Browsing by Author "Diaz Santos, T."

Now showing 1 - 7 of 7
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    A Herschel/PACS Far-infrared Line Emission Survey of Local Luminous Infrared Galaxies
    (IOP PUBLISHING LTD, 2017) Diaz Santos, T.; Armus, L.; Charmandaris, V.; Lu, N.; Stierwalt, S.; Stacey, G.; Malhotra, S.; van der Werf, P. P.; Howell, J. H.; Privon, G. C.; Mazzarella, J. M.; Goldsmith, P. F.; Murphy, E. J.; Barcos Munoz, L.; Linden, S. T.; Inami, H.; Larson, L.; Evans, A. S.; Appleton, P.; Iwasawa, K.; Lord, S.; Sanders, D. B.; Surace, J. A.
    We present an analysis of [O I](63), [O III](88), [N II](122), and [C II](158) far-infrared (FIR) fine-structure line observations obtained with Herschel/PACS, for similar to 240 local luminous infrared galaxies (LIRGs) in the Great Observatories All-sky LIRG Survey. We find pronounced declines ("deficits") of line-to-FIR continuum emission for [N II](122), [O I](63), and [C II](158) as a function of FIR color and infrared luminosity surface density, Sigma(IR). The median electron density of the ionized gas in LIRGs, based on the [N II](122)/[N II](205) ratio, is n(e) = 41 cm(-3). We find that the dispersion in the [C II](158) deficit of LIRGs is attributed to a varying fractional contribution of photodissociation regions (PDRs) to the observed [C II](158) emission, f ([C II](158)(PDR)) = [C II](158)(PDR)/C II](158), which increases from similar to 60% to similar to 95% in the warmest LIRGs. The [O I](63)/[C II](158)(PDR) ratio is tightly correlated with the PDR gas kinetic temperaturein sources where [O I] 63 is not optically thick or self-absorbed. For each galaxy, we derive the average PDR hydrogen density, n(H), and intensity of the interstellar radiation field, G, in units of G(0) and find G/n(H) ratios of similar to 0.1-50 G(0) cm(3), with ULIRGs populating the upper end of the distribution. There is a relation between G/n(H) and Sigma(IR), showing a critical break at Sigma(IR)* similar or equal to 5 x 10(10) L-circle dot kpc(-2). Below Sigma(IR)*, G/n(H) remains constant, similar or equal to 0.32G(0) cm(3), and variations in Sigma(IR) are driven by the number density of star-forming regions within a galaxy, with no change in their PDR properties. Above Sigma(IR)*, G/n(H) increases rapidly with Sigma(IR), signaling a departure from the typical PDR conditions found in normal star-forming galaxies toward more intense/harder radiation fields and compact geometries typical of starbursting sources.
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    Massive Star Cluster Formation and Destruction in Luminous Infrared Galaxies in GOALS
    (IOP PUBLISHING LTD, 2017) Linden, S. T.; Evans, A. S.; Rich, J.; Larson, K. L.; Armus, L.; Diaz Santos, T.; Privon, G. C.; Howell, J.; Inami, H.; Kim, D. C.; Chien, L. H.; Vavilkin, T.; Mazzarella, J. M.; Modica, F.; Surace, J. A.; Manning, S.; Abdullah, A.; Blake, A.; Yarber, A.; Lambert, T.
    We present the results of a Hubble Space Telescope ACS/HRC FUV, ACS/WFC optical study into the cluster populations of a sample of 22 Luminous Infrared Galaxies in the Great Observatories All-Sky LIRG Survey. Through integrated broadband photometry, we have derived ages and masses for a total of 484 star clusters contained within these systems. This allows us to examine the properties of star clusters found in the extreme environments of LIRGs relative to lower luminosity star-forming galaxies in the local universe. We find that by adopting a Bruzual & Charlot simple stellar population model and Salpeter initial mass function, the age distribution of the clusters declines as dN/d tau = tau(-0.9+/-0.3), consistent with the age distribution derived for the Antennae Galaxies, and interpreted as evidence for rapid cluster disruption occurring in the strong tidal fields of merging galaxies. The large number of 10(6) M-circle dot young clusters identified in the sample also suggests that LIRGs are capable of producing more high-mass clusters than what is observed to date in any lower luminosity star-forming galaxy in the local universe. The observed cluster mass distribution of dN/dM = M-1.95+/-0.11 is consistent with the canonical -2 power law used to describe the underlying initial cluster mass function (ICMF) for a wide range of galactic environments. We interpret this as evidence against mass-dependent cluster disruption, which would flatten the observed CMF relative to the underlying ICMF distribution.
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    The ALMA Spectroscopic Survey in the Hubble Ultra Deep Field : CO Excitation and Atomic Carbon in Star-forming Galaxies at z=1-3
    (2020) Boogaard, L. A.; van der Werf, P.; Weiss, A.; Popping, G.; Decarli, R.; Walter, F.; Aravena, M.; Bouwens, R.; Riechers, D.; González López, Jorge; Smail, I.; Carilli, C.; Kaasinen, M.; Daddi, E.; Cox, P.; Diaz Santos, T.; Inami, H.; Cortes, P. C.; Wagg, J.
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    The ALMA Spectroscopic Survey in the Hubble Ultra Deep Field : The Nature of the Faintest Dusty Star-forming Galaxies
    (2020) Aravena, M.; Boogaard, L.; Gonzalez-Lopez, J.; Decarli, R.; Walter, F.; Carilli, C. L.; Smail, I.; Weiss, A.; Assef, R. J.; Bauer, Franz Erik; Bouwens, R. J.; Cortes, P. C.; Cox, P.; da Cunha, E.; Daddi, E.; Diaz Santos, T.; Inami, H.; Ivison, R.; Novak, M.; Popping, G.; Riechers, D.; van der Werf, P.; Wagg, J.
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    The ALMA Spectroscopic Survey in the Hubble Ultra Deep Field: Constraining the Molecular Content at log (M-*/M-circle dot) ∼ 9.5 with CO Stacking of MUSE-detected z ∼ 1.5 Galaxies
    (2020) Inami, H.; Decarli, R.; Walter, F.; Weiss, A.; Carilli, C.; Aravena, M.; Boogaard, L.; González López, Jorge; Popping, G.; Bauer, Franz Erik; da Cunha, E.; Bacon, R.; Contini, T.; Cortes, P. C.; Cox, P.; Daddi, E.; Diaz Santos, T.; Kaasinen, M.; Riechers, D. A.; Wagg, J.; van der Werf, P.; Wisotzki, L.
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    The ALMA Spectroscopic Survey in the HUDF : Deep 1.2 mm Continuum Number Counts
    (2020) Gonzalez Lopez, J.; Novak, M.; Decarli, R.; Walter, F.; Aravena, M.; Carilli, C.; Boogaard, L.; Popping, G.; Weiss, A.; Bauer, Franz Erik; Assef, R. J.; Bouwens, R.; Cortes, P. C.; Cox, P.; Daddi, E.; Cunha, E.; Diaz Santos, T.; Ivison, R.; Magnelli, B.; Riechers, D.; Smail, I.; van der Werf, P.; Wagg, J.
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    The ALMA Spectroscopic Survey in the HUDF : The Cosmic Dust and Gas Mass Densities in Galaxies up to z ∼ 3
    (2020) Magnelli, B.; Boogaard, L.; Decarli, R.; Gonzalez Lopez, J.; Novak, M.; Popping, G.; Smail, I.; Walter, F.; Aravena, M.; Bauer, Franz Erik; Assef, R. J.; Bertoldi, F.; Carilli, C.; Cortes, P. C.; da Cunha, E.; Daddi, E.; Diaz Santos, T.; Inami, H.; Ivison, R. J.; Le Fevre, O.; Oesch, P.; Riechers, D.; Rix, H. W.; Sargent, M. T.; van der Werf, P.; Wagg, J.; Weiss, A.