Publications (54)
UVCANDELS: Catalogs of photometric redshifts and galaxy physical properties
Vihang Mehta, Marc Rafelski, Ben Sunnquist +76
The UltraViolet imaging of the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey Fields (UVCANDELS) program provides deep HST F275W and F435W imaging over four CANDELS…
Evolution of Gas, and Star Formation from z = 0 to 5
Nick Scoville, Andreas Faisst, John Weaver +20
ALMA observations of the long wavelength dust continuum are used to estimate the gas masses in a sample of 708 star-forming (SF) galaxies at z = 0.3 to 4.5. We determine the depend…
Optical Spectroscopy of Dwarf Galaxies at in the COSMOS Field: Star Formation and Dust Properties
Zahra Sattari, Daniel D. Kelson, Bahram Mobasher +4
We present a spectroscopic study of low-mass galaxies (LMGs;) at in COSMOS field, and compare it to a control sample of intermediate-ma…
Learning to See Sharper: A Physics-Informed Artificial Intelligence Framework for Super-Resolving Galaxy Spectra
Aryana Haghjoo, Shoubaneh Hemmati, Bahram Mobasher +6
The information recoverable from galaxy spectra depends fundamentally on spectral resolution, yet assembling large samples at high resolution remains observationally expensive. We…
DEIMOS spectroscopy of protocluster candidate in COSMOS -- A massive protocluster embedded in a large scale structure?
Malte Brinch, Thomas R. Greve, David B. Sanders +14
We present the results of our Keck/DEIMOS spectroscopic follow-up of candidate galaxies of i-band-dropout protocluster candidate galaxies at in the COSMOS field. We secure…
Spatially resolved properties of galaxies from CANDELS+MUSE: Radial extinction profile and insights on quenching
Marziye Jafariyazani, Bahram Mobasher, Shoubaneh Hemmati +3
Studying the internal processes of individual galaxies at kilo-parsec scales is crucial in enhancing our understanding of galaxy formation and evolution processes. In this work, we…
LATIS: The Stellar Mass-Metallicity Relation of Star-forming Galaxies at
Nima Chartab, Andrew B. Newman, Gwen C. Rudie +2
We present the stellar mass - stellar metallicity relation for 3491 star-forming galaxies at using rest-frame far-ultraviolet (FUV) spectra from the Ly$α…
Bridging between the integrated and resolved main sequence of star formation
Shoubaneh Hemmati, Bahram Mobasher, Hooshang Nayyeri +6
The position of galaxies on the stellar mass, star formation rate plane with respect to the star-forming main sequence at each redshift is a convenient way to infer where the galax…
COSMOS Spectroscopic Redshift Compilation (First Data Release): 488k Redshifts Encompassing Two Decades of Spectroscopy
Ali Ahmad Khostovan, Jeyhan S. Kartaltepe, Mara Salvato +54
We present the COSMOS Spectroscopic Redshift Compilation encompassing ~ 20 years of spectroscopic redshifts within a 10 deg area centered on the 2 deg COSMOS legacy field.…
A Machine Learning Approach to Predict Missing Flux Densities in Multi-band Galaxy Surveys
Nima Chartab, Bahram Mobasher, Asantha Cooray +21
We present a new method based on information theory to find the optimal number of bands required to measure the physical properties of galaxies with a desired accuracy. As a proof…
COSMOS-Web: Comprehensive Data Reduction for Wide-Area JWST NIRCam Imaging
Maximilien Franco, Caitlin M. Casey, Anton M. Koekemoer +37
We present the data reduction methodology used for the COSMOS-Web survey JWST NIRCam data. Covering 0.54 deg^2 with four broadband filters (F115W, F150W, F277W, F444W) and a total…
Leveraging Machine Learning for Accurate and Fast Stellar Mass Estimation of Galaxies
Vahid Asadi, Akram Hasani Zonoozi, Hosein Haghi +4
Unveiling the evolutionary history of galaxies necessitates a precise understanding of their physical properties. Traditionally, astronomers achieve this through spectral energy di…
Galaxy Zoo: Cosmic Dawn -- morphological classifications for over 41,000 galaxies in the Euclid Deep Field North from the Hawaii Two-0 Cosmic Dawn survey
James Pearson, Hugh Dickinson, Stephen Serjeant +22
We present morphological classifications of over 41,000 galaxies out to across six square degrees of the Euclid Deep Field North (EDFN) from the Hawaii Twenty…
Introducing the Texas Euclid Survey for Lyman Alpha (TESLA) Survey: Initial Study Correlating Galaxy Properties to Lyman-Alpha Emission
Oscar A. Chavez Ortiz, Steven L. Finkelstein, Dustin Davis +24
We present the Texas Euclid Survey for Lyman-Alpha (TESLA), a spectroscopic survey in the 10 square degree of the Euclid North Ecliptic Pole (NEP) field. Using TESLA, we study how…
LATIS Data Release: Spectra of Galaxies, Redshifts, and Intergalactic Medium Tomography Maps
Andrew B. Newman, Gwen C. Rudie, Guillermo A. Blanc +8
We present the data release of the Ly Tomography IMACS Survey (LATIS), one of the largest optical spectroscopic surveys of faint high-redshift galaxies. The survey provides 740…
UV-Bright Star-Forming Clumps and Their Host Galaxies in UVCANDELS at 0.5 z 1
Alec Martin, Yicheng Guo, Xin Wang +32
Giant star-forming clumps are a prominent feature of star-forming galaxies (SFGs) and contain important clues on galaxy formation and evolution. However, basic demographics of clum…
COSMOS Web: Morphological quenching and size-mass evolution of brightest group galaxies from z = 3.7
Ghassem Gozaliasl, Lilan Yang, Jeyhan Kartaltepe +47
We present a comprehensive study of the structural evolution of Brightest Group Galaxies (BGGs) from redshift to using the \textit{James Webb Space Telesc…
COSMOS-Web: An Overview of the JWST Cosmic Origins Survey
Caitlin M. Casey, Jeyhan S. Kartaltepe, Nicole E. Drakos +82
We present the survey design, implementation, and outlook for COSMOS-Web, a 255 hour treasury program conducted by the James Webb Space Telescope in its first cycle of observations…
Application of Manifold Learning to Selection of Different Galaxy Populations and Scaling Relation Analysis
Sogol Sanjaripour, Shoubaneh Hemmati, Bahram Mobasher +8
The growing volume of data produced by large astronomical surveys necessitates the development of efficient analysis techniques capable of effectively managing high-dimensional dat…
Crimson Behemoth: a Massive Clumpy Structure Hosting a Dusty AGN at
Takumi S. Tanaka, John D. Silverman, Yurina Nakazato +40
The current paradigm for the co-evolution of galaxies and their supermassive black holes postulates that dust-obscured active galactic nuclei (AGNs) represent a transitional phase…
Dynamics of Star-forming Galaxies in a Massive Structure at \lowercase{} 2.2: Evidence for Galaxy Harassment in high- Environments
Behnam Darvish, Nima Chartab, Zahra Sattari +5
We spectroscopically confirm a new protocluster in the COSMOS field at =2.24430 with Keck/MOSFIRE, dubbed CC2.2B, which is in the immediate vicinity of CC2.2A protocluster, orig…
Spectroscopic Confirmation of a Coma Cluster Progenitor at z ~ 2.2
Behnam Darvish, Nick Z. Scoville, Christopher Martin +17
We report the spectroscopic confirmation of a new protocluster in the COSMOS field at 2.2, COSMOS Cluster 2.2 (CC2.2), originally identified as an overdensity of narrowb…
LATIS: A Sample of IGM-selected Protoclusters and Protogroups at
Andrew B. Newman, Mahdi Qezlou, Gwen C. Rudie +11
The Ly Tomography IMACS Survey (LATIS) has produced large 3D maps of the intergalactic medium (IGM), providing a new window on the cosmic web at . A key advantage of…
The MOSDEF Survey: Environmental dependence of the gas-phase metallicity of galaxies at
Nima Chartab, Bahram Mobasher, Alice E. Shapley +13
Using the near-IR spectroscopy of the MOSFIRE Deep Evolution Field (MOSDEF) survey, we investigate the role of local environment in the gas-phase metallicity of galaxies. The local…
Evidence for gas-phase metal deficiency in massive protocluster galaxies at z~2.2
Zahra Sattari, Bahram Mobasher, Nima Chartab +4
We study the mass-metallicity relation for 19 members of a spectroscopically-confirmed protocluster in the COSMOS field at (CC2.2), and compare it with that of 24 similarly…
Investigating the Effect of Galaxy Interactions on AGN Enhancement at
Ekta A. Shah, Jeyhan S. Kartaltepe, Christina T. Magagnoli +30
Galaxy interactions and mergers are thought to play an important role in the evolution of galaxies. Studies in the nearby universe show a higher AGN fraction in interacting and mer…
Searching for Quiescent Galaxies over in JWST Surveys Using Manifold Learning
Alexander de la Vega, Mitchell D. Babcock, Bahram Mobasher +5
Quiescent galaxies over are rare and puzzling. They formed and quenched within two billion years and simulations routinely struggle to predict their observed abundances. De…
Selection of massive evolved galaxies at in the CANDELS fields
Abtin Shahidi, Bahram Mobasher, Hooshang Nayyeri +14
Using the CANDELS photometric catalogs for the HST/ACS and WFC3, we identified massive evolved galaxies at , employing three different selection methods. We find the c…
Gas Phase Metallicities of Local Ultra-Luminous Infrared Galaxies Follow Normal Star-Forming Galaxies
Nima Chartab, Asantha Cooray, Jingzhe Ma +9
Despite advances in observational data, theoretical models, and computational techniques to simulate key physical processes in the formation and evolution of galaxies, the stellar…
Dependence of the IRX- dust attenuation relation on metallicity and environment
Irene Shivaei, Behnam Darvish, Zahra Sattari +4
We use a sample of star-forming field and protocluster galaxies at z=2.0-2.5 with Keck/MOSFIRE K-band spectra, a wealth of rest-frame UV photometry, and Spitzer/MIPS and Herschel/P…
SCUBADive I: JWST+ALMA Analysis of 289 sub-millimeter galaxies in COSMOS-Web
Jed McKinney, Caitlin M. Casey, Arianna S. Long +36
JWST has enabled detecting and spatially resolving the heavily dust-attenuated stellar populations of sub-millimeter galaxies, revealing detail that was previously inaccessible. In…
Comparison of Observed Galaxy Properties with Semianalytic Model Predictions using Machine Learning
Melanie Simet, Nima Chartab, Yu Lu +1
With current and upcoming experiments such as WFIRST, Euclid and LSST, we can observe up to billions of galaxies. While such surveys cannot obtain spectra for all observed galaxies…
The Lyman Continuum Escape Fraction of Star-forming Galaxies at from UVCANDELS
Xin Wang, Harry I. Teplitz, Brent M. Smith +74
The UltraViolet Imaging of the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey Fields (UVCANDELS) survey is a Hubble Space Telescope (HST) Cycle-26 Treasury Program,…
BEACON: JWST NIRCam Pure-parallel Imaging Survey. IV. A Systematic Search for Galaxy Overdensities and Evidence for Gas Accretion Mode Transition
Ryo Albert Sutanto, Takahiro Morishita, Tadayuki Kodama +20
We systematically search for galaxy overdensities using 20 independent fields with a minimum of six filters (F090W, F115W, F150W, F277W, F356W, and F444W) from BEACON, the JWST Cyc…
Large-Scale Structure in COSMOS-Web: Tracing Galaxy Evolution in the Cosmic Web up to with the Largest JWST Survey
Hossein Hatamnia, Bahram Mobasher, Sina Taamoli +31
We present a reconstruction of the large-scale structure using the James Webb Space Telescope's (JWST) COSMOS-Web program to trace environmentally driven galaxy evolution up to $z\…
LATIS: Galaxy-Environment Relations at Cosmic Noon and the Role of Sample Selection
Nima Chartab, Andrew B. Newman, Gwen C. Rudie +6
We investigate the environmental dependence of galaxy properties at using the Ly Tomography IMACS Survey (LATIS), which provides high-resolution three-dimensional ma…
Large Scale Structures in the CANDELS Fields: The Role of the Environment in Star Formation Activity
Nima Chartab, Bahram Mobasher, Behnam Darvish +14
We present a robust method, weighted von Mises kernel density estimation, along with boundary correction to reconstruct the underlying number density field of galaxies. We apply th…
Exploring the Correlation between -to-UV Ratio and Burstiness for Typical Star-forming Galaxies at
Saeed Rezaee, Naveen A. Reddy, Michael W. Topping +12
The -to-UV luminosity ratio () is often used to probe SFHs of star-forming galaxies and it is important to validate it against other proxies for bur…
Investigating the Effect of Galaxy Interactions on Star Formation at 0.5<z<3.0
Ekta A. Shah, Jeyhan S. Kartaltepe, Christina T. Magagnoli +24
Observations and simulations of interacting galaxies and mergers in the local universe have shown that interactions can significantly enhance the star formation rates (SFR) and fue…
The UV luminosity function at 0.6 < z < 1 from UVCANDELS
Lei Sun, Xin Wang, Harry I. Teplitz +75
UVCANDELS is a HST Cycle-26 Treasury Program awarded 164 orbits of primary ultraviolet (UV) F275W imaging and coordinated parallel optical F435W imaging in four CANDELS fields: GOO…
Large Scale Structures in COSMOS2020: Evolution of Star Formation Activity in Different Environments at 0.4 < z < 4
Sina Taamoli, Bahram Mobasher, Nima Chartab +15
To study the role of environment in galaxy evolution, we reconstruct the underlying density field of galaxies based on COSMOS2020 (The Farmer catalog) and provide the density catal…
Fraction of Clumpy Star-Forming Galaxies at in UVCANDELS: Dependence on Stellar Mass and Environment
Zahra Sattari, Bahram Mobasher, Nima Chartab +25
High-resolution imaging of galaxies in rest-frame UV has revealed the existence of giant star-forming clumps prevalent in high redshift galaxies. Studying these sub-structures prov…
COSMOS2020: Disentangling the Role of Mass and Environment in Star Formation Activity of Galaxies at
Sina Taamoli, Negin Nezhad, Bahram Mobasher +14
The role of internal and environmental factors in the star formation activity of galaxies is still a matter of debate, particularly at higher redshifts. Leveraging the most recent…
UVCANDELS: The role of dust on the stellar mass-size relation of disk galaxies at 0.5 3.0
Kalina V. Nedkova, Marc Rafelski, Harry I. Teplitz +30
We use the Ultraviolet Imaging of the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey fields (UVCANDELS) to measure half-light radii in the rest-frame far-UV for $\s…
COSMOS2025: The COSMOS-Web galaxy catalog of photometry, morphology, redshifts, and physical parameters from JWST, HST, and ground-based imaging
Marko Shuntov, Hollis B. Akins, Louise Paquereau +55
We present COSMOS2025, the COSMOS-Web catalog of photometry, morphology, photometric redshifts and physical parameters for more than 700,000 galaxies in the Cosmic Evolution Survey…
LATIS: Comparing Galaxy and IGM Tomography Maps as Tracers of Large-scale Structure and Protoclusters at
Andrew B. Newman, Nima Chartab, Mahdi Qezlou +11
We investigate the consistency of intergalactic medium (IGM) tomography and galaxy surveys as tracers of the cosmic web and protoclusters at . We use maps from the Ly$Î…
LATIS: Constraints on the Galaxy-halo Connection at from Galaxy-galaxy and Galaxy-Ly Clustering
Andrew B. Newman, Mahdi Qezlou, Nima Chartab +6
The connection between galaxies and dark matter halos is often quantified using the stellar mass-halo mass (SMHM) relation. Optical and near-infrared imaging surveys have led to a…
Investigating the Dominant Environmental Quenching Process in UVCANDELS/COSMOS Groups
Maxwell Kuschel, Claudia Scarlata, Vihang Mehta +36
We explore how the fraction of quenched galaxies changes in groups of galaxies with respect to the distance to the center of the group, redshift, and stellar mass to determine the…
The Fraction of Clumpy Galaxies in JADES Over
Alexander de la Vega, Bahram Mobasher, Zahra Sattari +3
High-redshift galaxies exhibit compact regions of intense star formation, known as ``clumps,'' which are conspicuous in the rest-frame ultraviolet. Studying them can shed light on…
The Art of Measuring Physical Parameters in Galaxies: A Critical Assessment of Spectral Energy Distribution Fitting Techniques
Camilla Pacifici, Kartheik G. Iyer, Bahram Mobasher +52
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…
Optimized Photometric Redshifts for the Cosmic Assembly Near-Infrared Deep Extragalactic Legacy Survey (CANDELS)
Dritan Kodra, Brett H. Andrews, Jeffrey A. Newman +27
We present the first comprehensive release of photometric redshifts (photo-z's) from the Cosmic Assembly Near-Infrared Deep Extragalactic Legacy Survey (CANDELS) team. We use stati…
Empirical Calibration of Na I D and Other Absorption Lines as Tracers of High-Redshift Neutral Outflows
Lorenzo Moretti, Sirio Belli, Gwen C. Rudie +5
Recent JWST observations of massive galaxies at z > 2 have detected blueshifted absorption in Na I D and other resonant absorption lines, indicative of strong gas outflows in the n…
Accelerated Emergence of Evolved Galaxies in Early Overdensities at
Takahiro Morishita, Zhaoran Liu, Massimo Stiavelli +8
We report the identification of two galaxy overdensities at in the sightline of the galaxy cluster Abell 2744. These overdensities consist of 25 and 17 member galaxies,…
Machine Learning Classification of COSMOS2020 Galaxies: Quiescent vs. Star-Forming
Vahid Asadi, Nima Chartab, Akram Hasani Zonoozi +4
Accurately distinguishing between quiescent and star-forming galaxies is essential for understanding galaxy evolution. Traditional methods, such as spectral energy distribution (SE…