All Outputs (270)

Transit timing variations in the WASP-4 planetary system (2019)
Journal Article
Southworth, J., Dominik, M., Jørgensen, U. G., Andersen, M. I., Bozza, V., Burgdorf, M. J., …von Essen, C. (2019). Transit timing variations in the WASP-4 planetary system. Monthly Notices of the Royal Astronomical Society, 490(3), 4230 - 4236. https://doi.org/10.1093/mnras/stz2602

Transits in the planetary system WASP-4 were recently found to occur 80 s earlier than expected in observations from the TESS satellite. We present 22 new times of mid-transit that confirm the existence of transit timing variations, and are well fitt... Read More about Transit timing variations in the WASP-4 planetary system.

OGLE-2017-BLG-1186: first application of asteroseismology and Gaussian processes to microlensing (2019)
Journal Article
Li, S., Zang, W., Udalski, A., Shvartzvald, Y., Huber, D., Lee, C., …Hill, K. (2019). OGLE-2017-BLG-1186: first application of asteroseismology and Gaussian processes to microlensing. Monthly Notices of the Royal Astronomical Society, 488(3), 3308-3323. https://doi.org/10.1093/mnras/stz1873

We present the analysis of the event OGLE-2017-BLG-1186 from the 2017 Spitzer microlensing campaign. This is a remarkable microlensing event because its source is photometrically bright and variable, which makes it possible to perform an asteroseismi... Read More about OGLE-2017-BLG-1186: first application of asteroseismology and Gaussian processes to microlensing.

The EBLM Project VI. The mass and radius of five low-mass stars in F+M binaries discovered by the WASP survey (2019)
Journal Article
Gill, S., Maxted, P., Evans, J., Evans, D., Smalley, B., Gary, B., …West, R. (2019). The EBLM Project VI. The mass and radius of five low-mass stars in F+M binaries discovered by the WASP survey. Astronomy & Astrophysics, 626, Article A119. https://doi.org/10.1051/0004-6361/201833054

Some M-dwarfs around F-/G-type stars have been measured to be hotter and larger than predicted by stellar evolution models. Inconsistencies between observations and models need addressing with more mass, radius and luminosity measurements of low-mass... Read More about The EBLM Project VI. The mass and radius of five low-mass stars in F+M binaries discovered by the WASP survey.

An analysis of binary microlensing event OGLE-2015-BLG-0060 (2019)
Journal Article
Tsapras, Y., Cassan, A., Ranc, C., Bachelet, E., Street, R., Udalski, A., …collaboration, T. M. (2019). An analysis of binary microlensing event OGLE-2015-BLG-0060. Monthly Notices of the Royal Astronomical Society, 487(4), 4603 - 4614. https://doi.org/10.1093/mnras/stz1404

We present the analysis of stellar binary microlensing event OGLE-2015-BLG-0060 based on observations obtained from 13 different telescopes. Intensive coverage of the anomalous parts of the light curve was achieved by automated follow-up observations... Read More about An analysis of binary microlensing event OGLE-2015-BLG-0060.

SpUpNIC (Spectrograph Upgrade: Newly Improved Cassegrain): a versatile and efficient low- to medium-resolution, long-slit spectrograph on the South African Astronomical Observatory's 1.9-m telescope (2019)
Journal Article
Crause, L. A., Gilbank, D., van Gend, C., Worters, H. L., Sass, C., Kotze, E. J., …Burleigh, M. (2019). SpUpNIC (Spectrograph Upgrade: Newly Improved Cassegrain): a versatile and efficient low- to medium-resolution, long-slit spectrograph on the South African Astronomical Observatory's 1.9-m telescope. Journal of Astronomical Telescopes, Instruments, and Systems (JATIS), 5(2), Article 024007. https://doi.org/10.1117/1.jatis.5.2.024007

We report on the extensively upgraded Cassegrain spectrograph on the South African Astronomical Observatory (SAAO) 1.9-m telescope. The introduction of new collimator and camera optics, a new detector and controller, a rear-of-slit viewing camera to... Read More about SpUpNIC (Spectrograph Upgrade: Newly Improved Cassegrain): a versatile and efficient low- to medium-resolution, long-slit spectrograph on the South African Astronomical Observatory's 1.9-m telescope.

Qatar Exoplanet Survey: Qatar-8b, 9b, and 10b—A Hot Saturn and Two Hot Jupiters (2019)
Journal Article
Alsubai, K., Tsvetanov, Z. I., Pyrzas, S., Latham, D. W., Bieryla, A., Eastman, J., …Daassou, A. (2019). Qatar Exoplanet Survey: Qatar-8b, 9b, and 10b—A Hot Saturn and Two Hot Jupiters. Astronomical Journal, 157(6), 224 - 224. https://doi.org/10.3847/1538-3881/ab19bc

In this paper we present three new extrasolar planets from the Qatar Exoplanet Survey. Qatar-8b is a hot Saturn, with M P = 0.37 M J and R P = 1.3 R J, orbiting a solar-like star every P orb = 3.7 days. Qatar-9b is a hot Jupiter with a mass of M P =... Read More about Qatar Exoplanet Survey: Qatar-8b, 9b, and 10b—A Hot Saturn and Two Hot Jupiters.

OGLE-2018-BLG-0022: A Nearby M-dwarf Binary (2019)
Journal Article
Street, R., Bachelet, E., Tsapras, Y., Hundertmark, M., Bozza, V., Dominik, M., …Tregloan-Reed, J. (2019). OGLE-2018-BLG-0022: A Nearby M-dwarf Binary. Astronomical Journal, 157(6), Article 215. https://doi.org/10.3847/1538-3881/ab1538

We report observations of the binary microlensing event OGLE-2018-BLG-0022, provided by the Robotic Observations of Microlensing Events (ROME)/Reactive Event Assessment (REA) Survey, which indicate that the lens is a low-mass binary star consisting o... Read More about OGLE-2018-BLG-0022: A Nearby M-dwarf Binary.

Spectroscopic confirmation of the binary nature of the hybrid pulsator KIC 5709664 found with the frequency modulation method (2019)
Journal Article
Derekas, A., Murphy, S. J., Dálya, G., Szabó, R., Borkovits, T., Bókon, A., …Mészáros, S. (2019). Spectroscopic confirmation of the binary nature of the hybrid pulsator KIC 5709664 found with the frequency modulation method. Monthly Notices of the Royal Astronomical Society, 486(2), 2129-2136. https://doi.org/10.1093/mnras/stz875

We started a program to search for companions around hybrid δ Sct/γ Dor stars with the frequency modulation method using Kepler data. Our best candidate was KIC 5709664, where we could identify Fourier peaks with sidelobes, suggesting binary orbital... Read More about Spectroscopic confirmation of the binary nature of the hybrid pulsator KIC 5709664 found with the frequency modulation method.

Physical properties and transmission spectrum of the WASP-74 planetary system from multiband photometry (2019)
Journal Article
Mancini, L., Southworth, J., Mollière, P., Tregloan-Reed, J., Juvan, I. G., Chen, G., …Wertz, O. (2019). Physical properties and transmission spectrum of the WASP-74 planetary system from multiband photometry. Monthly Notices of the Royal Astronomical Society, 485(4), 5168-5179. https://doi.org/10.1093/mnras/stz661

We present broad-band photometry of 11 planetary transits of the hot Jupiter WASP-74 b, using three medium-class telescopes and employing the telescope-defocusing technique. Most of the transits were monitored through I filters and one was simultaneo... Read More about Physical properties and transmission spectrum of the WASP-74 planetary system from multiband photometry.

Spitzer Microlensing Parallax for OGLE-2017-BLG-0896 Reveals a Counter-rotating Low-mass Brown Dwarf (2019)
Journal Article
Shvartzvald, Y., Yee, J. C., Skowron, J., Lee, C., Udalski, A., Calchi Novati, S., …Southworth, J. (2019). Spitzer Microlensing Parallax for OGLE-2017-BLG-0896 Reveals a Counter-rotating Low-mass Brown Dwarf. Astronomical Journal, 157(3), Article 106. https://doi.org/10.3847/1538-3881/aafe12

The kinematics of isolated brown dwarfs in the Galaxy, beyond the solar neighborhood, is virtually unknown. Microlensing has the potential to probe this hidden population, as it can measure both the mass and five of the six phase-space coordinates (a... Read More about Spitzer Microlensing Parallax for OGLE-2017-BLG-0896 Reveals a Counter-rotating Low-mass Brown Dwarf.

OGLE-2014-BLG-1186: gravitational microlensing providing evidence for a planet orbiting the foreground star or for a close binary source? (2019)
Journal Article
Dominik, M., Bachelet, E., Bozza, V., Street, R. A., Han, C., Hundertmark, M., …Kozłowski, S. (2019). OGLE-2014-BLG-1186: gravitational microlensing providing evidence for a planet orbiting the foreground star or for a close binary source?. Monthly Notices of the Royal Astronomical Society, 484(4), 5608 - 5632. https://doi.org/10.1093/mnras/stz306

Discussing the particularly long gravitational microlensing event OGLE-2014-BLG-1186 with a time-scale tE ~ 300 d, we present a methodology for identifying the nature of localised deviations from single-lens point-source light curves, which ensures t... Read More about OGLE-2014-BLG-1186: gravitational microlensing providing evidence for a planet orbiting the foreground star or for a close binary source?.

The PDS 110 observing campaign – photometric and spectroscopic observations reveal eclipses are aperiodic (2019)
Journal Article
Osborn, H. P., Kenworthy, M., Rodriguez, J. E., de Mooij, E. J. W., Kennedy, G. M., Relles, H., …Zhou, G. (2019). The PDS 110 observing campaign – photometric and spectroscopic observations reveal eclipses are aperiodic. Monthly Notices of the Royal Astronomical Society, 485(2), 1614-1625. https://doi.org/10.1093/mnras/stz283

PDS 110 is a young disc-hosting star in the Orion OB1A association. Two dimming events of similar depth and duration were seen in 2008 (WASP) and 2011 (KELT), consistent with an object in a closed periodic orbit. In this paper, we present data from a... Read More about The PDS 110 observing campaign – photometric and spectroscopic observations reveal eclipses are aperiodic.

Deciphering the atmosphere of HAT-P-12b: solving discrepant results (2018)
Journal Article
Alexoudi, X., Mallonn, M., von Essen, C., Turner, J., Keles, E., Southworth, J., …Strassmeier, K. (2018). Deciphering the atmosphere of HAT-P-12b: solving discrepant results. Astronomy & Astrophysics, 620, Article A142. https://doi.org/10.1051/0004-6361/201833691

Context. Two independent investigations of the atmosphere of the hot Jupiter HAT-P-12b by two different groups resulted in discrepant solutions. Using broad-band photometry from the ground, one study found a flat and featureless transmission spectrum... Read More about Deciphering the atmosphere of HAT-P-12b: solving discrepant results.

WASP-147b, 160Bb, 164b, and 165b: two hot Saturns and two Jupiters, including two planets with metal-rich hosts (2018)
Journal Article
Lendl, M., Anderson, D. R., Bonfanti, A., Bouchy, F., Burdanov, A., Collier Cameron, A., …West, R. G. (2019). WASP-147b, 160Bb, 164b, and 165b: two hot Saturns and two Jupiters, including two planets with metal-rich hosts. Monthly Notices of the Royal Astronomical Society, 482(1), 301 -312. https://doi.org/10.1093/mnras/sty2667

We report the discovery of four transiting hot Jupiters, WASP-147, WASP-160B, WASP-164, and WASP-165 from the WASP survey. WASP-147b is a near Saturn-mass (MP = 0.28MJ) object with a radius of 1.11RJ orbiting a G4 star with a period of 4.6 d. WASP-16... Read More about WASP-147b, 160Bb, 164b, and 165b: two hot Saturns and two Jupiters, including two planets with metal-rich hosts.

Evidence for conservative mass transfer in the classical Algol system d Librae from its surface carbon-to-nitrogen abundance ratio (2018)
Journal Article
Dervişoğlu, A., Pavlovski, K., Lehmann, H., Southworth, J., & Bewsher, D. (2018). Evidence for conservative mass transfer in the classical Algol system d Librae from its surface carbon-to-nitrogen abundance ratio. Monthly Notices of the Royal Astronomical Society, 481(4), 5660 -5674. https://doi.org/10.1093/mnras/sty2684

Algol-type binary systems are the product of rapid mass transfer between the initially more massive component to its companion. It is still unknown whether the process is conservative, or whether substantial mass is lost from the system. The history... Read More about Evidence for conservative mass transfer in the classical Algol system d Librae from its surface carbon-to-nitrogen abundance ratio.

The Transiting Exoplanet Community Early Release Science Program for JWST (2018)
Journal Article
Bean, J. L., Stevenson, K. B., Batalha, N. M., Berta-Thompson, Z., Kreidberg, L., Crouzet, N., …Zingales, T. (2018). The Transiting Exoplanet Community Early Release Science Program for JWST. Publications of the Astronomical Society of the Pacific, 130(993), Article 114402. https://doi.org/10.1088/1538-3873/aadbf3

The James Webb Space Telescope (JWST) presents the opportunity to transform our understanding of planets and the origins of life by revealing the atmospheric compositions, structures, and dynamics of transiting exoplanets in unprecedented detail. How... Read More about The Transiting Exoplanet Community Early Release Science Program for JWST.

Physical properties and CNO abundances for high-mass stars in four main-sequence detached eclipsing binaries: V478 Cyg, AH Cep, V453 Cyg, and V578 Mon (2018)
Journal Article
Pavlovski, K., Southworth, J., & Tamajo, E. (2018). Physical properties and CNO abundances for high-mass stars in four main-sequence detached eclipsing binaries: V478 Cyg, AH Cep, V453 Cyg, and V578 Mon. Monthly Notices of the Royal Astronomical Society, 481(3), 3129 -3147. https://doi.org/10.1093/mnras/sty2516

We present ten high-precision light curves of four transits in the XO-1 planetary system, obtained using u, g, r, redshifted Ha, I and z filters. We use these to measure the physical properties, orbital ephemeris, and a transmission spectrum of the p... Read More about Physical properties and CNO abundances for high-mass stars in four main-sequence detached eclipsing binaries: V478 Cyg, AH Cep, V453 Cyg, and V578 Mon.

Physical properties and optical-infrared transmission spectrum of the giant planet XO-1 b (2018)
Journal Article
Southworth, J., Tregloan-Reed, J., Pinhas, A., Madhusudhan, N., Mancini, L., & Smith, A. M. S. (2018). Physical properties and optical-infrared transmission spectrum of the giant planet XO-1 b. Monthly Notices of the Royal Astronomical Society, 481(3), 3129-3147. https://doi.org/10.1093/mnras/sty2488

A prerequisite for probing theoretical evolutionary models for high-mass stars is the determination of stellar physical properties with a high accuracy. We do this for three binary systems containing components with masses above 10?M?: V478?Cyg, AH?C... Read More about Physical properties and optical-infrared transmission spectrum of the giant planet XO-1 b.

Infrared spectroscopy of the merger candidate KIC 9832227 (2018)
Journal Article
Pavlenko, Y., Evans, A., Banerjee, D., Southworth, J., Shahbandeh, M., & Davis, S. (2018). Infrared spectroscopy of the merger candidate KIC 9832227. Astronomy and Astrophysics, 615, Article A120. https://doi.org/10.1051/0004-6361/201832717

Context. It has been predicted that the object KIC 9832227 – a contact binary star – will undergo a merger in 2022.2±0.7.We describe the near infrared spectrum of this object as an impetus to obtain pre-merger data.
Aims. We aim to characterise (i)... Read More about Infrared spectroscopy of the merger candidate KIC 9832227.

WASP-104b is darker than charcoal (2018)
Journal Article
Močnik, T., Hellier, C., & Southworth, J. (2018). WASP-104b is darker than charcoal. Astronomical Journal, 156(2), Article 44. https://doi.org/10.3847/1538-3881/aacb26

By analyzing the K2 short-cadence data from Campaign 14, we detect phase-curve modulation in the light curve of the hot-Jupiter host star WASP-104. The ellipsoidal modulation is detected with high significance and in agreement with theoretical expect... Read More about WASP-104b is darker than charcoal.