Chad F. Bender
A5023928187- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Astrophysics and Star Formation Studies
- Astro and Planetary Science
- Gamma-ray bursts and supernovae
- Adaptive optics and wavefront sensing
- Astronomical Observations and Instrumentation
- Spectroscopy and Laser Applications
- Advanced Fiber Laser Technologies
- Atmospheric Ozone and Climate
- Galaxies: Formation, Evolution, Phenomena
- Calibration and Measurement Techniques
- Astrophysical Phenomena and Observations
- Solar and Space Plasma Dynamics
- Advanced Frequency and Time Standards
- Space Exploration and Technology
- Geophysics and Gravity Measurements
- Advanced Measurement and Metrology Techniques
- Photonic and Optical Devices
- High-pressure geophysics and materials
- Advanced Fiber Optic Sensors
- Photonic Crystal and Fiber Optics
- Inertial Sensor and Navigation
- CCD and CMOS Imaging Sensors
- Geophysics and Sensor Technology
University of Arizona
2016-2024
Texas Christian University
2021
Pennsylvania State University
2010-2019
Las Cumbres Observatory Global Telescope Network
2018
NASA Exoplanet Science Institute
2016-2017
IBM (United States)
2008
Stony Brook University
2001-2008
United States Naval Research Laboratory
2008
Naval Research Laboratory Remote Sensing Division
2008
State University of New York
2001-2006
Abstract We describe the Sloan Digital Sky Survey IV (SDSS-IV), a project encompassing three major spectroscopic programs. The Apache Point Observatory Galactic Evolution Experiment 2 (APOGEE-2) is observing hundreds of thousands Milky Way stars at high resolution and signal-to-noise ratios in near-infrared. Mapping Nearby Galaxies (MaNGA) survey obtaining spatially resolved spectroscopy for nearby galaxies (median <?CDATA $z\sim 0.03$?> ). extended Baryon Oscillation Spectroscopic (eBOSS)...
The Sloan Digital Sky Survey (SDSS) has been in operation since 2000 April. This paper presents the Tenth Public Data Release (DR10) from its current incarnation, SDSS-III. data release includes first spectroscopic Apache Point Observatory Galaxy Evolution Experiment (APOGEE), along with Baryon Oscillation Spectroscopic (BOSS) taken through 2012 July. APOGEE instrument is a near-infrared R ∼ 22,500 300 fiber spectrograph covering 1.514–1.696 μm. survey studying chemical abundances and radial...
This paper documents the seventeenth data release (DR17) from Sloan Digital Sky Surveys; fifth and final fourth phase (SDSS-IV). DR17 contains complete of Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey, which reached its goal surveying over 10,000 nearby galaxies. The MaNGA Stellar Library (MaStar) accompanies this data, providing observations almost 30,000 stars through instrument during bright time. also Galactic Evolution Experiment 2 (APOGEE-2) survey publicly...
The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) has been in operation since 2014 July. This paper describes second data release from this phase, and 14th SDSS overall (making Data Release Fourteen or DR14). makes taken by SDSS-IV its first two years (2014–2016 July) public. Like all previous releases, DR14 is cumulative, including most recent reductions calibrations phase began operations 2000. New public extended Baryon Oscillation Spectroscopic Survey; Apache Point...
This paper documents the sixteenth data release (DR16) from Sloan Digital Sky Surveys; fourth and penultimate phase (SDSS-IV). is first of southern hemisphere survey Apache Point Observatory Galactic Evolution Experiment 2 (APOGEE-2); new APOGEE-2 North are also included. DR16 notable as final for main cosmological program Extended Baryon Oscillation Spectroscopic Survey (eBOSS), all raw reduced spectra that project released here. includes Time Domain (TDSS) SPectroscopic IDentification...
Abstract APOGEE-2 is a high-resolution, near-infrared spectroscopic survey observing ∼3 × 10 5 stars across the entire sky. It successor to APOGEE and part of Sloan Digital Sky Survey IV (SDSS-IV). expanding on APOGEE’s goals addressing critical questions stellar astrophysics, populations, Galactic chemodynamical evolution using (1) an enhanced set target types (2) second spectrograph at Las Campanas Observatory in Chile. targeting red giant branch clump stars, RR Lyrae, low-mass dwarf young...
The Apache Point Observatory Galactic Evolution Experiment (APOGEE), part of the Sloan Digital Sky Survey III, explores stellar populations Milky Way using 2.5-m telescope linked to a high resolution (R~22,500), near-infrared (1.51-1.70 microns) spectrograph with 300 optical fibers. For over 150,000 predominantly red giant branch stars that APOGEE targeted across bulge, disks and halo, collected S/N (>100 per half-resolution element) spectra provide accurate (~0.1 km/s) radial velocities,...
The eighteenth data release of the Sloan Digital Sky Surveys (SDSS) is first one for SDSS-V, fifth generation survey. SDSS-V comprises three primary scientific programs, or "Mappers": Milky Way Mapper (MWM), Black Hole (BHM), and Local Volume (LVM). This contains extensive targeting information two multi-object spectroscopy programs (MWM BHM), including input catalogs selection functions their numerous objectives. We describe production databases calibration- scientifically-focused...
We describe and characterize a 25 GHz laser frequency comb based on cavity-filtered erbium fiber mode-locked laser. The provides uniform array of optical frequencies spanning 1450 nm to 1700 nm, is stabilized by use global positioning system referenced atomic clock. This was deployed at the 9.2 m Hobby-Eberly telescope McDonald Observatory where it used as radial velocity calibration source for fiber-fed Pathfinder near-infrared spectrograph. Stellar targets were observed in three echelle...
The Habitable-Zone Planet Finder is a stabilized, fiber-fed, NIR spectrograph being built for the 10m Hobby- Eberly telescope (HET) that will be capable of discovering low mass planets around M dwarfs. optical design HPF white pupil layout in vacuum cryostat cooled to 180 K. uses gold-coated mirrors, mosaic echelle grating, and single Teledyne Hawaii-2RG (H2RG) detector with 1.7-micron cutoff covering parts information rich z, Y J bands at spectral resolution R∼50,000. unique HET requires...
We have developed an optical design for a high resolution spectrograph in response to NASA's call extreme precision Doppler spectrometer (EPDS) the WIYN telescope. Our instrument covers wavelength range of 380 930 nm using single detector and with 100,000. To deliver most stable spectrum, we avoid use image slicer, favor large (195 mm diameter) beam footprint on 1x2 mosaic R4 Echelle grating. The is based classic white pupil layout, parabolic mirror that used as main transfer collimator....
Abstract We demonstrate a path to hitherto unachievable differential photometric precisions from the ground, both in optical and near-infrared (NIR), using custom-fabricated beam-shaping diffusers produced specialized nanofabrication techniques. Such mold focal plane image of star into broad stable top-hat shape, minimizing errors due non-uniform pixel response, atmospheric seeing effects, imperfect guiding, telescope-induced variable aberrations seen defocusing. This PSF reshaping...
We use high dynamic range, high-resolution L-band spectroscopy to measure the radial velocity (RV) variations of hot Jupiter in τ Boötis planetary system. The detection an exoplanet by shift stellar spectrum alone provides a planet's minimum mass, with true mass degenerate unknown orbital inclination. Treating Boo system as flux ratio double-lined spectroscopic binary permits direct measurement well its atmospheric properties. After removing telluric absorption and cross-correlating model...
We present an empirical near-infrared (NIR) spectroscopic method for estimating M dwarf metallicities, based on features in the H band, as well implementation of a similar published K band. obtained R ∼ 2000 NIR spectra sample dwarfs using NASA IRTF-SpeX spectrograph, including 22 metallicity calibration targets that have FGK companions with known metallicities. The H-band and K-band calibrations provide equivalent fits to metallicities these binaries, accuracy ±0.12 dex. derive first...
ABSTRACT Given the potential of ensemble asteroseismology for understanding fundamental properties large numbers stars, it is critical to determine accuracy scaling relations on which these measurements are based. From several powerful validation techniques, all indications so far show that stellar radius estimates from asteroseismic accurate within a few percent. Eclipsing binary systems hosting at least one star with detectable solar-like oscillations constitute ideal test objects...
Insufficient instrument thermo-mechanical stability is one of the many roadblocks for achieving 10cm/s Doppler radial velocity (RV) precision, precision needed to detect Earth-twins orbiting Solar-type stars. Highly temperature and pressure stabilized spectrographs allow us better calibrate out instrumental drifts, thereby helping in distinguishing noise from astrophysical stellar signals. We present design performance Environmental Control System (ECS) Habitable-zone Planet Finder (HPF), a...
Abstract The Apache Point Observatory Galactic Evolution Experiment 2 (APOGEE-2) is a dual-hemisphere, near-infrared (NIR), spectroscopic survey with the goal of producing chemodynamical mapping Milky Way. targeting for APOGEE-2 complex and has evolved time. In this paper, we present updates additions to initial strategy APOGEE-2N presented in Zasowski et al. (2017). These modifications come two implementation modes: (i) “Ancillary Science Programs” competitively awarded Sloan Digital Sky...
Abstract The warm Neptune GJ 3470b transits a nearby ( d = 29 pc) bright slowly rotating M1.5-dwarf star. Using spectroscopic observations during two with the newly commissioned NEID spectrometer on WIYN 3.5 m Telescope at Kitt Peak Observatory, we model classical Rossiter–McLaughlin effect, yielding sky-projected obliquity of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>λ</mml:mi> <mml:mo>=</mml:mo> <mml:msubsup> <mml:mrow> <mml:mn>98</mml:mn>...
Abstract We present the discovery of TOI-5205b, a transiting Jovian planet orbiting solar metallicity M4V star, which was discovered using Transiting Exoplanet Survey Satellite photometry and then confirmed combination precise radial velocities, ground-based photometry, spectra, speckle imaging. TOI-5205b has one highest mass ratios for M-dwarf planets, with ratio almost 0.3%, as it orbits host star that is just 0.392 ± 0.015 M ⊙ . Its planetary radius 1.03 0.03 R J , while 1.08 0.06...
Photonics offer numerous functionalities that can be used to realize astrophotonic instruments. The most spectacular example date is the ESO Gravity instrument at Very Large Telescope in Chile. Integrated devices stand critical advantages for development, including extreme miniaturization, as well integration, superior thermal and mechanical stabilization owing small footprint, high replicability offering cost savings. Numerous technologies have been developed address shortcomings of...
Abstract We confirm TOI-4201 b as a transiting Jovian-mass planet orbiting an early M dwarf discovered by the Transiting Exoplanet Survey Satellite. Using ground-based photometry and precise radial velocities from NEID Planet Finder Spectrograph, we measure mass of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msubsup> <mml:mrow> <mml:mn>2.59</mml:mn> </mml:mrow> <mml:mo>−</mml:mo> <mml:mn>0.06</mml:mn> <mml:mo>+</mml:mo> <mml:mn>0.07</mml:mn>...
Abstract Gaia astrometry of nearby stars is precise enough to detect the tiny displacements induced by substellar companions, but radial velocity (RV) data are needed for definitive confirmation. Here we present RV follow-up observations 28 M and K with candidate astrometric which led confirmation two systems, Gaia-4b Gaia-5b, identification five systems that single lined require additional confirm as refutation 21 stellar binaries. a massive planet ( = 11.8 ± 0.7 J ) in P 571.3 1.4 day...
We present the scientific motivation and conceptual design for recently funded Habitable-zone Planet Finder (HPF), a stabilized fiber-fed near-infrared (NIR) spectrograph 10 meter class Hobby-Eberly Telescope (HET) that will be capable of discovering low mass planets around M dwarfs. The HPF cover NIR Y & J bands to enable precise radial velocities obtained on mid dwarfs, detection these stars. is comprised cryostat cooled 200K, dual fiber-feed with science calibration fiber, gold coated...
We report observations of a possible young transiting planet orbiting previously known weak-lined T-Tauri star in the 7-10 Myr old Orion-OB1a/25-Ori region. The candidate was found as part Palomar Transient Factory (PTF) Orion project. It has photometric transit period 0.448413 +- 0.000040 days, and appears both 2009 2010 PTF data. Follow-up low-precision radial velocity (RV) adaptive optics imaging suggest that is not an eclipsing binary, it unlikely background source blended with target...
We have used high-resolution spectroscopy to observe the Kepler-16 eclipsing binary as a double-lined system, and measure precise radial velocities for both stellar components. These yield dynamical mass-ratio of q=0.2994+-0.0031. When combined with inclination, i=90.3401+0.0016-0.0019 deg, measured from Kepler photometric data by Doyle et al. 2011, we derive masses components M_A=0.654+-0.017 M_sun M_B=0.1959+-0.0031 M_sun, precision 2.5% 1.5% respectively. Our results confirm at ~2% level...