Justin Spilker
A5064669275- Galaxies: Formation, Evolution, Phenomena
- Astronomy and Astrophysical Research
- Astrophysics and Star Formation Studies
- Stellar, planetary, and galactic studies
- Gamma-ray bursts and supernovae
- Astrophysical Phenomena and Observations
- Astrophysics and Cosmic Phenomena
- Spectroscopy and Laser Applications
- Astronomical Observations and Instrumentation
- Adaptive optics and wavefront sensing
- Radio Astronomy Observations and Technology
- Cosmology and Gravitation Theories
- Scientific Research and Discoveries
- Phase Equilibria and Thermodynamics
- Astro and Planetary Science
- Pulsars and Gravitational Waves Research
- CCD and CMOS Imaging Sensors
- Pharmacological Effects and Assays
- Black Holes and Theoretical Physics
- Particle Accelerators and Free-Electron Lasers
- Laser Design and Applications
- Calibration and Measurement Techniques
- High-Energy Particle Collisions Research
- Superconducting and THz Device Technology
- Planetary Science and Exploration
Mitchell Institute
2021-2024
Texas A&M University
2021-2024
Goddard Space Flight Center
2023
University of California, Irvine
2023
California Institute of Technology
2023
University of California, Berkeley
2023
The University of Texas at Austin
2018-2022
University of Arizona
2013-2018
Using the Atacama Large Millimeter/submillimeter Array, we have conducted a blind redshift survey in 3 mm atmospheric transmission window for 26 strongly lensed dusty star-forming galaxies (DSFGs) selected with South Pole Telescope. The sources were to S1.4 > 20 mJy and dust-like spectrum and, remove low-z sources, not bright radio (S843 MHz < 6 mJy) or far-infrared counterparts (S100 μm 1 Jy, S60 200 mJy). We robustly detect 44 line features our survey, which identify as redshifted emission...
The South Pole Telescope has discovered one hundred gravitationally lensed, high-redshift, dusty, star-forming galaxies (DSFGs). We present 0.5" resolution 870um Atacama Large Millimeter/submillimeter Array imaging of a sample 47 DSFGs spanning z=1.9-5.7, and construct gravitational lens models these sources. Our visibility-based modeling incorporates several sources residual interferometric calibration uncertainty, allowing us to properly account for noise in the observations. At least 70%...
Using the Australia Telescope Compact Array (ATCA), we conducted a survey of CO J=1-0 and J=2-1 line emission towards strongly lensed high-redshift dusty star forming galaxies (DSFGs) previously discovered with South Pole (SPT). Our sample comprises 17 sources that had CO-based spectroscopic redshifts obtained Atacama Large Millimeter/submillimeter (ALMA) Pathfinder Experiment (APEX). We detect all known in either or J=2-1. Twelve are detected 7-mm continuum. The derived luminosities imply...
We present [CII] observations of 20 strongly lensed dusty star forming galaxies at 2.1 < z 5.7 using APEX and Herschel. The sources were selected on their 1.4 mm flux (S_1.4mm > mJy) from the South Pole Telescope survey, with far-infrared (FIR) luminosities determined extensive photometric data. line is robustly detected in 17 sources, all but one being spectrally resolved. Eleven out observed also have low-J CO detections ATCA. A comparison mid- high-J lines ALMA reveals consistent velocity...
We use the Atacama Large Millimeter/submillimeter Array (ALMA) in Cycle 1 to determine spectroscopic redshifts of high-redshift dusty star-forming galaxies (DSFGs) selected by their 1.4mm continuum emission South Pole Telescope (SPT) survey. present ALMA 3mm spectral scans between 84-114GHz for 15 and targeted 1mm observations an additional eight sources. Our yield 30 new line detections from CO, [CI] , [NII] H_2O NH_3. further APEX [CII] CO mid-J seven sources which only a single was...
We present a point source catalog from 771 square degrees of the South Pole Telescope Sunyaev Zel'dovich (SPT-SZ) survey at 95, 150, and 220 GHz. detect 1545 sources above 4.5 sigma significance in least one band. Based on their relative brightness between bands, we classify into two populations, dominated by synchrotron emission active galactic nuclei, thermal dust-enshrouded star-forming galaxies. find 1238 307 dusty sources. cross-match all against external catalogs 189 unidentified The...
We report the discovery and constrain physical conditions of interstellar medium highest-redshift millimeter-selected dusty star-forming galaxy (DSFG) to date, SPT-S J031132-5823.4 (hereafter SPT0311-58), at $z=6.900 +/- 0.002$. SPT0311-58 was discovered via its 1.4mm thermal dust continuum emission in South Pole Telescope (SPT)-SZ survey. The spectroscopic redshift determined through an ALMA 3mm frequency scan that detected CO(6-5), CO(7-6) [CI](2-1), subsequently confirmed by detections...
We present the average rest-frame spectrum of high-redshift dusty, star-forming galaxies from 250-770GHz. This was constructed by stacking ALMA 3mm spectra 22 such sources discovered South Pole Telescope and spanning z=2.0-5.7. In addition to multiple bright spectral features 12CO, [CI], H2O, we also detect several faint transitions 13CO, HCN, HNC, HCO+, CN, use observed line strengths characterize typical properties interstellar medium these starburst galaxies. find that 13CO brightness in...
Though half of cosmic starlight is absorbed by dust and reradiated at long wavelengths (3$μ$m-3mm), constraints on the infrared through millimeter galaxy luminosity function (the `IRLF') are poor in comparison to rest-frame ultraviolet optical function, particularly z>2.5. Here we present a backward evolution model for interpreting number counts, redshift distributions, cross-band flux density correlations submillimeter sky, from 70$μ$m-2mm, using IRLF out epoch reionization. Mock maps...
We present Atacama Large Millimeter Array [C i](1 − 0) (rest frequency 492 GHz) observations for a sample of 13 strongly lensed dusty star-forming galaxies (DSFGs) originally discovered at 1.4 mm in blank-field survey by the South Pole Telescope (SPT). compare these new data with available i] from literature, allowing study interstellar medium (ISM) properties ∼30 extreme DSFGs spanning redshift range 2 < z 5. Using line as tracer molecular ISM, we find mean gas mass SPT-DSFGs 6.6 × 1010 M⊙....
We report the serendipitous detection of two 3 mm continuum sources found in deep ALMA Band observations to study intermediate redshift galaxies COSMOS field. One is near a foreground galaxy at 1.3", but previously unknown dust-obscured star-forming (DSFG) probable $z_{CO}=3.329$, illustrating risk misidentifying shorter wavelength counterparts. The optical-to-mm spectral energy distribution (SED) favors grey $\lambda^{-0.4}$ attenuation curve and results significantly larger stellar mass...
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...
The 2mm Mapping Obscuration to Reionization with ALMA (MORA) Survey was designed detect high redshift ($z\gtrsim4$), massive, dusty star-forming galaxies (DSFGs). Here we present two, likely sources, identified in the survey whose physical characteristics are consistent a class of optical/near-infrared (OIR) invisible DSFGs found elsewhere literature. We first perform rigorous analysis all available photometric data fit spectral energy distributions and estimate redshifts before deriving...
Abstract Accurate models of the star formation histories (SFHs) recently quenched galaxies can provide constraints on when and how shut down their formation. The recent development nonparametric SFH promises flexibility required to make these measurements. However, model prior choices significantly affect derived SFHs, particularly for post-starburst (PSBs), which have sharp changes in SFH. In this paper, we create mock PSBs, then use Prospector SED fitting software test well four different...
Abstract We have observed the z = 4.3 protocluster SPT2349−56 with Australia Telescope Compact Array (ATCA) aim of detecting radio-loud active galactic nuclei (AGNs) among ∼30 submillimeter (submm) galaxies (SMGs) identified in structure. detect central complex submm sources at 2.2 GHz a luminosity L (4.42 ± 0.56) × 10 25 W Hz −1 . MeerKAT and Australian Square Kilometre Pathfinder also source 816 MHz 888 MHz, respectively, constraining radio spectral index to α −1.45 0.16, implying 1.4,rest...
Massive star-forming galaxies in the high-redshift universe host large reservoirs of cold gas their circumgalactic medium (CGM). Traditionally, these have been linked to diffuse H I Lyman- α (Ly ) emission extending beyond ≈10 kpc scales. In recent years, millimeter and submillimeter observations started identify even colder CGM through molecular and/or atomic tracers such as [C II ] 158 μm transition. this context, we studied well-known J1000+0234 system at z = 4.54 that hosts a massive...
We present Atacama Large Millimeter/submillimeter Array (ALMA) 860 micrometer imaging of four high-redshift (z=2.8-5.7) dusty sources that were detected using the South Pole Telescope (SPT) at 1.4 mm and are not seen in existing radio to far-infrared catalogs. At 1.5 arcsec resolution, ALMA data reveal multiple images each submillimeter source, separated by 1-3 arcsec, consistent with strong lensing intervening galaxies visible near-IR these sources. describe a gravitational lens modeling...
Galaxies grow inefficiently, with only a few percent of the available gas converted into stars each free-fall time. Feedback processes, such as outflowing winds driven by radiation pressure, supernovae or supermassive black hole accretion, can act to halt star formation if they heat expel supply. We report molecular outflow launched from dust-rich star-forming galaxy at redshift 5.3, one billion years after Big Bang. The reaches velocities up 800 km/s relative galaxy, is resolved multiple...
The Galactic Center black hole Sagittarius A* (Sgr A*) is a prime observing target for the Event Horizon Telescope (EHT), which can resolve 1.3 mm emission from this source on angular scales comparable to that of general relativistic shadow. Previous EHT observations have used visibility amplitudes infer morphology millimeter-wavelength emission. Potentially much richer information contained in phases. We report phase Sgr obtained with total 13 nights over 4 years. Closure phases, sum phases...
Abstract We report results from very long baseline interferometric (VLBI) observations of the supermassive black hole in Galactic center, Sgr A*, at 1.3 mm (230 GHz). The were performed 2013 March using six VLBI stations Hawaii, California, Arizona, and Chile. Compared to earlier observations, addition APEX telescope Chile almost doubles longest length array, provides additional uv coverage N–S direction, leads a spatial resolution ∼30 μ as (∼3 Schwarzschild radii) for A*. source is detected...