1 1. Title: Characterisation of elastic and acoustic properties of an agar-based tissue 1 mimicking material. 2 Authors: 3 1. M.P.Brewin, Blizard Institute, Barts and The London School of Medicine and Dentistry, 4 Queen Mary University of London, London, UK 5 2. M.J.Birch, Clinical Physics, Barts Health NHS Trust, 56-76 Ashfield Street, London, UK 6 3. D.J.Mehta, Blizard Institute, Barts and The London School of Medicine and Dentistry, 7 Queen Mary University of London, London, UK 8 4. J.W.Reeves, Clinical Physics, Barts Health NHS Trust, 56-76 Ashfield Street, London, 9 UK 10 5. S.Shaw, BICOM (Brunel Institute of Computational Mathematics) and Mathematics, 11 Brunel University, UK 12 6. C. Kruse, BICOM (Brunel Institute of Computational Mathematics) and Mathematics, 13 Brunel University, UK 14 7. J.R. Whiteman, BICOM (Brunel Institute of Computational Mathematics) and 15 Mathematics, Brunel University, UK 16 8. S.Hu, Center for Research in Scientific Computation, North Carolina State University, 17 Raleigh, NC, USA 18 9. Z.R.Kenz, Center for Research in Scientific Computation, North Carolina State 19 University, Raleigh, NC, USA 20 10. H.T.Banks, Center for Research in Scientific Computation, North Carolina State 21 University, Raleigh, NC, USA 22