MRPC with eco-friendly gas

The Multigap Resistive Plate Chambers (MRPC) are used as a timing detector in several particle physics and cosmic ray experiments. The gas mixture of MRPC at current experiments is a mixture containing C2F4H2 and in some cases SF6. C2F4H2 and SF6 have a Global Warming Potential (GWP) of 1430 and 23900 respectively, therefore they are classified as greenhouse gases. The studies to reduce the amount of emission of the greenhouse gas in high energy experiments are underway; the present contribution has been performed as part of this effort. The results have been obtained from the beam test of a small MRPC which has 6 gaps of 220 mu m and a sensitive area of 20 x 20 cm(2). It has been operated with the ecological HFO-1234ze gas (C3F4H2), and with the C2F4H2/SF6 mixture. We have found that the ecological gas can substitute for the C2F4H2-based gas mixture without significantly compromising the current level of performance.