Kelly A. Douglass
A5002619785- Galaxies: Formation, Evolution, Phenomena
- Astronomy and Astrophysical Research
- Stellar, planetary, and galactic studies
- Gamma-ray bursts and supernovae
- Astronomical Observations and Instrumentation
- Cosmology and Gravitation Theories
- Dark Matter and Cosmic Phenomena
- Particle Accelerators and Free-Electron Lasers
- Astrophysics and Star Formation Studies
- Remote Sensing in Agriculture
- Astrophysics and Cosmic Phenomena
- Geophysics and Gravity Measurements
- CCD and CMOS Imaging Sensors
- Impact of Light on Environment and Health
- American and British Literature Analysis
- Data Visualization and Analytics
- Solar and Space Plasma Dynamics
- Lichen and fungal ecology
- Latin American and Latino Studies
- Anomaly Detection Techniques and Applications
- American Literature and Culture
- Computational Physics and Python Applications
- Scientific Research and Discoveries
- Atmospheric Ozone and Climate
- Black Holes and Theoretical Physics
University of Rochester
2019-2024
Astronomy and Space
2023
Drexel University
2017-2018
The Dark Energy Spectroscopic Instrument (DESI) has embarked on an ambitious five-year survey to explore the nature of dark energy with spectroscopy 40 million galaxies and quasars. DESI will determine precise redshifts employ Baryon Acoustic Oscillation method measure distances from nearby universe z > 3.5, as well growth structure probe potential modifications general relativity. In this paper we describe significant instrumentation developed for survey. new includes a wide-field, 3.2-deg...
The Dark Energy Spectroscopic Instrument (DESI) was designed to conduct a survey covering 14,000 deg$^2$ over five years constrain the cosmic expansion history through precise measurements of Baryon Acoustic Oscillations (BAO). scientific program for DESI evaluated during month Survey Validation (SV) campaign before beginning full operations. This produced deep spectra tens thousands objects from each stellar (MWS), bright galaxy (BGS), luminous red (LRG), emission line (ELG), and quasar...
Abstract The Dark Energy Spectroscopic Instrument (DESI) completed its 5 month Survey Validation in 2021 May. Spectra of stellar and extragalactic targets from constitute the first major data sample DESI survey. This paper describes public release those spectra, catalogs derived properties, intermediate products. In total, includes good-quality spectral information 466,447 objects targeted as part Milky Way Survey, 428,758 Bright Galaxy 227,318 Luminous Red sample, 437,664 Emission Line...
Abstract The Dark Energy Spectroscopic Instrument (DESI) Survey has obtained a set of spectroscopic measurements galaxies to validate the final survey design and target selections. To assist in these tasks, we visually inspect DESI spectra approximately 2500 bright galaxies, 3500 luminous red (LRGs), 10,000 emission-line (ELGs) obtain robust redshift identifications. We then utilize inspected information characterize performance operation. Based on visual inspection (VI) catalogs, our...
The Dark Energy Spectroscopic Instrument (DESI) was designed to conduct a survey covering 14,000 deg$^2$ over five years constrain the cosmic expansion history through precise measurements of Baryon Acoustic Oscillations (BAO). scientific program for DESI evaluated during month Survey Validation (SV) campaign before beginning full operations. This produced deep spectra tens thousands objects from each stellar (MWS), bright galaxy (BGS), luminous red (LRG), emission line (ELG), and quasar...
Inflation may provide unique insight into the physics at highest available energy scales that cannot be replicated in any realistic terrestrial experiment. Features primordial power spectrum are generically predicted a wide class of models inflation and its alternatives, observationally one most overlooked channels for finding evidence non-minimal inflationary models. Constraints from observations cosmic microwave background cover widest range feature frequencies, but sensitive constraints...
We describe the target selection and characteristics of DESI Peculiar Velocity Survey, largest survey peculiar velocities (PVs) using both fundamental plane (FP) Tully-Fisher (TF) relationship planned to date. detail how we identify suitable early-type galaxies (ETGs) for FP late-type (LTGs) TF relation photometric data provided by Legacy Imaging Survey DR9. Subsequently, provide targets 373 533 ETGs 118 637 LTGs within 5-year footprint. validate these selections existing morphological...
Abstract We produce several public void catalogs using a volume-limited subsample of the Sloan Digital Sky Survey Data Release 7 (SDSS DR7). Using new implementations three different void-finding algorithms, VoidFinder and two ZOBOV-based algorithms (VIDE REVOLVER), we identify 1163, 531, 518 cosmic voids with radii >10 h −1 Mpc, respectively, out to redshift z = 0.114 assuming Planck 2018 cosmology, 1184, 535, 519 WMAP5 cosmology. compute effective centers for all find none an radius...
Abstract We present three separate void catalogs created using a volume-limited sample of the DESI Data Release 1 Bright Galaxy Survey. use algorithms VoidFinder and V 2 to construct out redshift z = 0.24. Excluding voids affected by boundaries survey, we obtain 1489 with VoidFinder, 389 REVOLVER pruning, 297 VIDE pruning. Comparing our overlapping Sloan Digital Sky Survey catalogs, find generally consistent properties but significant differences in volume overlap, which attribute galaxy...
Abstract We present the Multi-Object Spectroscopy of Transient (MOST) Hosts survey. The survey is planned to run throughout 5 yr operation Dark Energy Spectroscopic Instrument (DESI) and will generate a spectroscopic catalog hosts most transients observed date, in particular all supernovae by public, untargeted, wide-field, optical surveys (Palomar Factory, PTF/intermediate PTF, Sloan Digital Sky Survey II, Zwicky Facility, DECAT, DESIRT). Science cases for MOST include Type Ia supernova...
The expansion of the Universe is understood to have accelerated during two epochs: in its very first moments a period Inflation and much more recently, at $z < 1$, when Dark Energy hypothesized drive cosmic acceleration. undiscovered mechanisms behind these epochs represent some most important open problems fundamental physics. large cosmological volume $2 z 5$, together with ability efficiently target high-$z$ galaxies known techniques, enables gains study Energy. A future spectroscopic...
We present the MOST Hosts survey (Multi-Object Spectroscopy of Transient Hosts). The is planned to run throughout five years operation Dark Energy Spectroscopic Instrument (DESI) and will generate a spectroscopic catalog hosts most transients observed date, in particular all supernovae by public, untargeted, wide-field, optical surveys (PTF/iPTF, SDSS II, ZTF, DECAT, DESIRT). Scientific questions for which be useful include Type Ia supernova cosmology, fundamental plane peculiar velocity...
Abstract We present a study of the ratio visible mass to total in spiral galaxies better understand relative amount dark matter different masses and evolutionary stages. Using velocities H α emission line measured spectroscopic observations from Sloan Digital Sky Survey (SDSS) MaNGA Data Release 17 (DR 17), we evaluate rotational velocity over 5500 disk at their 90% elliptical Petrosian radii, R 90 . compare this expected mass, which compute stellar, i , 2 heavy metals dust masses....
The Dark Energy Spectroscopic Instrument (DESI) Peculiar Velocity Survey aims to measure the peculiar velocities of early and late type galaxies within DESI footprint using both Fundamental Plane Tully-Fisher relations. Direct measurements can significantly improve constraints on growth rate structure, reducing uncertainty by a factor approximately 2.5 at redshift 0.1 compared Bright Galaxy Survey's space distortion alone. We assess quality stellar velocity dispersion from spectroscopic...
Abstract We explore how the definition of a void influences conclusions drawn about impact environment on galactic properties using two void-finding algorithms in Void Analysis Software Toolkit: Voronoi Voids ( V 2 ), Python implementation ZOnes Bordering On Voidness ZOBOV ); and VoidFinder , an algorithm that grows merges spherical regions. Using Sloan Digital Sky Survey Data Release 7, we find galaxies found voids tend to be bluer fainter have higher (specific) star formation rates than...
Voids are expansive regions in the universe containing significantly fewer galaxies than surrounding galaxy clusters and filaments.They a fundamental feature of cosmic web provide important information about physics cosmology.For example, correlations between voids luminous tracers large-scale structure improve constraints on expansion as compared to using alone, numerous studies have shown that void environment influences evolution galaxies.However, what constitutes is vague formulating...
Abstract We study how the void environment affects formation and evolution of galaxies in universe by comparing ratio dark matter halo mass to stellar voids with denser regions. Using spectroscopic observations from Sloan Digital Sky Survey MaNGA DR15, we estimate 641 937 use relative velocities H α emission line across galaxy’s surface measure rotation curve each galaxy because kinematics interstellar medium is smoother than kinematics. find that neither stellar-to-halo-mass relation nor...
We study how the cosmic environment affects galaxy evolution in Universe by comparing metallicities of dwarf galaxies voids with more dense regions. Ratios fluxes emission lines, particularly those forbidden [O III] and [S II] transitions, provide estimates a region's electron temperature number density. From these two quantities line 3727, 4363, 4959,5007, we estimate abundance oxygen Direct Te method. metallicity 42 blue, star-forming void 89 regions using spectroscopic observations from...
Abstract We study how the void environment affects chemical evolution of galaxies in universe by comparing oxygen and nitrogen abundances dwarf voids with denser regions. Using spectroscopic observations from Sloan Digital Sky Survey Data Release 7, we estimate oxygen, nitrogen, neon 889 672 use Direct T e method for calculating gas-phase because it is best suited low-metallicity, low-mass (dwarf) galaxies. A substitute [O ii ] λ 3727 doublet developed, permitting abundance estimates SDSS at...
Opening up a new window of millimeter-wave observations that span frequency bands in the range 30 to 500 GHz, survey half sky, and are both an order magnitude deeper (about 0.5 uK-arcmin) higher-resolution 10 arcseconds) than currently funded surveys would yield enormous gain understanding fundamental physics astrophysics. In particular, such allow for major advances measuring distribution dark matter gas on small-scales, needed insight 1.) particle properties, 2.) evolution galaxies, 3.)...
Abstract We study how well void-finding algorithms identify cosmic void regions and whether we can quantitatively qualitatively compare the voids they find with dynamical information from underlying matter distribution. Using ORIGAMI algorithm to determine number of dimensions along which dark particles have undergone shell crossing (crossing number) in N -body simulations AbacusSummit simulation suite, that no as belonging voids. then corresponding halo distribution using two different...
Using spectroscopic observations from the SDSS MaNGA DR15, we study relationships between ratio of total to visible mass and various parameters characterizing evolution environment galaxies in this survey. Measuring rotation curve with relative velocities H-alpha emission line across galaxy's surface, estimate each mass. We develop a statistical model describe observed distribution mass, which extract most probable value for ratio. present several characteristics describing galactic...
We explore how the definition of a void influences conclusions drawn about impact environment on galactic properties using two void-finding algorithms in Void Analysis Software Toolkit: V2, Python implementation ZOBOV, and VoidFinder, an algorithm which grows merges spherical regions. Using Sloan Digital Sky Survey Data Release 7, we find that galaxies found VoidFinder voids tend to be bluer, fainter, have higher (specific) star formation rates than denser Conversely, V2 show no significant...
We present three separate void catalogs created using a volume-limited sample of the DESI Year 1 Bright Galaxy Survey. use algorithms VoidFinder and V2 to construct out redshift z=0.24. obtain 1,461 interior voids with VoidFinder, 420 REVOLVER pruning, 295 VIDE pruning. Comparing our catalog an overlapping SDSS catalog, we find generally consistent properties but significant differences in volume overlap, which attribute galaxy selection survey masks. These are suitable for studying...
Abstract We examine how the cosmic environment affects chemical evolution of galaxies in universe by comparing N/O ratio dwarf voids with that denser regions. Ratios forbidden [O iii ] and [S ii transitions provide estimates a region’s electron temperature number density. estimate abundances oxygen nitrogen using these density emission-line fluxes <?CDATA $\lambda 3727$?> , \lambda 4959,5007$?> [N 6548,6584$?> direct T e method. Using spectroscopic observations from Sloan Digital Sky Survey...