Search results for "dipole"
showing 10 items of 982 documents
Simple modeling of dipolar coupled 7Li spins and stimulated-echo spectroscopy of single-crystalline β-eucryptite
2004
Abstract Stimulated-echo spectroscopy has recently been applied to study the ultra-slow dynamics of nuclear spin-3/2 probes such as 7 Li and 9 Be in solids. Apart from the dominant first-order quadrupolar interaction in the present article also the impact of the homonuclear dipolar interactions is considered in a simple way: the time evolution of a dipole coupled pair of spins with I =3/2 is calculated in an approximation, which takes into account that the satellite transitions usually do not overlap. Explicit analytical expressions describing various aspects of a coupled quadrupolar pair subjected to a Jeener–Broekaert pulse sequence are derived. Extensions to larger spin systems are also …
W polarisation beyond helicity fractions in top quark decays
2010
30 páginas, 14 figuras, 1 tabla.-- arXiv:1005.5382v2
Evaluation of the magnetic moments of radium isotopes
1990
Using the relativistic linked cluster many-body perturbation procedure we have obtained the hyperfine field at the nucleus of the Ra+ ion in the2S1/2 ground state. There is good agreement between the calculated magnetic moment of213Ra and the results of a recent Zeeman measurement by the collinear laser beam technique. Detailed comparison is carried out between our result and earlier ones.
Measurement of the b hadron lifetime with the dipole method
1993
A measurement of the average lifetime of b hadrons has been performed with the dipole method on a sample of 260000 hadronic Z decays recorded with the ALEPH detector during 1991. The dipole is the distance between the vertices built in the opposite hemispheres. The mean dipole is extracted from all the events without attempting b enrichment. Comparing the average of the data dipole distribution with a Monte Carlo calibration curve obtained with different b lifetimes, an average b hadron lifetime of 1.51 +/- 0.08 ps is extracted. RI ANTONELLI, ANTONELLA/C-6238-2011; Buttar, Craig/D-3706-2011; Stahl, Achim/E-8846-2011; Passalacqua, Luca/F-5127-2011; Murtas, Fabrizio/B-5729-2012; St.Denis, Ric…
Data Blinding for the nEDM Experiment at PSI
2020
Psychological bias towards, or away from, prior measurements or theory predictions is an intrinsic threat to any data analysis. While various methods can be used to try to avoid such a bias, e.g. actively avoiding looking at the result, only data blinding is a traceable and trustworthy method that can circumvent the bias and convince a public audience that there is not even an accidental psychological bias. Data blinding is nowadays a standard practice in particle physics, but it is particularly difficult for experiments searching for the neutron electric dipole moment (nEDM), as several cross measurements, in particular of the magnetic field, create a self-consistent network into which it …
Evolution of nuclear structure in neutron-rich odd-Zn isotopes and isomers
2017
Collinear laser spectroscopy was performed on Zn (Z=30) isotopes at ISOLDE, CERN. The study of hyperfine spectra of nuclei across the Zn isotopic chain, N=33–49, allowed the measurement of nuclear spins for the ground and isomeric states in odd-A neutron-rich nuclei up to N=50. Exactly one long-lived (&
The new vacuum-mode recoil separator MARA at JYFL
2008
Abstract A new vacuum-mode recoil separator MARA (Mass Analysing Recoil Apparatus) is under design and construction at the Department of Physics in the University of Jyvaskyla. The separator is intended to separate reaction products from the primary beam in mass region below A = 150 . The ion-optical configuration of the separator will be QQQDEDM, where a magnetic quadrupole (Q) triplet is followed by an electrostatic deflector (DE) and a magnetic dipole (DM). The total length of MARA will be less than 7.0 m and the first order resolving power more than 250 for a beam spot size of 2 mm. In this contribution the main properties of MARA are given and results from simulations are shown.
Investigation of the Dipole Response in Exotic Nuclei – Experiments at the LAND-R$^3$B Setup
2012
We present experimental results on the electromagnetic excitation of neutron-rich nickel isotopes, making use of the (RB)-B-3-LAND setup at GSI. Exotic beams were produced at approximately 500 MeV/u and their reactions were studied in inverse kinematics. Integral cross sections for Ni-58 are discussed and compared to previous data, providing a validation of our experimental method. The El excitation-energy distribution of the unstable Ni-68 is presented as well, showing an excess in cross section in the 1n decay channel when compared only with a typical Giant Dipole Resonance.
Dipole amplitude with uncertainty estimate from HERA data and applications in Color Glass Condensate phenomenology
2014
We determine the initial condition for the small-x evolution equation (BK) from the HERA deep inelastic scattering data using a new parametrization that also keeps the unintegrated gluon distribution positive. The obtained dipole amplitude and its uncertainty estimate can be used to compute single inclusive particle production in proton-proton and proton-nucleus collisions. We argue that one has to use consistently the proton transverse area measured in DIS and the total inelastic cross section when calculating the single inclusive cross section. This leads to a midrapidity nuclear modification factor RpA that approaches unity at large transverse momentum, independently of the center-of-mas…
The energy loss system of the electron scattering facility at the Mainz 300 MeV linear accelerator
1978
Abstract An energy loss system was constructed for the electron scattering facility at the Mainz 300 MeV linear accelerator with the aim of improving the energy resolution and increasing the useful beam current. The main features of the design are: (1) the existing system (conventional mode) is kept in full operation, (2) for the energy loss mode, the electron beam is deflected vertically downwards and then returned to the original beam line by the dispersion matching system, consisting of three dipole magnets and one quadrupole magnet, (3) the dispersion of the beam on the target can be tuned to the dispersion of the spectrometer with the aid of the quadrupole magnet. With the installation…