Speaker
Description
Precise measurement of the composition of cosmic rays in the energy range of $10^{16}$ to $10^{18}$ eV may settle the long standing issue of the galactic or extra galactic origin of these particles in the energy region. Ground-based experiments mostly rely on the determination of the depth of air shower maximum ($\rm X_{max}$) to measure the type of cosmic-ray particle. One efficient technique is to record images of the air-shower development using fluorescence telescopes. An alternative technique that has made significant advances in recent years is to measure the radio emission from air showers. Methods for $\rm X_{max}$ determination in radio detection technique include fitting a two dimensional radio intensity profile observed at the ground with Monte Carlo showers which is computationally quite expensive, and others that are based on parameterization obtained from simulation.
In this contribution, we propose a new method to determine $\rm X_{max}$ purely from the observed data with minimal input from simulation. The method involves geometrical reconstruction of the longitudinal profile of air shower by backtracking radio signals observed at the ground to their emission points. The method will allow an event-by-event reconstruction of $\rm X_{max}$ without uncertainty and bias inherited from simulation unlike other existing methods. Details of the method and some preliminary results based on simulated data will be presented.
