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    Erratum: Large-scale changes of the cloud coverage in the ϵ Indi Ba and Bb system (Monthly Notices of the Royal Astronomical Society DOI: 10.1093/jeea/staa1344)

    , Article Monthly Notices of the Royal Astronomical Society ; Volume 506, Issue 3 , 2021 , Pages 3418- ; 00358711 (ISSN) Hitchcock, J.A ; Helling, C ; Scholz, A ; Hodosan, G ; Dominik, M ; Hundertmark, M ; Jørgensen, U. G ; Longa Peña, P ; Sajadian, S ; Skottfelt, J ; Snodgrass, C ; Bozza, V ; Burgdorf, M. J ; Campbell White, J ; Figuera Jaimes, R ; Fujii, Y. I ; Haikala, L. K ; Henning, T ; Hinse, T. C ; Lowry, S ; Mancini, L ; Rahvar, S ; Rabus, M ; Southworth, J ; Von Essen, C ; Sharif University of Technology
    Oxford University Press  2021
    Abstract
    The Acknowledgements section of Hitchcock et al. (2020) should have included the following grant information: ‘TCH acknowledges financial support from the National Research Foundation (NRF; No. 2019R1I1A1A01059609)’. This change does not affect any of the scientific content of the paper. © 2021 Oxford University Press. All rights reserved  

    Realisation of a fully-deterministic microlensing observing strategy for inferring planet populations

    , Article Astronomische Nachrichten ; Volume 331, Issue 7 , July , 2010 , Pages 671-691 ; 00046337 (ISSN) Dominik, M ; Jørgensen, U. G ; Rattenbury, N. J ; Mathiasen, M ; Hinse, T.C ; Novati, S. C ; Harpsøe, K ; Bozza, V ; Anguita, T ; Burgdorf, M. J ; Horne, K ; Hundertmark, M ; Kerins, E ; Kjærgaard, P ; Liebig, C ; Mancini, L ; Masi, G ; Rahvar, S ; Ricci, D ; Scarpetta, G ; Snodgrass, C ; Southworth, J ; Street, R. A ; Surdej, J ; Thöne, C. C ; Tsapras, Y ; Wambsganss, J ; Zub, M ; Sharif University of Technology
    2010
    Abstract
    Within less than 15 years, the count of known planets orbiting stars other than the Sun has risen from none to more than 400 with detections arising from four successfully applied techniques: Doppler-wobbles, planetary transits, gravitational microlensing, and direct imaging. While the hunt for twin Earths is on, a statistically well-defined sample of the population of planets in all their variety is required for probing models of planet formation and orbital evolution so that the origin of planets that harbour life, like and including ours, can be understood. Given the different characteristics of the detection techniques, a complete picture can only arise from a combination of their... 

    Large-scale changes of the cloud coverage in the ϵ Indi Ba and Bb system

    , Article Monthly Notices of the Royal Astronomical Society ; Volume 495, Issue 4 , May , 2021 , Pages 3881-3899 ; 00358711 (ISSN) Hitchcock, J. A ; Helling, Ch ; Scholz, A ; Hodosan, G ; Dominik, M ; Hundertmark, M ; Jørgensen, U. G ; Longa Peña, P ; Sajadian, S ; Skottfelt, J ; Snodgrass, C ; Bozza, V ; Burgdorf, M. J ; Campbell White, J ; Jaimes, R. F ; Fujii, Y. I ; Haikala, L. K ; Henning, T ; Hinse, T. C ; Lowry, S ; Mancini, L ; Rahvar, S ; Rabus, M ; Southworth, J ; Von Essen, C ; The MiNDSTEp Collaboration ; Sharif University of Technology
    Oxford University Press  2021
    Abstract
    We present the results of 14 nights of I-band photometric monitoring of the nearby brown dwarf binary, ϵ Indi Ba and Bb. Observations were acquired over 2 months, with a total of close to 42 h of coverage at a typically high cadence of 1.4 min. At a separation of just 0.7 arcsec, we do not resolve the individual components, and so effectively treat the binary as if it were a single object. However, ϵ Indi Ba (spectral type T1) is the brightest known T-type brown dwarf, and is expected to dominate the photometric signal. We typically find no strong variability associated with the target during each individual night of observing, but see significant changes in mean brightness – by as much as... 

    OGLE-2017-BLG-0329L: a microlensing binary characterized with dramatically enhanced precision using data from space-based observations

    , Article Astrophysical Journal ; Volume 859, Issue 2 , 1 June , 2018 ; 0004637X (ISSN) Han, C ; Novati, S. C ; Udalski, A ; Lee, C. U ; Gould, A ; Bozza, V ; Mroz, P ; Pietrukowicz, P ; Skowron, J ; Szymanski, M. K ; Poleski, R ; Soszynski, I ; Kozłowski, S ; Ulaczyk, K ; Pawlak, M ; Rybicki, K ; Iwanek, P ; Albrow, M. D ; Chung, S. J ; Hwang, K. H ; Jung, Y. K ; Ryu, Y. H ; Shin, I. G ; Shvartzvald, Y ; Yee, J. C ; Zang, W ; Zhu, W ; Cha, S. M ; Kim, D. J ; Kim, H. W ; Kim, S. L ; Lee, D. J ; Lee, Y ; Park, B. G ; Pogge, R. W ; Kim, W. T ; Beichman, C ; Bryden, G ; Carey, S ; Gaudi, B. S ; Henderson, C. B ; Dominik, M ; Helling, C ; Hundertmark, M ; Jorgensen, U. G ; Longa Pena, P ; Lowry, S ; Sajadian, S ; Burgdorf, M. J ; Campbell White, J ; Ciceri, S ; Evans, D. F ; Haikala, L. K ; Hinse, T. C ; Rahvar, S ; Rabus, M ; Snodgrass, C ; Sharif University of Technology
    Institute of Physics Publishing  2018
    Abstract
    Mass measurements of gravitational microlenses require one to determine the microlens parallax π E, but precise π E measurement, in many cases, is hampered due to the subtlety of the microlens-parallax signal combined with the difficulty of distinguishing the signal from those induced by other higher-order effects. In this work, we present the analysis of the binary-lens event OGLE-2017-BLG-0329, for which π E is measured with a dramatically improved precision using additional data from space-based Spitzer observations. We find that while the parallax model based on the ground-based data cannot be distinguished from a zero-π E model at the 2σ level, the addition of the Spitzer data enables... 

    High-precision photometry by telescope defocusing - IV. Confirmation of the huge radius of WASP-17b

    , Article Monthly Notices of the Royal Astronomical Society ; Volume 426, Issue 2 , October , 2012 , Pages 1338-1348 ; 00358711 (ISSN) Southworth, J ; Hinse, T. C ; Dominik, M ; Fang, X. S ; Harpsøe, K ; Jørgensen, U. G ; Kerins, E ; Liebig, C ; Mancini, L ; Skottfelt, J ; Anderson, D. R ; Smalley, B ; Tregloan Reed, J ; Wertz, O ; Alsubai, K. A ; Bozza, V ; Calchi Novati, S ; Dreizler, S ; Gu, S. H ; Hundertmark, M ; Jessen Hansen, J ; Kains, N ; Kjeldsen, H ; Lund, M. N ; Lundkvist, M ; Mathiasen, M ; Penny, M. T ; Rahvar, S ; Ricci, D ; Scarpetta, G ; Snodgrass, C ; Surdej, J ; Sharif University of Technology
    2012
    Abstract
    We present photometric observations of four transits in the WASP-17 planetary system, obtained using telescope defocusing techniques and with scatters reaching 0.5mmag per point. Our revised orbital period is 4.0 ± 0.6s longer than previous measurements, a difference of 6.6σ, and does not support the published detections of orbital eccentricity in this system. We model the light curves using the jktebop code and calculate the physical properties of the system by recourse to five sets of theoretical stellar model predictions. The resulting planetary radius, R b = 1.932 ± 0.052 ± 0.010R Jup (statistical and systematic errors, respectively), provides confirmation that WASP-17b is the largest... 

    Self‐assembled, nanowire network electrodes for depleted bulk heterojunction solar cells (Adv. Mater. 12/2013) [electronic resource]

    , Article Journal of Advanced Materials ; March 2013, Vol. 25, Issue 12, PP. 1768 Lan, X. (Xinzheng) ; Bai, Jing ; Masala, Silvia ; Thon, Susanna M ; Ren, Yuan ; Kramer, Illan J ; Hoogland, Sjoerd ; Simchi, A. (Abdolreza) ; Koleilat, Ghada I ; Paz‐Soldan, Daniel ; Ning, Zhijun ; Labelle, André J ; Kim, Jin Young ; Jabbour, Ghassan ; Sargent, Edward H ; Sharif University of Technology
    Abstract
    A solution-processed, bottom-up nanowire network electrode is developed and employed in a bulk heterojunction colloidal quantum dot solar cell. The electrode features a ZnO template which is converted into locally connected, infi ltratable TiO2 nanowires. The new electrode allows the application of a thicker light absorbing fi lm without compromising the charge extraction, as reported by Edward H. Sargent, Ghassan Jabbour, and co-workers on page 1769. The frontispiece shows schematically the electrode shape and the resultant device architecture  

    Physical properties and transmission spectrum of theWASP-74 planetary system from multiband photometry

    , Article Monthly Notices of the Royal Astronomical Society ; Volume 485, Issue 4 , 2019 , Pages 5168-5179 ; 00358711 (ISSN) Mancini, L ; Southworth, J ; Mollière, P ; Tregloan Reed, J ; Juvan, I. G ; Chen, G ; Sarkis, P ; Bruni, I ; Ciceri, S ; Andersen, M. I ; Bozza, V ; Bramich, D. M ; Burgdorf, M ; D'Ago, G ; Dominik, M ; Evans, D. F ; Figuera Jaimes, R ; Fossati, L ; Henning, T ; Hinse, T. C ; Hundertmark, M ; Jørgensen, U. G ; Kerins, E ; Korhonen, H ; Küffmeier, M ; Longa, P ; Peixinho, N ; Popovas, A ; Rabus, M ; Rahvar, S ; Skottfelt, J ; Snodgrass, C ; Tronsgaard, R ; Wang, Y ; Wertz, O ; Sharif University of Technology
    Oxford University Press  2019
    Abstract
    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 simultaneously observed in five optical (U, g', r', i', z') and three near-infrared (J, H, K) passbands, for a total of 18 light curves. We also obtained new high-resolution spectra of the host star. We used these new data to review the orbital and physical properties of the WASP-74 planetary system. We were able to better constrain the main system characteristics, measuring smaller radius and mass for both the hot Jupiter and its host star than previously... 

    High-resolution imaging of transiting extrasolar planetary systems (HITEP) II. Lucky imaging results from 2015 and 2016

    , Article Astronomy and Astrophysics ; Volume 610 , 2018 ; 00046361 (ISSN) Evans, D. F ; Southworth, J ; Smalley, B ; Jørgensen, U. G ; Dominik, M ; Andersen, M. I ; Bozza, V ; Bramich, D. M ; Burgdorf, M. J ; Ciceri, S ; D'Ago, G ; Jaimes, R. F ; Gu, S. H ; Hinse, T. C ; Henning, Th ; Hundertmark, M ; Kains, N ; Kerins, E ; Korhonen, H ; Kokotanekova, R ; Kuffmeier, M ; Longa Peña, P ; Mancini, L ; MacKenzie, J ; Popovas, A ; Rabus, M ; Rahvar, S ; Sajadian, S ; Snodgrass, C ; Skottfelt, J ; Surdej, J ; Tronsgaard, R ; Unda-Sanzana, E ; Von Essen, C ; Wang, Y. B ; Wertz, O ; Sharif University of Technology
    EDP Sciences  2018
    Abstract
    Context. The formation and dynamical history of hot Jupiters is currently debated, with wide stellar binaries having been suggested as a potential formation pathway. Additionally, contaminating light from both binary companions and unassociated stars can significantly bias the results of planet characterisation studies, but can be corrected for if the properties of the contaminating star are known. Aims. We search for binary companions to known transiting exoplanet host stars, in order to determine the multiplicity properties of hot Jupiter host stars. We also search for and characterise unassociated stars along the line of sight, allowing photometric and spectroscopic observations of the... 

    The transiting system GJ1214: High-precision defocused transit observations and a search for evidence of transit timing variation

    , Article Astronomy and Astrophysics ; Volume 549 , 2012 ; 00046361 (ISSN) Harpsøe, K. B. W ; Hardis, S ; Hinse, T. C ; Jørgensen, U. G ; Mancini, L ; Southworth, J ; Alsubai, K. A ; Bozza, V ; Browne, P ; Burgdorf, M. J ; Calchi Novati, S ; Dodds, P ; Dominik, M ; Fang, X. S ; Finet, F ; Gerner, T ; Gu, S. H ; Hundertmark, M ; Jessen Hansen, J ; Kains, N ; Kerins, E ; Kjeldsen, H ; Liebig, C ; Lund, M. N ; Lundkvist, M ; Mathiasen, M ; Nesvorný, D ; Nikolov, N ; Penny, M. T ; Proft, S ; Rahvar, S ; Ricci, D ; Sahu, K. C ; Scarpetta, G ; Schäfer, S ; Schönebeck, F ; Snodgrass, C ; Skottfelt, J ; Surdej, J ; Tregloan Reed, J ; Wertz, O ; Sharif University of Technology
    2012
    Abstract
    Aims. We present 11 high-precision photometric transitobservations of the transiting super-Earth planet GJ≠1214≠b. Combining these data with observations from other authors, we investigate the ephemeris for possible signs of transit timing variations (TTVs) using a Bayesian approach. Methods. The observations were obtained using telescope-defocusing techniques, and achieve a high precision with random errors in the photometry as low as 1 mmag per point. To investigate the possibility of TTVs in the light curve, we calculate the overall probability of a TTV signal using Bayesian methods. Results. The observations are used to determine the photometric parameters and the physical properties... 

    High-precision photometry by telescope defocusing - V.WASP-15 and WASP-16

    , Article Monthly Notices of the Royal Astronomical Society ; Volume 434, Issue 2 , July , 2013 , Pages 1300-1308 ; 00358711 (ISSN) Southworth, J ; Mancini, L ; Browne, P ; Burgdorf, M ; Calchi Novati, S ; Dominik, M ; Gerner, T ; Hinse, T. C ; Jørgensen, U. G ; Kains, N ; Ricci, D ; Scháfer, S ; Schónebeck, F ; Tregloan-Reed, J ; Alsubai, K. A ; Bozza, V ; Chen, G ; Dodds, P ; Dreizler, S ; Fang, X. S ; Finet, F ; Gu, S. H ; Hardis, S ; Harpsøe, K ; Henning, T ; Hundertmark, M ; Jessen-Hansen, J ; Kerins, E ; Kjeldsen, H ; Liebig, C ; Lund, M. N ; Lundkvist, M ; Mathiasen, M ; Nikolov, N ; Penny, M. T ; Proft, S ; Rahvar, S ; Sahu, K ; Scarpetta, G ; Skottfelt, J ; Snodgrass, C ; Surdej, J ; Wertz, O ; Sharif University of Technology
    2013
    Abstract
    We present newphotometric observations ofWASP-15 andWASP-16, two transiting extrasolar planetary systems with measured orbital obliquities but without photometric follow-up since their discovery papers. Our new data for WASP-15 comprise observations of one transit simultaneously in four optical passbands using GROND on the MPG/European Southern Observatory (ESO) 2.2 m telescope, plus coverage of half a transit from DFOSC on the Danish 1.54 m telescope, both at ESO La Silla. ForWASP-16 we present observations of fourcomplete transits, all from the Danish telescope. We use these new data to refine the measured physical properties and orbital ephemerides of the two systems. Whilst our results... 

    Physical properties, transmission and emission spectra of the WASP-19 planetary system from multi-colour photometry

    , Article Monthly Notices of the Royal Astronomical Society ; Volume 436, Issue 1 , 2013 , Pages 2-18 ; 00358711 (ISSN) Mancini, L ; Ciceri, S ; Chen, G ; Tregloan Reed, J ; Fortney, J. J ; Southworth, J ; Tan, T.G ; Burgdorf, M ; Calchi Novati, S ; Dominik, M ; Fang, X. S ; Finet, F ; Gerner, T ; Hardis, S ; Hinse, T. C ; Jørgensen, U. G ; Liebig, C ; Nikolov, N ; Ricci, D ; Schäfer, S ; Schönebeck, F ; Skottfelt, J ; Wertz, O ; Alsubai, K. A ; Bozza, V ; Browne, P ; Dodds, P ; Gu, S. H ; Harpsøe, K ; Henning, T ; Hundertmark, M ; Jessen Hansen, J ; Kains, N ; Kerins, E ; Kjeldsen, H ; Lund, M. N ; Lundkvist, M ; Madhusudhan, N ; Mathiasen, M ; Penny, M. T ; Prof, S ; Rahvar, S ; Sahu, K ; Scarpetta, G ; Snodgrass, C ; Surdej, J ; Sharif University of Technology
    2013
    Abstract
    We present new ground-based, multi-colour, broad-band photometric measurements of the physical parameters, transmission and emission spectra of the transiting extrasolar planet WASP-19b. The measurements are based on observations of eight transits and four occultations through a Gunn i filter using the 1.54-m Danish Telescope, 14 transits through an Rc filter at the Perth Exoplanet SurveyTelescope (PEST) observatory and one transit observed simultaneously through four optical (Sloan g', r', i', z') and three near-infrared (J,H,K) filters, using the Gamma Ray Burst Optical and Near-Infrared Detector (GROND) instrument on the MPG/ESO 2.2-m telescope. The GROND optical light curves have a... 

    OGLE-2017-BLG-1434Lb: eighth q<1×10-4 mass-ratio microlens planet confirms turnover in planet mass-ratio function

    , Article Acta Astronomica ; Volume 68, Issue 1 , 2018 , Pages 1-42 ; 00015237 (ISSN) Udalski, A ; Ryu, Y. H ; Sajadian, S ; Gould, A ; Mroz, P ; Poleski, R ; Szymanski, M. K ; Skowron, J ; Soszynski, I ; Kozlowski, S ; Pietrukowicz, P ; Ulaczyk, K ; Pawlak, M ; Rybicki, K ; Iwanek, P ; Albrow, M. D ; Chung, S. J ; Han, C ; Hwang, K. H ; Jung, Y. K ; Shin, I. G ; Shvartzvald, Y ; Yee, J. C ; Zang, W ; Zhu, W ; Cha, S. M ; Kim, D. J ; Kim, H. W ; Kim, S. L ; Lee, C. U ; Lee, D. J ; Lee, Y ; Park, B. G ; Pogge, R. W ; Bozza, V ; Dominik, M ; Helling, C ; Hundertmark, M ; Jorgensen, U. G ; Longa Pena, P ; Lowry, S ; Burgdorf, M ; CampbellWhite, J ; Ciceri, S ; Evans, D ; Figuera Jaimes, R ; Fujii, Y. I ; Haikala, L. K ; Henning, T ; Hinse, T. C ; Mancini, L ; Peixinho, N ; Rahvar, S ; Rabus, M ; Skottfelt, J ; Snodgrass, C ; Southworth, J ; Von Essen, C ; Sharif University of Technology
    2018
    Abstract
    We report the discovery of a cold Super-Earth planet (mp = 4.4 ± 0.5 M) orbiting a lowmass (M = 0.23 ± 0.03 M) M dwarf at projected separation a = 1.18 ± 0.10 a.u., i.e., about 1.9 times the distance the snow line. The system is quite nearby for a microlensing planet, DL = 0.86 ± 0.09 kpc. Indeed, it was the large lens-source relative parallax πrel = 1.0 mas (combined with the low mass M) that gave rise to the large, and thus well-measured, "microlens parallax πE ∞ (πrel/M)1/2 that enabled these precise measurements. OGLE-2017-BLG-1434Lb is the eighth microlensing planet with planet-host mass ratio q < 1×10-4. We apply a new planet-detection sensitivity method, which is a variant of "V/Vmax,...