Teresa Ashcraft
A5036374863- Astronomy and Astrophysical Research
- Galaxies: Formation, Evolution, Phenomena
- Gamma-ray bursts and supernovae
- Adaptive optics and wavefront sensing
- Astrophysical Phenomena and Observations
- Stellar, planetary, and galactic studies
- Radio Astronomy Observations and Technology
- Astronomical Observations and Instrumentation
- Geophysics and Gravity Measurements
- CCD and CMOS Imaging Sensors
- Solar and Space Plasma Dynamics
- Ionosphere and magnetosphere dynamics
- Astro and Planetary Science
- Particle Accelerators and Free-Electron Lasers
- Astrophysics and Cosmic Phenomena
- Pulsars and Gravitational Waves Research
- Mechanics and Biomechanics Studies
- Computational Physics and Python Applications
- Scientific Measurement and Uncertainty Evaluation
- Astrophysics and Star Formation Studies
- Advanced Image Processing Techniques
- Particle accelerators and beam dynamics
- Calibration and Measurement Techniques
- Climate Change Communication and Perception
- Laser Design and Applications
Arizona State University
2009-2024
Eckerd College
2023
Idaho State Department of Education
2020
Louisiana State University
2007-2010
The University of Texas at Austin
2010
Abstract The UltraViolet Imaging of the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey Fields (UVCANDELS) survey is a Hubble Space Telescope (HST) Cycle-26 Treasury Program, allocated in total 164 orbits primary Wide-Field Camera 3 Ultraviolet and VISible light F275W imaging with coordinated parallel Advanced for Surveys F435W imaging, on four five premier extragalactic fields: GOODS-N, GOODS-S, EGS, COSMOS. We introduce this by presenting comprehensive analysis absolute...
The reionization of the Universe is one most important topics present day astrophysical research. plausible candidates for process are star-forming galaxies, which according to predictions majority theoretical and semi-analytical models should dominate HI ionizing background at z~3. We aim measuring Lyman continuum escape fraction, key parameters compute contribution galaxies UV background. have used ultra-deep U-band imaging (U=30.2mag 1sigma) by LBC/LBT in CANDELS/GOODS-North field, as...
Abstract UVCANDELS is a Hubble Space Telescope Cycle-26 Treasury Program awarded 164 orbits of primary ultraviolet (UV) F275W imaging and coordinated parallel optical F435W in four CANDELS fields—GOODS-N, GOODS-S, EGS, COSMOS—covering total area ∼426 arcmin 2 . This ∼2.7 times larger than the covered by previous deep-field space UV data combined, reaching depth about 27 28 ABmag (5 σ 0.”2 apertures) for F435W, respectively. Along with new photometric catalogs, we present an analysis...
Abstract The James Webb Space Telescope (JWST) North Ecliptic Pole (NEP) Time-domain Field (TDF) is a >14′ diameter field optimized for multiwavelength time-domain science with JWST. It has been observed across the electromagnetic spectrum both from ground and space, including Hubble (HST). As part of HST observations over three cycles (the “TREASUREHUNT” program), deep images were obtained Wide Camera on Advanced Surveys in F435W F606W that cover almost entire JWST NEP TDF. Many...
Abstract The UltraViolet Imaging of the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey Fields (UVCANDELS) survey provided ultraviolet F275W imaging with coordinated parallel optical F435W in four five CANDELS fields: GOODS-N, GOODS-S, EGS, and COSMOS, covering a total area ∼426 arcmin 2 . UVCANDELS takes primary WFC3/UVIS exposures at uniform 3-orbit depth ACS (in parallel) slightly varying due to roll angle constraints overlap from increased field view camera, reaching...
The eclipsing low-mass X-ray binary 4U 1822-371 is the prototypical accretion disk corona (ADC) system. We have obtained new time-resolved UV spectroscopy of with Advanced Camera for Surveys/Solar Blind Channel (ACS/SBC) on Hubble Space Telescope (HST) and V- J-band photometry 1.3-m SMARTS telescope at CTIO. use data to construct its UV/optical spectral energy distribution orbital light curve in UV, V, J bands. derive an improved ephemeris optical eclipses confirm that period changing...
We present two epochs of coordinated X-ray–optical timing observations the black hole candidate Swift J1753.5−0127 during its 2005 outburst. The first epoch in July occurred at outburst peak. Two consecutive nights using McDonald Observatory Argos camera with Rossi X-ray Timing Explorer show a consistent correlation an immediate response and extended tail lasting ∼5 s. properties variability are thermal reprocessing accretion disc. shortness lag suggests short orbital period that recently...
Abstract The UltraViolet imaging of the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey Fields (UVCANDELS) program provides deep Hubble Space Telescope (HST) F275W and F435W over four CANDELS fields (GOODS-N, GOODS-S, COSMOS, Extended Groth Strip). We combine this newly acquired UV with existing HST from as well ancillary data to obtain robust photometric redshifts reliable estimates for galaxy physical properties 150,000 galaxies in ∼430 arcmin 2 UVCANDELS area. Here, we...
We present a study of the trade-off between depth and resolution using large number U-band imaging observations in GOODS-North field from Large Binocular Camera (LBC) on Telescope (LBT). Having acquired over 30 hr data (315 images with 5–6 minutes exposures), we generated multiple image mosaics, starting best atmospheric seeing (FWHM ≲ 08), which constitute ∼10% total set. For subsequent added larger values until final, deepest mosaic included all FWHM 18 (∼94% set). From made object...
We obtained 838 Sloan r-band images (~28 hrs) of the GOODS-North field with Large Binocular Camera (LBC) on Telescope in order to study presence extended, low surface brightness features galaxies and investigate trade-off between image depth resolution. The individual were sorted by effective seeing, which allowed for optimal resolution mosaics be created all seeing FWHM < 0.9" 2.0", respectively. Examining bright their substructure as well accurately deblending overlapping objects requires...
We present results of optical and infrared photometric monitoring the eclipsing low-mass X-ray binary V395 Car (2S 0921−630). Our observations reveal a clear, repeating orbital modulation with an amplitude about 1 mag in B V, little less J. Combining our data archival spanning 20 years, we derive updated ephemeris period 9.0026 ± 0.0001 d. attribute to combination changing aspect irradiated face companion star eclipses accretion disc around neutron star. Both appear be necessary as secondary...
Abstract We present the results of deep ground-based U -band imaging Extended Groth Strip (EGS) field, and creation a best resolution mosaic depth following seeing-sorted stacking method Ashcraft et al. The analysis uses 324 images taken from 2012 March to 2021 June using Large Binocular Camera. includes 16.4% with FWHM ≤ 0.″9, while 73.5% 1.″6. Each image’s zero-point was matched SDSS u , account for transparency variations. Images stellar ellipticity (1 − b / ) ≥ 0.08 were omitted. find...
Several luminosity indicators have been found for gamma-ray bursts (GRBs) wherein measurable light-curve and spectral properties are well correlated with the peak luminosity. papers each applied one different relation to find redshifts BATSE GRBs claim identify specific z > 8. The existence of such high-redshift events is not surprising, as has enough sensitivity see them expected out redshift first star formation. To improve results we used five relations updated calibrations determine...
Abstract We present the results of deep, ground based U -band imaging with Large Binocular Telescope Cosmic Evolution Survey field as part near-UV program, UVCANDELS. utilize a seeing sorted stacking method along night-to-night relative transparency corrections to create optimal depth and resolution mosaics in -band, which are capable reaching point source magnitudes AB∼26.5 mag at 3 σ . These ground-based bridge wavelength gap between Hubble Space WFC3 F275W ACS F435W images necessary...
UVCANDELS is a HST Cycle-26 Treasury Program awarded 164 orbits of primary ultraviolet (UV) F275W imaging and coordinated parallel optical F435W in four CANDELS fields: GOODS-N, GOODS-S, EGS, COSMOS, covering total area $\sim426$ arcmin$^2$. This $\sim2.7$ times larger than the covered by previous deep-field space UV data combined, reaching depth about 27 28 ABmag ($5\sigma$ $0.2"$ apertures) for F435W, respectively. Along with new photometric catalogs, we present an analysis rest-frame...
The JWST North Ecliptic Pole (NEP) Time Domain Field (TDF) is a $>$14 arcmin diameter field optimized for multi-wavelength time-domain science with JWST. Its location within JWST's northern continuous viewing zone offers optimal conditions studies JWST, ensuring year-round observability, absence of bright stars, and minimal Zodiacal foreground interference. It has been observed across the electromagnetic spectrum both from ground space, including Hubble Space Telescope (HST). As part HST...
The UltraViolet imaging of the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey Fields (UVCANDELS) program provides deep HST F275W and F435W over four CANDELS fields (GOODS-N, GOODS-S, COSMOS, EGS). We combine this newly acquired UV with existing from as well ancillary data to obtain robust photometric redshifts reliable estimates for galaxy physical properties 150,000 galaxies in $\sim$430 arcmin$^2$ UVCANDELS area. Here, we leverage power new photometry not only improve...
Abstract We present the optimal resolution and depth U -filter mosaics using seeing-sorted method of Ashcraft et al. on deep, ground-based -bandimaging Great Observatories Origins Deep Survey South field as part near-UV imaging program UVCANDELS. use -bandimages obtained with VIsible Multi-Object Spectrograph European Southern Observatory Very Large Telescope by Nonino Our best mosaic includes images a seeing full-width half maximum (FWHM) ≤ 0.″8, encompasses 50% data. FWHM 1.″5,...
We have developed a Java-based teaching tool, "Appreciating Hubble at Hyper-speed" ("AHaH"), intended for use by students and instructors in beginning astronomy cosmology courses, which we made available online. This tool lets the user hypothetically traverse Ultra Deep Field (HUDF) three dimensions over 500x10^12 times speed of light, from redshifts z=0 today to z=6, about 1 Gyr after Big Bang. Users may also view Universe various configurations two different geometry modes - standard that...
We present the results of deep, ground based U-band imaging with Large Binocular Telescope Cosmic Evolution Survey (COSMOS) field as part near-UV program, UVCANDELS. utilize a seeing sorted stacking method along night-to-night relative transparency corrections to create optimal depth and resolution mosaics in U-band, which are capable reaching point source magnitudes AB 26.5 mag at 3 sigma. These bridge wavelength gap between HST WFC3 F27W ACS F435W images necessary understand galaxy...