A5078180982- Astronomy and Astrophysical Research
- Stellar, planetary, and galactic studies
- CCD and CMOS Imaging Sensors
- Calibration and Measurement Techniques
- Galaxies: Formation, Evolution, Phenomena
- Adaptive optics and wavefront sensing
- Astronomical Observations and Instrumentation
- Advanced Semiconductor Detectors and Materials
- Infrared Target Detection Methodologies
- Scientific Research and Discoveries
- Gamma-ray bursts and supernovae
- Astrophysics and Star Formation Studies
- Spectroscopy and Chemometric Analyses
- Particle Detector Development and Performance
- History and Developments in Astronomy
- Spectroscopy Techniques in Biomedical and Chemical Research
- Atmospheric Ozone and Climate
- Historical Astronomy and Related Studies
- Advanced Image Processing Techniques
- Cosmology and Gravitation Theories
- Dark Matter and Cosmic Phenomena
- Radio Astronomy Observations and Technology
- Superconducting and THz Device Technology
- Advanced Chemical Sensor Technologies
- Astrophysical Phenomena and Observations
Goddard Space Flight Center
2018-2025
University of Wisconsin–Madison
2012-2018
We present results from an optical photometric and spectroscopic survey of the young stellar population in L1641, low-density star-forming region Orion A cloud south Nebula Cluster (ONC). Our goal is to determine whether L1641 has a large enough low-mass make known lack high-mass stars statistically-significant demonstration environmental dependence upper mass initial function (IMF). sample consists IR-excess objects selected Spitzer/IRAC non-excess photometry. have spectral confirmation 864...
The Nancy Grace Roman Space Telescope (Roman) formerly known as the Wide-Field Infrared Survey will answer fundamental questions about evolution of dark energy over time and expand catalog exoplanets into new regions parameter space. Using a Hubble-sized mirror 18 newly developed HgCdTe 4K × photodiode arrays (H4RG-10), measure positions shapes hundreds millions galaxies, light curves thousands supernovae, microlensing signals thousand toward bulge Galaxy. These measurements require...
The Pandora SmallSat is a NASA flight project aimed at studying the atmospheres of exoplanets -- planets orbiting stars outside our Solar System. will provide first dataset simultaneous, multiband (visible and NIR), long-baseline observations their host stars. an ambitious that fly 0.44 m telescope in small form factor. To achieve scientific goals, mission requires departure from traditional cost-schedule paradigm half-meter-class observatories. achieves this by leveraging existing...
The Nancy Grace Roman Space Telescope will study the dark matter content of universe, expansion history and diversity exoplanets in Galaxy using unprecedented wide-field infrared surveys. accomplish this a focal plane 18 newly developed HgCdTe detectors. Roman's detectors, H4RG-10, are 4 K×4 K format 10-micron pixel pitch devices manufactured by Teledyne Imaging Sensors. After acceptance testing at Goddard Detector Characterization Lab, flight detectors were selected for plane. Histograms...
The Robert Stobie Spectrograph Near Infrared Instrument (RSS-NIR), a prime focus facility instrument for the 11-meter Southern African Large Telescope (SALT), is well into its laboratory integration and testing phase. RSS-NIR will initially provide imaging single or multi-object medium resolution spectroscopy in an 8 arcmin field of view at wavelengths 0.9 - 1.7 μm. Future modes, including tunable Fabry-Perot spectral polarimetry, have been designed can be easily added later. mate to...
The University of Wisconsin Madison is building a NIR spectrograph (RSS-NIR) for the Southern African Large Telescope. detector system uses H2RG HdCdTe 1.7 μm cutoff array. We performed tests to measure and characterize persistence inform strategies mitigate this effect. These use up-the- ramp group samples get finer time resolution release persistence. share these test results. also present preliminary results dependence on temperature. conclude with an outline assessment calibration scheme.
We describe the results of principal component analysis (PCA) up-the-ramp sampled IR array data from HST WFC3 IR, JWST NIRSpec, and prototype WFIRST WFI detectors. These systems use respectively Teledyne H1R, H2RG, H4RG-10 near-IR detector arrays with a variety controllers. The PCA shows that Legendre polynomials approximate components these (i.e. they roughly diagonalize covariance matrix). In contrast to monomial basis is widely used for polynomial fitting linearization today, are an...
Pandora is a SmallSat mission designed to study the atmospheres of exoplanets, and was selected as part NASA's Astrophysics Pioneers Program. Transmission spectroscopy transiting exoplanets provides our best opportunity identify makeup planetary in coming decade. Stellar brightness variations due star spots, however, can impact these measurements contaminate observed spectra. Pandora's goal disentangle planet signals transmission spectra reliably determine exoplanet atmosphere compositions....
Teledyne's H4RG, H2RG, and H1RG near-infrared array detectors provide reference pixels embedded in their data streams. Although they do not respond to light, the electronically mimic normal track correlated read noise. We describe how can be used with linear algebra training optimally reduce Simple improved subtraction (SIRS) works common detector clocking patterns and, when applicable, relies only on postprocessing existing so long as are available. The resulting correction is optimal, a...
To study the effect of supermassive black holes (SMBHs) on their host galaxies it is important to hosts when SMBH near its peak activity. A method investigate high luminosity quasars obtain optical spectra at positions offset from nucleus where relative contribution quasar and are comparable. However, these extended radii galaxy surface brightness often low (20-22 mag per arcsec$^{2}$) resulting spectrum might have such S/N that hinders analysis with standard stellar population modeling...
The Pandora SmallSat is a NASA flight project designed to study the atmospheres of exoplanets. Transmission spectroscopy transiting exoplanets provides our best opportunity identify makeup planetary in coming decade, and key science driver for HST JWST. Stellar photospheric inhomogeneity due star spots, however, has been shown contaminate observed spectra these high-precision measurements. will address problem stellar contamination by collecting long-duration photometric observations sampled...
Surveys in space and time are key to answering outstanding questions astrophysics. The power study very large numbers of stars, galaxies, transient events over portions the sky different scales has repeatedly led new breakthroughs. Nancy Grace Roman Space Telescope (Roman), NASA's next Astrophysics Flagship mission, elevates wide field domain survey observations previously inaccessible scales. carries Wide Field Instrument (WFI), which provides visible near-infrared imaging spectroscopy with...
REX is a NASA Astrophysics Small Explorer Mission concept to chart the history of cosmic dawn in unprecedented detail space and time. will identify very young galaxies black holes by means their powerful Lyman alpha (Lyα) line emission using about 10 narrow-bandpass filters covering 100 square degrees. The strong identifies samples most actively star-forming early galaxies, believed be drivers reionization. Moreover, mapping distribution properties emitting population reveal ionized neutral...
We report on the status of detector system for Robert Stobie Spectrograph Near Infrared Arm (RSS-NIR) Southern African Large Telescope (SALT). The is a HAWAII-2RG array with 1.7 μm cutoff wavelength. controller incorporates Teledyne cryogenic SIDECAR ASIC board inside dewar and an FPGA interface card, developed by Inter-University Centre Astronomy Astrophysics (IUCAA), outside dewar. Data acquisition software written IUCAA runs under Linux operating communicates to through USB fiber optic...
Pandora is a low-cost space telescope designed to measure the composition of distant transiting planets. The observatory with capability measuring precision photometry simultaneously nearinfrared spectroscopy, enabling scientists disentangle stellar activity from subtle signature planetary atmosphere. broad-wavelength coverage will provide constraints on spot and faculae covering fractions low-mass exoplanet host stars impact these active regions exoplanetary transmission spectra....
At the University of Wisconsin-Madison, we are building and testing near-infrared (NIR) spectrograph for Southern African Large Telescope—RSS-NIR. RSS-NIR will be an enclosed cooled integral field spectrograph. The detector system uses a HAWAII-2RG (H2RG) HgCdTe from Teledyne controlled by SIDECAR ASIC Inter-University Centre Astronomy Astrophysics (IUCCA) ISDEC card. We have successfully characterized optimized report on optimization steps performance system. reduced CDS read noise to ∼20...
In this age of multi-messenger astronomy precipitated by the LIGO/Virgo observation GW 170817, it is more important than ever to have instruments throughout EM spectrum perform follow-up observations. With installation an upgraded detector system and cross-dispersed ruled ZnSe grisms, development data reduction pipelines, Rapid infrared IMAger Spectrometer (RIMAS) ready be at frontier rapidly blossoming field. RIMAS a near-infrared imager spectrometer (R≈25, R≈250, R≈4000) designed observe...
The PRime-focus Infrared Microlensing Experiment (PRIME) camera is part of the joint NASA-JAXA project in support spaceflight Roman Space Telescope development. It designed to accommodate needs large-scale survey microlensing events Galactic bulge. placed prime focus 1.8-m telescope dedicated this project. With four large-format infrared detectors, instrument covers a field view about 1.3 square degrees. Over few years preceding and during operations Telescope, will be used for continuous...