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This Letter reports results from the NEMO-3 experiment based on an exposure of 1275 days with 661g of 130Te in the form of enriched and natural tellurium foils. The double beta decay rate of 130Te is found to be greater than zero with a significance of 7.7 standard deviations and the half-life is measured to be T1/2 = (7.0 +/- 0.9(stat) +/- 1.1(syst)) x 10^{20} yr. This represents the most precise measurement of this half-life yet published and the first real-time observation of this decay.

Proton scattering in some water and tissue equivalent phantom materials was measured to evaluate their simulation accuracy of water and respective human biological tissues. The measurements were performed on the medical facility of the ITEP synchrotron, proton energy was 219 MeV, a narrow beam was formed by a 3 mm collimator. A stack of plastic slabs was set closely to the collimator hole as a scatterer. Three types of Plastic Water (PW, PW LR and PW DT), lung, cortical bone, adipose and muscle plastics (CIRS Inc., USA) were used in the experiments as the substitutes under investigation and liquid water and PMMA slabs as reference materials. Dose (intensity) profiles were measured for each sample by two orthogonal strips of the Gafchromic EBT film. A total thickness of the plastic slab was from 4 to 16 cm depending on the material. The Gafchromic film response nonlinearity was taken into account by an additional calibration vs. absorbed dose in a wide proton beam, the temporal irradiation-to-scanning dependence was also accounted. The central part of each angular distribution was fitted by the Gaussian function and compared with the respective parameters calculated for the simulated medium by Monte Carlo technique with the IThMC code., Comment: 7 pages, 4 figures

Tissue and water equivalence of some phantom materials originally developed for conventional radiation therapy was investigated on the ITEP medical proton beam facility. The proton CSDA range in three variants of Plastic Water, lung, adipose, muscle and compact bone substitute materials (CIRS Inc., USA) was measured by a silicon diode as well as the residual proton range in liquid water after passing a slab of each material under investigation. In addition, the proton range in five materials of known elemental composition was calculated by Monte Carlo technique. The obtained results were compared with reference data from ICRU report 49 for respective biological tissues and water. A total uncertainty of the proton range ratios was estimated to be from 0.9 to 1.5% (1SD). Within these uncertainties, Plastic Water, Plastic Water LR, Plastic Water DT, muscle and compact bone demonstrated a good agreement with the reference data. The range in adipose and lung substitutes is a few percents lower than that in the respective tissues., Comment: 8 pages, 2 figures. Presented on PTCOG 48, Heidelberg, September 28th - October 3rd, 2009

The possibility to probe new physics scenarios of light Majorana neutrino exchange and right-handed currents at the planned next generation neutrinoless double beta decay experiment SuperNEMO is discussed. Its ability to study different isotopes and track the outgoing electrons provides the means to discriminate different underlying mechanisms for the neutrinoless double beta decay by measuring the decay half-life and the electron angular and energy distributions., Comment: 17 pages, 14 figures, to be published in E.P.J. C

The development of BiPo detectors is dedicated to the measurement of extremely high radiopurity in $^{208}$Tl and $^{214}$Bi for the SuperNEMO double beta decay source foils. A modular prototype, called BiPo-1, with 0.8 $m^2$ of sensitive surface area, has been running in the Modane Underground Laboratory since February, 2008. The goal of BiPo-1 is to measure the different components of the background and in particular the surface radiopurity of the plastic scintillators that make up the detector. The first phase of data collection has been dedicated to the measurement of the radiopurity in $^{208}$Tl. After more than one year of background measurement, a surface activity of the scintillators of $\mathcal{A}$($^{208}$Tl) $=$ 1.5 $\mu$Bq/m$^2$ is reported here. Given this level of background, a larger BiPo detector having 12 m$^2$ of active surface area, is able to qualify the radiopurity of the SuperNEMO selenium double beta decay foils with the required sensitivity of $\mathcal{A}$($^{208}$Tl) $<$ 2 $\mu$Bq/kg (90% C.L.) with a six month measurement., Comment: 24 pages, submitted to N.I.M. A

Using 9.4 g of Zr-96 and 1221 days of data from the NEMO-3 detector corresponding to 0.031 kg yr, the obtained 2vbb decay half-life measurement is [2.35 +/- 0.14(stat) +/- 0.16(syst)] x 10^19 yr. Different characteristics of the final state electrons have been studied, such as the energy sum, individual electron energy, and angular distribution. The 2v nuclear matrix element is extracted using the measured 2vbb half-life and is 0.049 +/- 0.002. Constraints on 0vbb decay have also been set., Comment: Published in Nucl.Phys.A (10 pages, 10 figures)

In the double beta decay experiment NEMO~3 a precise knowledge of the background in the signal region is of outstanding importance. This article presents the methods used in NEMO~3 to evaluate the backgrounds resulting from most if not all possible origins. It also illustrates the power of the combined tracking-calorimetry technique used in the experiment., Comment: 32 pages, 23 figures, submitted to NIM A

NEMO 3 is a double beta decay experiment. A part of low background data was analysed, preliminary result on bb2nu decay of 130Te obtained: T_{1/2} = 7.6 \+- 1.5(stat) +- 0.8(syst) * 10^{20} y$. No bb0nu signal was observed: T_{1/2}^{0\nu}(100Mo) > 5.8 *10^{23} y and T_{1/2}^{0\nu}(82Se) > 2.1 * 10^{23} y (90% C.L.). SuperNEMO project R&D has started., Comment: Contribution paper for SUSY07 proceedings, 4pages, 4 figures

The double beta decay of 100Mo to the 0^+_1 and 2^+_1 excited states of 100Ru is studied using the NEMO 3 data. After the analysis of 8024 h of data the half-life for the two-neutrino double beta decay of 100Mo to the excited 0^+_1 state is measured to be T^(2nu)_1/2 = [5.7^{+1.3}_{-0.9}(stat)+/-0.8(syst)]x 10^20 y. The signal-to-background ratio is equal to 3. Information about energy and angular distributions of emitted electrons is also obtained. No evidence for neutrinoless double beta decay to the excited 0^+_1 state has been found. The corresponding half-life limit is T^(0nu)_1/2(0^+ --> 0^+_1) > 8.9 x 10^22 y (at 90% C.L.). The search for the double beta decay to the 2^+_1 excited state has allowed the determination of limits on the half-life for the two neutrino mode T^(2nu)_1/2(0^+ --> 2^+_1) > 1.1 x 10^21 y (at 90% C.L.) and for the neutrinoless mode T^(0nu)_1/2(0^+ --> 2^+_1) > 1.6 x 10^23 y (at 90% C.L.)., Comment: 23 pages, 7 figures, 4 tables, submitted to Nucl. Phys