Search results for "energy [photon]"
showing 10 items of 18329 documents
Decay studies of the long-lived states in Tl186
2020
Decay spectroscopy of the long-lived states in 186Tl has been performed at the ISOLDE Decay Station at ISOLDE, CERN. The α decay from the low-spin (2−) state in 186Tl was observed for the first time and a half-life of 3.4+0.5−0.4 s was determined. Based on the α-decay energy, the relative positions of the long-lived states were fixed, with the (2−) state as the ground state, the 7(+) state at 77(56) keV, and the 10(−) state at 451(56) keV. The level scheme of the internal decay of the 186Tl(10(−)) state [T1/2=3.40(9) s], which was known to decay solely through emission of 374-keV γ-ray transition, was extended and a lower limit for the β-decay branching bβ>5.9(3)% was determined. The extrac…
Exploring the boundaries of the nuclear landscape : α-decay properties of 211Pa
2020
Employing the recoil ion transport unit (RITU) and a fusion-evaporation reaction, the α decay of 211Pa has been identified via the implantation-decay correlation technique through observation of chains up to four consecutive decays. An α-particle energy and half-life of 8320(40) keV and 3.8+4.6−1.4 ms, respectively, were measured, corresponding to favored α decay. In addition, more precise α-decay properties of 212Pa and 213Pa were obtained due to accumulated statistics. The present data were compared to those predicted by selected atomic mass models and it was used to estimate the possibility of observing proton emission from these isotopes. peerReviewed
LBNO-DEMO (WA105): a large demonstrator of the Liquid Argon double phase TPC
2016
LBNO-DEMO (WA105) is a large demonstrator of the double phase liquid argon TPC intended to develop and test the main elements of the GLACIER-based design for the purpose of scaling it up to the 10–50 kton size needed for Long Baseline Neutrino Oscillation studies. The crucial components of the design are: ultra-high argon purity in non-evacuable tank, long drifts, very high drift voltages, large area Micro Pattern Gas Detectors, and cold preamplifiers. The active volume of the demonstrator is 6×6×6 m3 (approximately 300t). WA105 is under construction at CERN and will be exposed to charged particle beams (0.5-20 GeV/c) in the North Area in 2018. The data will provide the necessary calibratio…
Recent Progress in the WCLL Breeding Blanket Design for the DEMO Fusion Reactor
2018
The water-cooled lithium-lead (PbLi) breeding blanket is one of the candidate systems considered for the implementation in the European Demonstration Power Plant (DEMO) nuclear fusion reactor. This concept employs PbLi liquid metal as tritium breeder and neutron multiplier, water pressurized at 15.5 MPa as the coolant, and EUROFER as the structural material. The current design is based on the single module segment approach and follows the requirements of the DEMO-2015 baseline design. The module is constituted by a basic toroidal-radial cell that is recursively repeated along the poloidal direction where the liquid metal flows along a radial-poloidal path. The heat generated by the fusion r…
Seasonal Modulation of the $^7$Be Solar Neutrino Rate in Borexino
2017
We detected the seasonal modulation of the $^7$Be neutrino interaction rate with the Borexino detector at the Laboratori Nazionali del Gran Sasso in Italy. The period, amplitude, and phase of the observed time evolution of the signal are consistent with its solar origin, and the absence of an annual modulation is rejected at 99.99\% C.L. The data are analyzed using three methods: the sinusoidal fit, the Lomb-Scargle and the Empirical Mode Decomposition techniques, which all yield results in excellent agreement.
Rosenbluth separation of the $\pi^0$ Electroproduction Cross Section off the Neutron
2017
We report the first longitudinal/transverse separation of the deeply virtual exclusive $\pi^0$ electroproduction cross section off the neutron and coherent deuteron. The corresponding four structure functions $d\sigma_L/dt$, $d\sigma_T/dt$, $d\sigma_{LT}/dt$ and $d\sigma_{TT}/dt$ are extracted as a function of the momentum transfer to the recoil system at $Q^2$=1.75 GeV$^2$ and $x_B$=0.36. The $ed \to ed\pi^0$ cross sections are found compatible with the small values expected from theoretical models. The $en \to en\pi^0$ cross sections show a dominance from the response to transversely polarized photons, and are in good agreement with calculations based on the transversity GPDs of the nucle…
Removal of molecular contamination in low-energy RIBs by the isolation-dissociation-isolation method
2020
Nuclear instruments & methods in physics research / B 463, 324 - 326 (2020). doi:10.1016/j.nimb.2019.04.072
Towards 14C-free liquid scintillator
2017
A series of measurements has been started where the 14C concentration is determined from several liquid scintillator samples. A dedicated setup has been designed and constructed with the aim of measuring concentrations smaller than 10−18. Measurements take place in two underground laboratories: in the Baksan Neutrino Observatory, Russia, and in the new Callio Lab in the Pyhäsalmi mine, Finland. Low-energy neutrino detection with a liquid scintillator requires that the intrinsic 14C concentration in the liquid is extremely low. In the Borexino CTF detector the concentration of 2 × 10−18 has been achieved being the lowest value ever measured. In principle, the older the oil or gas source that…
Measuring the 14C content in liquid scintillators
2016
We are going to perform a series of measurements where the 14C/12C ratio will be measured from several liquid scintillator samples with a dedicated setup. The setup is designed with the aim of measuring ratios smaller than 10−18. Measurements take place in two underground laboratories: in the Baksan Neutrino Observatory, Russia and in the Pyh¨asalmi mine, Finland. In Baksan the measurements started in 2015 and in Pyh¨asalmi they start in the beginning of 2015. In order to fully understand the operation of the setup and its background contributions a development of simulation packages has also been started. Low-energy neutrino detection with a liquid scintillator requires that the intrinsic …
The ALHAMBRA survey: B -band luminosity function of quiescent and star-forming galaxies at 0.2 ≤ z < 1 by PDF analysis
2016
[Aims]: Our goal is to study the evolution of the B-band luminosity function (LF) since z ∼ 1 using ALHAMBRA data. [Methods]: We used the photometric redshift and the I-band selection magnitude probability distribution functions (PDFs) of those ALHAMBRA galaxies with I ≤ 24 mag to compute the posterior LF. We statistically studied quiescent and star-forming galaxies using the template information encoded in the PDFs. The LF covariance matrix in redshift - magnitude - galaxy type space was computed, including the cosmic variance. That was estimated from the intrinsic dispersion of the LF measurements in the 48 ALHAMBRA sub-fields. The uncertainty due to the photometric redshift prior is also…