DAMA

Collaboration:

Location of the experiment: Gran Sasso National Laboratory (LNGS)

National Responsible: R. Bernabei (Roma2)

1. Goal of the experiment

The DAMA experiment is an observatory for rare processes such as: i) Dark Matter particles investigation;   ii) charge non-conserving (CNC) processes as electron decays in different channels, CNC electron capture in different isotopes; iii) nucleon and di-nucleon decay into invisible channels, in different isotopes; iv) solar axions search; v) neutral SIMPs and neutral nuclearites search; vi) bb decay processes in different isotopes.

More on the experiments...

2.

Activities during 2002 

The main goals achieved in the given period are:

~100 kg NaI(Tl) set-up

The LIBRA (Large sodium Iodide Bulk for RAre processes; ~250 kg of highly radiopure NaI(Tl)) set-up

~6.5 kg LXe set-up

R&D set-up

miscellaneous

The following achievements have been obtained:

 

Milestones 2003

Tests and runs with the LIBRA set-up

31-12-2003

Analysis of the previously collected data

31-12-2003

Data taking with Xenon enriched either in 129Xe or in 136Xe and related data analyses

31-12-2003

Data taking with the R&D set-up using various scintillators

31-12-2003

3. INFN contribution to the experiment in terms of manpower and financial support

4. Number of publications in refereed journals (in 2002): 7

5. Number of talks to conferences (in 2002): 13

6. Number of undergraduate and doctoral thesis on the experiment:

3 doctoral thesis in progress

7. Leadership roles and primary responsibilities of the experiment

8. Innovative instruments

Development of radiopure detectors, PMTs and overall set-ups.

9. Competing experiments

• As regards the 100 kg NaI(Tl) set-up, we recall that no other set-up with similar features (well known technique, radiopurity, exposed mass, complete monitoring and control of the running parameters, energy threshold etc.) is available to effectively search for the WIMP annual modulation signature. Moreover, it offers also the possibility to competitively exploit various other approaches (pulse shape discrimination of the electromagnetic background, search for exotic candidates etc.) and to investigate several other rare processes. This set-up has concluded the data taking in 2002.

• The new ~250 kg NaI(Tl) LIBRA set-up (whose installation has been largely performed since fall 2002) has even an increased competitiveness with respect to the previous 100 kg NaI(Tl) set-up discussed above.

• As regards the about 2 1 (i.e. about 6.5 kg) liquid Xenon (LXe) pure scintillator set-up, we recall that no other set-up with similar features (Kr-free Xenon gas enriched in particular isotopes, radiopurity, exposed mass, complete monitoring and control of the running parameters, energy threshold, effective far UV light collection, etc.) is available. This set-up has been periodically upgraded to further increase its performances and sensitivity. Since August 2000 it can be alternatively filled with Kr-free Xenon gas enriched at 99.5 % in 129Xe or at 68.8 % in 136Xe. The advantage to use Kr-free gases as well as the enrichements in these two isotopes can be easily inferred.

• As regards the CaF2(Eu), competitive results have been achieved with previous prototypes; future possibilities will be considered.

• The features of the “R&D” set-up assures the possibility of competitive small scale experiments; some of them are in progress.

• The low background Ge assures a continuum and effective work for material selection

10. International committee which has reviewed the experiment

The experiment is reviewed by the funding authorities of INFN and has also been periodically reviewed by the Scientific Committee of the LNGS. Chinese activity is funded by the National Natural Science Fund of China and Academia Sinica.