Examinando por Autor "Sun, F."

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Acceso Abierto
ALMA 1.3 mm Survey of Lensed Submillimeter Galaxies Selected by Herschel: Discovery of Spatially Extended SMGs and Implications
(IOP Science Publishing, 2021-02-24) Sun, F.; Egami, E.; Rawle, T. D.; Walth, G. L.; Smail, I.; Dessauges Zavadsky, M.; Pérez González, Pablo G.; Richard, J.; Combes, F.; Ebeling, H.; Pelló, R.; Werf, P. V.; Altieri, B.; Boone, F.; Cava, A.; Chapman, S. C.; Clément, B.; Finoguenov, A.; Nakajima, K.; Rujopakarn, W.; Schaerer, D.; Valtchanov, I.; Science and Technology Facilities Council (STFC); National Aeronautics and Space Administration (NASA); Sun, F. [0000-0002-4622-6617]; Rawle, T. D. [0000-0002-7028-5588]; Walth, G. L. [0000-0002-6313-6808]; Smail, I. [0000-0003-3037-257X]; Dessauges-Zavadsky, M. [0000-0003-0348-2917]; Pérez González, P. G. [0000-0003-4528-5639]; Richard, J. [0000-0001-5492-1049]; Combes, F. [0000-0003-2658-7893]; Ebeling, H. [0000-0001-8249-2739]; Pelló, R. [0000-0003-0858-6109]; Werf, P. V. [0000-0001-5434-5942]; Altieri, B. [0000-0003-3936-0284]; Cava, A. [0000-0002-4821-1275]; Finoguenov, A. [0000-0002-4606-5403]; Nakajima, K. [0000-0003-2965-5070]; Rujopakarn, W. [0000-0002-0303-499X]; Schaerer, D. [0000-0001-7144-7182]; Valtchanov, I. [0000-0001-9930-7886]
We present an ALMA 1.3 mm (Band 6) continuum survey of lensed submillimeter galaxies (SMGs) at z = 1.0 to ∼3.2 with an angular resolution of ∼0farcs2. These galaxies were uncovered by the Herschel Lensing Survey and feature exceptionally bright far-infrared continuum emission (Speak ≳ 90 mJy) owing to their lensing magnification. We detect 29 sources in 20 fields of massive galaxy clusters with ALMA. Using both the Spitzer/IRAC (3.6/4.5 μm) and ALMA data, we have successfully modeled the surface brightness profiles of 26 sources in the rest-frame near- and far-infrared. Similar to previous studies, we find the median dust-to-stellar continuum size ratio to be small (Re,dust/Re,star = 0.38 ± 0.14) for the observed SMGs, indicating that star formation is centrally concentrated. This is, however, not the case for two spatially extended main-sequence SMGs with a low surface brightness at 1.3 mm (≲0.1 mJy arcsec−2), in which the star formation is distributed over the entire galaxy (Re,dust/Re,star > 1). As a whole, our SMG sample shows a tight anticorrelation between (Re,dust/Re,star) and far-infrared surface brightness (ΣIR) over a factor of ≃1000 in ΣIR. This indicates that SMGs with less vigorous star formation (i.e., lower ΣIR) lack central starburst and are likely to retain a broader spatial distribution of star formation over the whole galaxies (i.e., larger Re,dust/Re,star). The same trend can be reproduced with cosmological simulations as a result of central starburst and potentially subsequent "inside-out" quenching, which likely accounts for the emergence of compact quiescent galaxies at z ∼ 2.
Restringido
Detection of the elusive dangling OH ice features at ~2.7 μm in Chamaeleon I with JWST NIRCam
(Nature Publishing Group, 2024-09-01) Noble, Jennifer; Fraser, Helen; Smith, Z. L.; Dartois, E.; Boogert, A. C. A.; Cuppen, Herma; Dickinson, Hugh J.; Dulieu, F.; Egami, E.; Erkal, Jessica; Giuliano, B. M.; Husquinet, Basile; Lamberts, T.; Maté, B.; McClure, Melissa; Palumbo, M. E.; Shimonishi, T.; Sun, F.; Bergner, Jennifer; Brown, Wendy; Caselli, P.; Congiu, E.; Drozdovskaya, Maria Nikolayevna; Herrero, V. J.; Ioppolo, Sergio; Jimenez-Serra, Izaskun; Linnartz, Harold; Melnick, G. J.; McGuire, Brett; Oberg, Karin; Perotti, G.; Qasim, D.; Rocha, Will Robson Monteiro; Urso, Riccardo Giovanni
Ascertaining the morphology and composition of the icy mantles covering dust grains in dense, cold regions of the interstellar medium is essential to developing accurate astrochemical models, determining conditions for ice formation, constraining chemical interactions in and on icy grains and understanding how ices withstand space radiation. The widely observed infrared spectroscopic signature of H2O ice at ~3 μm discriminates crystalline from amorphous structures in interstellar ices. Weaker bands seen only in laboratory ice spectra at ~2.7 μm, termed ‘dangling OH’ (dOH), are attributed to water molecules not fully bound to neighbouring water molecules and are often considered as tracing the degree of ice compaction. We exploit the high sensitivity of JWST NIRCam to detect two dOH features at 2.703 and 2.753 μm along multiple lines of sight probing the dense cloud Chamaeleon I, attributing these signatures to unbound dOH in cold water ice and dOH in interaction with other molecular species. These detections open a path to using the dOH features as tracers of the formation, composition, morphology and evolution of icy grains during the star and planet formation process.