Vladimir Frolov (Centro Fermi) On behalf EEE-TO group

Experimental activities: The system for testing the MRPC in the Torino INFN laboratory has been fully mounted and checked; The cosmic ray telescope in the physics laboratory (on first floor of the building) of the Alessandro Volta Lyceum has been mounted and tested; The noise characteristics and efficiencies of all the 9 MRPC, presently available in Torino, have been determined; New data readout and storage software has been developed on the basis of the free object-oriented library for analysis and presentation of physical data (ROOT framework). The programs developed are functional both in the LINUX and Windows XP operating systems. The format of data, obtained during our statistics collection, is fully compatible with the format of data, obtained with the aid of software based on the LabView system developed at CERN for the EEE project.

Results of the MRPCs tests in the INFN laboratory: In conditions of good grounding of the detector and electronics we obtained a very low noise level and were able to debug our software and adjust the electronics. On the pictures one can see the efficiency and noise vs. HV.

The results of MRPC tests on first floor of the “Alessandro Volta” lyceum: In May of 2007 a cosmic ray telescope was installed in the physics laboratory of the Lyceum and tests were performed of the efficiencies and noise characteristics of the chambers. The operation of the software and hardware systems was tested in real conditions. The said test has revealed it necessary to realize high-quality grounding in the laboratory of the Lyceum.

Local network Data Server Data Storage C l i e n t s VME crate U S B Internet Scheme of our DAQ System High priority Low priority

Why do we use our own software? From the very beginning, owing to the absence of part of the electronics, we could not start testing the chambers using the official software, based on LABVIEW and developed at the CERN laboratory especially for the EEE project. For this reason we had to develop a DAQ system based on the ROOT library for analysis and presentation of physical data. As electronics arrived in our laboratory, this program underwent transformation into a full-scale DAQ system, completely compatible, at a hardware and data format level, with the official DAQ software. We decided that since an independent DAQ version could not hinder development of the EEE project and, also, since open source software is more flexible and friendly to experimental physicists, to further develop our own software. Moreover, since the LINUX operating system requires much working experience with computers, our DAQ system has been made to operate on computers with Windows XP, too.

The monitoring data presented in this figure reveal the lower chamber to have problems with both noise and gas, which results in the time distribution of hits being shifted to the right and in the multiplicity measured being very high. One of the causes of noise consists in the presence of a RAI transmission antenna in the near vicinity of the school (within 300 m). At present we are dealing with this problem and hope to resolve it in the nearest future.

Hit profiles for each chamber of the telescope. These pictures demonstrate the small time discrepancy for each FE channel, which will be taken into account in the future analysis. The lower chamber can be seen to exhibit a lower efficiency (in the lower part of the figure), possibly due to gas leakage.

In our data monitoring program we seek the x and y coordinates of each cluster and calculate the track of the particle by a linear fit. In the calculation we apply the following selection rules: Only 1 chamber is permitted to exhibit a over one cluster of hits; |(X top -X bottom )/2-X middle | ≤ 2 |(t top -t bottom )/2-t middle |≤ 2 ns A cluster that does not satisfy all these conditions is considered to be caused by noise and is discarded by the program. By applying these rules we were able to study about 85% of the events in the run.

This figure presents the noise distribution revealing the level of noise in the lower chamber to exceed the noise in the other chambers by a factor of 5. This confirms the necessity of careful grounding of the chambers.

Angular distributions of tracks obtained in the on-line operating mode by our monitoring program. The small asymmetry in the azimuthal (middle figure) angles may be explained by imperfect synchronization of the channels and by gas problems.

3D event viewer allows us to see tracks in real-time mode.

Photos showing the telescope installed in the Alessandro Volta school. Our group designed the “Cosmic Box”, which comprises two plastic scintillation counters and permits students to observe fluxes (depending on the inclination angle of the device) of cosmic rays passing through the box. Above one can see the readout electronics with the low- voltage supply (blue box) especially developed for the EEE project and permitting to set the high voltage on the chambers either manually or via the I2C interface.

D'AZEGLIO – FERRARIS = 1,0km D'AZEGLIO – VOLTA = 1,1km FERRARIS - VOLTA = 1,3km FERRARIS – INFN = 5,0km GIOBERTI - INFN = 6,8km D'AZEGLIO – INFN = 5,3km VOLTA - INFN = 6,2km This aerial-view map from Google shows the Torino sites, where telescopes are to be installed. Distances between cosmic-ray telescopes in Torino: The Giordano Bruno and Gioberti schools have also expressed their intention of taking part in the EEE project

Conclusion: All 9 MRPCs have been tested, 3 chambers have to be repaired; A new DAQ system has been developed and tested by our group; A 6+1 channel LV power supply has been developed (its I2C interface has to be tested, and the relevant software has to be developed); A compact trigger system (“Cosmic Box”) for testing the chambers and for demonstration of cosmic ray fluxes has been developed for the EEE project at the Torino INFN laboratory; 1 cosmic-ray telescope has been installed and tested in the A.Volta school. A RAI transmission antenna is located in the vicinity of the school, which seriously interferes with the operation of our telescope. We hope to resolve this problem in the near future.