papers

Publications (30)

astro-ph.GA2015

Spectroscopic detection of CIV in a galaxy at z=7.045: Implications for the ionizing spectra of reionization-era galaxies

Daniel P. Stark, Gregory Walth, Stephane Charlot +9

We present Keck/MOSFIRE observations of UV metal lines in four bright gravitationally-lensed z~6-8 galaxies behind the cluster Abell 1703. The spectrum of A1703-zd6, a highly-magni…

astro-ph.GA2018

RELICS: A Strong Lens Model for SPT-CLJ0615-5746, a z=0.972 Cluster

Rachel Paterno-Mahler, Keren Sharon, Dan Coe +30

We present a lens model for the cluster SPT-CLJ06155746, which is the highest redshift () system in the Reionization of Lensing Clusters Survey (RELICS), making it the…

astro-ph.GA2019

RELICS: Reionization Lensing Cluster Survey

Dan Coe, Brett Salmon, Marusa Bradac +54

Large surveys of galaxy clusters with the Hubble and Spitzer Space Telescopes, including CLASH and the Frontier Fields, have demonstrated the power of strong gravitational lensing…

astro-ph.GA2023

Spectroscopy of CASSOWARY gravitationally-lensed galaxies in SDSS: characterisation of an extremely bright reionization-era analog at

Ramesh Mainali, Daniel P. Stark, Tucker Jones +3

We present new observations of sixteen bright () gravitationally lensed galaxies at selected from the CASSOWARY survey. Included in our sample is the $z=1.42…

astro-ph.GA2019

UV Diagnostics of Galaxies from the Peak of Star-Formation to the Epoch of Reionization

Casey Papovich, Dan Stark, Steve Finkelstein +19

The rest-frame UV emission from massive stars contains a wealth of information about the physical nature and conditions of star formation in galaxies. Using studies of the rest-fra…

astro-ph.GA2023

A variable active galactic nucleus at triply-imaged by the galaxy cluster MACS J0035.4-2015

Lukas J. Furtak, Ramesh Mainali, Adi Zitrin +32

We report the discovery of a triply imaged active galactic nucleus (AGN), lensed by the galaxy cluster MACS J0035.4-2015 (). The object is detected in Hubble…

astro-ph.GA2020

RELICS: Spectroscopy of gravitationally-lensed reionization-era analogs and implications for CIII] detections at

Ramesh Mainali, Daniel P Stark, Mengtao Tang +17

Recent observations have revealed the presence of strong CIII] emission (EW Ã ) in galaxies, the origin of which remains unclear. In an effort to understand…

astro-ph.GA2023

JWST reveals a possible galaxy merger in triply-lensed MACS0647JD

Tiger Yu-Yang Hsiao, Dan Coe, Abdurro'uf +63

MACS0647JD is a triply-lensed galaxy originally discovered with the Hubble Space Telescope. Here we report new JWST imaging, which clearly resolves MACS0647JD as ha…

astro-ph.GA2022

The Cosmic Telescope that Lenses the Sunburst Arc, PSZ1 G311.65-18.48: Strong Gravitational Lensing model and Source Plane Analysis

Keren Sharon, Guillaume Mahler, T. Emil Rivera-Thorsen +12

We present a strong lensing analysis of the cluster PSZ1 G311.65-18.48, based on Hubble Space Telescope imaging, archival VLT/MUSE spectroscopy, and Chandra X-ray data. This cool-c…

astro-ph.GA2021

RELICS: Properties of z>5.5 Galaxies Inferred from Spitzer and Hubble Imaging Including A Candidate z~6.8 Strong [OIII] Emitter

Victoria Strait, Marusa Bradac, Dan Coe +26

We present constraints on the physical properties (including stellar mass, age, and star formation rate) of 207 galaxy candidates from the Reionization Lens…

astro-ph.GA2017

A spectroscopic search for AGN activity in the reionization era

Nicolas Laporte, Kimihiko Nakajima, Richard S. Ellis +4

The ubiquity of Lyman alpha (Ly) emission in a sample of four bright [O III]-strong star-forming galaxies with redshifts above 7 has led to the suggestion that such luminous so…

astro-ph.GA2018

Spectroscopic Constraints on UV Metal Line Emission at z~6-9: The Nature of Lyman-alpha Emitting Galaxies in the Reionization-Era

Ramesh Mainali, Adi Zitrin, Daniel P. Stark +6

Recent studies have revealed intense UV metal emission lines in a modest sample of z>7 Lyman-alpha emitters, indicating a hard ionizing spectrum is present. If such high ionization…

astro-ph.GA2024

Metal-poor star formation at with JWST: new insight into hard radiation fields and nitrogen enrichment on 20 pc scales

Michael W. Topping, Daniel P. Stark, Peter Senchyna +11

Nearly a decade ago, we began to see indications that reionization-era galaxies power hard radiation fields rarely seen at lower redshift. Most striking were detections of nebular…

astro-ph.GA2019

RELICS: Strong Lensing Analysis of MACS J0417.5-1154 and Predictions for Observing the Magnified High-Redshift Universe with JWST

Guillaume Mahler, Keren Sharon, Carter Fox +37

Strong gravitational lensing by clusters of galaxies probes the mass distribution at the core of each cluster and magnifies the universe behind it. MACS J0417.5-1154 at z=0.443 is…

astro-ph.CO2018

RELICS: Strong-lensing analysis of the massive clusters MACS J0308.9+2645 and PLCK G171.9-40.7

Ana Acebron, Nathália Cibirka, Adi Zitrin +37

Strong gravitational lensing by galaxy clusters has become a powerful tool for probing the high-redshift Universe, magnifying distant and faint background galaxies. Reliable strong…

astro-ph.CO2019

RELICS: High-Resolution Constraints on the Inner Mass Distribution of the z=0.83 Merging Cluster RXJ0152.7-1357 from strong lensing

Ana Acebron, May Alon, Adi Zitrin +37

Strong gravitational lensing (SL) is a powerful means to map the distribution of dark matter. In this work, we perform a SL analysis of the prominent X-ray cluster RXJ0152.7-1357 (…

astro-ph.GA2022

The connection between galactic outflows and the escape of ionizing photons

Ramesh Mainali, Jane R. Rigby, John Chisholm +13

We analyze spectra of a gravitationally lensed galaxy, known as the Sunburst Arc, that is leaking ionizing photons, also known as the Lyman continuum (LyC). Magnification from grav…

astro-ph.GA2018

Physical properties and H-ionizing-photon production rates of extreme nearby star-forming regions

Jacopo Chevallard, Stéphane Charlot, Peter Senchyna +7

Measurements of the galaxy UV luminosity function at z>6 suggest that young stars hosted in low-mass star-forming galaxies produced the bulk of hydrogen-ionizing photons necessary…

astro-ph.GA2017

Ultraviolet spectra of extreme nearby star-forming regions --- approaching a local reference sample for JWST

Peter Senchyna, Daniel P. Stark, Alba Vidal-García +7

Nearby dwarf galaxies provide a unique laboratory in which to test stellar population models below . Such tests are particularly important for interpreting the surprisin…

astro-ph.GA2018

RELICS: Strong Lens Models for Five Galaxy Clusters From the Reionization Lensing Cluster Survey

Catherine Cerny, Keren Sharon, Felipe Andrade-Santos +31

Strong gravitational lensing by galaxy clusters magnifies background galaxies, enhancing our ability to discover statistically significant samples of galaxies at z>6, in order to c…

astro-ph.GA2018

A bright lensed galaxy at with strong Ly emission

Ian D. McGreer, Benjamin Clément, Ramesh Mainali +10

We present a detailed study of a unusually bright, lensed galaxy at discovered within the CFHTLS imaging survey. With an observed flux of , J141446.82+54…

astro-ph.GA2024

Deep rest-UV JWST/NIRSpec spectroscopy of early galaxies: the demographics of CIV and N-emitters in the reionization era

Michael W. Topping, Daniel P. Stark, Peter Senchyna +12

JWST has recently discovered a subset of reionization era galaxies with ionized gas that is metal poor in oxygen and carbon but heavily-enriched in nitrogen. This abundance pattern…

astro-ph.GA2021

RELICS-DP7: Spectroscopic Confirmation of a Dichromatic Primeval Galaxy at z ~ 7

Debora Pelliccia, Victoria Strait, Brian C. Lemaux +12

We report the discovery of a spectroscopically-confirmed strong Lyman- emitter at , observed as part of the Reionization Cluster Lensing Survey (RELICS). Thi…

astro-ph.GA2018

A Candidate Galaxy Strongly Lensed into a Spatially Resolved Arc

Brett Salmon, Dan Coe, Larry Bradley +27

The most distant galaxies known are at z~10-11, observed 400-500 Myr after the Big Bang. The few z~10-11 candidates discovered to date have been exceptionally small- barely resolve…

astro-ph.CO2020

RELICS: A Very Large () Cluster Lens -- RXC J0032.1+1808

Ana Acebron, Adi Zitrin, Dan Coe +38

Extensive surveys with the \textit{Hubble Space Telescope} (HST) over the past decade, targeting some of the most massive clusters in the sky, have uncovered dozens of galaxy-clust…

astro-ph.CO2018

RELICS: Strong Lensing analysis of the galaxy clusters Abell S295, Abell 697, MACS J0025.4-1222, and MACS J0159.8-0849

Nathália Cibirka, Ana Acebron, Adi Zitrin +37

We present a strong-lensing analysis of four massive galaxy clusters imaged with the Hubble Space Telescope in the Reionization Lensing Cluster Survey. We use a Light-Traces-Mass t…

astro-ph.GA2023

Small Region, Big Impact: Highly Anisotropic Lyman-continuum Escape from a Compact Starburst Region with Extreme Physical Properties

Keunho J. Kim, Matthew B. Bayliss, Jane R. Rigby +13

Extreme, young stellar populations are considered the primary contributor to cosmic re-ionization. How Lyman-continuum (LyC) escapes these galaxies remains highly elusive, and it i…

astro-ph.GA2018

The Reionization Lensing Cluster Survey (RELICS) and the Brightest High-z Galaxies

Brett Salmon, Dan Coe, Larry Bradley +31

Massive foreground galaxy clusters magnify and distort the light of objects behind them, permitting a view into both the extremely distant and intrinsically faint galaxy population…

astro-ph.GA2017

Evidence for a Hard Ionizing Spectrum from a z=6.11 Stellar Population

Ramesh Mainali, Juna A. Kollmeier, Daniel P. Stark +4

We present the Magellan/FIRE detection of highly-ionized CIV 1550 and OIII] 1666 in a deep infrared spectrum of the z=6.11 gravitationally lensed low-mass galaxy RXC J2248.7-4431-I…

astro-ph.GA2016

Lyman-alpha and CIII] Emission in z=7-9 Galaxies: Accelerated Reionization Around Luminous Star Forming Systems?

Daniel P. Stark, Richard S. Ellis, Stephane Charlot +9

We discuss new Keck/MOSFIRE spectroscopic observations of four luminous galaxies at z~7-9 selected to have intense optical line emission by Roberts-Borsani et al. (2016). Previous…