We study single-shot damage morphology of MgF2 irradiated under 800 nm laser using scanning electronic microscope (SEM). The dependence of damage threshold on laser pulse width is measured by the linear relationship between the area of damage spot and the logarithm of laser energy. The pulse duration ranges from 55 fs to 750 fs. We develop the multiple-equation model (Phys. Rev. Lett. Vol.92, p...

Next generation free electron lasers aim to generate x-ray pulses with pulse durations down to 30 fs, and possibly even sub-fs. Synchronization of various stages of the accelerator and the probe laser system to the x-ray pulses with stability on the order of the pulse width is necessary to make maximal use of this capability. We are developing an optical timing synchronization system in order t...

In this paper, the studies of finding the failure location on a sample cable by using the multiple pulse reflection method and the fault on the results of the measurement have been examined. A pulse generator with amplitude of 12 V and pulse width from 20 ns to 2 us has been designed as a multiple pulse reflection meter. The velocity of reflection pulse is calibrated in embedded system. The SOP...

We analyze the time profiles of individual gamma-ray burst (GRB) pulses, that are longer than 2 s, by modelling them with analytical functions that are based on physical first principles and well-established empirical descriptions of GRB spectral evolution. These analytical profiles are independent of the emission mechanism and can be used to model both the rise and decay profiles allowing for ...

Image is often degraded by more than one type of noise. In order to design an efficient filter to remove mixed noise from image, this paper proposes a weighted-linking pulse coupled neural network (PCNN) model so as to construct a two-channel parallel noise filter using four PCNNs of this model. This filter detects noise using the pulses generated by neurons, and iteratively removes noise by th...

The pulse width of hard undulator radiation (32 ps width, energy 14 keV) was determined by intensity interferometry. The method, in combination with various x-ray monochromators, enables measurements to be taken over a wide range of time frames, from ns to fs. The applicable target includes measurements of ultrafast x-ray pulse widths from fourth generation synchrotron light sources.

Pulse compression technique combines the high energy characteristic of a longer pulse width with the high resolution characteristic of a narrower pulse width. The major aspects that are considered for a pulse compression technique are signal to sidelobe ratio (SSR), noise and Doppler shift performances. The traditional algorithms like autocorrelation function (ACF), recursive least square (RLS)...

The multilevel inverter topology gives the advantages of usage in high power and high voltage application with reduced harmonic distortion without a transformer. This paper presents a comparative study of nine level diode clamped inverter for constant Switching frequency of sinusoidal Pulse width Modulation and sinusoidal Natural Pulse width Modulation with switching frequency Optimal Modulation.

Long pulses overlap Echoes Pulse width Pulse-on mean power B ea m sc an pa tt er n