2014 A pulsed source for Cs-ions has been constructed as part of a sputter ion source in Hortig geometry. A beam of Cs-ions is extracted from a tungsten surface ionizer and bunched into pulses a few ns wide by a combination of velocity and path-of-flight modulation. It is expected that such a beam will produce intense pulses of negative ions having pulse widths in the ns range. REVUE DE PHYSIQU...

Ion-pair formation in gaseous nitromethane (CH3NO2) induced by electron transfer has been studied by investigating the products of collisions between fast potassium atoms and nitromethane molecules using a crossed molecular-beam technique. The negative ions formed in such collisions were analysed using time-of-flight mass spectroscopy. The six most dominant product anions are NO2 , O , CH3NO2 ,...

Twelve different porins from the gram-negative bacteria Escherichia coli, Salmonella typhimurium, Pseudomonas aeruginosa, and Yersinia pestis were reconstituted into lipid bilayer membranes. Most of the porins, except outer membrane protein P, formed large, water-filled, ion-permeable channels with a single-channel conductance between 1.5 and 6 nS in 1 M KCl. The ions used for probing the pore ...

Ion-pair formation in gaseous nitromethane (CH(3)NO(2)) induced by electron transfer has been studied by investigating the products of collisions between fast potassium atoms and nitromethane molecules using a crossed molecular-beam technique. The negative ions formed in such collisions were analysed using time-of-flight mass spectroscopy. The six most dominant product anions are NO(2)(-), O(-)...

The Electron Spectrometer (ELS), one of the sensors making up the Cassini Plasma Spectrometer (CAPS) revealed the existence of numerous negative ions in Titan’s upper atmosphere. The observations at closest approach ( 1000 km) show evidence for negatively charged ions up to 10,000 amu/q, as well as two distinct peaks at 2274 and 4478 amu/q, and maybe a third one at 82714 amu/q. We present the f...

The SPIDER experiment, operated at the Neutral Beam Test Facility of Consorzio RFX, Padua, hosts prototype H-/D- ion source for ITER neutral beam injectors. maximization current extracted from and minimization amount co-extracted electrons are among most relevant targets to accomplish. Cavity Ring-Down Spectroscopy diagnostic measures negative density in close acceleration system, so as have fe...

In order to realize negative ion sources and accelerators to be applicable to International Thermonuclear Experimental Reactor and JT-60 Super Advanced, a large cesium (Cs)-seeded negative ion source and a multi-aperture and multi-stage electric acceleration have been developed at Japan Atomic Energy Agency (JAEA). Long pulse production and acceleration of the negative ion beams have been indep...

Negative-ion chemical ionization mass spectrometry with a conventional combined gas chromatograph-mass spectrometer has been used for the analysis of amphetamine-like compounds. Ammonia was used as the reagent gas, which gives rise to few but specific sample-fragment ions, such as (M--1)- as the base peak, m/z 91, and a smaller peak corresponding to the end part of the side chain. Five referenc...

We report photoelectron imaging spectra of CuH and CuH 2 and their deuterated analogs. The CuH photoelectron spectrum exhibits transitions to the ground (X R) and lowest excited triplet (a R) and singlet (A R) states, with EA(CuH) 0.444(6) eV. The photoelectron spectrum of linear X Rg HCuH is dominated by a transition to the linear excited A Rg state with a 2.853 eV binding energy. It is accomp...