papers

Publications (109)

astro-ph.EP2022

Atmospheric processes affecting methane on Mars

John Lee Grenfell, Fabian Wunderlich, Miriam Sinnhuber +6

It is currently uncertain as to whether methane exists on Mars. Data from the Curiosity Rover suggests a background methane concentration of a few tenths parts per billion whereas…

astro-ph.EP2019

The habitability of stagnant-lid Earths around dwarf stars

Mareike Godolt, Nicola Tosi, Barbara Stracke +4

The habitability of a planet depends on various factors, such as delivery of water during the formation, the co-evolution of the interior and the atmosphere, as well as the stellar…

astro-ph.EP2017

Exoplanet Biosignatures: Understanding Oxygen as a Biosignature in the Context of Its Environment

Victoria S. Meadows, Christopher T. Reinhard, Giada N. Arney +13

Here we review how environmental context can be used to interpret whether O2 is a biosignature in extrasolar planetary observations. This paper builds on the overview of current bi…

astro-ph.EP2018

Exoplanets around Low-mass Stars Unveiled by K2

Teruyuki Hirano, Fei Dai, Davide Gandolfi +38

We present the detection and follow-up observations of planetary candidates around low-mass stars observed by the K2 mission. Based on light-curve analysis, adaptive-optics imaging…

astro-ph.EP2019

K2-264: A transiting multi-planet system in the Praesepe open cluster

John H. Livingston, Fei Dai, Teruyuki Hirano +31

Planet host stars with well-constrained ages provide a rare window to the time domain of planet formation and evolution. The NASA K2 mission has enabled the discovery of the vast m…

astro-ph.EP2017

Probing the atmosphere of a sub-Jovian planet orbiting a cool dwarf

Elyar Sedaghati, Henri. M. J. Boffin, Laetitia Delrez +4

We derive the 0.01 m binned transmission spectrum, between 0.74 and 1.0 m, of WASP-80b from low resolution spectra obtained with the FORS2 instrument attached to ESO's Very…

astro-ph.EP2011

On the Mass of CoRoT-7b

Artie P. Hatzes, Malcolm Fridlund, Gil Nachmani +25

The mass of CoRoT-7b, the first transiting superearth exoplanet, is still a subject of debate. A wide range of masses have been reported in the literature ranging from as high as 8…

astro-ph.EP2021

Possible Atmospheric Diversity of Low Mass Exoplanets, some Central Aspects

John Lee Grenfell, Jeremy Leconte, François Forget +9

Exoplanetary science continues to excite and surprise with its rich diversity. We discuss here some key aspects potentially influencing the range of exoplanetary terrestrial-type a…

astro-ph.EP2019

NGTS-8b and NGTS-9b: two non-inflated hot-Jupiters

Jean C. Costes, Christopher A. Watson, Claudia Belardi +35

We report the discovery, by the Next Generation Transit Survey (NGTS), of two hot-Jupiters NGTS-8b and NGTS-9b. These orbit a V = 13.68 K0V star (Teff = 5241 +/- 50 K) with a perio…

astro-ph.EP2020

Directly imaged exoplanets in reflected starlight. The importance of knowing the planet radius

Óscar Carrión-González, Antonio García Muñoz, Juan Cabrera +3

We have investigated the information content in reflected-starlight spectra of exoplanets. We specify our analysis to Barnard's Star b candidate super-Earth, for which we assume a…

astro-ph.EP2021

GJ 367b: A dense ultra-short period sub-Earth planet transiting a nearby red dwarf star

Kristine W. F. Lam, Szilárd Csizmadia, Nicola Astudillo-Defru +75

Ultra-short-period (USP) exoplanets have orbital periods shorter than one day. Precise masses and radii of USPs could provide constraints on their unknown formation and evolution p…

astro-ph.EP2019

A New Model Suite to Determine the Influence of Cosmic Rays on (Exo)planetary Atmospheric Biosignatures -- Validation based on Modern Earth

Konstantin Herbst, John Lee Grenfell, Miriam Sinnhuber +8

The first opportunity to detect indications for life outside the Solar System may be provided already within the next decade with upcoming missions such as the James Webb Space Tel…

astro-ph.EP2018

Three Small Planets Transiting a Hyades Star

John H. Livingston, Fei Dai, Teruyuki Hirano +33

We present the discovery of three small planets transiting K2-136 (LP 358 348, EPIC 247589423), a late K dwarf in the Hyades. The planets have orbital periods of $7.9757 \pm 0.0011…

astro-ph.EP2013

Photophoretic separation of metals and silicates: the formation of Mercury like planets and metal depletion in chondrites

Gerhard Wurm, Mario Trieloff, Heike Rauer

Mercury's high uncompressed mass density suggests that the planet is largely composed of iron, either bound within metal (mainly Fe-Ni), or iron sulfide. Recent results from the ME…

astro-ph.EP2020

Effect of mantle oxidation state and escape upon the evolution of Earth's magma ocean atmosphere

Nisha Katyal, Gianluigi Ortenzi, John Lee Grenfell +7

The magma ocean period was a critical phase determining how Earth atmosphere developed into habitability. However there are major uncertainties in the role of key processes such as…

astro-ph.EP2017

The Next Generation Transit Survey (NGTS)

Peter J. Wheatley, Richard G. West, Michael R. Goad +43

We describe the Next Generation Transit Survey (NGTS), which is a ground-based project searching for transiting exoplanets orbiting bright stars. NGTS builds on the legacy of previ…

astro-ph2007

Biomarker Response to Galactic Cosmic Ray-Induced NOx and the Methane Greenhouse Effect in the Atmosphere of an Earthlike Planet Orbiting an M-Dwarf Star

John Lee Grenfell, Jean-Mathias Griessmeier, Beate Patzer +6

Planets orbiting in the habitable zone (HZ) of M-Dwarf stars are subject to high levels of galactic cosmic rays (GCRs) which produce nitrogen oxides in earthlike atmospheres. We in…

astro-ph.EP2021

Transit detection of the long-period volatile-rich super-Earth Lupi d with

Laetitia Delrez, David Ehrenreich, Yann Alibert +75

Exoplanets transiting bright nearby stars are key objects for advancing our knowledge of planetary formation and evolution. The wealth of photons from the host star gives detailed…

astro-ph.EP2019

What factors affect the duration and outgassing of the terrestrial magma ocean?

Athanasia Nikolaou, Nisha Katyal, Nicola Tosi +3

The magma ocean (MO) is a crucial stage in the build-up of terrestrial planets. Its solidification and the accompanying outgassing of volatiles set the conditions for important pro…

astro-ph.EP2017

Detection of titanium oxide in the atmosphere of a hot Jupiter

Elyar Sedaghati, Henri M. J. Boffin, Ryan J. MacDonald +6

As an exoplanet transits its host star, some of the light from the star is absorbed by the atoms and molecules in the planet's atmosphere, causing the planet to seem bigger; plotti…

astro-ph.EP2016

K2-60b and epic 216468514b. A sub-jovian and a jovian planet from the k2 mission

Philipp Eigmüller, Davide Gandolfi, Carina M. Persson +20

We report the characterization and independant detection of K2-60b, as well as the detection and characterization of EPIC 216468514b, two transiting hot gaseous planets from the K2…

astro-ph2006

The Response of Atmospheric Chemistry on Earthlike Planets around F, G and K Stars to Small Variations in Orbital Distance

John Lee Grenfell, Barbara Stracke, Philip von Paris +4

One of the prime goals of future investigations of extrasolar planets is to search for life as we know it. The Earth's biosphere is adapted to current conditions. How would the atm…

astro-ph2008

Prospects of long-time-series observations from Dome C for transit search

Heike Rauer, Thomas Fruth, Anders Erikson

The detection of transiting extrasolar planets requires high-photometric quality and long-duration photometric stellar time-series. In this paper, we investigate the advantages pro…

astro-ph.EP2023

TESS and CHEOPS Discover Two Warm Sub-Neptunes Transiting the Bright K-dwarf HD 15906

Amy Tuson, Didier Queloz, Hugh P. Osborn +119

We report the discovery of two warm sub-Neptunes transiting the bright (G = 9.5 mag) K-dwarf HD 15906 (TOI 461, TIC 4646810). This star was observed by the Transiting Exoplanet Sur…

astro-ph.EP2021

Atmospheric characterization of terrestrial exoplanets in the mid-infrared: biosignatures, habitability & diversity

Sascha P. Quanz, Olivier Absil, Daniel Angerhausen +45

Exoplanet science is one of the most thriving fields of modern astrophysics. A major goal is the atmospheric characterization of dozens of small, terrestrial exoplanets in order to…

astro-ph.EP2010

The SARS algorithm: detrending CoRoT light curves with Sysrem using simultaneous external parameters

Aviv Ofir, Roi Alonso, Aldo Stefano Bonomo +31

Surveys for exoplanetary transits are usually limited not by photon noise but rather by the amount of red noise in their data. In particular, although the CoRoT spacebased survey d…

astro-ph.EP2021

Unveiling shrouded oceans on temperate sub-Neptunes via transit signatures of solubility equilibria vs. gas thermochemistry

Renyu Hu, Mario Damiano, Markus Scheucher +3

The recent discovery and initial characterization of sub-Neptune-sized exoplanets that receive stellar irradiance of approximately Earth's raised the prospect of finding habitable…

astro-ph2006

Potential of Ozone Formation by the Smog Mechanism to shield the surface of the Early Earth from UV radiation?

John Lee Grenfell, Barbara Stracke, Beate Patzer +2

We propose that the photochemical smog mechanism produced substantial ozone (O3) in the troposphere during the Proterozoic, which contributed to ultraviolet (UV) radiation shieldin…

astro-ph.EP2024

Large Interferometer For Exoplanets (LIFE). XIV. Finding terrestrial protoplanets in the galactic neighborhood

Lorenzo Cesario, Tim Lichtenberg, Eleonora Alei +62

The increased brightness temperature of young rocky protoplanets during their magma ocean epoch makes them potentially amenable to atmospheric characterization to distances from th…

astro-ph.EP2020

Detectability of biosignatures on LHS 1140 b

Fabian Wunderlich, Markus Scheucher, John Lee Grenfell +4

Terrestrial extrasolar planets around low-mass stars are prime targets when searching for atmospheric biosignatures with current and near-future telescopes. The habitable-zone Supe…

astro-ph.EP2017

The transiting multi-planet system HD3167: a 5.7 MEarth Super-Earth and a 8.3 MEarth mini-Neptune

Davide Gandolfi, Oscar Barragán, Artie P. Hatzes +42

HD3167 is a bright (V=8.9 mag) K0V star observed by the NASA's K2 space mission during its Campaign 8. It has been recently found to host two small transiting planets, namely, HD31…

astro-ph.EP2020

NGTS-11 b / TOI-1847 b: A transiting warm Saturn recovered from a TESS single-transit event

Samuel Gill, Peter J. Wheatley, Benjamin F. Cooke +37

We report the discovery of NGTS-11 b (=TOI-1847 b), a transiting Saturn in a 35.46-day orbit around a mid K-type star (Teff=5050 K). We initially identified the system from a singl…

astro-ph.EP2019

Evolution and Spectral Response of a Steam Atmosphere for Early Earth with a coupled climate-interior model

Nisha Katyal, Athanasia Nikolaou, Mareike Godolt +4

The evolution of Earth's early atmosphere and the emergence of habitable conditions on our planet are intricately coupled with the development and duration of the magma ocean phase…

astro-ph.EP2017

Centroid vetting of transiting planet candidates from the Next Generation Transit Survey

Maximilian N. Günther, Didier Queloz, Edward Gillen +25

The Next Generation Transit Survey (NGTS), operating in Paranal since 2016, is a wide-field survey to detect Neptunes and super-Earths transiting bright stars, which are suitable f…

astro-ph.EP2022

TOI-836: A super-Earth and mini-Neptune transiting a nearby K-dwarf

Faith Hawthorn, Daniel Bayliss, Thomas G. Wilson +137

We present the discovery of two exoplanets transiting TOI-836 (TIC 440887364) using data from TESS Sector 11 and Sector 38. TOI-836 is a bright ( mag), high proper motion…

astro-ph.EP2020

Shallow transit follow-up from NGTS: simultaneous observations of HD106315 with 11 identical telescopes

Alexis M. S. Smith, Philipp Eigmüller, Ramanathan Gurumoorthy +15

The Next Generation Transit Survey (NGTS) is a photometric survey for transiting exoplanets, consisting of twelve identical 0.2-m telescopes. We report a measurement of the transit…

astro-ph.EP2021

Catalogue of exoplanets accessible in reflected starlight to the Nancy Grace Roman Space Telescope. A population study and prospects for phase-curve measurements

Óscar Carrión-González, Antonio García Muñoz, Juan Cabrera +3

Reflected starlight measurements will open a new path in the characterization of directly imaged exoplanets. However, we still lack a population study of known targets amenable to…

astro-ph.IM2020

The CHEOPS mission

Willy Benz, Christopher Broeg, Andrea Fortier +107

The CHaracterising ExOPlanet Satellite (CHEOPS) was selected in 2012, as the first small mission in the ESA Science Programme and successfully launched in December 2019. CHEOPS is…

astro-ph.IM2009

ASTEP South: An Antarctic Search for Transiting ExoPlanets around the celestial South pole

Nicolas Crouzet, Tristan Guillot, Karim Agabi +19

ASTEP South is the first phase of the ASTEP project (Antarctic Search for Transiting ExoPlanets). The instrument is a fixed 10 cm refractor with a 4kx4k CCD camera in a thermalized…

astro-ph.EP2026

An Ultra-Short Period Super-Earth and a Sub-Neptune Orbiting the K dwarf TOI-4311

Yoshi Nike Emilia Eschen, Thomas G. Wilson, Andrew Collier Cameron +95

We report the discovery and characterisation of the multi-planetary system around TOI-4311, a K dwarf kinematically between the Galactic thick disk and Hercules stream. TOI-4311 ho…

astro-ph2007

Dynamical modeling of the Deep Impact dust ejecta cloud

Tanyu Bonev, Nancy Ageorges, Stefano Bagnulo +17

The collision of Deep Impact with comet 9P/Tempel 1 generated a bright cloud of dust which dissipated during several days after the impact. The brightness variations of this cloud…

astro-ph.EP2020

NGTS-10b: The shortest period hot Jupiter yet discovered

James McCormac, Edward Gillen, James A. G. Jackman +44

We report the discovery of a new ultra-short period transiting hot Jupiter from the Next Generation Transit Survey (NGTS). NGTS-10b has a mass and radius of $2.162\,^{+0.092}_{-0.1…

astro-ph.EP2017

EPIC 210894022b - A short period super-Earth transiting a metal poor, evolved old star

Malcolm Fridlund, Eric Gaidos, Oscar Barragán +31

The star EPIC 210894022 has been identified from a light curve acquired through the K2 space mission as possibly orbited by a transiting planet. Our aim is to confirm the planetary…

astro-ph.EP2022

Uncovering the true periods of the young sub-Neptunes orbiting TOI-2076

Hugh P. Osborn, Andrea Bonfanti, Davide Gandolfi +93

Context: TOI-2076 is a transiting three-planet system of sub-Neptunes orbiting a bright (G = 8.9 mag), young ( Myr) K-type star. Although a validated planetary system, th…

astro-ph.SR2026

The PLATO Science Calibration and Validation Plan: Targets for the First Long-pointing Field

Konstanze Zwintz, Conny Aerts, Andrew Tkachenko +56

In order to meet the science goals of the PLATO space mission, an extensive science calibration and validation plan has been designed. This paper describes this plan, as well as th…

astro-ph.EP2020

The multi-planet system TOI-421 -- A warm Neptune and a super puffy mini-Neptune transiting a G9 V star in a visual binary

Ilaria Carleo, Davide Gandolfi, Oscar Barragán +110

We report the discovery of a warm Neptune and a hot sub-Neptune transiting TOI-421 (BD-14 1137, TIC 94986319), a bright (V=9.9) G9 dwarf star in a visual binary system observed by…

astro-ph.EP2019

HST/STIS capability for Love number measurement of WASP-121b

Hugo Hellard, Szilárd Csizmadia, Sebastiano Padovan +2

Data from transit light curves, radial velocity and transit timing observations can be used to probe the interiors of exoplanets beyond the mean density, by measuring the Love numb…

astro-ph.EP2022

A pair of Sub-Neptunes transiting the bright K-dwarf TOI-1064 characterised with CHEOPS

Thomas G. Wilson, Elisa Goffo, Yann Alibert +132

We report the discovery and characterisation of a pair of sub-Neptunes transiting the bright K-dwarf TOI-1064 (TIC 79748331), initially detected in TESS photometry. To characterise…

astro-ph.EP2019

NGTS-6b: An Ultra Short Period Hot-Jupiter Orbiting an Old K Dwarf

Jose I. Vines, James S. Jenkins, Jack S. Acton +37

We report the discovery of a new ultra-short period hot Jupiter from the Next Generation Transit Survey. NGTS-6b orbits its star with a period of 21.17~h, and has a mass and radius…

astro-ph.EP2019

The Transiting Multi-planet System HD15337: Two Nearly Equal-mass Planets Straddling the Radius Gap

Davide Gandolfi, Luca Fossati, John H. Livingston +53

We report the discovery of a super-Earth and a sub-Neptune transiting the star HD 15337 (TOI-402, TIC 120896927), a bright (V=9) K1 dwarf observed by the Transiting Exoplanet Surve…

astro-ph.EP2012

Atmospheric constraints for the CO2 partial pressure on terrestrial planets near the outer edge of the habitable zone

Philip von Paris, J. Lee Grenfell, Pascal Hedelt +3

In recent years, several potentially habitable, probably terrestrial exoplanets and exoplanet candidates have been discovered. The amount of CO2 in their atmosphere is of great imp…

astro-ph.EP2010

Sensitivity of Biomarkers to Changes in Chemical Emissions in the Earth's Proterozoic Atmosphere

John Lee Grenfell, Stefanie Gebauer, Philip von Paris +5

The search for life beyond the Solar System is a major activity in exoplanet science. However, even if an Earth-like planet were to be found, it is unlikely to be at a similar stag…

astro-ph.EP2019

Is pi Men c's atmosphere hydrogen-dominated? Insights from a non-detecton of Hy Ly-alpha absorption

Antonio García Muñoz, Allison Youngblood, Luca Fossati +3

Constraining the composition of super-Earth-to-sub-Neptune-size planets is a priority to understand the processes of planetary formation and evolution. pi Men c represents a unique…

astro-ph.EP2024

In-situ observations of resident space objects with the CHEOPS space telescope

Nicolas Billot, Stephan Hellmich, Willy Benz +80

The CHaracterising ExOPlanet Satellite (CHEOPS) is a partnership between the European Space Agency and Switzerland with important contributions by 10 additional ESA member States.…

astro-ph.EP2020

Atmospheric Characterization via Broadband Color Filters on the PLAnetary Transits and Oscillations of stars (PLATO) Mission

John Lee Grenfell, Mareike Godolt, Juan Cabrera +5

We assess broadband color filters for the two fast cameras on the PLAnetary Transits and Oscillations (PLATO) of stars space mission with respect to exoplanetary atmospheric charac…

astro-ph.SR2020

TOI-503: The first known brown dwarf-Am star binary from the TESS mission

Ján Šubjak, Rishikesh Sharma, Theron W. Carmichael +76

We report the discovery of an intermediate-mass transiting brown dwarf, TOI-503b, from the TESS mission. TOI-503b is the first brown dwarf discovered by TESS and orbits a metallic-…

astro-ph.EP2021

Influence of Biomass Emissions upon Habitability, Biosignatures and Detectability in Earth-like Atmospheres

Stefanie Gebauer, Iva Vilović, John Lee Grenfell +3

We investigate atmospheric responses of modeled hypothetical Earth-like planets in the habitable zone of the M-dwarf AD Leonis to reduced oxygen (O2), removed biomass (dead Earth),…

astro-ph.EP2026

Assessment of PLATO Science Performance

Juan Cabrera, Heike Rauer, Reza Samadi +121

The PLATO mission is scheduled for launch early 2027. In this paper we present an overview of the performance drivers for the mission at the time where all flight models of the cam…

astro-ph.EP2025

An Ultra-Short Period Super-Earth and Sub-Neptune Spanning the Radius Valley Orbiting the Kinematic Thick Disk Star TOI-2345

Yoshi Nike Emilia Eschen, Thomas G. Wilson, Andrea Bonfanti +94

A crucial chemical link between stars and their orbiting exoplanets is thought to exist. If universal, this connection could affect the formation and evolution of all planets. Ther…

astro-ph.EP2024

PLATO's signal and noise budget

Anko Börner, Carsten Paproth, Juan Cabrera +20

ESA's PLATO mission aims the detection and characterization of terrestrial planets around solar-type stars as well as the study of host star properties. The noise-to-signal ratio (…

astro-ph.EP2010

Oxidation of CO on surface hematite in high CO2 atmospheres

John Lee Grenfell, Joachim W. Stock, A. Beate C. Patzer +2

We propose a mechanism for the oxidation of gaseous CO into CO2 occurring on the surface mineral hematite (Fe2O3(s)) in hot, CO2-rich planetary atmospheres, such as Venus. This mec…

astro-ph.EP2018

K2-155: A Bright Metal-Poor M Dwarf with Three Transiting Super-Earths

Teruyuki Hirano, Fei Dai, John H. Livingston +32

We report on the discovery of three transiting super-Earths around K2-155 (EPIC 210897587), a relatively bright early M dwarf ( mag) observed during Campaign 13 of the NAS…

astro-ph.EP2013

Spectral features of Earth-like planets and their detectability at different orbital distances around F, G, and K-type stars

Pascal Hedelt, Philip von Paris, Mareike Godolt +6

We investigate the spectral appearance of Earth-like exoplanets in the HZ of different main sequence stars at different orbital distances. We furthermore discuss for which of these…

astro-ph2006

Results from the Exoplanet Search Programmes with BEST and TEST

Jochen Eisloeffel, Artie P. Hatzes, Heike Rauer +4

Thueringer Landessternwarte Tautenburg (TLS) has started to operate a small dedicated telescope - the Tautenburg Exoplanet Search Telescope (TEST) - searching for transits of extra…

astro-ph.EP2019

Geoscience for understanding habitability in the solar system and beyond

Veronique Dehant, Vinciane Debaille, Vera Dobos +15

This paper reviews habitability conditions for a terrestrial planet from the point of view of geosciences. It addresses how interactions between the interior of a planet or a moon…

astro-ph.EP2020

K2-280b -- a low density warm sub-Saturn around a mildly evolved star

Grzegorz Nowak, Enric Palle, Davide Gandolfi +57

We present an independent discovery and detailed characterisation of K2-280b, a transiting low density warm sub-Saturn in a 19.9-day moderately eccentric orbit (e = 0.35_{-0.04}^{+…

astro-ph.EP2019

Greening of the Brown Dwarf Desert. EPIC 212036875 b -- a 51 M object in a 5 day orbit around an F7 V star

Carina M. Persson, Szilárd Csizmadia, Alexander J. Mustill +55

Our aim is to investigate the nature and formation of brown dwarfs by adding a new well-characterised object to the small sample of less than 20 transiting brown dwarfs. One brown…

astro-ph.EP2025

Characterizing WASP-43b's interior structure: unveiling tidal decay and apsidal motion

Lia Marta Bernabò, Szilárd Csizmadia, Alexis M. S. Smith +8

Context. Recent developments in exoplanetary research highlight the importance of Love numbers in understanding their internal dynamics, formation, migration history and their pote…

astro-ph.EP2018

44 Validated Planets from K2 Campaign 10

John H. Livingston, Michael Endl, Fei Dai +31

We present 44 validated planets from the 10 observing campaign of the NASA mission, as well as high resolution spectroscopy and speckle imaging follow-up observa…

astro-ph.EP2020

Distinguishing between wet and dry atmospheres of TRAPPIST-1 e and f

Fabian Wunderlich, Markus Scheucher, Mareike Godolt +7

The nearby TRAPPIST-1 planetary system is an exciting target for characterizing the atmospheres of terrestrial planets. The planets e, f and g lie in the circumstellar habitable zo…

astro-ph.EP2011

Spitzer Infrared Observations and Independent Validation of the Transiting Super-Earth CoRoT-7b

Francois Fressin, Guillermo Torres, Frederic Pont +8

The detection and characterization of the first transiting super-Earth, CoRoT-7 b, has required an unprecedented effort in terms of telescope time and analysis. Although the star d…

astro-ph.EP2018

Exoplanet Biosignatures: Observational Prospects

Yuka Fujii, Daniel Angerhausen, Russell Deitrick +9

Exoplanet hunting efforts have revealed the prevalence of exotic worlds with diverse properties, including Earth-sized bodies, which has fueled our endeavor to search for life beyo…

astro-ph.EP2018

NGTS-4b: A sub-Neptune Transiting in the Desert

Richard G. West, Edward Gillen, Daniel Bayliss +48

We report the discovery of NGTS-4b, a sub-Neptune-sized planet transiting a 13th magnitude K-dwarf in a 1.34d orbit. NGTS-4b has a mass M=M_E and radius R=

astro-ph.EP2026

Gas-depleted planet formation occurred in the four-planet system around the red dwarf LHS 1903

Thomas G. Wilson, Anna M. Simpson, Andrew Collier Cameron +173

Small exoplanet radii show two populations, referred to as super-Earths and sub-Neptunes, separated by a gap known as the radius valley. This may be produced by the removal of atmo…

astro-ph.EP2015

Sensitivity of Biosignatures on Earth-like Planets orbiting in the Habitable Zone of Cool M-Dwarf Stars to varying Stellar UV Radiation and Surface Biomass Emissions

John Lee Grenfell, Stefanie Gebauer, Philip von Paris +2

We find that variations in the UV emissions of cool M-dwarf stars have a potentially large impact upon atmospheric biosignatures in simulations of Earth-like exoplanets i.e. planet…

astro-ph.EP2020

An Ultra-Hot Neptune in the Neptune desert

James S. Jenkins, Matías R. Díaz, Nicolás T. Kurtovic +81

About one out of 200 Sun-like stars has a planet with an orbital period shorter than one day: an ultra-short-period planet (Sanchis-ojeda et al. 2014; Winn et al. 2018). All of the…

astro-ph.EP2019

NGTS-5b: a highly inflated planet offering insights into the sub-Jovian desert

Philipp Eigmüller, Alexander Chaushev, Edward Gillen +32

Context: Planetary population analysis gives us insight into formation and evolution processes. For short-period planets, the subJovian desert has been discussed in recent years wi…

astro-ph.EP2018

Automatic vetting of planet candidates from ground based surveys: Machine learning with NGTS

David J. Armstrong, Maximilian N. Günther, James McCormac +22

State of the art exoplanet transit surveys are producing ever increasing quantities of data. To make the best use of this resource, in detecting interesting planetary systems or in…

astro-ph.EP2014

Earth-like Habitats in Planetary Systems

Jörg Fritz, Bertram Bitsch, Ekkehard Kührt +8

Understanding the concept of habitability is related to an evolutionary knowledge of the particular planet-in-question. Additional indications so-called "systemic aspects" of the p…

astro-ph.EP2019

It takes two planets in resonance to tango around K2-146

Kristine W. F. Lam, Judith Korth, Kento Masuda +51

K2-146 is a cool, 0.358 M_sun dwarf that was found to host a mini-Neptune with a 2.67-days period. The planet exhibited strong transit timing variations (TTVs) of greater than 30 m…

astro-ph.EP2013

The Next Generation Transit Survey (NGTS)

Peter J. Wheatley, Don L. Pollacco, Didier Queloz +19

The Next Generation Transit Survey (NGTS) is a new ground-based sky survey designed to find transiting Neptunes and super-Earths. By covering at least sixteen times the sky area of…

astro-ph.EP2023

Two Warm Neptunes transiting HIP 9618 revealed by TESS & Cheops

Hugh P. Osborn, Grzegorz Nowak, Guillaume Hébrard +126

HIP 9618 (HD 12572, TOI-1471, TIC 306263608) is a bright ( mag) solar analogue. TESS photometry revealed the star to have two candidate planets with radii of

astro-ph.EP2018

NGTS-2b: An inflated hot-Jupiter transiting a bright F-dwarf

Liam Raynard, Michael R. Goad, Edward Gillen +42

We report the discovery of NGTS-2b, an inflated hot-Jupiter transiting a bright F5V star (2MASS J14202949-3112074; = K), discovered as part of the Ne…

astro-ph.EP2020

The effect of varying atmospheric pressure upon habitability and biosignatures of Earth-like planets

Engin Keles, John Lee Grenfell, Mareike Godolt +2

Understanding the possible climatic conditions on rocky extrasolar planets, and thereby their potential habitability, is one of the major subjects of exoplanet research. Determinin…

astro-ph.EP2016

Two Hot Jupiters from K2 Campaign 4

Marshall C. Johnson, Davide Gandolfi, Malcolm Fridlund +20

We confirm the planetary nature of two transiting hot Jupiters discovered by the Kepler spacecraft's K2 extended mission in its Campaign 4, using precise radial velocity measuremen…

astro-ph.EP2017

The discovery and mass measurement of a new ultra-short-period planet: EPIC~228732031b

Fei Dai, Joshua N. Winn, Davide Gandolfi +51

We report the discovery of a new ultra-short-period planet and summarize the properties of all such planets for which the mass and radius have been measured. The new planet, EPIC~2…

astro-ph.EP2016

Potassium detection in the clear atmosphere of a hot-Jupiter: FORS2 transmission spectroscopy of WASP-17b

Elyar Sedaghati, Henri M J Boffin, Tereza Jeřabková +9

We present FORS2 (attached to ESO's Very Large Telescope) observations of the exoplanet WASP-17b during its primary transit, for the purpose of differential spectrophotometry analy…

astro-ph.EP2024

Searching for GEMS: TOI-6383Ab, a giant planet transiting an M3-dwarf star in a binary system

Lia Marta Bernabò, Shubham Kanodia, Caleb I. Canas +22

We report on the discovery of a transiting giant planet around the 3500 K M3-dwarf star TOI-6383A located 172 pc from Earth. It was detected by the Transiting Exoplanet Survey Sate…

astro-ph.EP2018

Life Beyond the Solar System: Remotely Detectable Biosignatures

Shawn Domagal-Goldman, Nancy Y. Kiang, Niki Parenteau +38

For the first time in human history, we will soon be able to apply the scientific method to the question "Are We Alone?" The rapid advance of exoplanet discovery, planetary systems…

astro-ph.EP2016

EPIC 219388192 b - an inhabitant of the brown dwarf desert in the Ruprecht 147 open cluster

Grzegorz Nowak, Enric Palle, Davide Gandolfi +32

We report the discovery of EPIC 219388192 b, a transiting brown dwarf in a 5.3-day orbit around a member star of Ruprecht-147, the oldest nearby open cluster association, which was…

astro-ph.EP2024

Discovery of two warm mini-Neptunes with contrasting densities orbiting the young K3V star TOI-815

Angelica Psaridi, Hugh Osborn, François Bouchy +130

We present the discovery and characterization of two warm mini-Neptunes transiting the K3V star TOI-815 in a K-M binary system. Analysis of the spectra and rotation period reveal i…

astro-ph.EP2011

Spectroscopic characterization of the atmospheres of potentially habitable planets: GL 581 d as a model case study

Philip von Paris, Juan Cabrera, Mareike Godolt +5

(abridged) The Super-Earth candidate GL 581 d is the first potentially habitable extrasolar planet. Therefore, GL 581 d is used to illustrate a hypothetical detailed spectroscopic…

astro-ph.EP2021

Constraining the radius and atmospheric properties of directly imaged exoplanets through multi-phase observations

Óscar Carrión-González, Antonio García Muñoz, Nuno C. Santos +3

The theory of remote sensing shows that observing a planet at multiple phase angles () is a powerful strategy to characterize its atmosphere. Here, we analyse how the informati…

astro-ph.EP2020

NGTS-12b: A sub-Saturn mass transiting exoplanet in a 7.53 day orbit

Edward M. Bryant, Daniel Bayliss, Louise D. Nielsen +35

We report the discovery of the transiting exoplanet NGTS-12b by the Next Generation Transit Survey (NGTS). The host star, NGTS-12, is a V=12.38 mag star with an effective temperatu…

astro-ph.IM2024

The PLATO Mission

Heike Rauer, Conny Aerts, Juan Cabrera +842

PLATO (PLAnetary Transits and Oscillations of stars) is ESA's M3 mission designed to detect and characterise extrasolar planets and perform asteroseismic monitoring of a large numb…

astro-ph2004

Tidal interactions of close-in extrasolar planets: the OGLE cases

Martin Paetzold, Ludmila Carone, Heike Rauer

Close-in extrasolar planets experience extreme tidal interactions with their host stars. This may lead to a reduction of the planetary orbit and a spin-up of stellar rotation. Tida…

astro-ph.EP2017

NGTS-1b: A hot Jupiter transiting an M-dwarf

Daniel Bayliss, Edward Gillen, Philipp Eigmuller +40

We present the discovery of NGTS-1b, a hot-Jupiter transiting an early M-dwarf host () in a P=2.674d orbit discovered as part of the Next Generation Tra…

astro-ph.EP2015

Response of Atmospheric Biomarkers to NOx-induced Photochemistry Generated by Stellar Cosmic Rays for Earth-like Planets in the Habitable Zone of M-Dwarf Stars

John Lee Grenfell, Jean-Mathias Grriessmeier, Philip von Paris +6

Understanding whether M-dwarf stars may host habitable planets with Earth-like atmospheres and biospheres is a major goal in exoplanet research. If such planets exist, the question…

astro-ph.EP2019

In situ Exploration of the Giant Planets

Olivier Mousis, David H. Atkinson, Richard Ambrosi +27

Remote sensing observations suffer significant limitations when used to study the bulk atmospheric composition of the giant planets of our solar system. This impacts our knowledge…

astro-ph.EP2018

Limitation of atmospheric composition by combustion-explosion in exoplanetary atmospheres

John Lee Grenfell, Stefanie Gebauer, Mareike Godolt +3

This work presents theoretical studies which combine aspects of combustion and explosion theory with exoplanetary atmospheric science. Super Earths could possess a large amount of…