| M. Campbell, M. Chefdeville, P. Colas, A.P. Colijn, A. Fornaini, Y. Giomataris, H. Van der Graaf, E.H.M. Heijne, P. Kluit, X. Llopart, J. Schmitz, J. Timmermans,J.L. Visschers |
A small drift chamber was read out by means of
a MediPix2 readout chip as direct anode.
A Micromegas foil was placed 50 $\\mu$m above the chip, and electron multiplication
occurred in the gap. With a He/Isobutane 80/20 mixture, gas multiplication factors
up to tens of thousands were achieved, resulting in an efficiency for detecting
single electrons of better than 90\\% . We recorded many frames containing 2D
images with tracks from cosmic muons.
Along these tracks, electron clusters were observed, as well as $\\delta$-rays. |
