The analysis of the 'energetic' halo in a X-ray calorimeter

In the emulsion chamber which are exposed at mountain altitudes a phenomeno n called (optical) halo can be observed in the cores of high energy extensi ve air showers. A 'halo' is defined as an area of a few mm(2) of high optic al density, which happens when a great number of charged particles go throu gh a X-ray emulsion. In the present paper it is proposed to use a simple pa rameter: 'energetic' halo. It is shown that there is an evident correlation between the optical halo (observed in X-ray film) of the area exceeding 80 mm(2), the area of which Mras calculated by the use of the isodense method and the energetic halo.