Physical Sciences and Mathematics Commons^™

Hsc-Clauds Survey: The Star Formation Rate Functions Since Z  ∼  2 And Comparison With Hydrodynamical Simulations, V. Picouet, S. Arnouts, E. Le Floc'h, T. Mountard, K. Kraljic, O. Illbert, M. Sawicki, G. Desprez, C. Laigle, D. Schiminovich, S. De La Torre, S. Gwyn, H. J. Mccracken, Y. Dobois, R. Davé, S. Toft, J. R. Weaver, M. Shuntov, O. B. Kauffmann

Astronomy Department Faculty Publication Series

Context. Star formation rate functions (SFRFs) give an instantaneous view of the distribution of star formation rates (SFRs) in galaxies at different epochs. They are a complementary and more stringent test for models than the galaxy stellar mass function, which gives an integrated view of the past star formation activity. However, the exploration of SFRFs has been limited thus far due to difficulties in assessing the SFR from observed quantities and probing the SFRF over a wide range of SFRs.

Aims. We overcome these limitations thanks to an original method that predicts the infrared luminosity from the rest-frame UV/optical color …

Unveiling The Nature Of Infrared Bright, Optically Dark Galaxies With Early Jwst Data, L Barrufet, P A. Oesch, A Weibel, G Brammer, R Bezanson, R Bouwens, Y Fudamoto, V Gonzalez, R Gottumkkala, G Illingworth, K E. Heintz, B Holden, I Labbe, D Magee, R P. Naidu, E Nelson, M Stefanon, R Smit, P Van Dokkum, J R. Weaver, C C. Williams

Astronomy Department Faculty Publication Series

Over the last few years, both Atacama Large Millimeter/submillimeter Array (ALMA) and Spitzer observations have revealed a population of likely massive galaxies at z > 3 that was too faint to be detected inHubble Space Telescope(HST) rest-frame ultraviolet imaging. However, due to the very limited photometry for individual galaxies, the true nature of these so-called HST-dark galaxies has remained elusive. Here, we present the first sample of such galaxies observed with very deep, high-resolution NIRCam imaging from the Early Release Science programme CEERS. 30 HST-dark sources are selected based on their red colours across 1.6–4.4 …

An Aromatic Inventory Of The Local Volume, Ar Marble, Cw Engelbracht, L Van Zee, Da Dale, Jdt Smith, Kd Gordon, Y Wu, Jc Lee, Rc Kennicutt, Ed Skillman, Lc Johnson, M Block, D Calzetti, Sa Cohen, H Lee, Md Schuster

Astronomy Department Faculty Publication Series

Using infrared photometry from the Spitzer Space Telescope, we perform the first inventory of aromatic feature emission (also commonly referred to as polycyclic aromatic hydrocarbon emission) for a statistically complete sample of star-forming galaxies in the local volume. The photometric methodology involved is calibrated and demonstrated to recover the aromatic fraction of the Infrared Array Camera 8 μm flux with a standard deviation of 6% for a training set of 40 SINGS galaxies (ranging from stellar to dust dominated) with both suitable mid-infrared Spitzer Infrared Spectrograph spectra and equivalent photometry. A potential factor of 2 improvement could be realized with …

The Calibration Of Monochromatic Far-Infrared Star Formation Rate Indicators, D Calzetti, Sy Wu, S Hong, Rc Kennicutt, Jc Lee, Da Dale, Cw Engelbracht, L Van Zee, Bt Draine, Cn Hao, Kd Gordon, J Moustakas, Ej Murphy, M Regan, A Begum, M Block, J Dalcanton, J Funes, Ag De Paz, B Johnson, S Sakai, E Skillman, F Walter, D Weisz, B Williams, Y Wu

Astronomy Department Faculty Publication Series

Spitzer data at 24, 70, and 160 μm and ground-based Hα images are analyzed for a sample of 189 nearby star-forming and starburst galaxies to investigate whether reliable star formation rate (SFR) indicators can be defined using the monochromatic infrared dust emission centered at 70 and 160 μm. We compare recently published recipes for SFR measures using combinations of the 24 μm and observed Hα luminosities with those using 24 μm luminosity alone. From these comparisons, we derive a reference SFR indicator for use in our analysis. Linear correlations between SFR and the 70 μm and 160 μm luminosity are …

Mid-Infrared Spectroscopy Of Candidate Active Galactic Nuclei-Dominated Submillimeter Galaxies, K Coppin, A Pope, K Menendez-Delmestre, Dm Alexander, Js Dunlop, E Egami, J Gabor, E Ibar, Rj Ivison, Je Austermann, Aw Blain, Sc Chapman, Dl Clements, L Dunne, S Dye, D Farrah, Dh Hughes, Amj Mortier, Mj Page, M Rowan-Robinson, D Scott, C Simpson, I Smail, Am Swinbank, M Vaccari, Min Yun

Astronomy Department Faculty Publication Series

Spitzer spectroscopy has revealed that 80% of submm galaxies (SMGs) are starburst (SB)-dominated in the mid-infrared. Here we focus on the remaining 20% that show signs of harboring powerful active galactic nuclei (AGNs). We have obtained Spitzer-InfraRed Spectrograph spectroscopy of a sample of eight SMGs that are candidates for harboring powerful AGNs on the basis of IRAC color selection (S _{8 μm}/S _{4.5 μm}>2, i.e., likely power-law mid-infrared spectral energy distributions). SMGs with an AGN dominating (50%) their mid-infrared emission could represent the "missing link" sources in an evolutionary sequence involving a major merger. First …

The Agn Fraction Of Submm-Selected Galaxies And Contributions To The Submm/Mm-Wave Extragalactic Background Light, S Serjeant, M Negrello, C Pearson, A Mortier, J Austermann, I Aretxaga, D Clements, S Chapman, S Dye, J Dunlop, L Dunne, D Farrah, D Hughes, Hm Lee, H Matsuhara, E Ibar, M Im, Ws Jeong, S Kim, S Oyabu, T Takagi, T Wada, G Wilson, M Vaccari, Min Yun

Astronomy Department Faculty Publication Series

We present a comparison of the SCUBA half degree extragalactic survey (SHADES) at 450 μm, 850 μm and 1100 μm with deep guaranteed time 15 μm AKARI FU-HYU survey data and Spitzer guaranteed time data at 3.6-24 μm in the Lockman hole east. The AKARI data was analysed using bespoke software based in part on the drizzling and minimum-variance matched filtering developed for SHADES, and was cross-calibrated against ISO fluxes. Our stacking analyses find AKARI 15 μm galaxies with 200 μJy contribute >10% of the 450 μm background, but only <4% of …

Two Bright Submillimeter Galaxies In A Z=4.05 Protocluster In Goods-North, And Accurate Radio-Infrared Photometric Redshifts, E Daddi, H Dannerbauer, D Stern, M Dickinson, G Morrison, D Elbaz, M Giavalisco, C Mancini, A Pope, H Spinrad

Astronomy Department Faculty Publication Series

No abstract provided.

An Aztec 1.1 Mm Survey Of The Goods-N Field - Ii. Multiwavelength Identifications And Redshift Distribution, El Chapin, A Pope, D Scott, I Aretxaga, Je Austermann, Rr Chary, K Coppin, M Halpern, Dh Hughes, Jd Lowenthal, Ge Morrison, Ta Perera, Ks Scott, Gw Wilson, Min Yun

Astronomy Department Faculty Publication Series

We present results from a multiwavelength study of 29 sources (false detection probabilities <5 per cent) from a survey of the Great Observatories Origins Deep Survey-North (GOODS-N) field at 1.1 mm using the Astronomical Thermal Emission Camera (AzTEC). Comparing with existing 850 μm Submillimetre Common-User Bolometer Array (SCUBA) studies in the field, we examine differences in the source populations selected at the two wavelengths. The AzTEC observations uniformly cover the entire survey field to a 1σ depth of ∼1 mJy. Searching deep 1.4 GHz Very Large Array (VLA) and Spitzer 3–24 μm catalogues, we identify robust counterparts for 21 1.1 mm sources, and tentative associations for the remaining objects. The redshift distribution of AzTEC sources is inferred from available spectroscopic and photometric redshifts. We find a median redshift of z= 2.7, somewhat higher than z= 2.0 for 850 μm selected sources in the same field, and our lowest redshift identification lies at a spectroscopic redshift z= 1.1460. We measure the 850 μm to 1.1 mm colour of our sources and do not find …

Star-Forming Or Starbursting? The Ultraviolet Conundrum, M Boquien, D Calzetti, R Kennicutt, D Dale, C Engelbracht, Kd Gordon, S Hong, Jc Lee, J Portouw

Astronomy Department Faculty Publication Series

Compared to starburst galaxies, normal star-forming galaxies have been shown to display a much larger dispersion of the dust attenuation at fixed reddening through studies of the IRX-β diagram (the IR/UV ratio "IRX" versus the UV color "β"). To investigate the causes of this larger dispersion and attempt to isolate second parameters, we have used GALEX UV, ground-based optical, and Spitzer infrared imaging of eight nearby galaxies, and examined the properties of individual UV and 24 μm selected star-forming regions. We concentrated on star-forming regions, in order to isolate simpler star formation histories than those that characterize whole galaxies. We …

The Spitzer Local Volume Legacy: Survey Description And Infrared Photometry, Da Dale, Sa Cohen, Lc Johnson, Md Schuster, D Calzetti, Cw Engelbracht, Ag De Paz, Rc Kennicutt, Jc Lee, A Begum, M Block, Jj Dalcanton, Jg Funes, Kd Gordon, Bd Johnson, Ar Marble, S Sakai, Ed Skillman, L Van Zee, F Walter, Dr Weisz, B Williams, Sy Wu, Y Wu

Astronomy Department Faculty Publication Series

The survey description and the near-, mid-, and far-infrared flux properties are presented for the 258 galaxies in the Local Volume Legacy (LVL). LVL is a Spitzer Space Telescope legacy program that surveys the local universe out to 11 Mpc, built upon a foundation of ultraviolet, Hα, and Hubble Space Telescope imaging from 11HUGS (11 Mpc Hα and Ultraviolet Galaxy Survey) and ANGST (ACS Nearby Galaxy Survey Treasury). LVL covers an unbiased, representative, and statistically robust sample of nearby star-forming galaxies, exploiting the highest extragalactic spatial resolution achievable with Spitzer. As a result of its approximately volume-limited nature, LVL augments …

Aztec Millimetre Survey Of The Cosmos Field - Ii. Source Count Overdensity And Correlations With Large-Scale Structure, Je Austermann, I Aretxaga, Dh Hughes, Y Kang, S Kim, Jd Lowenthal, Ta Perera, Db Sanders, Ks Scott, N Scoville, Gw Wilson, Min Yun

Astronomy Department Faculty Publication Series

We report an overdensity of bright submillimetre galaxies (SMGs) in the 0.15 deg² AzTEC/COSMOS survey and a spatial correlation between the SMGs and the optical-IR galaxy density at z≲ 1.1. This portion of the COSMOS field shows a ∼3σ overdensity of robust SMG detections when compared to a background, or ‘blank-field’, population model that is consistent with SMG surveys of fields with no extragalactic bias. The SMG overdensity is most significant in the number of very bright detections (14 sources with measured fluxes S_{1.1 mm} > 6 mJy), which is entirely incompatible with sample variance within our adopted …

Spitzer Irac Infrared Colours Of Submillimetre-Bright Galaxies, Min Yun, I Aretxaga, Mln Ashby, J Austermann, Gg Fazio, M Giavalisco, Js Huang, Dh Hughes, S Kim, Jd Lowenthal, T Perera, K Scott, G Wilson, Jd Younger

Astronomy Department Faculty Publication Series

High-redshift submillimetre-bright galaxies identified by blank field surveys at millimetre and submillimetre wavelengths appear in the region of the Infra Red Array Camera (IRAC) colour–colour diagrams previously identified as the domain of luminous active galactic nuclei (AGNs). Our analysis using a set of empirical and theoretical dusty starburst spectral energy distribution (SED) models shows that power-law continuum sources associated with hot dust heated by young (≲100 Myr old), extreme starbursts at z > 2 also occupy the same general area as AGNs in the IRAC colour–colour plots. A detailed comparison of the IRAC colours and SEDs demonstrates that the two populations …