The anisotropy and polarization of the cosmic microwave background radiation (CMBR) induced by the scalar and tensor metric perturbations are computed in the long-wavelength limit. It is found that the large-scale polarization of CMBR induced by the decaying tensor mode can reach a few percents. This is different from the scalar or inflation-induced tensor mode, whereas the polarization is at l...

We study resonant two-color two-photon ionization of helium via the 1s3p (1)P(1) state. The first color is the 15th harmonic of a tunable Ti:sapphire laser, while the second color is the fundamental laser radiation. Our method uses phase-locked high-order harmonics to determine the phase of the two-photon process by interferometry. The measurement of the two-photon ionization phase variation as...

The ionization dynamics of pure He nanodroplets irradiated by Extreme ultraviolet radiation is studied using Velocity-Map Imaging PhotoElectron-PhotoIon COincidence spectroscopy. We present photoelectron energy spectra and angular distributions measured in coincidence with the most abundant ions He(+), He2(+), and He3(+). Surprisingly, below the autoionization threshold of He droplets, we find ...

The charge loss due to initial recombination was measured for various therapy level ionization chamber types. Different methods were applied. Measurements were performed in Co beams, pulsed high-energy photon beams and pulsed high-energy electron beams. The results are mutually consistent within less than 0.05 %. Within this uncertainty initial recombination and diffusion do not depend on the r...

By combining multiple electron coincidence detection with ionization by synchrotron radiation, we have obtained resolved spectra of the OCS(3+) ion created through the double Auger effect. The form of the spectra depends critically on the identity of the atom bearing the initial hole. High and intermediate level electron structure calculations lead to an assignment of the resolved spectrum from...

The IAEA Code of Practice for Absorbed Dose Determination in Photon and Electron Beams TRS 277 gives recommendations for the absorbed dose determination in high energy photon and electron beams based on the use of ionization chambers calibrated in terms of air kerma. It was the task of the present work to test the validity of the Code for *°Co gamma radiation for ton different types of ionizati...

One-photon mass-analyzed threshold ionization (MATI) spectrum of trans-C(2)H(2)Cl(2) was obtained by using vacuum ultraviolet radiation generated by four-wave mixing in Kr. The ionization energy determined from the position of the 0-0 band in the spectrum was 9.6306 +/- 0.0006 eV. Ten vibrational fundamentals for the cation were identified. The spectrum also displayed abundant overtones and com...

In anticipation of upcoming two-photon double ionization of atoms and particularly Helium, under strong short wavelength radiation sources (45 eV), we present quantitative signatures of direct twophoton double ejection, in the photoelectron spectrum (PES) and the peak power dependence, that can be employed in the interpretation of related data. We show that the PES provides the cleanest signatu...