2006 Zeldovich Medal Winners

.

The Zeldovich Medals are given to young scientists who have demonstrated excellence and achievement in the field of research . They are conferred by COSPAR and the Russian Academy of Sciences and honour the memory of distinguished astrophysicist Academician Yakov B. Zeldovich.

This year's winners from Imperial College are Dr Marina Galand and Dr Diana Shaul who won the medal for excellence and achievement in their field of research. They will be presented with the medals at the awards ceremony in Beijing, China, on the 17^th July.

Dr Diana Shaul

Below is a description of Dr Shaul's research

"I have been working on the LISA (Laser Interferometer Space Antenna) project, a planned ESA-NASA space mission. LISA aims to sense "gravitational waves", ripples in space-time predicted by Einstein's theory of General Relativity. LISA will test General Relativity - a cornerstone of modern physics - with unprecedented precision, and become a unique observatory, opening a new window onto the astrophysical events that shape our Universe.

My research focuses on eliminating noise and artifacts associated with electrostatic charging, that could otherwise confuse LISA's search for gravitational waves. LISA will consist of three spacecraft, orbiting the Sun in a triangular formation. At the heart of each spacecraft will be small, isolated 'test masses'. A passing gravitational wave will stretch the space between one pair of distant test masses, whilst compressing the space between another. Laser light is effectively reflected between the test masses on distant spacecraft, to form essentially a giant interferometer in space, to measure the relative changes in the separations between the test masses. As the distance changes associated with the passage of a gravitational wave are very small, spurious test mass motions must be suppressed to unprecedented levels for LISA's goals to be achieved.

Arguably the largest source of spurious motions is non-gravitational, electromagnetic forces that arise due to test mass charging, caused by LISA's bombardment with charged solar and galactic cosmic ray particles. The build up of charge will cause these forces to steadily increase, resulting in 'coherent Fourier signals' in the data. These are particularly troublesome as, unlike random noise, they do not decrease over time and within a few hours can become large enough to mask and confound identifications of gravitational waves. My work has highlighted this problem and identified different approaches to minimise its effect on LISA.

I have also modelled the electrostatic environment of the test mass using the finite element method. This enabled me to provide improved estimates of the charging disturbances, and is being used in a model of spacecraft operations. It is notoriously difficult to estimate the accuracy of finite element models, and in the course of my research, I developed a novel and efficient way of doing this, which I was able to apply to the project.

The sheer scope the LISA mission means that one individual cannot work alone and I am privileged to be part of a first class international team, which includes a number of members from Imperial's Astrophysics group, whom I would like to thank for their continued support. "

Dr Marina Galand

Professor Peter Cargill, head of the SPAT group, had this to say about Marina's achievment:-

"The space and atmospheric physics group is delighted with Marina's award. Since joining the group last summer as part of a new initiative in planetary science, Marina has contributed greatly to our efforts in this field. The award of the Zeldovich medal is a well-deserved recognition of the achievements in her career up to this time."

Below is a description of Dr Galand's research

The research I have been conducting belongs to the field of space physics. I have focused on the contribution of energy sources, such as solar radiation and auroral energetic particles, upon the atmospheres of planets and moons. Solar system bodies I have studied include Earth and Saturn's moon, Titan. The latter is the only moon in the Solar System to sustain a permanent, thick atmosphere. This atmosphere made primarily of nitrogen may have similarities with the primordial terrestrial atmosphere. The Cassini spacecraft currently orbiting around Saturn is regularly flying through Titan's atmosphere. It has provided us with a wealth of in situ observations - including dataset from the magnetometer instrument for which Imperial College (Prof. M. Dougherty) is the PI. These observations have been revealing to us Titan's complex interaction with the magnetic environment imposed by Saturn, exciting our appetite for its further understanding. While modeling is the prime approach I have been using, observational campaigns and analysis of data from space missions such as Cassini have been an enriching complement to my research.