Lens effect

Figure 3.4 Prism and lens effect of an electric sector field with radius re and sector angle . The ions coming from the ion-emitting point A enter the electric sector field after a distance of le and are focused on the imaging curve behind the electric sector field at a distance of e". Ions of energy e(V + AV) and e(V — AV) are focused in two separate images A " and A2". (Massenspektrometrie Herausgegeben, Von Kienitz, H., Verlag Chemie, GmbH, Weinheim (1968). Reproduced by permission of Wiley-VCH)...

Magnetic sector field equilibr Lorentz force and centrifugal force mv2 n-e-v-B= 2 - direction focusing (lens effect) - separation after m/z (prism effect) 1 500 5 000 TIMS, organic ms, double-focusing sector field ms, tandem ms... 

Gravitational lens effects offer a precious mean for probing the matter distribution in the Universe. From the search of matter in the Galactic halo to the study of the large-scale structure of the Universe, gravitational lens surveys represent a unique alternative to galaxy catalogues and have been widely used till now. 

In practice, the total deflection angle is at most about an arcmin. This is the case for the most massive galaxy clusters. It implies that in the subsequent calculations it is possible to ignore the bending of the trajectories and calculate the lens effects as if the trajectories were straight lines. This is the Bom... 

Eventually, one can do another approximation by noting that in general the deflection takes place along a very small fraction of the trajectory between the sources and the observer. One can then assume that the lens effect is instantaneous and is produced through the crossing of a plane, the lens plane. This is... 

The study of galaxy clusters has become a very active field since the discovery of the first gravitational arc in Abell cluster A370 Soucail et al. (1998). Galaxy clusters give the most dramatic example of gravitational lens effects in a cosmological context. The difficulty is however to describe the shape of their mass distribution. 

In this section the possibility of using lens effects to probe the large-scale structure of the Universe is considered. The difficulty lies in that the distortion induced by the lenses can be very small. The projected potential should then be reconstructed with a statistical analysis on the deformation effects measured on a lot of background objects. For slightly extended objects such as background galaxies the deformation is described by the amplification matrix, the components of component of which are usually written... 

The amplification matrix is given by the superposition of lens effects of the different mass layers. Generalizing this result to a continuous held 4, the component of the amplification matrix can then be inferred from the line of sight integration of the gravitational potential angular derivatives,... 

The achievable pulse length is determined by the total number of modes that can contribute to the pulse. The broader the frequency comb the shorter the possible pulse length, ideally reaching the so-called Fourier limit. In fact, the spectral width is usually limited by the width over which the GVD and higher order terms can be compensated for by mode pulling [5,6]. Cavity modes that are outside this bandwidth are suppressed without the help of the Kerr-lens effect and do not oscillate. 

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