ARGO-YBJ: Italy (INFN) - China (CAS) collaboration
Collaboration:
Location: Yangbajing Cosmic Ray Laboratory, 4300 m a.s.l., Tibet (China)
1. Goal of the experiment
The ARGO-YBJ experiment is devoted to the search of cosmic ray sources by means of the observation of galactic and extragalactic neutral and charged radiation in the energy range 100 GeV - 1000 TeV with a detector based on Resistive Plate Chambers (RPC's) covering an area of 6500 m2 and providing a detailed space-time picture of the cosmic ray shower front. The detector is under construction at the Yangbajing Cosmic Ray Laboratory.
2.
Activities during the 2002
The following achievements have been obtained:
Construction of 457 RPCs (76%) Comment: the
assembling line at the provider has been stopped for about 3
months to solve technical problems related to the bakelite
sheets.
Installation of 40 Clusters (67%). Comment: about 10% of the RPCs shipped to Yangbajing broke down on the way. All the other chambers,successfully tested, have been installed.
36 Clusters connected to the electronics but only 16 of
them put in data taking (32%). Comment: we had some DAQ problems
which prevented us from increasing the trigger rate.
Milestones 2003
Construction of 600 RPCs | 31-12-2003 |
100 clusters installed by the end of 2003 | 31-12-2003 |
50 clusters in operation with electronics | 31-12-2003 |
36 clusters in data taking for physics run | 31-12-2002 |
3. INFN contribution to the experiment in terms of manpower and financial support
Manpower:
54 researchers (37 FTE), 4 technologists (2 FTE), 8 technicians (4.5 FTE) plus support from the mechanics and electronics workshops of Napoli and Roma-2.
Budget for the Year 2003: 4.1% of the CSNII total budget
4. Publications in refereed journal: 2
5. Conference talks: 1
6. Number of undergraduate and doctoral thesis on the experiment:
7. Leadership roles and primary responsibilities in the experiment
Lecce: Local Station electronics and trigger.
Napoli: DAQ, gas distribution system, analog read-out, trigger.
Roma-2: Front-End electronics, detector control system
Roma-3: Detector assembling, experiment layout, HV system, trigger distribution.
8. Innovative instruments
The ARGO-YBJ experiment has developed
Many of the technical solutions could be of general interest
for experiments aiming to fully exploit the RPCs performance
9. Competing experiments
A similar approach to the g -astronomy ("full coverage" detector at high altitude, large field of view, ~ 100 % duty cycle) is already operating (MILAGRO (USA), 2600 m a.s.l., 4800 m2 water pool instrumented with PM tubes + array). The performance of ARGO-YBJ is expected to be definitely better, due to the high space-time granularity as well as to the higher elevation of the experimental site. However, a fast completion and commissioning of the detector is needed.
10. International committee which has reviewed the experiment
The ARGO-YBJ project has been examined and approved by the
INFN Committee II and by the CAS Scientific Committee.