A5032078360- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Adaptive optics and wavefront sensing
- Calibration and Measurement Techniques
- Astro and Planetary Science
- Astrophysics and Star Formation Studies
- Astronomical Observations and Instrumentation
- Galaxies: Formation, Evolution, Phenomena
- Optical Systems and Laser Technology
- Spectroscopy and Laser Applications
- Astrophysical Phenomena and Observations
- CCD and CMOS Imaging Sensors
- Gamma-ray bursts and supernovae
- Space Exploration and Technology
- History and Developments in Astronomy
- Particle Accelerators and Free-Electron Lasers
- Solar and Space Plasma Dynamics
- Astrophysics and Cosmic Phenomena
- Photonic and Optical Devices
- Additive Manufacturing and 3D Printing Technologies
- Planetary Science and Exploration
- GNSS positioning and interference
- Spacecraft and Cryogenic Technologies
- Optical Coatings and Gratings
- Superconducting Materials and Applications
University of California, Santa Cruz
2018-2024
University of California, Irvine
2023
University of Arizona
2023
Indian Institute of Astrophysics
2023
University of Florida
2012-2021
Weatherford College
2020
University of Bern
2010
University of Colorado Boulder
2010
Observations of binary stars containing an accreting black hole or neutron star often show x-ray emission extending to high energies (>10 kilo--electron volts), which is ascribed accretion disk corona energetic particles akin those seen in the solar corona. Despite their ubiquity, physical conditions coronae remain poorly constrained. Using simultaneous infrared, optical, x-ray, and radio observations Galactic system V404 Cygni, showing a rapid synchrotron cooling event its 2015 outburst, we...
As we begin to discover rocky planets in the habitable zone of nearby stars with missions like TESS and CHEOPS, will need quick advancements on instrumentation observational techniques that enable us answer key science questions, such as What are atmospheric characteristics planets? How common Earth-like biosignatures planets?} similar or dissimilar those Earth? Over next decade expect have discovered several Earth-analog candidates, but not tools study atmospheres all them detail....
We present results from end-to-end simulations of observations designed to constrain the rate change in expansion history Universe using redshift drift Lyman-$\alpha$ forest absorption lines along lines-of-sight toward bright quasars. For our we take extracted Keck/HIRES spectra quasars at $z>3$, and compare these real quasar with mock generated via Monte Carlo realizations. use assess potential for a dedicated observatory detect drift, quantify telescope spectrograph requirements...
Adaptive optics systems that use adaptive secondary mirrors can potentially broaden the of AO in astronomy. However, unlike post-focal plane systems, ASM-based require large (200-1500 mm diameter), curved, aspheric membranes to replicate standard telescope they replace. A key limitation current devices is cost (and associated risk) manufacturing thin (2-3 mm) curved facesheets. We have developed a new approach for fabrication these facesheets initially uses flat, polished sheets glass are...
We present the design of SCALES (Slicer Combined with Array Lenslets for Exoplanet Spectroscopy) a new 2-5 micron coronagraphic integral field spectrograph under construction Keck Observatory. enables low-resolution (R∼50) spectroscopy, as well medium-resolution (R∼4,000) spectroscopy goal discovering and characterizing cold exoplanets that are brightest in thermal infrared. Additionally, has 12x12" field-of-view imager will be used general adaptive optics science at Keck. SCALES's...
We summarize the red channel (2-5 micron) of Planetary Systems Imager (PSI), a proposed second-generation instrument for TMT. Cold exoplanets emit majority their light in thermal infrared, which means these can be detected at more modest contrast than other wavelengths. PSI-Red will able to detect and characterize wide variety exoplanets, including radial-velocity planets on orbits, accreting protoplanets nearby star-forming regions, reflected-light around nearest stars. feature an imager,...
Concave blazed gratings greatly simplify the architecture of spectrographs by reducing number optical components. The production these using diamond-machining offers practically no limits in design grating substrate shape, with possibility making large sag freeform surfaces unlike alternative and traditional method holography ion etching. In this paper, we report on technological challenges progress curved an ultra-high precision 5 axes Moore-Nanotech machine. We describe their...
SCALES (Santa Cruz Array of Lenslets for Exoplanet Spectroscopy) is a 2-5 micron high-contrast lenslet integral-field spectrograph (IFS) driven by exoplanet characterization science requirements and will operate at W. M. Keck Observatory. Its fully cryogenic optical train uses custom silicon array, selectable coronagraphs, dispersive prisms to carry out integral field spectroscopy over 2.2 arcsec view with low (< 300) spectral resolution. A small, dedicated section the array feeds an image...
A next-generation instrument named, Slicer Combined with Array of Lenslets for Exoplanet Spectroscopy (SCALES), is being planned the W. M. Keck Observatory. SCALES will have an integral field spectrograph (IFS) and a diffraction-limited imaging channel to discover spectrally characterize directly imaged exoplanets. Operating at thermal infrared wavelengths (1-5 μm, goal 0.6-5 μm), designed cover 12′′ × view low distortions high throughput. Apart from expanding mid-infrared science cases...
The Mid-resolution InfRAreD Astronomical Spectrograph (MIRADAS, a near-infrared multi-object echelle spectrograph operating at spectral resolution R=20,000 over the 1-2.5μm bandpass) was selected in 2010 by Gran Telescopio Canarias (GTC) partnership as next-generation for world's largest optical/infrared telescope, and is being developed an international consortium. MIRADAS consortium includes University of Florida, Universidad de Barcelona, Complutense Madrid, Instituto Astrofísica...
The Mid-resolution InfRAreD Astronomical Spectrograph (MIRADAS, a near-infrared multi-object echelle spectrograph operating at spectral resolution R=20,000 over the 1-2.5μm bandpass) was selected by Gran Telescopio Canarias (GTC) partnership as next-generation for world's largest optical/infrared telescope, and is being developed an international consortium. MIRADAS consortium includes University of Florida, Universidad de Barcelona, Complutense Madrid, Instituto Astrofísica Canarias,...
We present the data reduction pipeline, MEAD, for Arizona Lenslets Exoplanet Spectroscopy (ALES), first thermal infrared integral field spectrograph designed high-contrast imaging. ALES is an upgrade of LMIRCam, 1 - 5 μm imaging camera Large Binocular Telescope, capable observing astronomical objects in (3 μm) to produce simultaneous spatial and spectral cubes. The pipeline currently perform L-band (2.8 4.2 cube reconstruction, relying on methods used extensively by current...
The Canarias InfraRed Camera Experiment (CIRCE) is a near-infrared (1–2.5[Formula: see text][Formula: text]m) imager, polarimeter and low-resolution spectrograph operating as visitor instrument for the Gran Telescopio (GTC) 10.4-m telescope. It was designed built largely by graduate students postdocs, with help from University of Florida (UF) astronomy engineering group, funded UF US National Science Foundation. CIRCE intended to fill gap in capabilities prior arrival Especrografo...
The Planetary Systems Imager (PSI) is a proposed instrument for the Thirty Meter Telescope (TMT) that provides an extreme adaptive optics (AO) correction to multi-wavelength suite optimized high contrast science. PSI's broad range of capabilities, spanning imaging, polarimetry, integral field spectroscopy, and resolution spectroscopy from 0.6–5 μm, with potential channel at 10 will enable breakthrough science in areas exoplanet formation evolution. Here, we present preliminary optical design...
SCALES is a high-contrast, infrared coronagraphic imager and integral field spectrograph (IFS) to be deployed behind the W.M. Keck Observatory adaptive optics system. A reflective optical design allows diffraction-limited imaging over large wavelength range (1.0 - 5.0 µm). microlens array-based IFS coupled with lenslet reformatter ("slenslit") allow spectroscopy at both low (R = 35 250) moderate 2000 6500) spectral resolutions. The range, performance, high contrast coronagraphy cryogenic...
CIRCE is a near-infrared (1-2.5 micron) imager, polarimeter and low-resolution spectrograph intended as visitor instrument for the Gran Telescopio Canarias 10.-4m telescope. It was built largely by graduate students postdocs, with help from UF astronomy engineering group, funded University of Florida U.S. National Science Foundation. to fill gap in time between GTC first light arrival EMIR, will also provide following scientific capabilities compliment EMIR after its arrival: high-...
We describe the design, development, and laboratory test results of cryogenic probe arms feeding deployable integral field units (IFUs) for Mid-resolution InfRAreD Astronomical Spectrograph (MIRADAS) - a near-infrared multi-object echelle spectrograph 10.4-meter Gran Telescopio Canarias. MIRADAS selects targets using 20 positionable pickoff mirror optics on arms, each 3.7x1.2-arcsec view to units, while maintaining excellent diffraction-limited image quality. The are based concept developed...
We present end-to-end simulations of SCALES, the third generation thermal-infrared diffraction limited imager and low/med-resolution integral field spectrograph (IFS) being designed for Keck. The 2-5 micron sensitivity SCALES enables detection characterization a wide variety exoplanets, including exoplanets detected through long-baseline astrometry, radial-velocity planets on orbits, accreting protoplanets in nearby starforming regions, reflected-light around nearest stars. simulation goal...
SCALES (Slicer Combined with an Array of Lenslets for Exoplanet Spectroscopy) is a 2 - 5 micron high-contrast lenslet-based integral field spectrograph (IFS) designed to characterize exoplanets and their atmospheres. Like other IFSs, produces short micro-spectrum each lenslet's micro-pupil. We have developed image slicer that sits behind the lenslet array & dissects rearranges subset micro-pupils into pseudo-slit. The combination (or slenslit) allows produce much longer spectra, thereby...
We present the optical design of Red arm (operating at 2-5 µm) Planetary Systems Imager (PSI). At heart this PSI is a 180x180 silicon lenslet array which will allow diffraction-limited low- resolution integral field spectroscopy over view 1.5 arcseconds on Thirty Meter Telescope. The entrance window, array, and dispersing prisms are only refractive optics; all other optics diamond-turned, off-axis, aspherical, gold-coated aluminum designed with 'bolt-and-go' opto-mechanical approach. use...