Near-infrared radiation around 1000 nm generated from the interaction of a high-density MeV electron beam, obtained by impinging an intense ultrashort laser pulse on a solid target, with a metal grating is observed experimentally. Theoretical modeling and particle-in-cell simulation suggest that the radiation is caused by the Smith-Purcell mechanism. The results here indicate that tunable terah...

We present measurements of the polarization dependencies x-ray signal photons generated by effect parametric down-conversion x rays into ultraviolet radiation. The results exhibit pronounced discrepancies with classical model for nonlinearity but qualitatively agree a recently developed quantum mechanical theory nonlinear interaction. Our work shows that reconstruction atomic scale charge distr...

Free-electron lasers are radiation sources, based on the coherent emission of synchrotron radiation of relativistic electrons within an undulator or wiggler. The resonant radiation wavelength depends on the electron beam energy and can be tuned over the entire spectrum from micrometer to X-ray radiation. The emission level of free-electron lasers is several orders of magnitude larger than the e...

Radiation-reaction effects in the interaction of an electron bunch with a superstrong focused ultrashort laser pulse are investigated in the quantum radiation-dominated regime. The angle-resolved Compton scattering spectra are calculated in laser pulses of variable duration using a semiclassical description for the radiation-dominated dynamics and a full quantum treatment for the emitted radiat...

Inhibitors of the molecular chaperone Hsp90 have been shown to enhance tumor cell radiosensitivity. To begin to address the mechanism responsible, we have determined the effect of the Hsp90 inhibitor 17-(dimethylaminoethylamino)-17-demethoxygeldanamycin (17DMAG) on the DNA damage response to radiation. Exposure of MiaPaCa tumor cells to 17DMAG, which results in radiosensitization, inhibited the...

the currently reactor wreckage in fukushima raised the following important questions: is our knowledge of the possible dangers of ionizing radiation sufficient to warrant special action? what is the role of the medical community in technical radiation accidents from windscale to fukushima? what is the role of the medical community in terrorist radiation attacks? are we prepared for those challe...

this study assessed the optimum water need of pepper (capsicum annuum l. cv. california wonder) and the critical irrigation level to be applied in order to achieve a reasonable economic yield in water shortage conditions. in a controlled field experiment involving five different treatments, seasonal evapotranspiration for pepper fluctuated from 89 mm in the severe stress treatment (i0.00) to 1,...