Subjects: Astronomy >> Astrophysical processes submitted time 2023-02-19
Jorge A. Zavala
Veronique Buat
Caitlin M. Casey
Denis Burgarella
Steven L. Finkelstein
Micaela B. Bagley
Laure Ciesla
Emanuele Daddi
Mark Dickinson
Henry C. Ferguson
Maximilien Franco
E. F. Jim'enez-Andrade
Jeyhan S. Kartaltepe
Anton M. Koekemoer
Aurélien Le Bail
E. J. Murphy
Casey Papovich
Sandro Tacchella
Stephen M. Wilkins
Itziar Aretxaga
Abstract： Lyman Break Galaxy (LBG) candidates at z>10 are rapidly being identified in JWST/NIRCam observations. Due to the (redshifted) break produced by neutral hydrogen absorption of rest-frame UV photons, these sources are expected to drop out in the bluer filters while being well detected in redder filters. However, here we show that dust-enshrouded star-forming galaxies at lower redshifts (z<7) may also mimic the near-infrared (near-IR) colors of z>10 LBGs, representing potential contaminants in LBG candidate samples. First, we analyze CEERS-DSFG-1, a NIRCam dropout undetected in the F115W and F150W filters but detected at longer wavelengths. Combining the JWST data with (sub)millimeter constraints, including deep NOEMA interferometric observations, we show that this source is a dusty star-forming galaxy (DSFG) at z~5.1. We also present a tentative 2.6sigma SCUBA-2 detection at 850um around a recently identified z~16 LBG candidate in the same field and show that, if the emission is real and associated with this candidate, the available photometry is consistent with a z~5 dusty galaxy with strong nebular emission lines despite its blue near-IR colors. Further observations on this candidate are imperative to mitigate the low confidence of this tentative submillimeter emission and its positional uncertainty. Our analysis shows that robust (sub)millimeter detections of NIRCam dropout galaxies likely imply z=4-6 redshift solutions, where the observed near-IR break would be the result of a strong rest-frame optical Balmer break combined with high dust attenuation and strong nebular line emission, rather than the rest-frame UV Lyman break. This provides evidence that DSFGs may contaminate searches for ultra high-redshift LBG candidates from JWST observations.
Peer Review Status:
Awaiting Review
Subjects: Astronomy >> Astrophysical processes submitted time 2023-02-19
Camilla Pacifici
Kartheik G. Iyer
Bahram Mobasher
Elisabete da Cunha
Viviana Acquaviva
Denis Burgarella
Gabriela Calistro Rivera
Adam C. Carnall
Yu-Yen Chang
Nima Chartab
Kevin C. Cooke
Ciaran Fairhurst
Jeyhan Kartaltepe
Joel Leja
Katarzyna Malek
Brett Salmon
Marianna Torelli
Alba Vidal-Garcia
Mederic Boquien
Gabriel G. Brammer
Abstract： The study of galaxy evolution hinges on our ability to interpret multi-wavelength galaxy observations in terms of their physical properties. To do this, we rely on spectral energy distribution (SED) models which allow us to infer physical parameters from spectrophotometric data. In recent years, thanks to the wide and deep multi-waveband galaxy surveys, the volume of high quality data have significantly increased. Alongside the increased data, algorithms performing SED fitting have improved, including better modeling prescriptions, newer templates, and more extensive sampling in wavelength space. We present a comprehensive analysis of different SED fitting codes including their methods and output with the aim of measuring the uncertainties caused by the modeling assumptions. We apply fourteen of the most commonly used SED fitting codes on samples from the CANDELS photometric catalogs at z~1 and z~3. We find agreement on the stellar mass, while we observe some discrepancies in the star formation rate (SFR) and dust attenuation results. To explore the differences and biases among the codes, we explore the impact of the various modeling assumptions as they are set in the codes (e.g., star formation histories, nebular, dust, and AGN models) on the derived stellar masses, SFRs, and A_V values. We then assess the difference among the codes on the SFR-stellar mass relation and we measure the contribution to the uncertainties by the modeling choices (i.e., the modeling uncertainties) in stellar mass (~0.1dex), SFR (~0.3dex), and dust attenuation (~0.3mag). Finally, we present some resources summarizing best practices in SED fitting.
Peer Review Status:Awaiting Review
Subjects: Astronomy >> Astrophysical processes submitted time 2023-02-19
Jeyhan S. Kartaltepe
Caitlin Rose
Brittany N. Vanderhoof
Elizabeth J. McGrath
Luca Costantin
Isabella G. Cox
L. Y. Aaron Yung
Dale D. Kocevski
Stijn Wuyts
Henry C. Ferguson Brett H. Andrews
Micaela B. Bagley
Steven L. Finkelstein
Ricardo O. Amorin
Pablo Arrabal Haro
Bren E. Backhaus
Peter Behroozi
Laura Bisigello
Antonello Calabro
Caitlin M. Casey
Rosemary T. Coogan
Abstract： We present a comprehensive analysis of the evolution of the morphological and structural properties of a large sample of galaxies at z=3-9 using early JWST CEERS NIRCam observations. Our sample consists of 850 galaxies at z>3 detected in both CANDELS HST imaging and JWST CEERS NIRCam images to enable a comparison of HST and JWST morphologies. Our team conducted a set of visual classifications, with each galaxy in the sample classified by three different individuals. We also measure quantitative morphologies using the publicly available codes across all seven NIRCam filters. Using these measurements, we present the fraction of galaxies of each morphological type as a function of redshift. Overall, we find that galaxies at z>3 have a wide diversity of morphologies. Galaxies with disks make up a total of 60\% of galaxies at z=3 and this fraction drops to ~30% at z=6-9, while galaxies with spheroids make up ~30-40% across the whole redshift range and pure spheroids with no evidence for disks or irregular features make up ~20%. The fraction of galaxies with irregular features is roughly constant at all redshifts (~40-50%), while those that are purely irregular increases from ~12% to ~20% at z>4.5. We note that these are apparent fractions as many selection effects impact the visibility of morphological features at high redshift. The distributions of S\'ersic index, size, and axis ratios show significant differences between the morphological groups. Spheroid Only galaxies have a higher S\'ersic index, smaller size, and higher axis ratio than Disk/Irregular galaxies. Across all redshifts, smaller spheroid and disk galaxies tend to be rounder. Overall, these trends suggest that galaxies with established disks and spheroids exist across the full redshift range of this study and further work with large samples at higher redshift is needed to quantify when these features first formed.
Peer Review Status:Awaiting Review
Subjects: Astronomy >> Astrophysical processes submitted time 2023-02-19
Vihang Mehta
Harry I. Teplitz
Claudia Scarlata
Xin Wang
Anahita Alavi
James Colbert
Marc Rafelski
Norman Grogin
Anton Koekemoer
Laura Prichard
Rogier Windhorst
Justin M. Barber
Christopher J. Conselice
Y. Sophia Dai
Jonathan P. Gardner
Eric Gawiser
Yicheng Guo
Nimish Hathi
Pablo Arrabal Haro
Matthew Hayes
Abstract： The UltraViolet imaging of the Cosmic Assembly Near-infrared Deep
Extragalactic Legacy Survey Fields (UVCANDELS) program provides HST/UVIS F275W
imaging for four CANDELS fields. We combine this UV imaging with existing
HST/near-IR grism spectroscopy from 3D-HST+AGHAST to directly compare the
resolved rest-frame UV and H$\alpha$ emission for a sample of 979 galaxies at
$0.7
Peer Review Status:Awaiting Review
Subjects: Astronomy >> Astrophysical processes submitted time 2023-02-19
Abdurro'uf
Dan Coe
Intae Jung
Henry C. Ferguson
Gabriel Brammer
Kartheik G. Iyer
Larry D. Bradley
Pratika Dayal
Rogier A. Windhorst
Adi Zitrin
Ashish Kumar Meena
Masamune Oguri
Jose M. Diego
Vasily Kokorev
Paola Dimauro
Angela Adamo
Christopher J. Conselice
Brian Welch
Eros Vanzella
Tiger Yu-Yang Hsiao
Abstract： We study the spatially resolved stellar populations of 444 galaxies at
$0.3
Peer Review Status:Awaiting Review
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