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20022026
most citedLithium and Halpha in stars and brown dwarfs of sigma Orionis

191 citations · 1.2k across the 38 of their papers we have counts for

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21 papers · 1 filter

astro-ph.EP2026

WD 1054-226 revisited: a stable transiting debris system

J. Korth, A. J. Mustill, H. Parviainen +24

A growing number of white dwarfs (WDs) exhibit one or more signs of remnant planetary systems, including transits, infrared excesses, and atmospheric metal pollution. WD 1054-226 s…

astro-ph.EP2026★ 1 cited

Mass estimates of the young TOI-451 transiting planets: Multidimensional Gaussian Process on stellar spectroscopic and photometric signals

Oscar Barragán, Manuel Mallorquín, Jorge Fernández-Fernández +30

The young TOI-451 planetary system, aged 125 Myr, provides a unique opportunity to test theories of planetary internal structures and atmospheric mass loss through examination of i…

astro-ph.EP2025

ExoClock Project IV: A homogeneous catalogue of 620 updated exoplanet ephemerides

A. Kokori, A. Tsiaras, G. Pantelidou +323

The ExoClock project is an open platform aiming to monitor exoplanets by integrating observations from space and ground based telescopes. This study presents an updated catalogue o…

astro-ph.EP2024

TOI-2266 b: a keystone super-Earth at the edge of the M dwarf radius valley

Hannu Parviainen, Felipe Murgas, Emma Esparza-Borges +59

We validate the Transiting Exoplanet Survey Satellite (TESS) object of interest TOI-2266.01 (TIC 348911) as a small transiting planet (most likely a super-Earth) orbiting a faint M…

astro-ph.EP2022★ 14 cited

Search for planets around stars with wide brown dwarfs

J. Šubjak, N. Lodieu, P. Kabáth +6

Aims. The project aims to understand better the role of wide brown dwarf companions on planetary systems. Methods. We obtained high-resolution spectra of six bright stars with co-m…

astro-ph.EP2022★ 27 cited

A transiting, temperate mini-Neptune orbiting the M dwarf TOI-1759 unveiled by TESS

Néstor Espinoza, Enric Pallé, Jonas Kemmer +66

We report the discovery and characterization of TOI-1759~b, a temperate (400 K) sub-Neptune-sized exoplanet orbiting the M~dwarf TOI-1759 (TIC 408636441). TOI-1759 b was observed b…

astro-ph.EP2022★ 24 cited

Discovery and mass measurement of the hot, transiting, Earth-sized planet GJ 3929 b

J. Kemmer, S. Dreizler, D. Kossakowski +64

We report the discovery of GJ 3929 b, a hot Earth-sized planet orbiting the nearby M3.5 V dwarf star, GJ 3929 (G 180--18, TOI-2013). Joint modelling of photometric observations fro…

astro-ph.EP2021★ 14 cited

Is the orbit of the exoplanet WASP-43b really decaying? TESS and MuSCAT2 observations confirm no detection

Z. Garai, T. Pribulla, H. Parviainen +24

Up to now, WASP-12b is the only hot Jupiter confirmed to have a decaying orbit. The case of WASP-43b is still under debate. Recent studies preferred or ruled out the orbital decay…

astro-ph.EP2021★ 17 cited

TOI-2285b: A 1.7 Earth-radius Planet Near the Habitable Zone around a Nearby M Dwarf

Akihiko Fukui, Tadahiro Kimura, Teruyuki Hirano +60

We report the discovery of TOI-2285b, a sub-Neptune-sized planet transiting a nearby (42 pc) M dwarf with a period of 27.3 days. We identified the transit signal from the Transitin…

astro-ph.EP2021★ 74 cited

Diving Beneath the Sea of Stellar Activity: Chromatic Radial Velocities of the Young AU Mic Planetary System

Bryson Cale, Michael Reefe, Peter Plavchan +52

We present updated radial-velocity (RV) analyses of the AU Mic system. AU Mic is a young (22 Myr) early M dwarf known to host two transiting planets - days, $R_{b}=…

astro-ph.EP2021★ 20 cited

ESPRESSO Mass determination of TOI-263b: An extreme inhabitant of the brown dwarf desert

E. Palle, R. Luque, M. R. Zapatero Osorio +8

The TESS mission has reported a wealth of new planetary systems around bright and nearby stars amenable for detailed characterization of the planet properties and their atmospheres…

astro-ph.EP2020★ 28 cited

TOI-519 b: a short-period substellar object around an M dwarf validated using multicolour photometry and phase curve analysis

H. Parviainen, E. Palle, M. R. Zapatero-Osorio +43

Context: We report the discovery of TOI-519 b (TIC 218795833), a transiting substellar object (R = 1.07 RJup) orbiting a faint M dwarf (V = 17.35) on a 1.26 d orbit. Brown dwarfs a…

astro-ph.EP2020★ 21 cited

An enhanced slope in the transmission spectrum of the hot Jupiter WASP-104b

G. Chen, E. Palle, H. Parviainen +25

We present the optical transmission spectrum of the hot Jupiter WASP-104b based on one transit observed by the blue and red channels of the DBSP spectrograph at the Palomar 200-inc…

astro-ph.EP2020★ 43 cited

Discovery of a hot, transiting, Earth-sized planet and a second temperate, non-transiting planet around the M4 dwarf GJ 3473 (TOI-488)

J. Kemmer, S. Stock, D. Kossakowski +93

We present the confirmation and characterisation of GJ 3473 b (G 50--16, TOI-488.01), a hot Earth-sized planet orbiting an M4 dwarf star, whose transiting signal ($P=1.1980035\pm0.…

astro-ph.EP2020★ 18 cited

Obliquity measurement and atmospheric characterization of the WASP-74 planetary system

R. Luque, N. Casasayas-Barris, H. Parviainen +27

We present new transit observations of the hot Jupiter WASP-74 b ( 1860 K) using the high-resolution spectrograph HARPS-N and the multi-colour simultaneous imag…

astro-ph.EP2019★ 108 cited

He I 10830 Å in the transmission spectrum of HD 209458 b

F. J. Alonso-Floriano, I. A. G. Snellen, S. Czesla +27

Context: Recently, the He I triplet at 10830 Å has been rediscovered as an excellent probe of the extended and possibly evaporating atmospheres of close-in transiting planets. This…

astro-ph.EP2019★ 90 cited

Multicolour photometry for exoplanet candidate validation

Hannu Parviainen, Brandon Tingley, Hans. J. Deeg +17

Context. The TESS and PLATO missions are expected to find vast numbers of new transiting planet candidates. However, only a fraction of these candidates will be legitimate planets,…

astro-ph.EP2016★ 18 cited

Spectral energy distribution simulations of a possible ring structure around the young, red brown dwarf G196-3B

Olga V. Zakhozhay, María Rosa Zapatero Osorio, Víctor J. S. Béjar +1

The origin of the very red optical and infrared colours of intermediate-age (10 - 500 Myr) L-type dwarfs remains unknown. It has been suggested that low-gravity atmospheres c…

astro-ph.EP2016★ 46 cited

The K2-ESPRINT Project V: a short-period giant planet orbiting a subgiant star

Vincent Van Eylen, Simon Albrecht, Davide Gandolfi +31

We report on the discovery and characterization of the transiting planet K2-39b (EPIC 206247743b). With an orbital period of 4.6 days, it is the shortest-period planet orbiting a s…

astro-ph.EP2016★ 21 cited

The K2-ESPRINT Project II: Spectroscopic follow-up of three exoplanet systems from Campaign 1 of K2

Vincent Van Eylen, Grzegorz Nowak, Simon Albrecht +20

We report on Doppler observations of three transiting planet candidates that were detected during Campaign 1 of the K2 mission. The Doppler observations were conducted with FIES, H…

astro-ph.EP2015★ 22 cited

K2-31b, a grazing transiting hot Jupiter on an 1.26-day orbit around a bright G7V star

S. Grziwa, D. Gandolfi, Sz. Csizmadia +25

We report the discovery of K2-31b, the first confirmed transiting hot Jupiter detected by the K2 space mission. We combined K2 photometry with FastCam lucky imaging and FIES and HA…