TOI–757 b: an eccentric transiting mini–Neptune on a 17.5–d orbit (2024)
Journal Article
Alqasim, A., Grieves, N., Rosário, N. M., Gandolfi, D., Livingston, J. H., Sousa, S., Collins, K. A., Teske, J. K., Fridlund, M., Egger, J. A., Cabrera, J., Hellier, C., Lanza, A. F., Van Eylen, V., Bouchy, F., Oelkers, R. J., Srdoc, G., Shectman, S., Günther, M., Goffo, E., …Yee, S. W. (2024). TOI–757 b: an eccentric transiting mini–Neptune on a 17.5–d orbit. Monthly Notices of the Royal Astronomical Society, 533(1), 1-26. https://doi.org/10.1093/mnras/stae1767

We report the spectroscopic confirmation and fundamental properties of TOI$-$757 b, a mini$-$Neptune on a 17.5$-$d orbit transiting a bright star ($V\, =\, 9.7$ mag) discovered by the TESS mission. We acquired high$-$precision radial velocity measure... Read More about TOI–757 b: an eccentric transiting mini–Neptune on a 17.5–d orbit.

BEBOP V. Homogeneous stellar analysis of potential circumbinary planet hosts (2024)
Journal Article
Freckelton, A. V., Sebastian, D., Mortier, A., Triaud, A. H. M. J., Maxted, P. F. L., Acuña, L., Armstrong, D. J., Battley, M. P., Baycroft, T. A., Boisse, I., Bourrier, V., Carmona, A., Coleman, G. A. L., Cameron, A. C., Cortés-Zuleta, P., Delfosse, X., Dransfield, G., Duck, A., Forveille, T., French, J. R., …Willett, E. (2024). BEBOP V. Homogeneous stellar analysis of potential circumbinary planet hosts. Monthly Notices of the Royal Astronomical Society, 531(4), 4085-4098. https://doi.org/10.1093/mnras/stae1405

Planets orbiting binary systems are relatively unexplored compared to those around single stars. Detections of circumbinary planets and planetary systems offer a first detailed view into our understanding of circumbinary planet formation and dynamica... Read More about BEBOP V. Homogeneous stellar analysis of potential circumbinary planet hosts.

Planets observed with CHEOPS: Two super-Earths orbiting the red dwarf star TOI-776 (2024)
Journal Article
Fridlund, M., Georgieva, I. Y., Bonfanti, A., Alibert, Y., Persson, C. M., Gandolfi, D., Beck, M., Deline, A., Hoyer, S., Olofsson, G., Wilson, T. G., Barragán, O., Fossati, L., Mustill, A. J., Brandeker, A., Hatzes, A., Florén, H.-G., Simola, U., Hooton, M. J., Luque, R., …Walton, N. A. (2024). Planets observed with CHEOPS: Two super-Earths orbiting the red dwarf star TOI-776. Astronomy & Astrophysics, 684, Article A12. https://doi.org/10.1051/0004-6361/202243838

Context. M-dwarf stars are the most common of potential exoplanet host stars in the Galaxy. It is therefore very important to understand planetary systems orbiting such stars and to determine the physical parameters of such planets with high precisio... Read More about Planets observed with CHEOPS: Two super-Earths orbiting the red dwarf star TOI-776.

Limb darkening measurements from TESS and Kepler light curves of transiting exoplanets (2023)
Journal Article
Maxted. (2023). Limb darkening measurements from TESS and Kepler light curves of transiting exoplanets. Monthly Notices of the Royal Astronomical Society, 3723-3735. https://doi.org/10.1093/mnras/stac3741

Inaccurate limb-darkening models can be a significant source of error in the analysis of the light curves for transiting exoplanet and eclipsing binary star systems. To test the accuracy of published limb-darkening models, I have compared limb-darken... Read More about Limb darkening measurements from TESS and Kepler light curves of transiting exoplanets.

The HD 93963 A transiting system: A 1.04d super-Earth and a 3.65 d sub-Neptune discovered by TESS and CHEOPS (2022)
Journal Article
Maxted. (2022). The HD 93963 A transiting system: A 1.04d super-Earth and a 3.65 d sub-Neptune discovered by TESS and CHEOPS. Astronomy & Astrophysics, https://doi.org/10.1051/0004-6361/202243093

We present the discovery of two small planets transiting HD 93963A (TOI-1797), a GOV star (M* = 1.109 ± 0.043M?, R* = 1.043 ± 0.009 R?) in a visual binary system. We combined TESS and CHEOPS space-borne photometry with MuSCAT 2 ground-based photometr... Read More about The HD 93963 A transiting system: A 1.04d super-Earth and a 3.65 d sub-Neptune discovered by TESS and CHEOPS.

Fundamental effective temperature measurements for eclipsing binary stars – II. The detached F-type eclipsing binary CPD-54 810 (2022)
Journal Article
Miller, N. J., Maxted, P. F. L., Graczyk, D., Tan, T. G., & Southworth, J. (2022). Fundamental effective temperature measurements for eclipsing binary stars – II. The detached F-type eclipsing binary CPD-54 810. Monthly Notices of the Royal Astronomical Society, 517(4), 5129-5143. https://doi.org/10.1093/mnras/stac2968

CPD-54 810 is a double-lined detached eclipsing binary containing two mid-F type dwarfs on an eccentric 26-d orbit. We perform a combined analysis of the extensive photometry obtained by the TESS space mission along with previously published observat... Read More about Fundamental effective temperature measurements for eclipsing binary stars – II. The detached F-type eclipsing binary CPD-54 810.

The EBLM project – IX. Five fully convective M-dwarfs, precisely measured with CHEOPS and TESS light curves (2022)
Journal Article
Maxted. (2022). The EBLM project – IX. Five fully convective M-dwarfs, precisely measured with CHEOPS and TESS light curves. Monthly Notices of the Royal Astronomical Society, 519(3), 3546–3563. https://doi.org/10.1093/mnras/stac2565

Eclipsing binaries are important benchmark objects to test and calibrate stellar structure and evolution models. This is especially true for binaries with a fully convective M-dwarf component for which direct measurements of these stars' masses and r... Read More about The EBLM project – IX. Five fully convective M-dwarfs, precisely measured with CHEOPS and TESS light curves.

A stellar occultation by the transneptunian object (50000) Quaoar observed by CHEOPS (2022)
Journal Article
Maxted. (2022). A stellar occultation by the transneptunian object (50000) Quaoar observed by CHEOPS. Astronomy & Astrophysics, 1 - 9. https://doi.org/10.1051/0004-6361/202244221

Context. Stellar occultation is a powerful technique that allows the determination of some physical parameters of the occulting object. The result depends on the photometric accuracy, the temporal resolution, and the number of chords obtained. Space... Read More about A stellar occultation by the transneptunian object (50000) Quaoar observed by CHEOPS.

Fundamental effective temperature measurements for eclipsing binary stars – III. SPIRou near-infrared spectroscopy and CHEOPS photometry of the benchmark G0V star EBLM J0113+31 (2022)
Journal Article
Maxted, P. F. L., Miller, N. J., Hoyer, S., Adibekyan, V., Sousa, S. G., Billot, N., Fortier, A., Simon, A. E., Collier Cameron, A., Swayne, M. I., Gutermann, P., Triaud, A. H. M. J., Southworth, J., Alibert, Y., Alonso, R., Anglada, G., Bárczy, T., Barrado Navascues, D., Barros, S. C. C., Baumjohann, W., …Walton, N. (2022). Fundamental effective temperature measurements for eclipsing binary stars – III. SPIRou near-infrared spectroscopy and CHEOPS photometry of the benchmark G0V star EBLM J0113+31. Monthly Notices of the Royal Astronomical Society, 513(4), 6042-6057. https://doi.org/10.1093/mnras/stac1270

EBLM J0113+31 is a moderately bright (V = 10.1), metal-poor ([Fe/H] approximate to-0.3) GOV star with a much fainter M dwarf companion on a wide, eccentric orbit (= 14.3 d). We have used near-infrared spectroscopy obtained with the SPIRou spectrograp... Read More about Fundamental effective temperature measurements for eclipsing binary stars – III. SPIRou near-infrared spectroscopy and CHEOPS photometry of the benchmark G0V star EBLM J0113+31.

BEBOP III. Observations and an independent mass measurement of Kepler-16 (AB) b - the first circumbinary planet detected with radial velocities (2022)
Journal Article
Maxted, P. F. L., Triaud, A. H. M. J., Standing, M. R., Heidari, N., Martin, D. V., Boisse, I., Santerne, A., Correia, A. C. M., Acuña, L., Battley, M., Bonfils, X., Carmona, A., Collier Cameron, A., Cortés-Zuleta, P., Dransfield, G., Dalal, S., Deleuil, M., Delfosse, X., Faria, J., Forveille, T., …Willett, E. (2022). BEBOP III. Observations and an independent mass measurement of Kepler-16 (AB) b - the first circumbinary planet detected with radial velocities. Monthly Notices of the Royal Astronomical Society, 511(3), 3561-3570. https://doi.org/10.1093/mnras/stab3712

The radial velocity method is amongst the most robust and most established means of detecting exoplanets. Yet, it has so far failed to detect circumbinary planets despite their relatively high occurrence rates. Here, we report velocimetric measuremen... Read More about BEBOP III. Observations and an independent mass measurement of Kepler-16 (AB) b - the first circumbinary planet detected with radial velocities.

Spi-OPS: Spitzer and CHEOPS confirm the near-polar orbit of MASCARA-1 b and reveal a hint of dayside reflection (2022)
Journal Article
Maxted. (2022). Spi-OPS: Spitzer and CHEOPS confirm the near-polar orbit of MASCARA-1 b and reveal a hint of dayside reflection. Astronomy & Astrophysics, https://doi.org/10.1051/0004-6361/202141645

<jats:p><jats:italic>Context.</jats:italic> The light curves of tidally locked hot Jupiters transiting fast-rotating, early-type stars are a rich source of information about both the planet and star, with full-phase coverage enabling a detailed atmos... Read More about Spi-OPS: Spitzer and CHEOPS confirm the near-polar orbit of MASCARA-1 b and reveal a hint of dayside reflection.

BEBOP II: sensitivity to sub-Saturn circumbinary planets using radial-velocities (2022)
Journal Article
Maxted, & Hellier. (2022). BEBOP II: sensitivity to sub-Saturn circumbinary planets using radial-velocities. Monthly Notices of the Royal Astronomical Society, 3571 - 3583. https://doi.org/10.1093/mnras/stac113

BEBOP is a radial-velocity survey that monitors a sample of single-lined eclipsing binaries, in search of circumbinary planets by using high-resolution spectrographs. Here, we describe and test the methods we use to identify planetary signals within... Read More about BEBOP II: sensitivity to sub-Saturn circumbinary planets using radial-velocities.

Detection of the tidal deformation of WASP-103b at 3 s with CHEOPS (2022)
Journal Article
Maxted. (2022). Detection of the tidal deformation of WASP-103b at 3 s with CHEOPS. Astronomy & Astrophysics, https://doi.org/10.1051/0004-6361/202142196

Context. Ultra-short period planets undergo strong tidal interactions with their host star which lead to planet deformation and orbital tidal decay.

Aims. WASP-103b is the exoplanet with the highest expected deformation signature in its transit li... Read More about Detection of the tidal deformation of WASP-103b at 3 s with CHEOPS.

TIC 172900988: A Transiting Circumbinary Planet Detected in One Sector of TESS Data (2021)
Journal Article
Hellier, & Maxted. (2021). TIC 172900988: A Transiting Circumbinary Planet Detected in One Sector of TESS Data. Astronomical Journal, https://doi.org/10.3847/1538-3881/ac223a

We report the first discovery of a transiting circumbinary planet detected from a single sector of Transiting Exoplanet Survey Satellite (TESS) data. During Sector 21, the planet TIC 172900988b transited the primary star and then five days later it t... Read More about TIC 172900988: A Transiting Circumbinary Planet Detected in One Sector of TESS Data.

The changing face of AU Mic b: stellar spots, spin-orbit commensurability, and transit timing variations as seen by CHEOPS and TESS (2021)
Journal Article
Maxted. (2021). The changing face of AU Mic b: stellar spots, spin-orbit commensurability, and transit timing variations as seen by CHEOPS and TESS. Astronomy & Astrophysics, 654, Article A159

AU Mic is a young planetary system with a resolved debris disc showing signs of planet formation and two transiting warm Neptunes near mean-motion resonances. Here we analyse three transits of AU Mic b observed with the CHaracterising ExOPlanet Satel... Read More about The changing face of AU Mic b: stellar spots, spin-orbit commensurability, and transit timing variations as seen by CHEOPS and TESS.

The EBLM project - VIII. First results for M-dwarf mass, radius, and effective temperature measurements using CHEOPS light curves (2021)
Journal Article
Hellier, & Maxted. (2021). The EBLM project - VIII. First results for M-dwarf mass, radius, and effective temperature measurements using CHEOPS light curves. Monthly Notices of the Royal Astronomical Society, 306 - 322. https://doi.org/10.1093/mnras/stab1687

The accuracy of theoretical mass, radius, and effective temperature values for M-dwarf stars is an active topic of debate. Differences between observed and theoretical values have raised the possibility that current theoretical stellar structure and... Read More about The EBLM project - VIII. First results for M-dwarf mass, radius, and effective temperature measurements using CHEOPS light curves.

Exploiting timing capabilities of the CHEOPS mission with warm-Jupiter planets (2021)
Journal Article
Maxted. (2021). Exploiting timing capabilities of the CHEOPS mission with warm-Jupiter planets. Monthly Notices of the Royal Astronomical Society, 3810 - 3830. https://doi.org/10.1093/mnras/stab1782

We present 17 transit light curves of seven known warm-Jupiters observed with the CHaracterising ExOPlanet Satellite (CHEOPS). The light curves have been collected as part of the CHEOPS Guaranteed Time Observation (GTO) program that searches for tran... Read More about Exploiting timing capabilities of the CHEOPS mission with warm-Jupiter planets.

A search for transiting planets around hot subdwarfs (2021)
Journal Article
Maxted. (2021). A search for transiting planets around hot subdwarfs. Astronomy & Astrophysics, https://doi.org/10.1051/0004-6361/202140381

Context. Hot subdwarfs experienced strong mass loss on the red giant branch (RGB) and are now hot and small He-burning objects. These stars constitute excellent opportunities for addressing the question of the evolution of exoplanetary systems direct... Read More about A search for transiting planets around hot subdwarfs.

The surface brightness–colour relations based on eclipsing binary stars and calibrated with Gaia EDR3 (2021)
Journal Article
Graczyk, D., Pietrzyński, G., Gałan, C., Gieren, W., Tkachenko, A., Anderson, R., Gallenne, A., Górski, M., Hajdu, G., Kałuszyński, M., Karczmarek, P., Kervella, P., Maxted, P., Nardetto, N., Narloch, W., Pavlovski, K., Pilecki, B., Pych, W., Southworth, J., Storm, J., …Konorski, P. (2021). The surface brightness–colour relations based on eclipsing binary stars and calibrated with Gaia EDR3. Astronomy & Astrophysics, 649, Article A109. https://doi.org/10.1051/0004-6361/202140571

Aims. The surface brightness–colour relation (SBCR) is a basic tool for establishing precise and accurate distances within the Local Group. Detached eclipsing binary stars with accurately determined radii and trigonometric parallaxes allow calibratio... Read More about The surface brightness–colour relations based on eclipsing binary stars and calibrated with Gaia EDR3.

BG Ind: the nearest doubly eclipsing, compact hierarchical quadruple system (2021)
Journal Article
Borkovits, T., Rappaport, S. A., Maxted, P. F. L., Terentev, I., Omohundro, M., Gagliano, R., Jacobs, T., Kristiansen, M. H., LaCourse, D., Schwengeler, H. M., Vanderburg, A., & Blackford, M. G. (2021). BG Ind: the nearest doubly eclipsing, compact hierarchical quadruple system. Monthly Notices of the Royal Astronomical Society, 503(3), 3759-3774. https://doi.org/10.1093/mnras/stab621

BG Ind is a well-studied, bright, nearby binary consisting of a pair of F stars in a 1.46-d orbit. We have discovered in the TESS light curve for TIC 229804573 (aka BG Ind), a second eclipsing binary in the system with a 0.53-d period. Our subsequent... Read More about BG Ind: the nearest doubly eclipsing, compact hierarchical quadruple system.