Outputs (74)

Distortion of visible daytime multi-conjugate adaptive optics control (2024)
Presentation / Conference Contribution
Kongkaew, P., Morris, T. J., & Osborn, J. (2024, June). Distortion of visible daytime multi-conjugate adaptive optics control. Presented at Adaptive Optics Systems IX, Yokohama, Japan

Daytime optical observations, including solar telescope and free-space optical communication, experience strong turbulence and scintillation. These conditions cause control problems in Multi-Conjugate Adaptive Optics (MCAO). Considering an MCAO setup... Read More about Distortion of visible daytime multi-conjugate adaptive optics control.

Pre-distortion adaptive optics for optical feeder links: simulations and performance analyses (2024)
Journal Article
Hristovski, I. R., Osborn, J., Farley, O. J. D., Townson, M. J., Calvo, R. M., Femenía-Castella, B., Torres, J. S., Holzman, J. F., & Reeves, A. P. (2024). Pre-distortion adaptive optics for optical feeder links: simulations and performance analyses. Optics Express, 32(12), 20976-20991. https://doi.org/10.1364/oe.521494

Optical feeder links offer immense utility in meeting future communication demands—however, atmospheric turbulence limits their performance. This work targets this challenge through analyses of a bidirectional free-space optical communication (FSOC)... Read More about Pre-distortion adaptive optics for optical feeder links: simulations and performance analyses.

Exploring atmospheric optical turbulence: observations across zenith angles (2024)
Journal Article
Beesley, L. F., Osborn, J., Wilson, R., Farley, O. J. D., Griffiths, R., & Love, G. D. (2024). Exploring atmospheric optical turbulence: observations across zenith angles. Applied Optics, 63(16), E48. https://doi.org/10.1364/ao.519063

We present measurements of the atmospheric optical turbulence as a function of zenith angle using two identical instruments, Shack-Hartmann Image Motion Monitors (SHIMMs), to measure atmospheric parameters concurrently. One instrument was pointed nea... Read More about Exploring atmospheric optical turbulence: observations across zenith angles.

A comparison of next-generation turbulence profiling instruments at Paranal (2024)
Journal Article
Griffiths, R., Bardou, L., Butterley, T., Osborn, J., Wilson, R., Bustos, E., …Otarola, A. (2024). A comparison of next-generation turbulence profiling instruments at Paranal. Monthly Notices of the Royal Astronomical Society, 529(1), 320 - 330. https://doi.org/10.1093/mnras/stae434

A six-night optical turbulence monitoring campaign has been carried at Cerro Paranal observatory in February and March, 2023 to facilitate the development and characterisation of two novel atmospheric site monitoring instruments - the ring-image next... Read More about A comparison of next-generation turbulence profiling instruments at Paranal.

Continuous daytime and nighttime forecast of atmospheric optical turbulence from numerical weather prediction models (2023)
Journal Article
Quatresooz, F., Griffiths, R., Bardou, L., Wilson, R., Osborn, J., Vanhoenacker-Janvier, D., & Oestges, C. (2023). Continuous daytime and nighttime forecast of atmospheric optical turbulence from numerical weather prediction models. Optics Express, 31(21), 33850-33872. https://doi.org/10.1364/oe.500090

Future satellite-to-ground optical communication systems will benefit from accurate forecasts of atmospheric optical turbulence; namely for site selection, for the routing and the operation of optical links, and for the design of optical communicatio... Read More about Continuous daytime and nighttime forecast of atmospheric optical turbulence from numerical weather prediction models.

Optical sparse telescope arrays and scintillation noise (2023)
Journal Article
Hartley, K. E., Farley, O. J. D., Townson, M. J., Osborn, J., & Wilson, R. W. (2023). Optical sparse telescope arrays and scintillation noise. Monthly Notices of the Royal Astronomical Society, 526(1), 1235-1245. https://doi.org/10.1093/mnras/stad2835

Fresnel propagation of starlight after it passes through high altitude turbulence in the Earth’s atmosphere results in random fluctuations of the intensity at ground level, known as scintillation. This effect adds random noise to photometric measurem... Read More about Optical sparse telescope arrays and scintillation noise.

Line-of-sight optical Dome Turbulence Monitor (2023)
Journal Article
Osborn, J., & Alaluf, D. (2023). Line-of-sight optical Dome Turbulence Monitor. Monthly Notices of the Royal Astronomical Society, 525(2), 1936-1940. https://doi.org/10.1093/mnras/stad2428

Optical turbulence in the enclosure of a ground-based telescope can be a major contributor to the total optical turbulence strength and can therefore limit the precision of astronomical observations, in terms of angular resolution, or signal to noise... Read More about Line-of-sight optical Dome Turbulence Monitor.

Atmospheric optical turbulence analysis in London’s financial district (2023)
Presentation / Conference Contribution
Westerby-Griffin, L., Osborn, J., Farley, O. J. D., Griffiths, R., & Love, G. D. (2023, January). Atmospheric optical turbulence analysis in London’s financial district. Presented at Free-Space Laser Communications XXXV, San Francisco, United States

Atmospheric optical turbulence causes signal loses in laser propagation. Here we present vertical measurements of optical turbulence taken in London’s financial district. Additionally, we demonstrate a method of modelling atmospheric states in simula... Read More about Atmospheric optical turbulence analysis in London’s financial district.

The 24hSHIMM: a continuous day and night turbulence monitor for optical communications (2023)
Presentation / Conference Contribution
Griffiths, R., Osborn, J., Farley, O., Butterley, T., Townson, M., & Wilson, R. (2023, January). The 24hSHIMM: a continuous day and night turbulence monitor for optical communications. Presented at Free-Space Laser Communications XXXV, San Francisco, United States

We present the 24-hour Shack-Hartmann Image Motion Monitor (24hSHIMM), the first truly continuous, 24-hour optical turbulence monitor. Atmospheric optical turbulence is a significant limitation for free-space optical communications and other technolo... Read More about The 24hSHIMM: a continuous day and night turbulence monitor for optical communications.

First On-Sky Demonstration of a Scintillation Correction technique using Tomographic Wavefront Sensing (2023)
Journal Article
Hartley, K. E., Farley, O. J., Townson, M. J., Osborn, J., & Wilson, R. (2023). First On-Sky Demonstration of a Scintillation Correction technique using Tomographic Wavefront Sensing. Monthly Notices of the Royal Astronomical Society, 520(3), 4134-4146. https://doi.org/10.1093/mnras/stad420

Scintillation noise significantly limits high precision ground-based photometry of bright stars. In this paper we present the first ever on-sky demonstration of scintillation correction. The technique uses tomographic wavefront sensing to estimate th... Read More about First On-Sky Demonstration of a Scintillation Correction technique using Tomographic Wavefront Sensing.