Browsing by Author "Diaz-Santos, Tanio"

Now showing 1 - 4 of 4
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    A Hard X-Ray Test of HCN Enhancements As a Tracer of Embedded Black Hole Growth
    (2020) Privon, George C.; Ricci, Claudio; Aalto, S.; Viti, Serena; Armus, Lee; Diaz-Santos, Tanio; González-Alfonso, E.; Treister, Ezequiel; Bauer, Franz Erik; Garg, P.
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    CO (7-6), [C I] 370 mu m, and [N II] 205 mu m Line Emission of the QSO BRI1335-0417 at Redshift 4.407
    (2018) Lu, Nanyao; Cao, Tianwen; Diaz-Santos, Tanio; Zhao, Yinghe; Privon, George C.; Cheng, Cheng; Gao, Yu; Xu, C. Kevin; Charmandaris, Vassilis; Rigopoulou, Dimitra; Van der Werf, Paul P.; Huang, Jiasheng; Wang, Zhong; Evans, Aaron S.; Sanders, David B.
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    The ALMA-CRISTAL Survey: Spatially Resolved Star Formation Activity and Dust Content in 4 < z < 6 Star-forming Galaxies
    (2024) Li, Juno; Da Cunha, Elisabete; Gonzalez-Lopez, Jorge; Aravena, Manuel; De Looze, Ilse; Schreiber, N. M. Foerster; Herrera-Camus, Rodrigo; Spilker, Justin; Tadaki, Ken-ichi; Barcos-Munoz, Loreto; Battisti, Andrew J.; Birkin, Jack E.; Bowler, Rebecca A. A.; Davies, Rebecca; Diaz-Santos, Tanio; Ferrara, Andrea; Fisher, Deanne B.; Hodge, Jacqueline; Ikeda, Ryota; Killi, Meghana; Lee, Lilian; Liu, Daizhong; Lutz, Dieter; Mitsuhashi, Ikki; Naab, Thorsten; Posses, Ana; Relano, Monica; Solimano, Manuel; Uebler, Hannah; van der Giessen, Stefan Anthony; Villanueva, Vicente
    Using a combination of Hubble Space Telescope (HST), JWST, and Atacama Large Millimeter/submillimeter Array (ALMA) data, we perform spatially resolved spectral energy distributions (SED) fitting of fourteen 4 < z < 6 ultraviolet (UV)-selected main-sequence galaxies targeted by the ALMA Large Program [C ii] Resolved ISM in Star-forming Galaxies. We consistently model the emission from stars and dust in similar to 0.5-1 kpc spatial bins to obtain maps of their physical properties. We find no offsets between the stellar masses (M-*) and star formation rates (SFRs) derived from their global emission and those from adding up the values in our spatial bins, suggesting there is no bias of outshining by young stars on the derived global properties. We show that ALMA observations are important to derive robust parameter maps because they reduce the uncertainties in L-dust (hence, A(V) and SFR). Using these maps, we explore the resolved star-forming main sequence for z similar to 5 galaxies, finding that this relation persists in typical star-forming galaxies in the early Universe. We find less obscured star formation where the M-* (and SFR) surface densities are highest, typically in the central regions, contrary to the global relation between these parameters. We speculate this could be caused by feedback driving gas and dust out of these regions. However, more observations of IR luminosities with ALMA are needed to verify this. Finally, we test empirical SFR prescriptions based on the UV+IR and [C ii] line luminosity, finding they work well at the scales probed (approximately kiloparsec). Our work demonstrates the usefulness of joint HST-, JWST-, and ALMA-resolved SED modeling analyses at high redshift.
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    Warm Molecular Hydrogen in Nearby, Luminous Infrared Galaxies
    (2018) Petric, Andreea O.; Armus, Lee; Flagey, Nicolas; Guillard, Pierre; Howell, Justin; Inami, Hanae; Charmandaris, Vassillis; Evanss, Aaron; Stierwalt, Sabrina; Diaz-Santos, Tanio; Lu, Nanyao; Spoon, Henrik; Mazzarella, Joe; Appleton, Phil; Chan, Ben; Chu, Jason; Hand, Derek; Privon, George; Sanders, David; Surace, Jason; Xu, Kevin; Zhao, Yinghe
    Mid-infrared molecular hydrogen (H-2) emission is a powerful cooling agent in galaxy mergers and in radio galaxies; it is a potential key tracer of gas evolution and energy dissipation associated with mergers, star formation, and accretion onto supermassive black holes. We detect mid-IR H-2 line emission in at least one rotational transition in 91% of the 214 Luminous Infrared Galaxies (LIRGs) observed with Spitzer as part of the Great Observatories All-sky LIRG Survey. We use H-2 excitation diagrams to estimate the range of masses and temperatures of warm molecular gas in these galaxies. We find that LIRGs in which the IR emission originates mostly from the Active Galactic Nuclei (AGN) have about 100 K higher H-2 mass-averaged excitation temperatures than LIRGs in which the IR emission originates mostly from star formation. Between 10% and 15% of LIRGs have H-2 emission lines that are sufficiently broad to be resolved or partially resolved by the high-resolution modules of Spitzer's Infrared Spectrograph (IRS). Those sources tend to be mergers and contain AGN. This suggests that a significant fraction of the H-2 line emission is powered by AGN activity through X-rays, cosmic rays, and turbulence. We find a statistically significant correlation between the kinetic energy in the H-2 gas and the H-2 to IR luminosity ratio. The sources with the largest warm gas kinetic energies are mergers. We speculate that mergers increase the production of bulk inflows leading to observable broad H-2 profiles and possibly denser gas.