Jenifer Leech (née Wheildon Brown; later Haselgrove; 3 August 1930 – 13 March 2015) was a British physicist and computer scientist.
It formulates as the Eikonal equation and is only applicable under certain conditions including that the plasma is slowly varying; nevertheless it has enormous practical use in radio science.
Today Haselgrove's equations are widely used in scientific investigations involving radio propagation in slowly varying plasmas, and therefore have found much applicability in exploration and utilization of the Earth's ionosphere.
Here they have also been used to represent the radio propagation element of practical systems providing high frequency communication, direction finding and over-the-horizon radar.
Brian Haselgrove died in 1964, and Jenifer remarried to another British mathematician, John Leech, and took his surname.