Crystal L. Gnilka
A5010084277- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Astro and Planetary Science
- Astrophysics and Star Formation Studies
- Adaptive optics and wavefront sensing
- Gamma-ray bursts and supernovae
- Astrophysical Phenomena and Observations
- Galaxies: Formation, Evolution, Phenomena
- Astronomical Observations and Instrumentation
- Astronomical and nuclear sciences
- Archaeology and Historical Studies
- Ancient Egypt and Archaeology
- Space Exploration and Technology
- Radio Astronomy Observations and Technology
- Advanced Mathematical Theories and Applications
- Scientific Research and Discoveries
- Nuclear physics research studies
- Calibration and Measurement Techniques
- Biblical Studies and Interpretation
- Geochemistry and Geologic Mapping
- Historical, Religious, and Philosophical Studies
- Mathematics and Applications
- Molecular spectroscopy and chirality
- Cosmology and Gravitation Theories
- Evolutionary Algorithms and Applications
Ames Research Center
2021-2024
NASA Exoplanet Science Institute
2021-2023
California Institute of Technology
2021-2023
Georgia State University
2018-2020
Two new imaging instruments, ‘Alopeke and Zorro, were designed, built, commissioned at the Gemini-North Gemini-South telescopes in 2018 2019, respectively. Here we describe them present results from over a year of operation. The two identical instruments are based on legacy DSSI (Differential Speckle Survey Instrument) instrument, successfully used for years WIYN Gemini Hawaii Chile. Zorro dual-channel imagers having both speckle (6.7″) “wide-field” (∼1 arcminute) field-of-view options. They...
Abstract Mature super-Earths and sub-Neptunes are predicted to be ≃ Jovian radius when younger than 10 Myr. Thus, we expect find 5–15 R ⊕ planets around young stars even if their older counterparts harbor none. We report the discovery validation of TOI 1227b, a 0.85 ± 0.05 J (9.5 ) planet transiting very-low-mass star (0.170 0.015 M ⊙ every 27.4 days. 1227's kinematics strong lithium absorption confirm that it is member previously discovered subgroup in Lower Centaurus Crux OB association,...
We report the discovery and characterisation of a pair sub-Neptunes transiting bright K-dwarf TOI-1064 (TIC 79748331), initially detected in TESS photometry. To characterise system, we performed retrieved CHEOPS, TESS, ground-based photometry, HARPS high-resolution spectroscopy, Gemini speckle imaging. host star determine $T_{\rm eff, \star}=4734\pm67$ K, $R_{\star}=0.726\pm0.007$ $R_{\odot}$, $M_{\star}=0.748\pm0.032$ $M_{\odot}$. present novel detrending method based on PSF shape-change...
Context. In the age of JWST, temperate terrestrial exoplanets transiting nearby late-type M dwarfs provide unique opportunities for characterising their atmospheres, as well searching biosignature gases. this context, benchmark TRAPPIST-1 planetary system has garnered interest a broad scientific community. Aims. We report here discovery and validation two super-Earths LP 890-9 (TOI-4306, SPECULOOS-2), relatively low-activity (32 pc) M6V star. The inner planet, b, was first detected by TESS...
We present the discovery and characterisation of two transiting planets observed by \textit{TESS} in light curves young bright (V=9.67) star HD73583 (TOI-560). perform an intensive spectroscopic photometric space- ground-based follow-up order to confirm characterise system. found that is a ($\sim 500$~Myr) active with rotational period $12.08 \pm 0.11 $\,d, mass radius $ 0.73 0.02 M_\odot$ $0.65 R_\odot$, respectively. b ($P_b=6.3980420 _{ - 0.0000062 }^{+0.0000067}$ d) has $10.2...
Quaoar is a classical Trans-Neptunian Object (TNO) with an area equivalent diameter of 1,100 km and orbital semi-major axis 43.3 astronomical units. Based on stellar occultations observed between 2018 2021, inhomogeneous ring (Q1R, Quaoar's first ring) was detected around this body. Aims. A new occultation by August 9th, 2022 aiming to improve shape models the physical parameters Q1R while searching for additional material Methods. The provided nine effective chords across Quaoar, pinning...
Abstract We report the discovery and characterization of a nearby (∼85 pc), older (27 ± 3 Myr), distributed stellar population near Lower Centaurus Crux (LCC), initially identified by searching for stars comoving with candidate transiting planet from TESS (HD 109833; TOI 1097). determine association membership using Gaia kinematics, color–magnitude information, rotation periods members. measure its age isochrones, gyrochronology, Li depletion. While is known populations LCC, we find that it...
Abstract Directly imaging temperate rocky planets orbiting nearby, Sun-like stars with a 6 m class IR/O/UV space telescope, recently dubbed the Habitable Worlds Observatory, is high-priority goal of Astro2020 Decadal Survey. To prepare for future direct (DI) surveys, list potential targets should be thoroughly vetted to maximize efficiency and scientific yield. We present an analysis archival radial velocity data southern from NASA/NSF Extreme Precision Radial Velocity (EPRV) Working Group’s...
We report the discovery of two planetary systems around comoving stars; TOI-2076 (TIC 27491137) and TOI-1807 180695581). is a nearby (41.9 pc) multi-planetary system orbiting young (204$\pm$50 Myr), bright (K = 7.115 in TIC v8.1). hosts single transiting planet, similarly (42.58pc), (180$\pm$40 bright. Both targets exhibit significant, periodic variability due to star spots, characteristic their ages. Using photometric data collected by TESS we identify three planets with radii...
Large sub-Neptunes are uncommon around the coolest stars in Galaxy and rarer still those that metal-poor. However, owing to large planet-to-star radius ratio, these planets highly suitable for atmospheric study via transmission spectroscopy infrared, such as with JWST. Here we report discovery validation of a sub-Neptune orbiting thick-disk, mid-M dwarf star TOI-2406. We first infer properties host by analysing star's near-infrared spectrum, spectral energy distribution, Gaia parallax. use...
We report the detection and characterization of transiting sub-Neptune TOI-1759 b, using photometric time series from Transiting Exoplanet Survey Satellite (TESS) near-infrared spectropolarimetric data Spectro-Polarimètre Infra Rouge (SPIRou) on Canada-France-Hawaii Telescope. b orbits a moderately active M0V star with an orbital period 18.849975 ± 0.000006 days, we measured planetary radius mass 3.06 0.22 R ⊕ 6.8 2.0 M . Radial velocities were extracted SPIRou spectra both cross-correlation...
We report the discovery of TOI-530b, a transiting giant planet around an M0.5V dwarf, delivered by Transiting Exoplanet Survey Satellite (TESS). The host star is located at distance $147.7\pm0.6$ pc with radius $R_{\ast}=0.54\pm0.03\ R_{\odot}$ and mass $M_{\ast}=0.53\pm0.02\ M_{\odot}$. verify planetary nature transit signals combining ground-based multi-wavelength photometry, high resolution spectroscopy from SPIRou as well high-angular-resolution imaging. With $V=15.4$ mag, TOI-530b...
We report the discovery of an ultrahot Jupiter with extremely short orbital period $0.67247414\,\pm\,0.00000028$ days ($\sim$16 hr). The $1.347 \pm 0.047$ $R_{\rm Jup}$ planet, initially identified by Transiting Exoplanet Survey Satellite (TESS) mission, orbits TOI-2109 (TIC 392476080): a $T_{\rm eff} \sim 6500$ K F-type star mass $1.447 0.077$ $M_{\rm Sun}$, radius $1.698 0.060$ and rotational velocity $v\sin i_* = 81.9 1.7$ km s$^{-1}$. planetary nature TOI-2109b was confirmed through...
Abstract Kepler 1627A is a G8V star previously known to host 3.8 R ⊕ planet on 7.2 day orbit. The was observed by the space telescope because it nearby ( d = 329 pc) and resembles Sun. Here, we show using Gaia kinematics, TESS stellar rotation periods, spectroscopic lithium abundances that 1627 member of <?CDATA ${38}_{-5}^{+6}$?> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msubsup> <mml:mrow> <mml:mn>38</mml:mn> </mml:mrow> <mml:mo>−</mml:mo>...
We present the discovery of two exoplanets transiting TOI-836 (TIC 440887364) using data from TESS Sector 11 and 38. is a bright ($T = 8.5$ mag), high proper motion ($\sim\,200$ mas yr$^{-1}$), low metallicity ([Fe/H]$\approx\,-0.28$) K-dwarf with mass $0.68\pm0.05$ M$_{\odot}$ radius $0.67\pm0.01$ R$_{\odot}$. obtain photometric follow-up observations variety facilities, we use these data-sets to determine that inner planet, b, $1.70\pm0.07$ R$_{\oplus}$ super-Earth in 3.82 day orbit,...
We present spatially resolved mass outflow rate measurements ($\dot M_{out}$) for the narrow line region of Markarian 34, nearest Compton-thick type 2 quasar (QSO2). Spectra obtained with Hubble Space Telescope and at Apache Point Observatory reveal complex kinematics, distinct signatures rotation within kpc nucleus. Using multi-component photoionization models, we find that contains a total ionized gas $M \approx 1.6 \times 10^6 M_{\odot}$. Combining this kinematics yields peak $\dot...
ABSTRACT We report the discovery of two warm sub-Neptunes transiting bright (G = 9.5 mag) K-dwarf HD 15906 (TOI 461, TIC 4646810). This star was observed by Transiting Exoplanet Survey Satellite (TESS) in sectors 4 and 31, revealing small planets. The inner planet, b, detected with an unambiguous period but outer c, showed only transits separated ∼ 734 d, leading to 36 possible values its period. performed follow-up observations CHaracterising ExOPlanet (CHEOPS) confirm true c improve radius...
Context. Thanks to the relative ease of finding and characterizing small planets around M-dwarf stars, these objects have become cornerstones in field exoplanet studies. The current paucity long-period orbits M dwarfs makes such particularly compelling as they provide clues about formation evolution systems. Aims. In this study we present discovery TOI-2257 b (TIC 198485881), a (35 d) sub-Neptune orbiting an M3 star at 57.8 pc. Its transit depth is 0.4%, large enough be detected with...
Abstract Close-in gas giants present a surprising range of stellar obliquity, the angle between planet’s orbital axis and its host star’s spin axis. It is unclear whether obliquities reflect planets’ dynamical history (e.g., aligned for in situ formation or disk migration versus misaligned high-eccentricity tidal migration) other mechanisms primordial misalignment planet–star interactions) are more important sculpting obliquity distribution. Here we measurement TOI-1268 (TIC-142394656, V mag...
ABSTRACT We present the discovery of TOI-2136 b, a sub-Neptune planet transiting nearby M4.5V-type star every 7.85 d, identified through photometric measurements from Transiting Exoplanet Survey Satellite (TESS) mission. The host is located 33 pc away with radius R* = 0.34 ± 0.02 R⊙, mass $0.34\pm \, \mathrm{M}_{\odot }$, and an effective temperature 3342 100 K. estimate its stellar rotation period to be 75 5 d based on archival long-term photometry. confirm characterize series ground-based...
We report the discovery and characterization of two small transiting planets orbiting bright M3.0V star TOI-1468 (LSPM J0106+1913), whose transit signals were detected in photometric time series three sectors TESS mission. confirm e planetary nature both them using precise radial velocity measurements from CARMENES MAROON-X spectrographs, supplement with ground-based photometry. A joint analysis all these data reveals that shorter-period planet, b ($P_{\rm b}$ = 1.88 d), has a mass $M_{\rm...
Abstract Roughly half of Solar-type planet hosts have stellar companions, so understanding how these binary companions affect the formation and evolution planets is an important component to planetary systems overall. Measuring dynamical properties host binaries enables a valuable test in multistar requires knowledge orbital parameters. Using high-resolution imaging, we measured relative astrometry visual orbits 13 where one stars known transiting exoplanet. Our results indicate that mutual...
Starting in 2008, NASA has provided the exoplanet community an observational program aimed at obtaining highest resolution imaging available as part of its mission to validate and characterize exoplanets, well their stellar environments, search life Universe. Our current uses speckle interferometry optical (320–1,000 nm) with new instruments on 3.5-m WIYN both 8-m Gemini telescopes. Kepler K2 follow-up, we now support TESS other space- ground-based related discovery characterization...
Abstract We report the discovery of TOI-4562b (TIC-349576261), a Jovian planet orbiting young F7V-type star, younger than Praesepe/Hyades clusters (<700 Myr). This stands out because its unusually long orbital period for transiting planets with known masses ( P orb = 225.11781 <?CDATA ${}_{-0.00022}^{+0.00025}$?> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msubsup> <mml:mrow /> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>0.00022</mml:mn> </mml:mrow>...