The differential cross section for the reaction p(γ,ηp) has been measured from threshold to 1100 MeV photon laboratory energy. For the first time, the region of the S11(1535) resonance is fully ...covered in a photoproduction experiment and will allow a precise extraction of its parameters at the photon point. These high precision data together with the already measured beam asymmetry data will provide stringent constraints on the extraction of new couplings of baryon resonances to the η meson.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The double pi(0) photoproduction off the proton has been measured in the beam energy range of 0.65-1.5 GeV. The total and differential cross sections and the Sigma beam asymmetry were extracted. The ...total cross section measured for the first time in the third resonance region of the nucleon shows a prominent peak. The interpretation of these results by two independent theoretical models infers mostly the selective excitation of P11- and D13-nucleon resonances.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UM
We present an overview of the radon surveys at Stromboli island starting from the 2002, with the aim to better understand the relation between in-soil radon degassing and change in volcanic activity. ...Radon measurements were performed by means of different, passive, methodologies. By using a radon network of 21 sampling sites, placed in the NE sector of the island, we effected periodic surveys by means of two manually techniques. Track-etch detectors and EPERM electrets allowed us to construct a continuous time-series of radon measurements during the period 2002–2007 and to recognize the short-time variations. Radon activity shows, by means of EPERM® electrets, a wide range of values, from 0.3 to 50 kBq/m3. These data confirm the role of the local effects on the in-soil radon emissions and show that the structural alignments represent a preferential pathways for the radon migration from soil to air. Prom the 2007 we developed two real-time multiparametric, fully automated stations where the measurements of radon activity, acquired every 15 minutes, are correlated with the soil temperature and atmospheric pressure data. The first results show the important role of the atmospheric factors (e.g. soil temperature) in the acquired radon measurements.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
In the present work we report on a new measurement of resonance strengths ωγ in the reaction 25Mg(p, γ)26Al at Ecm=92 and 189 keV. This study was performed at the LUNA facility in the Gran Sasso ...underground laboratory using a 4π BGO summing crystal. For the first time the 92 keV resonance was directly observed and a resonance strength ωγ=(2.9±0.6)×10−10 eV was determined. Additionally, the γ-ray branchings and strength of the 189 keV resonance were studied with a high resolution HPGe detector yielding an ωγ value in agreement with the BGO measurement, but 20% larger compared to previous works.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Neutron detection by large NaI crystal Lavagnoa, A; Gervinob, G
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
07/2016, Volume:
824
Journal Article
Peer reviewed
In present days new neutron detection methods are under developed due to the global shortage of super(3)He and the toxicity of BF sub(3). Neutrons can be indirectly detected by high-energy photons. ...The performance of a cylindrical NaI crystal, 4 in. diameter and 8 in. length as an indirect neutron detector has been investigated. Measurements were performed with super(252)Cf source with bare and shielded NaI detector. With a proper converter and moderator structure for the NaI detector, the detection efficiencies and the minimum detectable activities are improved, making the method very interesting for security applications. The indirect detection of neutrons by photons has several advantages. First, this method can in principle be suited by any gamma spectrometer with only slight modifications that do not compromise with its gamma spectrometry measurements. Second, fission neutron sources and neutron generators can be discriminated thanks to their different gamma energy spectra, a discrimination easily done by a NaI spectrometer.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
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