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Comparative Study of Neural Network Frameworks for the Next Generation of Adaptive Optics Systems (2017)
Journal Article
González-Gutiérrez, C., Santos, J., Martínez-Zarzuela, M., Basden, A., Osborn, J., Díaz-Pernas, F., & De Cos Juez, F. (2017). Comparative Study of Neural Network Frameworks for the Next Generation of Adaptive Optics Systems. Sensors, 17(6), Article 1263. https://doi.org/10.3390/s17061263

Many of the next generation of adaptive optics systems on large and extremely large telescopes require tomographic techniques in order to correct for atmospheric turbulence over a large field of view. Multi-object adaptive optics is one such techniqu... Read More about Comparative Study of Neural Network Frameworks for the Next Generation of Adaptive Optics Systems.

On-sky demonstration of matched filters for wavefront measurements using ELT-scale elongated laser guide stars (2017)
Journal Article
Basden, A., Bardou, L., Bonaccini-Calia, D., Buey, T., Centrone, M., Chemla, F., …Vidal, F. (2017). On-sky demonstration of matched filters for wavefront measurements using ELT-scale elongated laser guide stars. Monthly Notices of the Royal Astronomical Society, 466(4), 5003-5010. https://doi.org/10.1093/mnras/stx062

The performance of adaptive optics systems is partially dependent on the algorithms used within the real-time control system to compute wavefront slope measurements. We demonstrate the use of a matched filter algorithm for the processing of elongated... Read More about On-sky demonstration of matched filters for wavefront measurements using ELT-scale elongated laser guide stars.

Preliminary on-sky results of the CANARY experiment with an ELT-elongated sodium LGS (2017)
Presentation / Conference Contribution
Bardou, L., Gendron, E., Rousset, G., Gratadour, D., Basden, A. G., Bonaccini, D., Buey, T., Centrone, M., Chemla, F., Lombardi, G., Marchetti, E., Morris, T. J., Myers, R. M., Osborn, J., Townson, M. J., Vidal, F., & Reyes Garcia-Talavera, M. (2017, June). Preliminary on-sky results of the CANARY experiment with an ELT-elongated sodium LGS. Presented at Adaptive Optics for Extremely Large Telescopes 5, Tenerife, Canary Islands, Spain

We present on-sky results of wavefront sensing on an elongated LGS. These results are derived from observations made with the multi-object AO demonstrator CANARY on the William Herschel Telescope (WHT) in La Palma. The laser guide star is produced us... Read More about Preliminary on-sky results of the CANARY experiment with an ELT-elongated sodium LGS.

Photometry and Spectrum measurements of the Laser Guide Star beam emission at Observatorio del Roque de Los Muchachos with the Gran Telescope Canarias (2017)
Presentation / Conference Contribution
Lombardi, G., Calia, B., Centrone, M., Talavera, M. R. G., Morris, T., Pfrommer, T., Basden, A., Vidal, F., Gendron, E., Rousset, G., Mayers, R., Osborn, J., Reeves, A., Talbot, R., Townson, M., Lavers, A. C., & Postigoh, A. D. U. (2017, June). Photometry and Spectrum measurements of the Laser Guide Star beam emission at Observatorio del Roque de Los Muchachos with the Gran Telescope Canarias. Presented at Adaptive Optics for Extremely Large Telescopes 5, Tenerife, Canary Islands, Spain

In the past years ESO has built together with industry a transportable Laser Guide Star Unit (WLGSU) to test the laser technology while supporting some strategic experiments for the LGS-AO technologies. Since July 2016, the WLGSU has been installed a... Read More about Photometry and Spectrum measurements of the Laser Guide Star beam emission at Observatorio del Roque de Los Muchachos with the Gran Telescope Canarias.

Stereo-SCIDAR: Instrument and First Commissioning Results (2016)
Journal Article
Derie, F., Wilson, R., Osborn, J., Dubbeldam, M., Sarazin, M., Ridding, R., Navarrete, J., & Lelouarn, M. (2016). Stereo-SCIDAR: Instrument and First Commissioning Results. Messenger (Los Angeles, Calif. Online), 166, 41-46

Turbulence velocity profiling for high sensitivity and vertical-resolution atmospheric characterization with Stereo-SCIDAR (2016)
Journal Article
Osborn, J., Butterley, T., Townson, M., Reeves, A., Morris, T., & Wilson, R. (2017). Turbulence velocity profiling for high sensitivity and vertical-resolution atmospheric characterization with Stereo-SCIDAR. Monthly Notices of the Royal Astronomical Society, 464(4), 3998-4007. https://doi.org/10.1093/mnras/stw2685

As telescopes become larger, into the era of ∼40 m Extremely Large Telescopes, the high-resolution vertical profile of the optical turbulence strength is critical for the validation, optimization and operation of optical systems. The velocity of atmo... Read More about Turbulence velocity profiling for high sensitivity and vertical-resolution atmospheric characterization with Stereo-SCIDAR.

Online estimation of the wavefront outer scale profile from adaptive optics telemetry (2016)
Journal Article
Guesalaga, A., Neichel, B., Correia, C., Butterley, T., Osborn, J., Masciadri, E., …Sauvage, J. (2017). Online estimation of the wavefront outer scale profile from adaptive optics telemetry. Monthly Notices of the Royal Astronomical Society, 465(2), 1984-1994. https://doi.org/10.1093/mnras/stw2548

We describe an online method to estimate the wavefront outer scale profile,L0(h), for very large and future extremely large telescopes. The stratified information on this parameter impacts the estimation of the main turbulence parameters [turbulence... Read More about Online estimation of the wavefront outer scale profile from adaptive optics telemetry.

Turbulence profiling for adaptive optics tomographic reconstructors (2016)
Presentation / Conference Contribution
Laidlaw, D. J., Osborn, J., Wilson, R. W., Morris, T. J., Butterley, T., Reeves, A. P., Townson, M. J., Gendron, É., Vidal, F., & Morel, C. (2016, July). Turbulence profiling for adaptive optics tomographic reconstructors

Final two-stage MOAO on-sky demonstration with CANARY (2016)
Presentation / Conference Contribution
Gendron, E., Morris, T., Basden, A., Vidal, F., Atkinson, D., Bitenc, U., Buey, T., Chemla, F., Cohen, M., Dickson, C., Dipper, N., Feautrier, P., Gach, J.-L., Gratadour, D., Henry, D., Huet, J.-M., Morel, C., Morris, S., Myers, R., Osborn, J., …Younger, E. (2016, July). Final two-stage MOAO on-sky demonstration with CANARY. Presented at SPIE Astronomical Telescopes + Instrumentation, Edinburgh

Experience with wavefront sensor and deformable mirror interfaces for wide-field adaptive optics systems (2016)
Journal Article
Basden, A., Atkinson, D., Bharmal, N., Bitenc, U., Brangier, M., Buey, T., …Younger, E. (2016). Experience with wavefront sensor and deformable mirror interfaces for wide-field adaptive optics systems. Monthly Notices of the Royal Astronomical Society, 459(2), 1350-1359. https://doi.org/10.1093/mnras/stw730

Recent advances in adaptive optics (AO) have led to the implementation of wide field-of-view AO systems. A number of wide-field AO systems are also planned for the forthcoming Extremely Large Telescopes. Such systems have multiple wavefront sensors o... Read More about Experience with wavefront sensor and deformable mirror interfaces for wide-field adaptive optics systems.

A tomographic algorithm to determine tip-tilt information from laser guide stars (2016)
Journal Article
Reeves, A., Morris, T., Myers, R., Bharmal, N., & Osborn, J. (2016). A tomographic algorithm to determine tip-tilt information from laser guide stars. Monthly Notices of the Royal Astronomical Society, 459(1), 333-341. https://doi.org/10.1093/mnras/stw622

Laser Guide Stars (LGS) have greatly increased the sky-coverage of Adaptive Optics (AO) systems. Due to the up-link turbulence experienced by LGSs, a Natural Guide Star (NGS) is still required, preventing full sky-coverage. We present a method of obt... Read More about A tomographic algorithm to determine tip-tilt information from laser guide stars.

Observations of the dynamic turbulence above La Palma using Stereo-SCIDAR (2015)
Journal Article
Osborn, J., Butterley, T., Perera, S., Fohring, D., & Wilson, R. (2015). Observations of the dynamic turbulence above La Palma using Stereo-SCIDAR. https://doi.org/10.20353/k3t4cp1131607

Stereo-SCIDAR is a generalised-SCIDAR instrument which is used to characterise the atmospheric optical turbu- lence in terms of strength (Cn2) and wind velocity profile using the triangulation technique and an optical binary star. Stereo-SCIDAR diffe... Read More about Observations of the dynamic turbulence above La Palma using Stereo-SCIDAR.

Atmospheric scintillation in astronomical photometry (2015)
Journal Article
Osborn, J., Föhring, D., Dhillon, V., & Wilson, R. (2015). Atmospheric scintillation in astronomical photometry. Monthly Notices of the Royal Astronomical Society, 452(2), 1707-1716. https://doi.org/10.1093/mnras/stv1400

Scintillation noise due to the Earth's turbulent atmosphere can be a dominant noise source in high-precision astronomical photometry when observing bright targets from the ground. Here we describe the phenomenon of scintillation from its physical ori... Read More about Atmospheric scintillation in astronomical photometry.

Characterising atmospheric optical turbulence using stereo-SCIDAR (2015)
Journal Article
Osborn, J., Butterley, T., Föhring, D., & Wilson, R. (2015). Characterising atmospheric optical turbulence using stereo-SCIDAR. Journal of Physics: Conference Series, 595(1), Article 012022. https://doi.org/10.1088/1742-6596/595/1/012022

Stereo-SCIDAR (SCIntillation Detection and Ranging) is a development to the well known SCIDAR method for characterisation of the Earth's atmospheric optical turbulence. Here we present some interesting capabilities, comparisons and results from a rec... Read More about Characterising atmospheric optical turbulence using stereo-SCIDAR.

Error sources in SLODAR turbulence profile fitting (2015)
Journal Article
Butterley, T., Osborn, J., & Wilson, R. (2015). Error sources in SLODAR turbulence profile fitting. Journal of Physics: Conference Series, 595(1), Article 012006. https://doi.org/10.1088/1742-6596/595/1/012006

This paper discusses some of the main error sources that affect use of the Slope Detection and Ranging (SLODAR) technique to recover atmospheric turbulence profiles from Shack-Hartmann wavefront sensor data. The most significant factor we address her... Read More about Error sources in SLODAR turbulence profile fitting.

Scintillation Noise in Exoplanet Transit Photometry (2015)
Journal Article
Föhring, D., Wilson, R., Osborn, J., & Dhillon, V. (2015). Scintillation Noise in Exoplanet Transit Photometry. Journal of Physics: Conference Series, 595(1), Article 012010. https://doi.org/10.1088/1742-6596/595/1/012010

Transit photometry is a powerful technique for studying exoplanets. Transit observations from the ground of targets of magnitude V= 10 or brighter, however, are limited by scintillation noise due to Earth's atmosphere. Through turbulence profiling us... Read More about Scintillation Noise in Exoplanet Transit Photometry.

Characterising daytime atmospheric conditions on La Palma (2015)
Journal Article
Townson, M., Kellerer, A., Osborn, J., Butterley, T., Morris, T., & Wilson, R. (2015). Characterising daytime atmospheric conditions on La Palma. Journal of Physics: Conference Series, 595, Article 012035. https://doi.org/10.1088/1742-6596/595/1/012035

Day-time turbulence profiles are important for the next generation of Solar Telescopes, which will be equipped with multi conjugate adaptive optics systems. We measured daytime turbulence profiles above La Palma from 17th to 19th September 2013 using... Read More about Characterising daytime atmospheric conditions on La Palma.

Scintillation correction for astronomical photometry on large and extremely large telescopes with tomographic atmospheric reconstruction (2014)
Journal Article
Osborn, J. (2015). Scintillation correction for astronomical photometry on large and extremely large telescopes with tomographic atmospheric reconstruction. Monthly Notices of the Royal Astronomical Society, 446(2), 1305-1311. https://doi.org/10.1093/mnras/stu2175

We describe a new concept to correct for scintillation noise on high-precision photometry in large and extremely large telescopes using telemetry data from adaptive optics (AO) systems. Most wide-field AO systems designed for the current era of very... Read More about Scintillation correction for astronomical photometry on large and extremely large telescopes with tomographic atmospheric reconstruction.