Quantitative predictions for the energy and A dependence of the nuclear photoabsorption cross section and inelastic electron-nucleus scattering are given. In general each nucleon does not contribute equally to the total photon-nucleus cross section when coherent contributions of photoproduced hadrons are taken into account. At low energies (E Y N 1 BeV) the cross sections are proportional to nu...

We report what is to our knowledge a record high value for an intrinsic two-photon absorption (TPA) cross section, sigma(2) = 11 x 10(-47)> cm>(4)> s photon(-1) molecule(-1), measured with femtosecond pulses in a new dendrimer molecule comprising 29 repeat units of 4, 4(?)-bis(diphenylamino)stilbene chromophore. We measure the dependence of TPA on excitation wavelength in three consecutive gene...

One of the most successful models of ionization is the photo-absorption ionization model . The model assumes that the process of interest is dominated by single-photon exchange which allows one to relate the ionization process to the photo-absorption process for which the data is more readily available. Also the model is restricted to non-relativistic recoil electron, thus it does not include h...

Two-photon spectroscopy of fluorescent proteins is a powerful bio-imaging tool characterized by deep tissue penetration and little damage. However, two-photon spectroscopy has lower sensitivity than one-photon microscopy alternatives and hence a protein with a large two-photon absorption cross-section is needed. We use time-dependent density functional theory (TD-DFT) at the B3LYP/6-31+G(d,p) l...

We study multiple exciton generation (MEG) in electronically coupled films of PbSe quantum dots (QDs) employing ultrafast time-resolved transient absorption spectroscopy. We demonstrate that the MEG efficiency in PbSe does not decrease when the QDs are treated with hydrazine, which has been shown to greatly enhance carrier transport in PbSe QD films by decreasing the interdot distance. The quan...

We calculate the electromagnetic absorption cross section of long and narrow nanowires, in the so-called quasi-1D limit. We consider only two transverse bands and compute the dipole absorption cross section taking into account quasiparticle transitions from negative to positive energy eigenstates of the Bogoliubov-de Gennes Hamiltonian. The presence of the zero energy (Majorana) state manifests...

Measurements from a nine-wavelength light absorption and attenuation instrument mounted on a towed, undulating vehicle (SeaSoar) capable of rapidly pro"ling the water column } complete up-down cycles in 1.5}12 min depending on the maximum sampling depth } are used to characterize strong spatial variations in the distributions of upper-ocean biooptical properties. Water sampled from adjacent to ...