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11.
We emphasize that it is extremely important for future neutrinoless double-beta(0νββ)decay experiments to reach the sensitivity to the effective neutrino mass|mββ|≈1 meV.With such a sensitivity,it is highly possible to discover the signals of 0νββ decays.If no signal is observed at this sensitivity level,then either neutrinos are Dirac particles or stringent constraints can be placed on their Majorana masses.In this paper,assuming the sensitivity of|mββ|≈1 meV for future 0νββ decay experiments and the precisions on neutrion oscillation parameters after the JUNO experiment,we fully explore the constrained regions of the lightest neutrino mass m1 and two Majorana-type CP-violating phases{ρ,σ}.Several important conclusions in the case of normal neutrino mass ordering can be made.First,the lightest neutrino mass is severely constrained to a narrow range m1∈[0.7,8]meV,which together with the precision measurements of neutrino mass-squared differences from oscillation experiments completely determines the neutrino mass spectrum m2∈[8.6,11.7]meV ing phases is limited to ρ∈[130°,230°],which cannot be obtained from any other realistic experiments.Third,the sum of three neutrino masses is found to beΣ≡m1+m2+m3∈[59.2,72.6]meV,while the effective neutrino mass for beta decays turns out to be mβ≡(|Ue1|2m1^2+|Ue2|2m2^2+|Ue3|2m3^2)1/2∈[8.9,12.6]meV.These observations clearly set up the roadmap for future non-oscillation neutrino experiments aiming to solve the fundamental problems in neutrino physics. 相似文献
12.
建立了采用实时直接分析-串联质谱(DART-MS/MS)对火锅底料、牛肉面汤及调味料中5种非法添加的罂粟壳生物碱进行快速筛查的方法。样品经乙腈提取净化后,在离子化温度为300℃、栅极电压为150 V、进样速率为0.8 m m/s的DART离子源正离子模式条件下进样,以电喷雾离子源正离子多反应监测(MRM)模式进行检测,实现了样品经简单预处理后使用DART-MS/MS进行检测的新方法。该方法简便、快速,能满足大批量非法添加样品的快速筛查分析要求。 相似文献
13.
Oleksandr Kramar Yuriy Skorenkyy Leonid Didukh Yuriy Dovhopyaty 《Molecular Crystals and Liquid Crystals》2018,671(1):55-66
AbstractPhenomenon of ferromagnetic ordering was for a long time associated exclusively with transition metal and rare-earth compounds. Nowadays this view is challenged by growing evidence that in molecular carbon-based systems the ferromagnetic alignment of spins can be observed as well. We have developed a microscopical model of a fulleride electronic subsystem taking into account triple orbital degeneracy of energy states within the configurational-operator approach. Using the Green function method the energy spectrum of the model has been calculated. Conditions for the ferromagnetic state stabilization have been determined. Static electrical conductivity and effective masses of current carriers in the system with orbitally degenerated energy band have been obtained. In the ground state and for low temperatures at different forms of unperturbed density of electronic states the concentration dependences of transport characteristics for less-then-half-filled lower quasiparticle subband have been calculated. 相似文献
14.
An atomic-level controlled etching(ACE)technology is invstigated for the fabrication of recessed gate AlGaN/GaN high-electron-mobility transistors(HEMTs)with high power added efficiency.We compare the recessed gate HEMTs with conventional etching(CE)based chlorine,Cl2-only ACE and BCl3/Cl2ACE,respectively.The mixed radicals of BCl3/Cl2were used as the active reactants in the step of chemical modification.For ensuring precise and controllable etching depth and low etching damage,the kinetic energy of argon ions was accurately controlled.These argon ions were used precisely to remove the chemical modified surface atomic layer.Compared to the HEMTs with CE,the characteristics of devices fabricated by ACE are significantly improved,which benefits from significant reduction of etching damage.For BCl3/Cl2ACE recessed HEMTs,the load pull test at 17 GHz shows a high power added efficiency(PAE)of 59.8%with an output power density of 1.6 W/mm at Vd=10 V,and a peak PAE of 44.8%with an output power density of 3.2 W/mm at Vd=20 V in a continuous-wave mode. 相似文献
15.
S. Gandolfi F. Pederiva S. a Beccara 《The European Physical Journal A - Hadrons and Nuclei》2008,35(2):207-211
We computed ground-state energies of calcium isotopes from 42Ca to 48Ca by means of the Auxiliary Field Diffusion Monte Carlo (AFDMC) method. Calculations were performed by replacing the 40Ca core with a mean-field self-consistent potential computed using the Skyrme interaction. The energy of the external neutrons
is calculated by projecting the ground state from a wave function built with the single-particle orbitals computed in the
self-consistent external potential. The shells considered were the 1F
7/2 and the 1F
5/2 . The Hamiltonian employed is semi-realistic and includes tensor, spin-orbit and three-body forces. While absolute binding
energies are too deep if compared with experimental data, the differences between the energies for nearly all isotopes are
in very good agreement with the experimental data. 相似文献
16.
M. Mukherjee D. Beck K. Blaum G. Bollen J. Dilling S. George F. Herfurth A. Herlert A. Kellerbauer H. -J. Kluge S. Schwarz L. Schweikhard C. Yazidjian 《The European Physical Journal A - Hadrons and Nuclei》2008,35(1):1-29
ISOLTRAP is a Penning trap mass spectrometer for high-precision mass measurements on short-lived nuclides installed at the
on-line isotope separator ISOLDE at CERN. The masses of close to 300 radionuclides have been determined up to now. The applicability
of Penning trap mass spectrometry to mass measurements of exotic nuclei has been extended considerably at ISOLTRAP by improving
and developing this double Penning trap mass spectrometer over the past two decades. The accurate determination of nuclear
binding energies far from stability includes nuclei that are produced at rates less than 100 ions/s and with half-lives well
below 100ms. The mass-resolving power reaches 107 corresponding to 10keV for medium heavy nuclei and the uncertainty of the resulting mass values has been pushed down to below
10-8. The article describes technical developments achieved since 1996 and the present performance of ISOLTRAP. 相似文献
17.
C. Scheidenberger 《The European Physical Journal A - Hadrons and Nuclei》2002,15(1-2):7-11
The present status and recent results from direct mass measurements of exotic nuclei are presented. ISOL, in-flight, and combined
facilities provide a wide variety of nuclides far-off stability covering a wide range of half-lives down to the sub-millisecond
region. Modern direct mass measurements are carried out using frequency and time-of-flight techniques. The obtained accurate
mass data point to nuclear-structure phenomena and serve as a basis for astrophysical and weak-interaction studies.
Received: 21 March 2002 / Accepted: 16 May 2002 / Published online: 31 October 2002
RID="a"
ID="a"e-mail: c.scheidenberger@gsi.de 相似文献
18.
K. Blaum G. Bollen F. Herfurth A. Kellerbauer H.-J. Kluge M. Kuckein E. Sauvan C. Scheidenberger L. Schweikhard 《The European Physical Journal A - Hadrons and Nuclei》2002,15(1-2):245-248
The cyclotron frequencies of singly charged carbon clusters Cn
+ (n ≥ 2) were measured with the Penning-trap mass spectrometer ISOLTRAP at ISOLDE/CERN. The present limit of mass accuracy δm/m = 1.2 . 10-8 and the extent of the mass-dependent systematic shift (δm/m)sys = 1.7(0.6) . 10-10/u
. (m - m
ref) of the setup were investigated for the first time. In addition, absolute mass measurements by use of pure clusters of the
most abundant carbon isotope 12C are now possible at ISOLTRAP.
Received: 21 March 2002 / Accepted: 16 May 2002 / Published online: 31 October 2002
RID="a"
ID="a"Present address: CERN, CH-1211 Geneva 23, Switzerland; e-mail: klaus.blaum@cern.ch 相似文献
19.
L. Vlahos S. Trakadas A. Gouliamos G. Plataniotis C. Papavasiliou 《Magnetic resonance imaging》1993,11(8):1227-1229
A case of extramedullary hemopoiesis in an 18-yr-old girl suffering from beta-thalassemia is reported. Extramedullary hemopoietic masses were localized apart from the paraspinal region in the retrocrural areas as well as the presacral region associated with massive destruction of the sacrum. The importance of recognition of hemopoietic masses in these regions in conditions other than hereditary hemolytic anaemias is briefly discussed. 相似文献
20.
Fritzsch like mass matrices with non-zero 22-elements both in U sector and D sector have been investigated in the context
of latest data regardingm
t
phys
, |V
ub|, |V
cb|, |V
td| and |V
ts|. Unlike several other phenomenological models, the present model not only accommodates the value ofm
t
phys
in the range 150–240 GeV, encompassing the CDF and D0 values, but is also able to reproduce |V
cb| ≊0.040 and |V
ub/Vcb| = 0.08±0.02 and |V
td| is predicted to lie in the range 0.005–0.014. Further, the angles of the unitarity triangle, related to the CP-violating
asymmetries, are calculated to be in the ranges −1.0⩽sin2α⩽−0.1, 0.6 ⩽sin2α⩽1.0 and 0.48⩽sin2β⩽0.56, which are in agreement
with other recent calculations. 相似文献