Research
Magnifying the Distant Universe
My research is concerned with distant galaxies, so far away that their light has taken most of the age of the Universe to reach us. In particular, I use the effect of gravitational lensing to magnify distant galaxies so that we can study them in more detail.
Below, you will find my most commonly referenced figures, with downloadable, machine-readable data tables, as well as a full publications list.
The UV Luminosity Function at z > 6

Observations of the galaxy population at z > 6 (seen during the first billion years after the Big Bang) indicate that the faint-end slope of the UV luminosity function is steep (α ~ -2), suggesting that faint galaxies may have dominated the ionizing photon budget during reionization. This motivates understanding the faint-end slope, and determining the lower magnitude limit towards which it extends. Using gravitational lensing, we can find these ultra-faint galaxies. So far, there is no evidence of a turnover in the luminosity function to limits as low as MUV ~ -13 at z ~ 6.
Luminosity function data points are downloadable in ASCII format here:
z ~ 6; z ~ 7; z ~ 8
Star forming clumps in gravitationally lensed galaxies

Observations of distant galaxies have revealed a population quite unlike that found in the local Universe; at high redshift, galaxies form stars more rapidly than they do locally, and their morphologies are often dominated by large clumps. While large-scale statistical studies can reveal these trends in overall properties, a detailed understanding of the processes involved in galaxy evolution in the early Universe requires high-resolution, spatially-resolved data.
My PhD research focused on using gravitational lensing to achieve the required spatial resolution in galaxies at 1 < z < 4. By targeting distant galaxies that lie behind massive foreground clusters, we are able to benefit from lensing magnification factors of up to 50x, resulting in spatial resolution of order ~100pc. Thus, we can isolate individual clumps or HII regions in high-redshift galaxies with 'normal' luminosities and star formation rates for their redshift, and study them in unprecedented detail.
Data on the star-forming clumps I observed is downloadable in ASCII format here:
From Livermore et al. (2012): HST narrowband imaging of galaxies at 1 < z < 1.5. Contains clump size and star formation rate.
From Livermore et al. (2015): integral field spectroscopy of galaxies at 1 < z < 4. Contains clump size, star formation rate and velocity dispersion.
Publications
Automatically retrieved from ADS.- VizieR Online Data Catalog: RELICS: Reionization Lensing Cluster Survey (Coe+, 2019)
Coe, Salmon, Bradac, ..., Livermore, et al., 2021,
VizieR On-line Data Catalog: J/ApJ/884/85. Originally published in: 2019ApJ...884...85C
ADS Link
- The Sizes of z ∼ 9-10 Galaxies Identified in the Brightest of Reionizing Galaxies (BoRG) Survey
Holwerda, Bridge, Steele, ..., Livermore, et al., 2020,
The Astronomical Journal, Volume 160, Issue 4, id.154, 9 pp.
ADS Link
- The Sizes of z\sim9-10 Galaxies Identified in the BoRG Survey
Holwerda, Bridge, Steele, ..., Livermore, et al., 2020,
eprint arXiv:2005.03515
ADS Link
- RELICS: Reionization Lensing Cluster Survey
Coe, Salmon, Bradač, ..., Livermore, et al., 2019,
The Astrophysical Journal, Volume 884, Issue 1, article id. 85, 24 pp. (2019).
ADS Link
- The brightest galaxies in the first 700 Myr: Building Hubble's legacy of large area IR imaging for JWST and beyond
Trenti, Bernard, Bouwens, ..., Livermore, et al., 2019,
HST Proposal. Cycle 26, ID. #16005
ADS Link
- Conditions for Reionizing the Universe with a Low Galaxy Ionizing Photon Escape Fraction
Finkelstein, D'Aloisio, Paardekooper, ..., Livermore, et al., 2019,
The Astrophysical Journal, Volume 879, Issue 1, article id. 36, 34 pp. (2019).
ADS Link
- On the observability of individual Population III stars and their stellar-mass black hole accretion disks through cluster caustic transits
Windhorst, Alpaslan, Andrews, ..., Livermore, et al., 2019,
Astro2020: Decadal Survey on Astronomy and Astrophysics, science white papers, no. 449; Bulletin of the American Astronomical Society, Vol. 51, Issue 3, id. 449 (2019)
ADS Link
- RELICS: High-resolution Constraints on the Inner Mass Distribution of the z = 0.83 Merging Cluster RXJ0152.7-1357 from Strong Lensing
Acebron, Alon, Zitrin, ..., Livermore, et al., 2019,
The Astrophysical Journal, Volume 874, Issue 2, article id. 132, 13 pp. (2019).
ADS Link
- RELICS: Strong Lensing Analysis of MACS J0417.5-1154 and Predictions for Observing the Magnified High-redshift Universe with JWST
Mahler, Sharon, Fox, ..., Livermore, et al., 2019,
The Astrophysical Journal, Volume 873, Issue 1, article id. 96, 15 pp. (2019).
ADS Link
- Observational determination of the galaxy bias from cosmic variance with a random pointing survey: clustering of z ∼ 2 galaxies from Hubble's BoRG survey
Cameron, Trenti, Livermore, et al., 2019,
Monthly Notices of the Royal Astronomical Society, Volume 483, Issue 2, p.1922-1933
ADS Link
- PLCK G165.7+67.0: Analysis of a Massive Lensing Cluster in a Hubble Space Telescope Census of Submillimeter Giant Arcs Selected Using Planck/Herschel
Frye, Pascale, Qin, ..., Livermore, et al., 2019,
The Astrophysical Journal, Volume 871, Issue 1, article id. 51, 21 pp. (2019).
ADS Link
- Heterogeneity and Variability of "Astronomy on Tap" Public Outreach Events
Rice, Livermore, Silverman, et al., 2019,
American Astronomical Society, AAS Meeting #233, id.244.05
ADS Link
- The Bright-end Galaxy Candidates at z ∼ 9 from 79 Independent HST Fields
Morishita, Trenti, Stiavelli, ..., Livermore, et al., 2018,
The Astrophysical Journal, Volume 867, Issue 2, article id. 150, 18 pp. (2018).
ADS Link
- The brightest galaxies in the first 700 Myr: Building Hubble's legacy of large area IR imaging for JWST and beyond
Trenti, Bernard, Bouwens, ..., Livermore, et al., 2018,
HST Proposal. Cycle 26, ID. #16005
ADS Link
- Texas Spectroscopic Search for Lyα Emission at the End of Reionization I. Constraining the Lyα Equivalent-width Distribution at 6.0 < z < 7.0
Jung, Finkelstein, Livermore, et al., 2018,
The Astrophysical Journal, Volume 864, Issue 2, article id. 103, 15 pp. (2018).
ADS Link
- RELICS: A Strong Lens Model for SPT-CLJ0615-5746, a z = 0.972 Cluster
Paterno-Mahler, Sharon, Coe, ..., Livermore, et al., 2018,
The Astrophysical Journal, Volume 863, Issue 2, article id. 154, 11 pp. (2018).
ADS Link
- RELICS: Strong Lensing Analysis of the Galaxy Clusters Abell S295, Abell 697, MACS J0025.4-1222, and MACS J0159.8-0849
Cibirka, Acebron, Zitrin, ..., Livermore, et al., 2018,
The Astrophysical Journal, Volume 863, Issue 2, article id. 145, 25 pp. (2018).
ADS Link
- HST Follow-up Observations of Two Bright z ∼ 8 Candidate Galaxies from the BoRG Pure-parallel Survey
Livermore, Trenti, Bradley, et al., 2018,
The Astrophysical Journal Letters, Volume 861, Issue 2, article id. L17, 5 pp. (2018).
ADS Link
- RELICS: Strong-lensing Analysis of the Massive Clusters MACS J0308.9+2645 and PLCK G171.9-40.7
Acebron, Cibirka, Zitrin, ..., Livermore, et al., 2018,
The Astrophysical Journal, Volume 858, Issue 1, article id. 42, 13 pp. (2018).
ADS Link
- RELICS: Reionization Lensing Cluster Survey - Discovering Brightly Lensed Distant Galaxies for JWST
Coe, Bradley, Salmon, ..., Livermore, et al., 2018,
American Astronomical Society, AAS Meeting #231, id. 454.10
ADS Link
- Tackling The Dragon: Investigating Lensed Galaxy Structure
Fortenberry, Livermore, 2018,
American Astronomical Society, AAS Meeting #231, id. 153.24
ADS Link
- The Faint End of the Lyman Alpha Luminosity Function at 2 < z < 3.8
Devarakonda, Livermore, Indahl, et al., 2018,
American Astronomical Society, AAS Meeting #231, id. 149.25
ADS Link
- VizieR Online Data Catalog: Galaxies >~6 from the Hubble Frontier Fields (Livermore+, 2017)
Livermore, Finkelstein, Lotz, 2017,
VizieR On-line Data Catalog: J/ApJ/835/113. Originally published in: 2017ApJ...835..113L
ADS Link
- Star Formation at z = 2.481 in the Lensed Galaxy SDSS J1110+6459: Star Formation Down to 30 pc Scales
Johnson, Rigby, Sharon, ..., Livermore, et al., 2017,
The Astrophysical Journal Letters, Volume 843, Issue 2, article id. L21, 5 pp. (2017).
ADS Link
- A Magnified View of the Epoch of Reionization with the Hubble Frontier Fields
Livermore, Finkelstein, Lotz, 2017,
American Astronomical Society, AAS Meeting #230, id.316.10
ADS Link
- Constraining the End of Reionization with Deep Lyman-alpha Spectroscopy
Jung, Finkelstein, Livermore, et al., 2017,
American Astronomical Society, AAS Meeting #230, id.316.08
ADS Link
- JWST Medium-Deep Fields - Windhorst IDS GTO Program
Windhorst, Alpaslan, Ashcraft, ..., Livermore, et al., 2017,
JWST Proposal. Cycle 1, ID. #1176
ADS Link
- Directly Observing the Galaxies Likely Responsible for Reionization
Livermore, Finkelstein, Lotz, 2017,
The Astrophysical Journal, Volume 835, Issue 2, article id. 113, 21 pp. (2017).
ADS Link
- The minimum halo mass for star formation at z = 6-8
Finlator, Prescott, Oppenheimer, ..., Livermore, et al., 2017,
Monthly Notices of the Royal Astronomical Society, Volume 464, Issue 2, p.1633-1639
ADS Link
- Constraining Metallicity and Age for Massive Quiescent Galaxies in a Redshift Range of 1
Estrada-Carpenter, Papovich, Momcheva, ..., Livermore, et al., 2017,
American Astronomical Society, AAS Meeting #229, id.347.25
ADS Link
- First Simultaneous Detection of Lyman-alpha Emission and Lyman Break from a Galaxy at Redshift 7.51 from Faint Infrared Grism Survey (FIGS)
Tilvi, Pirzkal, Malhotra, ..., Livermore, et al., 2017,
American Astronomical Society, AAS Meeting #229, id.347.08
ADS Link
- A New Semi-Empirical Model of Reionization
Finkelstein, Paardekooper, Behroozi, ..., Livermore, 2017,
American Astronomical Society, AAS Meeting #229, id.347.04
ADS Link
- The Expanding Universe of Astronomy on Tap
Livermore, Morris, Narayan, et al., 2017,
American Astronomical Society, AAS Meeting #229, id.335.11
ADS Link
- The UV Luminosity Function at 6 < z < 10 from the Hubble Frontier Fields
Livermore, Finkelstein, Lotz, 2017,
American Astronomical Society, AAS Meeting #229, id.141.09
ADS Link
- ALMA Reveals Large Molecular Gas Reservoirs in Ancestors of Milky Way-Mass Galaxies at z=1.2-1.3
Papovich, Labbe, Glazebrook, ..., Livermore, et al., 2017,
American Astronomical Society, AAS Meeting #229, id.132.01
ADS Link
- Large molecular gas reservoirs in ancestors of Milky Way-mass galaxies nine billion years ago
Papovich, Labbé, Glazebrook, ..., Livermore, et al., 2016,
Nature Astronomy, Volume 1, id. 0003 (2016).
ADS Link
- First Results from the Faint Infrared Grism Survey (FIGS): First Simultaneous Detection of Lyα Emission and Lyman Break from a Galaxy at z = 7.51
Tilvi, Pirzkal, Malhotra, ..., Livermore, et al., 2016,
The Astrophysical Journal Letters, Volume 827, Issue 1, article id. L14, 6 pp. (2016).
ADS Link
- Keck/MOSFIRE Spectroscopy of z = 7-8 Galaxies: Lyα Emission from a Galaxy at z = 7.66
Song, Finkelstein, Livermore, et al., 2016,
The Astrophysical Journal, Volume 826, Issue 2, article id. 113, 9 pp. (2016).
ADS Link
- Caught in the Act: Gas and Stellar Velocity Dispersions in a Fast Quenching Compact Star-Forming Galaxy at z~1.7
Barro, Faber, Dekel, ..., Livermore, et al., 2016,
The Astrophysical Journal, Volume 820, Issue 2, article id. 120, 16 pp. (2016).
ADS Link
- VizieR Online Data Catalog: HST Frontier Fields clusters (Richard+, 2014)
Richard, Jauzac, Limousin, ..., Livermore, et al., 2016,
VizieR On-line Data Catalog: J/MNRAS/444/268. Originally published in: 2014MNRAS.444..268R
ADS Link
- The CANDELS Lyman-alpha Emission At Reionization (CLEAR) Experiment
Papovich, Brammer, Dickinson, ..., Livermore, et al., 2016,
HST Proposal. Cycle 23, ID. #14227
ADS Link
- Pushing the Frontiers: uncovering the earliest galaxies in the Hubble Frontier Fields
Livermore, 2016,
Astronomy in Focus, as presented at the IAU XXIX General Assembly, 2015. Proceedings of the IAU, Volume 29B, 2016, pp. 812-815
ADS Link
- A Sneak Peek at the JWST Era: Observing Galaxies Below the Hubble Limit with Gravitational Lensing
Livermore, 2016,
American Astronomical Society, AAS Meeting #227, id.342.53
ADS Link
- Expanding the Universe of "Astronomy on Tap" Public Outreach Events
Rice, Levine, Livermore, et al., 2016,
American Astronomical Society, AAS Meeting #227, id.248.02
ADS Link
- Searching for faint high-z galaxies in the Hubble Frontier Fields
Livermore, 2015,
HST Proposal id.14300. Cycle 23
ADS Link
- The Evolution of the Galaxy Rest-frame Ultraviolet Luminosity Function over the First Two Billion Years
Finkelstein, Ryan, Papovich, ..., Livermore, et al., 2015,
The Astrophysical Journal, Volume 810, Issue 1, article id. 71, 35 pp. (2015).
ADS Link
- Astronomy on Tap: science engagement in the pub
Livermore, Silverman, 2015,
IAU General Assembly, Meeting #29, id.2257428
ADS Link
- Galaxies in the Epoch of Reionization
Livermore, 2015,
IAU General Assembly, Meeting #29, id.2257245
ADS Link
- Pushing the Frontiers: uncovering the earliest galaxies in the Hubble Frontier Fields
Livermore, 2015,
IAU General Assembly, Meeting #29, id.2257202
ADS Link
- Probing Bursty Star Formation in Faint Galaxies with the Hubble Frontier Fields
Finkelstein, Livermore, Song, 2015,
IAU General Assembly, Meeting #29, id.2247292
ADS Link
- Resolved spectroscopy of gravitationally lensed galaxies: global dynamics and star-forming clumps on ∼100 pc scales at 1 < z < 4
Livermore, Jones, Richard, et al., 2015,
Monthly Notices of the Royal Astronomical Society, Volume 450, Issue 2, p.1812-1835
ADS Link
- Searching the Sky for the Brightest Galaxies in the Distant Universe
Finkelstein, Diekmann, Finkelstein, ..., Livermore, 2014,
Spitzer Proposal ID 11121
ADS Link
- Keck-I MOSFIRE Spectroscopy of Compact Star-forming Galaxies at z >~ 2: High Velocity Dispersions in Progenitors of Compact Quiescent Galaxies
Barro, Trump, Koo, ..., Livermore, et al., 2014,
The Astrophysical Journal, Volume 795, Issue 2, article id. 145, 12 pp. (2014).
ADS Link
- Mass and magnification maps for the Hubble Space Telescope Frontier Fields clusters: implications for high-redshift studies
Richard, Jauzac, Limousin, ..., Livermore, et al., 2014,
Monthly Notices of the Royal Astronomical Society, Volume 444, Issue 1, p.268-289
ADS Link
- Galaxies in the epoch of reionization
Livermore, 2014,
Keck Observatory Archive DEIMOS, id.N168D
ADS Link
- The HETDEX Pilot Survey. V. The Physical Origin of Lyα Emitters Probed by Near-infrared Spectroscopy
Song, Finkelstein, Gebhardt, ..., Livermore, et al., 2014,
The Astrophysical Journal, Volume 791, Issue 1, article id. 3, 24 pp. (2014).
ADS Link
- Completing the Galaxy Census from z=0 to z~7 in the CANDELS/COSMOS Field
Tilvi, Papovich, Finkelstein, ..., Livermore, et al., 2014,
NOAO Proposal ID 2014A-0236
ADS Link
- Galaxies Under the Cosmic Microscope
Livermore, 2014,
American Astronomical Society, AAS Meeting #223, id.133.05
ADS Link
- Harnessing the Power of Gravitational Lensing: Resolved Star Formation at 1 < z < 5
Livermore, 2013,
PhD Thesis, Durham University, 2013
ADS Link
- High-resolution Study of the Cluster Complexes in a Lensed Spiral at Redshift 1.5: Constraints on the Bulge Formation and Disk Evolution
Adamo, Östlin, Bastian, ..., Livermore, et al., 2013,
The Astrophysical Journal, Volume 766, Issue 2, article id. 105, 16 pp. (2013).
ADS Link
- Harnessing the power of gravitational lensing: Resolved star formation at 1< z < 4
Livermore, 2013,
PhD Thesis, Durham University, 2013
ADS Link
- Hubble Space Telescope Hα imaging of star-forming galaxies at z ≃ 1-1.5: evolution in the size and luminosity of giant H II regions
Livermore, Jones, Richard, et al., 2012,
Monthly Notices of the Royal Astronomical Society, Volume 427, Issue 1, pp. 688-702.
ADS Link
- Observational Limits on the Gas Mass of a z = 4.9 Galaxy
Livermore, Swinbank, Smail, et al., 2012,
The Astrophysical Journal Letters, Volume 758, Issue 2, article id. L35, 5 pp. (2012).
ADS Link
- The emission line properties of gravitationally lensed 1.5 < z < 5 galaxies
Richard, Jones, Ellis, ..., Livermore, et al., 2011,
Monthly Notices of the Royal Astronomical Society, Volume 413, Issue 1, pp. 643-658.
ADS Link
- Metallicity Gradient of a Lensed Face-on Spiral Galaxy at Redshift 1.49
Yuan, Kewley, Swinbank, ..., Livermore, 2011,
The Astrophysical Journal Letters, Volume 732, Issue 1, article id. L14, 5 pp. (2011).
ADS Link