A5052024712- Astronomy and Astrophysical Research
- Stellar, planetary, and galactic studies
- Galaxies: Formation, Evolution, Phenomena
- Astrophysics and Star Formation Studies
- Adaptive optics and wavefront sensing
- Gamma-ray bursts and supernovae
- Astronomical Observations and Instrumentation
- Astrophysical Phenomena and Observations
- Astrophysics and Cosmic Phenomena
- Spacecraft and Cryogenic Technologies
- Radio Astronomy Observations and Technology
- Calibration and Measurement Techniques
- CCD and CMOS Imaging Sensors
- Astro and Planetary Science
- Spacecraft Design and Technology
- History and Developments in Astronomy
- Pulsars and Gravitational Waves Research
- Scientific Research and Discoveries
- Spectroscopy and Laser Applications
- Cardiac and Coronary Surgery Techniques
- Atherosclerosis and Cardiovascular Diseases
- Adipokines, Inflammation, and Metabolic Diseases
- Advanced Thermodynamic Systems and Engines
- Remote Sensing in Agriculture
- Superconducting and THz Device Technology
California Institute of Technology
2014-2024
Infrared Processing and Analysis Center
2018-2024
Institut für Palliative Care
2022
Fleet Science Center
2009-2015
Space Telescope Science Institute
2001-2003
University of Kentucky
2000-2002
University of Hertfordshire
1997-2001
Tampere University
2001
Tampere University Hospital
2001
University of Florida
1995-1998
The Infrared Array Camera (IRAC) is one of three focal plane instruments in the Spitzer Space Telescope. IRAC a four-channel camera that obtains simultaneous broad-band images at 3.6, 4.5, 5.8, and 8.0 microns. Two nearly adjacent 5.2x5.2 arcmin fields view are viewed by four channels pairs (3.6 5.8 microns; 4.5 8 microns). All detector arrays 256x256 pixels size, with two shorter wavelength using InSb longer Si:As IBC detectors. powerful survey instrument because its high sensitivity, large...
The Spitzer Survey of Stellar Structure in Galaxies (S^4G) is a deep 3.6 and 4.5 μm imaging survey 2352 nearby (<40 Mpc) galaxies. We describe the S(^4)G data analysis pipeline 4, which dedicated to two-dimensional structural surface brightness decompositions images, using GALFIT3.0. Besides automatic 1-component Sersic fits, 2-component bulge + exponential disk we present human-supervised multi-component decompositions, include, when judged appropriate, central point source, bulge, disk,...
We present new Hubble Space Telescope I-band images of a sample 77 nearby late-type spiral galaxies with low inclination. The main purpose this catalog is to study the frequency and properties nuclear star clusters. In 59 our sample, we have identified distinct, compact (but resolved), dominant source at or very close photocenter. many cases, these clusters are only prominent within few kiloparsecs from galaxy nucleus. surface brightness profiles, derived elliptical isophote fits, all for...
We analyze the observed properties of nested and single stellar bar systems in disk galaxies. The 112 galaxies our sample comprise largest matched Seyfert vs. non-Seyfert nearby with complete near-infrared or optical imaging sensitive to lengthscales ranging from tens pc kpc. find that a significant fraction galaxies, 17% +/- 4%, has more than one bar, 28% 5% barred have bars. fractions appear be stable according reasonable changes adopted criteria. For these bars, we detect clear division...
One-third of present-day spirals host optically visible strong bars that drive their dynamical evolution. However, the fundamental question how evolve over cosmological times has yet to be resolved, and even frequency at intermediate redshifts remains controversial. We investigate out z ~ 1 drawing on a sample 1590 galaxies from Galaxy Evolution Morphologies SEDs survey, which provides morphologies Hubble Space Telescope Advanced Camera for Surveys (ACS) two-band images accurate COMBO-17...
The Spitzer Survey of Stellar Structure in Galaxies is a volume, magnitude, and size-limited survey 2352 nearby galaxies with deep imaging at 3.6 4.5 μm.In this paper, we describe our surface photometry pipeline showcase the associated data products that have released to community.We also identify physical mechanisms leading different levels central stellar mass concentration for same total mass.Finally, derive local mass-size relation μm morphologies.Our radial profiles reach densities...
ABSTRACT We examine the repeatability, reliability, and accuracy of differential exoplanet eclipse depth measurements made using InfraRed Array Camera (IRAC) on Spitzer Space Telescope during post-cryogenic mission. have re-analyzed an existing 4.5 μ m data set, consisting 10 observations XO-3b system secondary eclipse, seven different techniques for removing correlated noise. find that, average, a given technique, estimate is repeatable from epoch to within 156 parts per million (ppm). Most...
We used the Hubble Space Telescope Wide Field Planetary Camera 2 to obtain I-band images of centers 81 brightest cluster galaxies (BCGs), drawn from a volume-limited sample nearby BCGs. The show rich variety morphological features, including multiple or double nuclei, dust, stellar disks, point-source and central surface brightness depressions. High-resolution profiles could be inferred for 60 galaxies. Of those, 88% have well-resolved cores. relationship between core size galaxy luminosity...
We present 70 and 160 μm observations from the Spitzer extragalactic First Look Survey (xFLS). The data reduction techniques methods for producing co-added mosaics source catalogs are discussed. Currently, 26% of sample 49% μm–selected sources have redshifts. majority with redshifts star-forming galaxies at z < 0.5, while about 5% infrared colors consistent active galactic nuclei. observed agree spectral energy distributions (SEDs) local previously determined IRAS Infrared Space Observatory...
By combining the 0.12 deg2 F814W Hubble Space Telescope (HST) and Spitzer MIPS 24 μm imaging in First Look Survey (FLS), we investigate properties of interacting merging mid-infrared bright faint sources at 0.2 ≤ z 1.3. We find a marginally significant increase pair fraction for detected, optically selected close pairs, with 0.25 ± 0.10 ~ 1, contrast to 0.11 0.08 0.4, while galaxies below our detection limit show consistent zero all redshifts. In addition, detected fluxes ≥0.1 mJy are on...
Binary black hole (BH) central engine description for the unique blazar OJ 287 predicted that next secondary BH impact-induced bremsstrahlung flare should peak on 2019 July 31. This prediction was based detailed general relativistic modeling of trajectory around primary and its accretion disk. The expected termed Eddington to commemorate centennial celebrations now-famous solar eclipse observations test relativity by Sir Arthur Eddington. We analyze multi-epoch Spitzer between 31 September...
Context. Mergers and tidal interactions between massive galaxies their dwarf satellites are a fundamental prediction of the Lambda-cold dark matter cosmology. These events thought to provide important observational diagnostics non-linear structure formation. Stellar streams in Milky Way Andromeda spectacular evidence for ongoing satellite disruption. However, constructing statistically meaningful sample beyond Local Group has proven daunting challenge, full potential deepening our...
The detectors in the Mid-Infrared Instrument (MIRI) of James Webb Space Telescope (JWST) are arsenic-21 doped silicon impurity band conduction (Si:As IBC) devices and direct descendants Spitzer IRAC22 long wavelength arrays (channels 3 4). With appropriate data processing, they can provide excellent per-23 formance. In this paper we discuss various non-ideal behaviors these that need to be addressed24 realize their potential. We have developed a set algorithms toward goal, building on...
We present Infrared Array Camera (IRAC) data and source catalogs from the Spitzer Space Telescope Extragalactic First Look Survey. The were taken in four broad bands centered at nominal wavelengths of 3.6, 4.5, 5.8, 8.0 μm. A set mosaics have been produced that are ≈80% complete ≈99% reliable to their chosen flux density limits. main field survey covers 3.8 deg2 has limits 20, 25, 100, 100 μJy μm, respectively. deeper "verification" 0.25 with 10, 30, 30 μJy, also include deep ELAIS-N1 field,...
The Infrared Array Camera (IRAC) on the <i>Spitzer</i> Space Telescope has been used to measure < 10<sup>-4</sup> temporal variations in point sources (such as transiting extrasolar planets) at 3.6 and 4.5 μm. Due under-sampled nature of PSF, warm IRAC arrays show much 8% sensitivity center PSF moves across a pixel due normal spacecraft pointing wobble drift. These intra-pixel gain are largest source correlated noise photometry. Usually this effect is removed by fitting model science...
Abstract We present observational constraints on the stellar populations of two ultra-diffuse galaxies (UDGs) using optical through near-infrared (NIR) spectral energy distribution (SED) fitting. Our analysis is enabled by new Spitzer -IRAC 3.6 and 4.5 μ m imaging, archival prospector fully Bayesian SED fitting framework. sample contains one field UDG (DGSAT I), Virgo cluster (VCC 1287), dwarf elliptical for comparison 1122). find that optical–NIR colors three are significantly different...
We relate transitions in galaxy structure and gas content to refueling, here defined include both the external accretion internal processing needed renew reservoirs for star formation. analyze two z = 0 data sets: a high-quality ∼200 sample (the Nearby Field Galaxy Survey, release herein) volume-limited ∼3000 with reprocessed archival data. Both reach down baryonic masses ∼109 M☉ span void-to-cluster environments. Two mass-dependent are evident: (1) below "gas-richness threshold" scale (V ∼...
We present a new study investigating whether active galactic nuclei (AGN) beyond the local universe are preferentially fed via large-scale bars. Our investigation combines data from Chandra and Galaxy Zoo: Hubble (GZH) in AEGIS, COSMOS, GOODS-S surveys to create samples of face-on, disc galaxies at 0.2 < z 1.0. use novel method robustly compare sample 120 AGN host galaxies, defined have 10^42 erg/s L_X 10^44 erg/s, with inactive control matched stellar mass, rest-frame colour, size, Sersic...
ABSTRACT We use spectral energy distribution (SED) fitting to place constraints on the stellar population properties of 29 quiescent ultra-diffuse galaxies (UDGs) across different environments. fully Bayesian routine PROSPECTOR coupled with archival data in optical, near, and mid-infrared from Spitzer Wide-field Infrared Survey Explorer under assumption an exponentially declining star formation history. recover mass, age, metallicity, dust content, time scales, photometric redshifts...
Abstract Based on our dedicated Swift monitoring program, MOMO, OJ 287 is one of the best-monitored blazars in X-ray–UV–optical regime. Here, we report results from accompanying, dense, multifrequency (1.4–44 GHz) radio between 2015 and 2022 covering a broad range activity states. Fermi γ -ray observations were added. We characterize flux spectral variability detail, including discrete correlation function other analyses, discuss its connection with multiwavelength emission. Deep fades...
Optimization of casualty evacuation from conflict zones aims at increasing the chance a critically wounded soldier or civilian reaching life-saving care, minimizing secondary damages, and maximizing utilization available emergency medical resources. With emergence small, (autonomous) unmanned ground vehicles (UGVs), initial away frontlines could be possible earlier in near-continuous fashion. This study evaluates limits increased efficiency employing autonomous UGVs capable transporting one...
The Spitzer Survey of Stellar Structure in Galaxies (S^4G), together with its Early Type Galaxy (ETG) extension, stands as the most extensive dataset deep uniform mid-infrared (mid-IR; 3.6 and 4.5$,μm) imaging for a sample 2817$ nearby (d<40 ,Mpc) galaxies. However, velocity criterion used to select original results an additional 422 galaxies without i detection that should have been included S^4G on basis their optical recession velocities. In order create complete magnitude-, size-,...
We study the m=1 distortions (lopsidedness) in stellar components of 167 nearby galaxies that span a wide range morphologies and luminosities. confirm previous findings 1) high incidence lopsidedness distributions, 2) increasing as function radius out to at least 3.5 exponential scale lengths, 3) greater lopsidedness, over these radii, for later type lower surface brightness. Additionally, magnitude correlates with character spiral arms (stronger arm patterns occur less lopsidedness), is not...
We have identified 15 extended ultraviolet (XUV) disks in a largely field sample of 38 E/S0 galaxies that stellar masses primarily below ∼4 × 1010 M☉ and comparable numbers on the red blue sequences. use new purely quantitative XUV-disk definition designed with reference to "Type 1" found literature, requiring UV extension relative UV-defined star formation threshold radius. The 39% ± 9% frequency for these E/S0s is roughly twice ∼20% reported late-type (although differences criteria...
The morphology of galaxies can be quantified to some degree using a set scale-invariant parameters. Concentration (C), Asymmetry (A), Smoothness (S), the Gini index (G), relative contribution brightest pixels second order moment flux (M20), ellipticity (E), and (GM) have all been applied morphologically classify at various wavelengths. Here we present catalog these parameters for Spitzer Survey Stellar Structure in Galaxies (S4G), volume-limited near-infrared imaging survey nearby 3.6 4.5...