Search results for "MAGNETIC FIELD"

The Influence of a Magnetic Field on the Formation of Corrosion Defects in Selected Metals and Steels, Analysed Using Positron Annihilation Method

2014

The method of positron lifetime measurement was used to analyse the in uence of a magnetic eld on the kinetics of corrosion defect formation in near-surface layers of iron, titanium as well as S20 and S0H18N9 steel grades. The listed metals, which belong to ferroand paramagnetic materials, have di erent sensitivity to corrosion. It was found that not only the presence of a magnetic eld, but also its direction in uence the dimensions and the concentration of defects formed during corrosion.

Effect of magnetic field on the corrosion of iron and St20 steel as studied by positron annihilation [Phys. Status Solidi B 247(7), 1822-1828 (2010)]

2011

We alert our readers that part of the contents of the article by R. Pietrzak and R. Szatanik, Phys. Status Solidi B 247, 1822 (2010) [DOI 10.1002/pssb.200945124] was already published in an earlier conference proceedings paper by the same authors which appeared in Nukleonika 55, 31 (2010).

Collective effects inνν¯synchrotron radiation from neutron stars

1999

We have considered the collective effects in $\ensuremath{\nu}\overline{\ensuremath{\nu}}$ synchrotron radiation from an ultrarelativistic degenerate electron gas in neutron stars with strong magnetic fields. For this problem we apply a calculation method which explicitly makes use of the fact that the radiating electron moves semiclassically, but takes into account the interaction among particles in a quantum way. First we apply this method to calculate $\ensuremath{\nu}\overline{\ensuremath{\nu}}$ synchrotron radiation by an ultrarelativistic electron in vacuum and we compare this result with that obtained previously by other techniques. When a degenerate plasma is considered, we show tha…

The Influence of Magnetic Field on Annihilation of Positrons in Corroded Steel St-20

2006

Langevin approach to collisional bremsstrahlung in a magnetic field

1994

A Pooled Analysis of Extremely Low-Frequency Magnetic Fields and Childhood Brain Tumors

2010

Pooled analyses may provide etiologic insight about associations between exposure and disease. In contrast to childhood leukemia, no pooled analyses of childhood brain tumors and exposure to extremely low-frequency magnetic fields (ELF-MFs) have been conducted. The authors carried out a pooled analysis based on primary data (1960–2001) from 10 studies of ELF-MF exposure and childhood brain tumors to assess whether the combined results, adjusted for potential confounding, indicated an association. The odds ratios for childhood brain tumors in ELF-MF exposure categories of 0.1–<0.2 μT, 0.2–<0.4 μT, and ≥0.4 μT were 0.95 (95% confidence interval: 0.65, 1.41), 0.70 (95% CI: 0.40, 1.22), and 1.1…

Highly tunable optically switched time delay line for transversal filtering

2003

A novel tunable dispersion device, based on two chirped fibre gratings subjected to non-uniform magnetic fields, is presented. A large degree of tunability is achieved from 250 to 750 ps/nm. This is used to demonstrate RF filtering in the 3-11 GHz range.

Planar metamaterial analogue of electromagnetically induced transparency for plasmonic sensing.

2009

We experimentally demonstrate a planar metamaterial analogue of electromagnetically induced transparency at optical frequencies. The structure consists of an optically bright dipole antenna and an optically dark quadrupole antenna, which are cut-out structures in a thin gold film. A pronounced coupling-induced reflectance peak is observed within a broad resonance spectrum. A metamaterial sensor based on these coupling effects is experimentally demonstrated and yields a sensitivity of 588 nm/RIU and a figure of merit of 3.8.

Search for the Rare Leptonic Decay B+→μ+νμ

2004

A search for the rare leptonic decay with data collected at the resonance by the BABAR experiment was carried out. The decay rate was sensitive to the product of the Cabibbo Kobayashi Maskawa matrix element (Vub and the B decay constant fb, which was propotional to the wave function for zero separation between the quarks. The data used in the analysis was collectd with BABAR detector at the PEP-II storage ring and the sample consisted of an integrity luminosity of 81.4 fb-1. The systematic uncertainty in the signal efficiency was evaluated which included the muon candidate selection and the reconstruction efficiency of the companion B.

Spin up and phase fluctuations in the timing of the accreting millisecond pulsar XTE J1807-294

2007

We performed a timing analysis of the 2003 outburst of the accreting X-ray millisecond pulsar XTE J1807-294 observed by RXTE. Using recently refined orbital parameters we report for the first time a precise estimate of the spin frequency and of the spin frequency derivative. The phase delays of the pulse profile show a strong erratic behavior superposed to what appears as a global spin-up trend. The erratic behavior of the pulse phases is strongly related to rapid variations of the light curve, making it very difficult to fit these phase delays with a simple law. As in previous cases, we have therefore analyzed separately the phase delays of the first harmonic and of the second harmonic of …