Alicia Kendall
A5037825116- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Astro and Planetary Science
- Astrophysics and Star Formation Studies
- Astronomical Observations and Instrumentation
- Gamma-ray bursts and supernovae
- Geophysics and Gravity Measurements
- History and Developments in Astronomy
- Photonic and Optical Devices
- Space Exploration and Technology
- Species Distribution and Climate Change
- Laser-Matter Interactions and Applications
- Advanced Fiber Laser Technologies
- Semiconductor Lasers and Optical Devices
University of Leicester
2022-2024
Queen's University Belfast
2022
University of Warwick
2022
Long-period transiting planets provide the opportunity to better understand formation and evolution of planetary systems. Their atmospheric properties remain largely unaltered by tidal or radiative effects host star, their orbital arrangement reflects a different, less extreme, migrational history compared close-in objects. The sample long-period exoplanets with well determined masses radii is still limited, but growing number objects reveal themselves in TESS data. Our goal vet confirm...
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,...
ABSTRACT We report the discovery of a brown dwarf orbiting M1 host star. first identified within Next Generation Transit Survey data, with supporting observations found in TESS sectors 11 and 38. confirmed follow-up photometry from South African Astronomical Observatory, SPECULOOS-S, TRAPPIST-S, radial velocity measurements HARPS, which allowed us to characterize system. find an orbital period ∼1.25 d, mass $69.0^{+5.3}_{-4.8}$ MJ, close hydrogen burning limit, radius 0.95 ± 0.05 RJ....
ABSTRACT We report the discovery of most eccentric transiting brown dwarf in desert, TOI-2490b. The desert is lack dwarfs around main-sequence stars within $\sim 3$ au and thought to be caused by differences formation mechanisms between a star planet. To date, only 40$ have been confirmed. TOI-2490b $73.6\pm 2.4$ $M_{\rm J}$, $1.00\pm 0.02$ $R_{\rm J}$ orbiting $1.004_{-0.022}^{+0.031}$ ${\rm M}_{\odot }$, $1.105_{-0.012}^{+0.012}$ R}_{\odot }$ sun-like on 60.33 d orbit with an eccentricity...
ABSTRACT We report the discovery of three new hot Jupiters with Next Generation Transit Survey (NGTS) as well updated parameters for HATS-54b, which was independently discovered by NGTS. NGTS-23b, NGTS-24b, and NGTS-25b have orbital periods 4.076, 3.468, 2.823 d orbit G-, F-, K-type stars, respectively. NGTS-24 HATS-54 appear close to transitioning off main-sequence (if they are not already doing so), therefore interesting targets given observed lack around sub-giant stars. By considering...
Long-period transiting exoplanets bridge the gap between bulk of transit- and Doppler-based exoplanet discoveries, providing key insights into formation evolution planetary systems. The wider separation these planets their host stars results in typically experiencing less radiation from stars; hence, they should maintain more original atmospheres, which can be probed during transit via transmission spectroscopy. Although known population long-period is relatively sparse, surveys performed by...
Discovering transiting exoplanets with relatively long orbital periods ($>$10 days) is crucial to facilitate the study of cool exoplanet atmospheres ($T_{\rm eq} < 700 K$) and understand formation inward migration further out than typical exoplanets. In order discover these longer period exoplanets, long-term photometric radial velocity campaigns are required. We report discovery TOI-2447 b ($=$ NGTS-29b), a Saturn-mass orbiting bright (T=10.0) Solar-type star (T$_{\rm eff}$=5730 K). was...
ABSTRACT Transiting exoplanets orbiting young nearby stars are ideal laboratories for testing theories of planet formation and evolution. However, to date only a handful with age &lt;1 Gyr have been found host transiting exoplanets. Here we present the discovery validation sub-Neptune around HD 18599 , (300 Myr), (d = 40 pc) K star. We validate candidate as bona fide using data from TESS Spitzer Gaia missions, ground-based photometry IRSF LCO PEST NGTS speckle imaging Gemini,...
We report the discovery of a 1.32$^{+0.10}_{-0.10}$ $\mathrm{M_{\rm Jup}}$ planet orbiting on 75.12 day period around G3V $10.8^{+2.1}_{-3.6}$ Gyr old star TOI-5542 (TIC 466206508; TYC 9086-1210-1). The was first detected by Transiting Exoplanet Survey Satellite (TESS) as single transit event in TESS Sector 13. A second observed 376 days later 27. planetary nature object has been confirmed ground-based spectroscopic and radial velocity observations from CORALIE HARPS spectrographs. third...
ABSTRACT The dipper is a novel class of young stellar object associated with large drops in flux on the order 10–50 per cent lasting for hours to days. Too significant arise from intrinsic variability, these are currently attributed disc warps, accretion streams, and/or transiting circumstellar dust. Dippers have been previously studied star-forming regions, including Orion Complex. Using Next Generation Transit Survey (NGTS) data, we identified variable stars their light curves. We then...
We report the discovery of a brown dwarf orbiting M1 host star. first identified within Next Generation Transit Survey data, with supporting observations found in TESS sectors 11 and 38. confirmed follow-up photometry from South African Astronomical Observatory, SPECULOOS-S, TRAPPIST-S, radial velocity measurements HARPS, which allowed us to characterise system. find an orbital period ~1.25 d, mass 69.0+5.3-4.8 MJ, close Hydrogen burning limit, radius 0.95 +- 0.05 RJ. determine age be >0.5...
Context . Long-period transiting exoplanets bridge the gap between bulk of transit- and Doppler-based exoplanet discoveries, providing key insights into formation evolution planetary systems. The wider separation these planets their host stars results in typically experiencing less radiation from stars; hence, they should maintain more original atmospheres, which can be probed during transit via transmission spectroscopy. Although known population long-period is relatively sparse, surveys...
Abstract We present the results from first two years of Planet Hunters Next Generation Transit Survey (NGTS) citizen science project, which searches for transiting planet candidates in data NGTS by enlisting help members general public. Over 8000 registered volunteers reviewed 138,198 light curves Public Data Releases 1 and 2. utilize a user weighting scheme to combine classifications multiple users identify most promising not initially discovered team. highlight five interesting detected...
We present the results from first two years of Planet Hunters NGTS citizen science project, which searches for transiting planet candidates in data Next Generation Transit Survey (NGTS) by enlisting help members general public. Over 8,000 registered volunteers reviewed 138,198 light curves Public Data Releases 1 and 2. utilize a user weighting scheme to combine classifications multiple users identify most promising not initially discovered team. highlight five interesting detected through...
The TOI-178 system consists of a nearby late K-dwarf transited by six planets in the super-Earth to mini-Neptune regime, with radii ranging from 1.2 2.9 earth radius and orbital periods between 1.9 20.7 days. All but innermost one form chain Laplace resonances. fine-tuning fragility such configurations ensure that no significant scattering or collision event has taken place since formation migration protoplanetary disc, hence providing important anchors for planet models. We aim improve...
Context . The TOI-178 system consists of a nearby, late-K-dwarf with six transiting planets in the super-Earth to mini-Neptune regime, radii ranging from 2.9 R ⊕ and orbital periods between 1.9 20.7 days. All planets, but innermost one, form chain Laplace resonances. fine-tuning fragility such configurations ensure that no significant scattering or collision event has taken place since formation migration protoplanetary disc, thereby providing important anchors for planet models. Aims We aim...
ABSTRACT Discovering transiting exoplanets with relatively long orbital periods (&gt;10 d) is crucial to facilitate the study of cool exoplanet atmospheres (Teq &lt; 700 K) and understand formation inward migration further out than typical exoplanets. In order discover these longer period exoplanets, long-term photometric, radial velocity campaigns are required. We report discovery TOI-2447 b (=NGTS-29 b), a Saturn-mass orbiting bright (T = 10.0) Solar-type star (Teff 5730 K). was...
We report the discovery of most eccentric transiting brown dwarf in desert, TOI02490b. The desert is lack dwarfs around main sequence stars within $\sim3$~AU and thought to be caused by differences formation mechanisms between a star planet. To date, only $\sim40$ have been confirmed. \systemt $73.6\pm2.4$ \mjupnospace, $1.00\pm0.02$ \rjup orbiting $1.004_{-0.022}^{+0.031}$ \msunnospace, $1.105_{-0.012}^{+0.012}$ \rsun sun-like on 60.33~d orbit with an eccentricity $0.77989\pm0.00049$. was...
In the last few decades planet search surveys have been focusing on solar type stars, and only recently high-mass regimes. This is mostly due to challenges arising from lack of instrumental precision, more importantly, inherent active nature fast rotating massive stars. Here we report NGTS-33b (TOI-6442b), a super-Jupiter with mass, radius orbital period 3.6 $\pm$ 0.3 M$_{\rm jup}$, 1.64 0.07 R$_{\rm jup}$ $2.827972 \pm 0.000001$ days, respectively. The host ($0.6654 0.0006$ day) hot...
Abstract In the last few decades planet search surveys have been focusing on solar type stars, and only recently high-mass regimes. This is mostly due to challenges arising from lack of instrumental precision, more importantly, inherent active nature fast rotating massive stars. Here we report NGTS-33b (TOI-6442b), a super-Jupiter with mass, radius orbital period 3.6 ± 0.3 Mj, 1.64 0.07 Rj 2.827972 0.000001 days, respectively. The host (0.6654 0.0006 day) hot (Teff = 7437 72 K) A9V star,...
Abstract We present the discoveries of NGTS-31b(=TOI-2721), and NGTS-32b, two hot Jupiters from Next Generation Transit Survey (NGTS) transiting slightly evolved stars. The orbital periods, radii, masses are 4.16 3.31 days, 1.61 1.42 Rj, 1.12 0.57 Mj, respectively. Both planets have an incident stellar flux significantly above threshold where inflation occurs, with both showing signs inflation. These widely different equilibrium temperatures than other similar mass radius, NGTS-32a having a...
ABSTRACT Despite being the most common types of stars in Galaxy, physical properties late M dwarfs are often poorly constrained. A trend radius inflation compared to evolutionary models has been observed for earlier type eclipsing binaries, possibly caused by magnetic activity. It is currently unclear whether this also extends later below convective boundary. This makes discovery lower mass, fully convective, binaries valuable testing – especially longer-period where tidal interaction...
The Next Generation Transit Survey (NGTS) has now been operating for six years, discovering and characterizing transiting exoplanets around bright stars. We outline the NGTS project, including Andor CCD cameras used to perform high-precision time-series photometry. quantify photometric precision a sample of over 20,000 star observations. find single telescope observations we achieve 30-minute 400 ppm at low airmass. This is in good agreement with noise predicted using four-component model....
We report the discovery of NGTS-21b, a massive hot Jupiter orbiting low-mass star as part Next Generation Transit Survey (NGTS). The planet has mass and radius $2.36 \pm 0.21$ M$_{\rm J}$, $1.33 0.03$ R$_{\rm an orbital period 1.543 days. host is K3V ($T_{\rm eff}=4660 41$, K) metal-poor (${\rm [Fe/H]}=-0.26 0.07$, dex) dwarf with $0.72 0.04$, M$_{\odot}$,and $0.86 R$_{\odot}$. Its age rotation $10.02^{+3.29}_{-7.30}$, Gyr $17.88 0.08$, d respectively, are in accordance observed moderately...
We present a study of rotation across 30 square degrees the Orion Star-forming Complex, following $\sim$200 d photometric monitoring campaign by Next Generation Transit Survey (NGTS). From 5749 light curves members, we report periodic signatures for 2268 objects and analyse period distributions as function colour 1789 stars with spectral types F0$-$M5. select candidate members using $\textit{Gaia}$ data assign our targets to kinematic sub-groups. correct interstellar extinction on...