John R. Weaver
A5048287383- Astronomy and Astrophysical Research
- Galaxies: Formation, Evolution, Phenomena
- Stellar, planetary, and galactic studies
- Gamma-ray bursts and supernovae
- Astrophysics and Star Formation Studies
- Adaptive optics and wavefront sensing
- Astrophysical Phenomena and Observations
- Astronomical Observations and Instrumentation
- CCD and CMOS Imaging Sensors
- Calibration and Measurement Techniques
- Remote Sensing in Agriculture
- Geophysics and Gravity Measurements
- Advanced Vision and Imaging
- Astrophysics and Cosmic Phenomena
- Scientific Research and Discoveries
- Radio Astronomy Observations and Technology
- Pulsars and Gravitational Waves Research
- Photocathodes and Microchannel Plates
- History and Developments in Astronomy
- Advanced Fluorescence Microscopy Techniques
- Spectroscopy and Laser Applications
- Particle Accelerators and Free-Electron Lasers
- Cosmology and Gravitation Theories
- Advanced Optical Sensing Technologies
- Meteorological Phenomena and Simulations
University of Massachusetts Amherst
2022-2024
University of Copenhagen
2020-2023
ASTRO-3D
2023
University of St Andrews
2018-2022
DAWN Center for Independent Living
2020-2022
American Society for Radiation Oncology
2022
Max Planck Institute for Astronomy
2018
Aptiv (United States)
2005
Abstract The first few 100 Myr at z > 10 mark the last major uncharted epoch in history of universe, where only a single galaxy (GN-z11 ≈ 11) is currently spectroscopically confirmed. Here we present search for luminous galaxies with JWST/NIRCam photometry spanning ≈1–5 μ m and covering 49 arcmin 2 from public JWST Early Release Science programs (CEERS GLASS). Our most secure candidates are two M UV −21 systems: GLASS-z12 GLASS-z10. These display abrupt ≳1.8 mag breaks their spectral...
Abstract The Cosmic Evolution Survey (COSMOS) has become a cornerstone of extragalactic astronomy. Since the last public catalog in 2015, wealth new imaging and spectroscopic data have been collected COSMOS field. This paper describes collection, processing, analysis these to produce reference photometric redshift catalog. Source detection multiwavelength photometry are performed for 1.7 million sources across 2 deg field, ∼966,000 which measured with all available broadband using both...
Abstract We present the survey design, implementation, and outlook for COSMOS-Web, a 255 hr treasury program conducted by James Webb Space Telescope in its first cycle of observations. COSMOS-Web is contiguous 0.54 deg 2 NIRCam imaging four filters (F115W, F150W, F277W, F444W) that will reach 5 σ point-source depths ranging ∼27.5–28.2 mag. In parallel, we obtain 0.19 MIRI one filter (F770W) reaching ∼25.3–26.0 build on rich heritage multiwavelength observations data products available COSMOS...
Abstract The James Webb Space Telescope is revealing a new population of dust-reddened broad-line active galactic nuclei (AGN) at redshifts z ≳ 5. Here we present deep NIRSpec/Prism spectroscopy from the Cycle 1 Treasury program Ultradeep NIRSpec and NIRCam ObserVations before Epoch Reionization (UNCOVER) 15 AGN candidates selected to be compact, with red continua in rest-frame optical but blue slopes UV. From photometry alone, they could have been dominated by dusty star formation or an...
Abstract The James Webb Space Telescope is now detecting early black holes (BHs) as they transition from “seeds” to supermassive BHs. Recently, Bogdan et al. reported the detection of an X-ray luminous BH, UHZ-1, with a photometric redshift at z > 10. Such extreme source this very high provides new insights on seeding and growth models for BHs given short time available formation growth. Harnessing exquisite sensitivity JWST/NIRSpec, here we report spectroscopic confirmation UHZ-1 =...
Context. How galaxies form, assemble, and cease their star formation is a central question within the modern landscape of galaxy evolution studies. These processes are indelibly imprinted on stellar mass function (SMF), its measurement understanding key to uncovering unified theory evolution. Aims. We present constraints shape SMF, quiescent fraction, cosmic density across 90% history Universe from z = 7.5 → 0.2 as means study physical that underpin Methods. The COSMOS survey an ideal...
Abstract Deep observations with the James Webb Space Telescope (JWST) have revealed an emerging population of red pointlike sources that could provide a link between postulated supermassive black hole seeds and observed quasars. In this work, we present JWST/NIRSpec spectrum from JWST Cycle 1 UNCOVER Treasury survey massive accreting at z = 8.50 displaying clear broad-line component as inferred H β line FWHM 3439 ± 413 km s −1 , typical region active galactic nucleus (AGN). The AGN nature...
We present the results of a systematic search for candidate quiescent galaxies in distant Universe eleven $JWST$ fields with publicly available observations collected during first three months operations and covering an effective sky area $\sim145$ arcmin$^2$. homogeneously reduce new data combine them existing from $Hubble\,Space\,Telescope$. select robust sample $\sim80$ quenching at $3 < z 5$ using two methods: (1) based on their rest-frame $UVJ$ colors, (2) novel quantitative approach...
We present the results of a search for high-redshift ($z>9$) galaxy candidates in JWST UNCOVER survey, using deep NIRCam and NIRISS imaging 7 bands over $\sim45$ arcmin$^2$ ancillary HST observations. The observations reach $5-\sigma$ limiting magnitude $\sim 29.2$ AB. identification high$-z$ relies on combination dropout selection photometric redshifts. find 16 at $9<z<12$ 3 $12<z<13$, eight are deemed very robust. Their lensing amplification ranges from $\mu=1.2$ to 11.5. Candidates have...
With just a month of data, JWST is already transforming our view the Universe, revealing and resolving starlight in unprecedented populations galaxies. Although ``HST-dark" galaxies have previously been detected at long wavelengths, these observations generally suffer from lack spatial resolution which limits ability to characterize their sizes morphologies. Here we report on first subset HST-dark population that are bright with JWST/NIRCam (4.4$\mu$m<24.5mag) very faint or even invisible...
ABSTRACT We present a new parametric lens model for the massive galaxy cluster Abell 2744 based on ultra-deep JWST imaging taken in framework of UNCOVER program. These observations constitute deepest images lensing to date, adding existing deep Hubble Space Telescope (HST) and recent Early Release Science Director’s Discretionary Time data this field. The wide field view (∼45 arcmin2) extends beyond cluster’s well-studied central core reveals spectacular wealth prominent lensed features...
Abstract Recent JWST/NIRCam imaging taken for the ultra-deep UNCOVER program reveals a very red dropout object at z phot ≃ 7.6, triply imaged by galaxy cluster A2744 ( d = 0.308). All three images are compact, i.e., unresolved, with delensed size upper limit of r e ≲ 35 pc. The have apparent magnitudes m F444W ∼ 25−26 AB, and magnification-corrected absolute UV magnitude source is M UV,1450 −16.81 ± 0.09. From sum observed fluxes from spectral energy distribution (SED) analysis, we obtain...
Abstract In 2022 November, the James Webb Space Telescope (JWST) returned deep near-infrared images of A2744—a powerful lensing cluster capable magnifying distant, incipient galaxies beyond it. Together with existing Hubble (HST) imaging, this publicly available data set opens a fundamentally new discovery space to understand remaining mysteries formation and evolution across cosmic time. work, we detect measure some 60,000 objects 49 arcmin 2 JWST footprint down 5 σ limiting magnitude ∼30...
Abstract We report the discovery of 15 exceptionally luminous 10 ≲ z 14 candidate galaxies discovered in first 0.28 deg 2 JWST/NIRCam imaging from COSMOS-Web survey. These sources span rest-frame UV magnitudes −20.5 > M −22, and thus constitute most intrinsically ≳ candidates identified by JWST to date. Selected via NIRCam imaging, deep ground-based observations corroborate their detection help significantly constrain photometric redshifts. analyze spectral energy distributions using...
Abstract The era of the James Webb Space Telescope ushers stellar population models into uncharted territories, particularly at high-redshift frontier. In a companion paper, we apply Prospector Bayesian framework to jointly infer galaxy redshifts and properties from broadband photometry as part UNCOVER survey. Here present comprehensive error budget in spectral energy distribution (SED) modeling. Using sample selected have photometric higher than 9, quantify systematic shifts stemming...
Abstract We report JWST/NIRSpec spectra of three distant T-type brown dwarfs identified in the Ultradeep NIRSpec and NIRCam ObserVations before Epoch Reionization (UNCOVER) survey Abell 2744 lensing field. One source was previously reported as a candidate T dwarf on basis photometry, while two sources were initially active galactic nuclei. Low-resolution 1–5 μ m confirm presence molecular features consistent with atmospheres, comparison to spectral standards infers classifications sdT1, T6,...
Abstract In this paper we describe the survey design for Ultradeep NIRSpec and NIRCam Observations before Epoch of Reionization (UNCOVER) Cycle 1 JWST Treasury program, which executed its early imaging component in 2022 November. The UNCOVER includes ultradeep (∼29–30AB) ∼45 arcmin 2 on around well-studied A2744 galaxy cluster at z = 0.308 will follow up ∼500 galaxies with extremely deep low-resolution spectroscopy NIRSpec/PRISM during summer 2023, repeat visits 2024. We science goals,...
Abstract We present the results of a systematic study rest-frame optical morphology quiescent galaxies at z ≥ 3 using Near-Infrared Camera (NIRCam) on board James Webb Space Telescope (JWST). Based sample selected by UVJ color or NUVUVJ color, we focus 26 with <?CDATA $9.8\lt \mathrm{log}({M}_{\star }/{M}_{\odot })\lt 11.4$?> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mn>9.8</mml:mn> <mml:mo><</mml:mo> <mml:mi>log</mml:mi> <mml:mo...
ABSTRACT Combining the public JWST/NIRCam imaging programs CEERS, PRIMER, and JADES, spanning a total area of $\sim 500\, {\rm arcmin}^2$, we obtain sample $\gt $30 000 galaxies at $z_{\rm phot}\sim 4\!-\!9$ that allows us to perform complete, rest-optical-selected census galaxy population $z\gt 3$. Comparing stellar mass $M_*$ UV-slope $\beta$ distributions between JWST- HST-selected samples, generally find very good agreement no significant biases. Nevertheless, JWST enables probe new...
will provide deep near-infrared (NIR) imaging to ∼26.5 AB magnitude over ∼59 deg^2 in its and auxiliary fields. The Cosmic DAWN survey combines dedicated archival UV--NIR observations matched depth multiwavelength of the consistently measured NIR-selected photometric catalogues, accurate redshifts, measurements galaxy properties a redshift z∼ 10. catalogues include Spitzer IRAC data that are critical for stellar mass at z ≳ 2.5 high-z science. These complement standard which not data. In...
Abstract We study of the role galaxy–galaxy interactions and disk instabilities in producing starburst activity galaxies out to z = 4. For this, we use a sample 387 with robust total star formation rate measurements from Herschel, gas masses Atacama Large Millimeter/submillimeter Array, stellar redshifts multiband photometry, JWST/NIRCam rest-frame optical imaging. Using mass-controlled samples, find an increased fraction interacting regime at all This increase correlates efficiency (SFE)...
The Beyond Ultra-deep Frontier Fields and Legacy Observations (BUFFALO) is a 101 orbit + parallel Cycle 25 Hubble Space Telescope Treasury program taking data from 2018-2020. BUFFALO will expand existing coverage of the (HFF) in WFC3/IR F105W, F125W, F160W ACS/WFC F606W F814W around each six HFF clusters flanking fields. This additional area has not been observed by HST but already covered deep multi-wavelength datasets, including Spitzer Chandra. As with original program, designed to take...
Abstract We present the characteristics of 2 mm selected sources from largest Atacama Large Millimeter/submillimeter Array (ALMA) blank-field contiguous survey conducted to date, Mapping Obscuration Reionization with ALMA (MORA) covering 184 arcmin at mm. Twelve 13 detections above 5 σ are attributed emission galaxies, 11 which dominated by cold dust emission. These have a median redshift <?CDATA $\langle {z}_{2\,\mathrm{mm}}\rangle ={3.6}_{-0.3}^{+0.4}$?> <mml:math...