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The LOIS project Part of the Nature OnLine collaboration

The LOIS project Part of the Nature OnLine collaboration. Bo Thidé Swedish Institute of Space Physics, IRF, Uppsala, Sweden With contributions from the LOIS OAM/radio topology collaboration.

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The LOIS project Part of the Nature OnLine collaboration

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  1. The LOIS projectPart of the Nature OnLine collaboration Bo Thidé Swedish Institute of Space Physics, IRF, Uppsala, Sweden With contributions from the LOIS OAM/radio topology collaboration

  2. LOIS vector radio facilities in southern Sweden and labs in Uppsala for OAM radio and radar system assessments The control room at the LOIS Test Station Risinge/Växjö. Computer cluster (funded by two Shared University Research grants from IBM) Radio Sweden’s transmitter located about 100 km south of the Växjö LOIS test station and 100 km south-west of the Ronneby prototype station site. Will be used for space radar tests. 9m×8m×6m antenna chamber, Ångström Lab, Uppsala Magnetometer, LOIS Test Station, Risinge/Växjö

  3. LOIS radio idea: Sample the entire field vectors in time and space (LOIS stn true superset of LOFAR stn)

  4. LOIS prototype station under construction in RonnebyTo be augmented by two outer, concentric rings, with 16 and 24 radio units, respectively, for a total of 48 units with three dipoles each (consortium funding)

  5. LOIS prototype station site at Angelskog, RonnebyLeft photos taken 21 December, 2007, at 14:00 local time. Right photo from eniro.se REAL Seminar, BTH, Ronneby, 23 January, 2009

  6. LOIS prototype station centre at BTH in Ronneby Eight ex-SWEGRID PC blades provided by UPPMAX, Uppsala University (SNIC/VR) 21/101 Gbit/s light path provided by the Blekinge Institute of Technology (BTH) Swedish LOFAR Science Meeting, Stockholm, 15 January, 2009

  7. Use three orthogonal electric and magnetic antennas to sample the entire EM field vector To be tried at EISCAT, 2010

  8. 3D vector sensing allows new radio diagnostics Better SNR, polarisation in real time, DOA,… Click on pictures for animation! Real data from a real, live outdoor vector receiver at Ångström Lab in Uppsala. On line since 2003. Instantaneous wave polarisation from one single vector antenna Vector coherency gives superior SNR relative to conventional scalar intensity

  9. 2D LOFAR/SKA-type interferometers exhibit polarisation aberration. 3D interferometers do not Swedish LOFAR Science Meeting, Stockholm, 15 January, 2009

  10. Close collaboration with IBM Research, NY, on the analysis of streaming data from digital radio sensors

  11. Imparting OAM onto a light beam The generation of beams carrying OAM proceeds thanks to the insertion in the optical path of a phase modifying device which imprints a certain vorticity on the phase distribution of the incident beam. Fork hologramsare an example of such devices. If the hologram presents Nbifurcations, then at the m-th diffraction order it imposes a OAM value equal to N mħ(Vaziriet al.2002). On-axis off-axis spectrum of OAM Spiral Phase Plate s= total thickness of the plate,Δn= difference of refraction indices.

  12. Properties of radio OAM generated by antenna arrays Thidé et al., Phys. Rev. Lett., 99, 087701, 2007

  13. The OAM radio results agree with theory Theory predicts that a circular polarised radio beam in a pure OAM eigenstate with azimuthal phase dependence exp(ilφ), frequency ω, and energy H, should have a total angular momentum component JzEM = lH/ωalong the z (beam) axis.

  14. Exchange of OAM between plasma and radio/radar Brillouin = ion line Raman = plasma line

  15. Improving resolving power of telescopes by one order of magnitude The James Webb Space Telescope Credit: ESA (C. Carreau) Super Resolution with OVs in diffraction-limited telescopesand other optical instruments

  16. Field vector sensing means total configurability The ultimate radio coronagraph!

  17. OV manipulation for detection at the telescope.ProducingOpticalVorticeswithstarlight andthe problem of atmospheric seeing 1 Uppsala, Celsius Workshop 2010

  18. Optical Vortices and Stellar Coronagraphy 2 Picturestaken @theLyotmask position oftwoartificialstarswithincreasingangulardistance OVC Lyot stop ordinary Lyot stop We place the phase mask in the focal plane of the telescope to generate anℓ = 2 OV with the on-axis star, then followed by a ring-shaped Lyot stop to block that vortex. The off-axis secondary star light, instead, will pass through the Lyotmask without being affected. 1 2 3 4 Uppsala, Celsius Workshop 2010

  19. First OVC @ T122 Asiago telescope 2-3 /D (a) 2.8x10-10 (b) 2-8 /D (a) 9.3x10-11 (b) 4-5 /D (a) 6.4x10-11 (b) Theoretical contrast for a monochromatic source (b) versus the separation (a). Sufficient resolution for direct detection of extra-solar planets.

  20. Supporting Sardinia Radio Telescope for OAM

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