Atomic site sensitive processes in low energy ion-dimer collisions

Electron capture processes for low energy Ar9+ ions colliding on Ar2 dimer targets are investigated, focusing attention on charge sharing as a function of molecule orientation and impact parameter. A preference in charge-asymmetric dissociation channels is observed, with a strong correlation between the projectile scattering angle and the molecular ion orientation. The measurements provide here clear evidences that projectiles distinguish each atom in the target and, that electron capture from near-site atom is favored. Monte Carlo calculations based on the classical over-the-barrier model, with dimer targets represented as two independent atoms, are compared to the data. They give a new insight into the dynamics of the collision by providing, for the di erent electron capture channels, the two-dimensional probability maps p(~b), where ~b is the impact parameter vector in the molecular frame

Anion emission from water molecules colliding with positive ions: Identification of binary and many-body processes

It is shown that negative ions are ejected from gas-phase water molecules when bombarded with positive ions at keV energies typical of solar-wind velocities. This finding is relevant for studies of planetary and cometary atmospheres, as well as for radiolysis and radiobiology. Emission of both H- and heavier (O- and OH-) anions, with a larger yield for H-, was observed in 6.6-keV 16O+ + H2O collisions. The ex-perimental setup allowed separate identification of anions formed in collisions with many-body dynamics from those created in hard, binary collisions. Most of the ani-ons are emitted with low kinetic energy due to many-body processes. Model calcu-lations show that both nucleus-nucleus interactions and electronic excitations con-tribute to the observed large anion emission yield.Comment: 5 pages, 4 figure

Diphoton Production at Hadron Colliders and New Contact Interactions

We explore the capability of the Tevatron and LHC to place limits on the possible existence of flavor-independent $q \bar q \gamma\gamma$ contact interactions which can lead to an excess of diphoton events with large invariant masses. Assuming no departure from the Standard Model is observed, we show that the Tevatron will eventually be able to place a lower bound of 0.5-0.6 TeV on the scale associated with this new contact interaction. At the LHC, scales as large as 3-6 TeV may be probed with suitable detector cuts and an integrated luminosity of $100 fb^{-1}$.Comment: LaTex, 12pages plus 5 figures(available on request), SLAC-PUB-657

Louis-Ferdinand Céline, literary genius or national pariah? Defining moral parameters for influential cultural figures, post- Charlie Hebdo

In January 2011 the French Minister of Culture, Frédéric Mitterrand, withdrew Louis-Ferdinand Céline from a list of famous French authors specifically selected for a national celebration of culture. This bold decision polarized opinion: while many welcomed Mitterrand’s intervention, a number of prominent writers, some of them Jewish, opposed it on the grounds that Céline’s abhorrent political beliefs – expressed in three anti-Semitic pamphlets and his flirtation with Nazism- should in no way detract from his literary genius. In the light of this controversy, and of the rise in anti-Semitism following the Charlie Hebdo attacks of January 2015, this paper proposes Céline as a vital case study of the moral parameters a democratic nation should apply to a culturally important figure whose political views are deemed unacceptably reactionary

Somatostatin triggers rhythmic electrical firing in hypothalamic GHRH neurons

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Constraints on Four Fermion Contact Interactions from Precise Electroweak Measurements

We establish constraints on a general four-fermion contact interaction from precise measurements of electroweak parameters. We compute the one-loop contribution for the leptonic $Z$ width, anomalous magnetic, weak-magnetic, electric and weak dipole moments of leptons in order to extract bounds on the energy scale of these effective interactions.Comment: 16 pages, RevTeX, two figure

First Measurement of Pure Electron Shakeoff in the β Decay of Trapped 6He+ Ions

Expérience GANIL/SPIRAL/LIRATThe electron shakeoff probability of 6Li2+ ions resulting from the β- decay of 6He+ ions has been measured with high precision using a specially designed recoil ion spectrometer. This is the first measurement of a pure electron shakeoff following nuclear β decay, not affected by multielectron processes such as Auger cascades. In this ideal textbook case for the application of the sudden approximation, the experimental ionization probability was found to be Psoexp=0.023 39(36) in perfect agreement with simple quantum mechanical calculations

Effective-Lagrangian approach to precision measurements: the anomalous magnetic moment of the muon

We investigate the use of effective Lagrangians to describe the effects on high-precision observables of physics beyond the Standard Model. Using the anomalous magnetic moment of the muon as an example, we detail the use of effective vertices in loop calculations. We then provide estimates of the sensitivity of new experiments measuring the muon's $g - 2$ to the scale of physics underlying the Standard Model.Comment: 22 pages, 1 figure, PHYZZX & EPSF, report #s UCRHEP-T98, UM_TH-92-17, and NSF-ITP-92-122I Revision: The paper will now TeX properly; the content is unchange