter wavelengths by the South Pole Telescope. SPT 0538-50 is typical of the brightest sources found by wide-field millimeter-wavelength surveys, being lensed by an intervening galaxy at moderate redshift (in this instance, at z = 0.441). We present a wide array of multi-wavelength spectroscopic and photometric data on SPT 0538-50, including data from ALMA, Herschel PACS and SPIRE, Hubble, Spitzer, the Very Large Telescope, ATCA, APEX, and the Submillimeter Array. We use high-resolution imaging from the Hubble Space Telescope to de-blend SPT 0538-50, separating DSFG emission from that of the foreground lens. Combined with a source model derived from ALMA imaging (which suggests a magnification factor of 21+/-4), we derive the intrinsic properties of SPT 0538-50, including the stellar mass, far-IR luminosity, star formation rate, molecular gas mass, and-using molecular line fluxes-the excitation conditions within the interstellar medium. The derived physical properties argue that we arewitnessing compact, merger-driven star formation in SPT 0538-50 similar to local starburst galaxies and unlike that seen in some other DSFGs at this epoch.
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    The Gas and Stellar Content of a Metal-poor Galaxy at z=8.496 as Revealed by JWST and ALMA
    (2023) Heintz, K. E.; Gimenez-Arteaga, C.; Fujimoto, S.; Brammer, G.; Espada, D.; Gillman, S.; Gonzalez-Lopez, J.; Greve, T. R.; Harikane, Y.; Hatsukade, B.; Knudsen, K. K.; Koekemoer, A. M.; Kohno, K.; Kokorev, V.; Lee, M. M.; Magdis, G. E.; Nelson, E. J.; Rizzo, F.; Sanders, R. L.; Schaerer, D.; Shapley, A. E.; Strait, V. B.; Toft, S.; Valentino, F.; van der Wel, A.; Vijayan, A. P.; Watson, D.; Bauer, F. E.; Christiansen, C. R.; Wilson, S. N.
    We present a joint analysis of the galaxy S04590 at z = 8.496 based on NIRSpec, NIRCam, and NIRISS observations obtained as part of the Early Release Observations program of the James Webb Space Telescope (JWST) and the far-infrared [C ii] 158 mu m emission line detected by dedicated Atacama Large Millimeter/submillimeter Array (ALMA) observations. We determine the physical properties of S04590 from modeling of the spectral energy distribution (SED) and through the redshifted optical nebular emission lines detected with JWST/NIRSpec. The best-fit SED model reveals a low-mass (M-? = 10(7.2)-10(8) M-?) galaxy with a low oxygen abundance of derived from the strong nebular and auroral emission lines. Assuming that [C ii] effectively traces the interstellar medium, we estimate the total gas mass of the galaxy to be M-gas = (8.0 +/- 4.0) x 10(8) M-? based on the luminosity and spatial extent of [C ii]. This yields an exceptionally high gas fraction, f(gas) = M-gas/(M-gas + M-?) ? 90%, though one still consistent with the range expected for low metallicity. We further derive the metal mass of the galaxy based on the gas mass and gas-phase metallicity, which we find to be consistent with the expected metal production from Type II supernovae. Finally, we make the first constraints on the dust-to-gas (DTG) and dust-to-metal (DTM) ratios of galaxies in the epoch of reionization at z ? 6, showing overall low mass ratios of logDTG < -3.8 and logDTM < -0.5, though they are consistent with established scaling relations and in particular with those of the local metal-poor galaxy I Zwicky 18. Our analysis highlights the synergy between ALMA and JWST in characterizing the gas, metal, and stellar content of the first generation of galaxies.