Multiplicity distribution and spectra of negatively charged hadrons in Au+Au collisions at sqrt(s_nn) = 130 GeV

The minimum bias multiplicity distribution and the transverse momentum and pseudorapidity distributions for central collisions have been measured for negative hadrons (h-) in Au+Au interactions at sqrt(s_nn) = 130 GeV. The multiplicity density at midrapidity for the 5% most central interactions is dNh-/deta|_{eta = 0} = 280 +- 1(stat)+- 20(syst), an increase per participant of 38% relative to ppbar collisions at the same energy. The mean transverse momentum is 0.508 +- 0.012 GeV/c and is larger than in central Pb+Pb collisions at lower energies. The scaling of the h- yield per participant is a strong function of pt. The pseudorapidity distribution is almost constant within |eta|<1.Comment: 6 pages, 3 figure

Light controls self-assembly of gallium nanoparticles

Light dramatically influences and regulates the self-assembly of gallium nanoparticles grown by atomic beam deposition

Light-induced structural transformations and optical nonlinearity in gallium nano-films and self-assembled nanoparticles

We report observation of an optical nonlinearity in gallium nano-particles resulting from a light-induced structural transformation in the metal which is known for its incredible polymorphism. A freshly cleaved single-mode optical fiber was put into a vacuum chamber and cooled to 100 K. The end of the fiber was exposed to a beam of gallium atoms, leading to the steady deposition of a gallium layer, thus forming a mirror made of just a few picograms of material. The gallium forms nano-particles by self-organization. These particles are relatively uniform in size, with a diameter typically between 80 and 200 nm, which depends on the thickness of the gallium film from which they formed

Potentional photomagnetic materials based on cation photochromic mononitrosyl complex of ruthenium

The synthesis of a series of novel compounds containing the photochromic mononitrosyl cation [ Ru(NH$_{3})_{5}$NO] $^{3+}$ and metal complex paramagnetic anions : [ Ru(NH$_{3})_{5}$NO] [ M(CN)$_{6}$] (M= Cr (1), Fe (2)), [ Ru(NH$_{3})_{5}$NO] [ Cr(CN)$_{5}$NO] (3), [ Ru(NH$_{3})_{5}$NO] [ M(ox)$_{3}$] (M=Cr (4), Fe (5)) is reported. The crystal structure of salt 1 is discussed. The magnetic properties of 1 and 4 compounds studied by EPR and SQUID experimental techniques are presented. Key words. Photochromism, X-ray analysis, Mononitrosyl complexes, Hexacyanometallate, Magnetic properties

Light-induced metallization in laser-deposited gallium films

We have found that mirrors prepared upon silica glass by ultrafast pulsed laser deposition of elemental gallium show a highly reproducible and fully reversible light-induced reflectivity increase. The effect is explained as being due to nonthermal light-induced metallization of gallium at the interface

Gigantic broadband optical nonlinearity in gallium films deposited by ultrafast laser ablation

Gallium-Silica interfaces have emerged as a new type of structure that combines a strong nonlinearity [1] with picosend switching-on time [2]. Here we report that the optical nonlinearity of gallium films deposited on fused silica by ultrafast pulsed laser ablation is very broadband, spanning from 480 nm to 810 nm

First observation of light-controlled self-assembly of gallium nanoparticles with narrow size dispersion

Summary form only given. We report growth processes that control the shape and size of particles as they form, through non-thermal processes, using a low-power (~ few mW) infrared diode laser. We study nanoparticle formation on the ends of optical fibers exposed to a gallium atomic-beam source under high vacuum. The results of the experiments and numerical modeling indicate that the growth of gallium nanoparticles in a laser-illuminated area is controlled through non-thermal laser-induced processes. We expect that by changing the deposition conditions (atomic beam flux, substrate temperature, etc.) and laser parameters (wavelength, power, etc.), the size, shape and spatial distribution of nanoparticles could be varied