Jakob M. Helton
A5015899497- Galaxies: Formation, Evolution, Phenomena
- Astronomy and Astrophysical Research
- Stellar, planetary, and galactic studies
- Astrophysics and Star Formation Studies
- Gamma-ray bursts and supernovae
- Adaptive optics and wavefront sensing
- Astrophysical Phenomena and Observations
- Computational Physics and Python Applications
- Astronomical Observations and Instrumentation
- CCD and CMOS Imaging Sensors
- Radio Astronomy Observations and Technology
- Geophysics and Gravity Measurements
- Cosmology and Gravitation Theories
- Black Holes and Theoretical Physics
- Solar and Space Plasma Dynamics
- Relativity and Gravitational Theory
- Scientific Research and Discoveries
- Astrophysics and Cosmic Phenomena
- Spectroscopy and Laser Applications
- Impact of Light on Environment and Health
- Superconducting and THz Device Technology
- Calibration and Measurement Techniques
- Polydiacetylene-based materials and applications
- Spectroscopy and Chemometric Analyses
- Radiation Therapy and Dosimetry
University of Arizona
2021-2025
Princeton University
2020-2022
We present new arcminute-resolution maps of the Cosmic Microwave Background temperature and polarization anisotropy from Atacama Cosmology Telescope, using data taken 2013-2016 at 98 150 GHz. The cover more than 17,000 deg$^2$, deepest 600 deg$^2$ with noise levels below 10 $\mu$K-arcmin. use power spectrum derived almost 6,000 these to constrain cosmology. ACT enable a measurement angular scale features in both divergence-like anisotropy, tracing velocity density last-scattering. From one...
We present JADES JWST/NIRSpec spectroscopy of GN-z11, the most luminous candidate z > 10 Lyman break galaxy in GOODS-North field with M UV = −21.5. derive a redshift 10.603 (lower than previous determinations) based on multiple emission lines our low and medium resolution spectra over 0.7 − 5.3 μm. significantly detect continuum measure blue rest-UV spectral slope β −2.4. Remarkably, we see spatially extended Lyman- α (despite highly neutral intergalactic expected at this early epoch),...
Several theories have been proposed to describe the formation of black hole seeds in early Universe and explain emergence very massive holes observed first thousand million years after Big Bang
We present JWST NIRCam 9-band near-infrared imaging of the luminous $z=10.6$ galaxy GN-z11 from Advanced Deep Extragalactic Survey (JADES) GOODS-N field. find a spectral energy distribution (SED) entirely consistent with expected form high-redshift galaxy: clear blue continuum 1.5 to 4 microns complete dropout in F115W. The core is extremely compact imaging. analyze image two-component model, using point source and S\'{e}rsic profile that fits half-light radius 200 pc an index $n=0.9$....
Abstract JWST has revolutionized the field of extragalactic astronomy with its sensitive and high-resolution infrared view distant Universe. Adding to new legacy observations, we present first NIRCam imaging data release from Advanced Deep Extragalactic Survey (JADES), providing nine filters ∼25 arcmin 2 covering Hubble Ultra Field portions Great Observatories Origins South. Utilizing 87 on-sky dual-filter hours exposure time, these images reveal deepest ever near-infrared this iconic field....
ABSTRACT We present an interstellar medium and stellar population analysis of three spectroscopically confirmed z > 7 galaxies in the Early Release Observations JWST/NIRCam JWST/NIRSpec data SMACS J0723.3−7327 cluster. use Bayesian spectral energy distribution-fitting code prospector with a flexible star formation history (SFH), variable dust attenuation law, self-consistent model nebular emission (continuum lines). Importantly, we self-consistently fit both line fluxes from...
We present emission-line ratios from a sample of 27 Lyman-break galaxies z ∼ 5.5 − 9.5 with −17.0 < M 1500 −20.4, measured ultra-deep JWST/NIRSpec multi-object spectroscopy the JWST Advanced Deep Extragalactic Survey (JADES). used combination 28 h deep PRISM/CLEAR and 7 G 395 / F 290 LP observations to measure, or place strong constraints on, widely studied rest-frame optical emission lines including H α , β [O II ] λλ 3726, 3729, [Ne III λ 3869, 4959, 5007, I 6300, [N 6583, [S 6716, 6731...
Abstract We present JWST Extragalactic Medium-band Survey, the first public medium-band imaging survey carried out using JWST/NIRCam and NIRISS. These observations use ∼2 ∼4 μ m filters (NIRCam F182M, F210M, F430M, F460M, F480M; NIRISS F430M F480M in parallel) over 15.6 arcmin 2 Hubble Ultra Deep Field (UDF), thereby building on deepest multiwavelength data sets available anywhere sky. describe our science goals, design, NIRCam image reduction methods, release of science-ready mosaics, which...
We analysed the gas-phase metallicity properties of a sample low-stellar-mass (log M ⋆ / ⊙ ≲ 9) galaxies at 3 < z 10 observed with JWST/NIRSpec as part JADES programme in its deep GOODS-S tier. By combining this more massive similar redshifts from other programmes, we study scaling relations between stellar mass ( ), oxygen abundance (O/H), and star-formation rate (SFR) for 146 spanning three orders magnitude out to epoch early galaxy assembly. find evidence shallower slope low-mass end...
Abstract We present a catalog of 717 candidate galaxies at z > 8 selected from 125 square arcmin NIRCam imaging as part the JWST Advanced Deep Extragalactic Survey (JADES). combine full JADES data set with Medium and First Reionization Epoch Spectroscopic COmplete (FRESCO) along extremely deep existing observations Hubble Space Telescope (HST)/Advanced Camera for Surveys (ACS) final filter that includes 15 JWST/NIRCam filters five HST/ACS filters. The high-redshift galaxy candidates were...
The dramatic first images with James Webb Space Telescope (JWST) demonstrated its power to provide unprecedented spatial detail for galaxies in the high-redshift universe. Here, we leverage resolution and depth of JWST Cosmic Evolution Early Release Science Survey (CEERS) data Extended Groth Strip (EGS) perform pixel-level morphological classifications F150W imaging using Morpheus deep learning framework astronomical image analysis. By cross-referencing existing photometric redshift catalogs...
We present JADES JWST/NIRSpec spectroscopy of GN-z11, the most luminous candidate $z>10$ Lyman break galaxy in GOODS-North field with $M_{UV}=-21.5$. derive a redshift $z=10.603$ (lower than previous determinations) based on multiple emission lines our low and medium resolution spectra over $0.8-5.3 μ$m. significantly detect continuum measure blue rest-UV spectral slope $β=-2.4$. Remarkably, we see spatially-extended Lyman-$α$ (despite highly-neutral IGM expected at this early epoch),...
We present an overview of the James Webb Space Telescope (JWST) Advanced Deep Extragalactic Survey (JADES), ambitious program infrared imaging and spectroscopy in GOODS-S GOODS-N deep fields, designed to study galaxy evolution from high redshift cosmic noon. JADES uses about 770 hours Cycle 1 guaranteed time largely Near-Infrared Camera (NIRCam) Spectrograph (NIRSpec) instrument teams. In GOODS-S, around Hubble Ultra Field Chandra South, produces a region ~45 arcmin$^2$ with average 130 hrs...
Abstract Using deep JWST imaging from JADES, JEMS, and SMILES, we characterize optically faint extremely red galaxies at z > 3 that were previously missing galaxy census estimates. The data indicate the existence of abundant, dusty, poststarburst-like down to 10 8 M ⊙ , below sensitivity limit Spitzer Atacama Large Millimeter/submillimeter Array (ALMA). Modeling NIRCam Hubble Space Telescope (HST) photometry these sources can result in high values for both stellar mass star formation rate...
We present the properties of 17 faint Lyman- α emitting galaxies (LAEs) at z > 5.8 from JWST Advanced Deep Extragalactic Survey (JADES) spectroscopic data in Hubble Ultra Field/GOODS-S. These LAEs span a redshift range ≈ − 8.0 and UV magnitude M −17 to −20.6, with Ly equivalent width (EW) ≈25 350 Å. The detection other rest-optical emission lines spectra these enables determination accurate systemic redshifts velocity offsets, as well physical chemical composition their stars interstellar...
ABSTRACT Reionization is thought to be driven by faint star-forming galaxies, but characterizing this population has long remained very challenging. Here, we utilize deep nine-band JADES (JWST Advanced Deep Extragalactic Survey)/NIRCam (Near-Infrared Camera) imaging study the and ionizing properties of 756 $z\sim 6-9$ including hundreds ultraviolet (UV)-faint objects ($M_\mathrm{UV}\gt -18$). The faintest ($m\sim 30$) galaxies in our sample typically have stellar masses $M_\ast \sim...
Abstract We characterize the earliest galaxy population in JADES Origins Field, deepest imaging field observed with JWST. make use of ancillary Hubble Space Telescope optical images (five filters spanning 0.4–0.9 μ m) and novel JWST 14 0.8−5 m, including seven medium-band filters, reaching total exposure times up to 46 hr per filter. combine all our data at >2.3 m construct an ultradeep image, as deep ≈31.4 AB mag stack 30.3–31.0 (5 σ , r = 0.″1 circular aperture) individual filters....
Abstract We report the discovery of an extreme galaxy overdensity at z = 5.4 in GOODS-S field using James Webb Space Telescope (JWST)/NIRCam imaging from JADES and JEMS alongside JWST/NIRCam wide-field slitless spectroscopy FRESCO. identified potential members Hubble Telescope+JWST photometry spanning λ 0.4–5.0 μ m. These data provide accurate well-constrained photometric redshifts down to m ≈ 29–30 mag. subsequently confirmed N 81 galaxies 5.2 < 5.5 JWST over 3.9–5.0 through a targeted...
Abstract By combining the James Webb Space Telescope (JWST)/NIRCam JADES and CEERS extragalactic data sets, we have uncovered a sample of 21 T Y brown dwarf candidates at best-fit distances between 0.1 4.2 kpc. These sources were selected by targeting blue 1–2.5 μ m colors red 3–4.5 that arise from molecular absorption in atmospheres eff < 1300 K dwarfs. We fit these using multiple models substellar present resulting fluxes, sizes, effective temperatures, other derived properties for...
Abstract HDF850.1 is the brightest submillimeter galaxy (SMG) in Hubble Deep Field. It known as a heavily dust-obscured star-forming embedded an overdense environment at z = 5.18. With nine-band NIRCam images 0.8–5.0 μ m obtained through JWST Advanced Extragalactic Survey, we detect and resolve rest-frame UV–optical counterpart of HDF850.1, which splits into two components because heavy dust obscuration center. The southern component leaks UV H α photons, bringing ∼100 times above empirical...
Abstract We present the third data release of JWST Advanced Deep Extragalactic Survey (JADES), providing both imaging and spectroscopy in two GOODS fields. Spectroscopy consists medium-depth deep NIRSpec/microshutter assembly spectra 4000 targets, covering spectral range 0.6–5.3 μ m observed with low-dispersion prism ( R = 30–300) all three medium-resolution gratings 500–1500). describe observations, reduction, sample selection, target allocation. measured 2375 redshifts (2053 from multiple...
Abstract Cosmic reionization began when ultraviolet (UV) radiation produced in the first galaxies illuminating cold, neutral gas that filled primordial Universe 1,2 . Recent James Webb Space Telescope (JWST) observations have shown surprisingly UV-bright were place beyond redshift z = 14, was less than 300 Myr old 3–5 Smooth turnovers of their UV continua been interpreted as damping-wing absorption Lyman-α (Ly-α), principal hydrogen transition 6–9 However, spectral signatures encoding...