Search results for "Acceleration"

Chromatic and Spherical Aberration Correction Using Time-Dependent Acceleration and Lens Fields

2003

Positioning in a flat two-dimensional space-time

2008

The basic theory on relativistic positioning systems in a two-dimensional space-time and the analysis of the possibility of making relativistic gravimetry with these systems have been presented elsewhere [Phys. Rev. D 73 , 084017 (2006); Phys. Rev. D 74 , 104003 (2006)]. Here we summarize these results and we outline new issues on the relativistic positioning systems in Minkowski plane. We point out that the accelerations of the emitters and of the user along their trajectories are determined by the sole knowledge of the emitter positioning data and of the acceleration of only one of the emitters and only during a light echo interval.

Precision measurement of the structure function ratiosF 2 He /F 2 D ,F 2 C /F 2 D andF 2 Ca /F 2 D

1991

We present the structure function ratiosF2He/F2D,F2C/F2D andF2Ca/F2D measured in deep inelastic muon-nucleus scattering at an incident muon momentum of 200 GeV. The kinematic range 0.0035<x<0.65 and 0.5<Q2<90 GeV2 is covered. At lowx the three ratios are significantly smaller than unity and the size of the depletion grows with decreasingx and increasing mass numberA. At intermediatex the ratios show an enhancement of about 2% above unity for C/D and Ca/D, possibly less for He/D. There are indications of someQ2 dependence in the Ca/D data. The integrals of the structure function differencesF2A−F2D are discussed.

Angular distributions in quasi-fission reactions

1986

Abstract Angular distributions for fission-like fragments were measured in the systems 50Ti, 56Fe + 208Pb by applying an off-line K X-ray activation technique. The distributions d2σ/dθdZ exhibit forward-backward asymmetries that are strongly Z-dependent. They result from a process (quasi-fission) which yields nearly symmetric masses in times comparable to the rotational period of the composite system. A method for obtaining the variance of the tilting angular momentum, K02, from these skewed, differential angular distributions is described. The results indicate that the tilting mode is not fully excited in quasi-fission reactions. The results are compared to the sum of the variances of all …

Gravitational waves from first order phase transitions as a probe of an early matter domination era and its inverse problem

2016

We investigate the gravitational wave background from a first order phase transition in a matter-dominated universe, and show that it has a unique feature from which important information about the properties of the phase transition and thermal history of the universe can be easily extracted. Also, we discuss the inverse problem of such a gravitational wave background in view of the degeneracy among macroscopic parameters governing the signal.

The 1.5GeV harmonic double-sided microtron at Mainz University

2008

Abstract At the Institut fur Kernphysik of Mainz University a harmonic double-sided microtron (HDSM) has been built to extend the experimental capabilities for nuclear and particle physics experiments to higher excitation energies. This novel microtron variant accelerates the 0.855 GeV continuous wave (cw) electron beam of the established three-staged race track microtron (RTM) cascade MAMI B up to 1.5 GeV. It consists of two normal conducting linear accelerators (linacs) through which the electrons are guided up to 43 times by a pair of 90°-bending magnets at each end. For beam dynamical reasons the linacs operate at the harmonic frequencies of 4.90 and 2.45 GHz. The extended facility is c…

Calibration of the ISOLDE acceleration voltage using a high-precision voltage divider and applying collinear fast beam laser spectroscopy

2011

A high-voltage divider with accuracy at the ppm level and collinear laser spectroscopy were used to calibrate the highvoltage installation at the radioactive ion beam facility ISOLDE at CERN. The accurate knowledge of this voltage is particularly important for collinear laser spectroscopy measurements. Beam velocity measurements using frequencycomb based collinear laser spectroscopy agree with the new calibration. Applying this, one obtains consistent results for isotope shifts of stable magnesium isotopes measured using collinear spectroscopy and laser spectroscopy on laser-cooled ions in a trap. The long-term stability and the transient behavior during recovery from a voltage dropout were…

Beamline pulsing system for cyclotrons

1998

Abstract A beamline pulsing system for cyclotrons is presented. The function of this system is to modify the structure of a cyclotron ion beam guided to the desired research target by a beamline. In some in-beam experiments, an adjustment of the time structure of the beam is sometimes needed. This kind of situation occurs if, for example, the life time of the target material is longer than the period corresponding to the beam frequency. In this case, the frequency of the ion pulses hitting the target is 10–21 MHz depending on the frequency of the acceleration voltage. The adjustment of the ion beam pulse frequency is carried out by a beamline deflector. Deflection is achieved by feeding a h…

Optimal β-beam at the CERN-SPS

2006

In this talk, based on the work [J. Burguet-Castell et al., Nucl. Phys. B 725 (2005) 306], we present an analysis of the sensitivity to the mixing angle θ 13 and the CP-violating phase δ that could be achieved by a β-beam experiment based at the SPS accelerator at CERN. We estimate the optimal γ boost of the 6He and 18Ne ions for the proposed baseline CERN-Frejus (130 km), and also perform a simultaneous optimization of the ion boost and the baseline. A possible improvement of the current SPS accelerator is considered as well. After comparing the sensitivities of all relevant setups, we conclude that a β-beam running at the maximum acceleration achievable by the SPS, γ = 150 / 250 , and wit…

The Collinear Fast Beam laser Spectroscopy (Cfbs) experiment at Triumf

2016

Abstract Laser spectroscopy experiments at radioactive ion beam facilities around the world investigate properties of exotic nuclei for scientific endeavours such as, but not limited to, the investigation of nuclear structure. Advancements in experimental sensitivity and performance are continuously needed in order to extend the reach of nuclei that can be measured. The collinear fast beam laser spectroscopy ( Cfbs ) setup at Triumf , coupled to an out-of-plane radio-frequency quadrupole Paul trap, enables measurements of some of the most fundamental nuclear properties for long-lived ground and isomeric states. The first comprehensive overview of the Cfbs experiment is provided along with d…