We report on the results of optical follow-up observations of the counterpart of GRB 970508, starting 7 hours after the event. Multi-color U, B, V, R c and I c band observations were obtained during the first three consecutive nights. The counterpart was monitored regularly in R c until ∼ 4 months after the burst. The light curve after the maximum follows a decline that can be fitted with a pow...

Laser-induced-plasma-assisted ablation (LIPAA) is a promising micro-machining method that can fabricate microstructure on hard and transparent double-polished single crystal sapphire (SCS). While ablating, a nanosecond pulse 1064 nm wavelength laser beam travels through the SCS substrate and bombards the copper target lined up behind the substrate, which excites the ablating plasma. When laser ...

We report observations of the early light curves of GRB060418 and GRB060607A, carried out with the pink robotic telescope REM. A clear peak is detected for both events, which is interpreted as the onset of the afterglow, that is the time at which the fireball starts decelerating. This detection allows to directly measure the initial fireball Lorentz factor, which was found to be Γ0 ≈ 400 for bo...

The present common view about GRB origin is related to cosmology, what is based on statistical analysis, and on measurements of the redshifts in the GRB optical afterglows of long GRB. No correlation is found between redshifts, GRB spectrum, and total GRB fluence. Comparison of KONUS and BATSE data about statistics and hard X-ray lines is done, and some differences are noted. Hard gamma-ray aft...

background: as bremsstrahlung photon beam fluence is important parameter to be known in a photonuclear reaction experiment as the number of produced particle is strongly depends on photon fluence. materials and methods: photon production yield from different thickness of aluminum target has been estimated using artificial neural network (ann) model. target thickness and incoming electron energy...

Ultra High Energy (UHE) neutrino Astronomy and relic Neutrino masses may play a key role in solving the Ultra High Energy Cosmic Ray (UHECR) puzzle within the Z-Showering model. Tau air-shower originated by UHE neutrino in matter may probe and amplify this expected UHE neutrino Astronomy. The discover of upcoming and horizontal τ air-showers (UPTAUs, HORTAUs), born by UHE, ντ interacting inside...

Ultra High Energy (UHE) neutrino Astronomy and relic Neutrino masses may play a key role in solving the Ultra High Energy Cosmic Ray (UHECR) puzzle within the Z-Showering model. Tau air-shower originated by UHE neutrino in matter may probe and amplify this expected UHE neutrino Astronomy. The discover of upcoming and horizontal τ air-showers (UPTAUs, HORTAUs), born by UHE, ντ interacting inside...

The relationship between the amount of light and the amount of response for any photobiological process can be based on the number of incident quanta per unit time (fluence rate-response) or on the number of incident quanta during a given period of irradiation (fluence-response). Fluence-response and fluence rate-response relationships have been measured for second positive phototropism by s...

The question of the appropriate extrapolation to low dose has long been a subject of controversy. A linear no-threshold model is favored by regulatory bodies as the basis of RBE assignments and estimates of radiation hazards to the general population. This model is largely supported by extensive application of the linear-quadratic survival formula "fitted" statistically to a wide variety of exp...

We have examined phytochrome regulated changes in transcript abundance for 11 different light regulated mRNAs in developing pea buds. Fluence-response curves were measured for changes in transcript abundance in response to red light pulses in both the low and very low fluence ranges. Most transcripts show only low fluence responses, with a threshold of approximately 10 micromoles per square met...