Resonance states of Ps- using correlated wave functions
Abstract We have investigated the F e 1 , 3 resonance states of positronium negative ion below the N = 3 , 4 and 5 Ps thresholds using highly correlated exponential wave functions. Resonance parameters (positions and widths) are extracted employing both the stabilization method and the complex-coordinate rotation method. In addition to many Feshbach resonances below the various Ps thresholds, we have identified two F e 1 shape resonances with one each lying above the N = 3 and N = 5 thresholds, respectively. We have also identified three F e 3 shape resonances with one lying above the N = 3 threshold and two lying above N = 4 threshold. The F e 1 , 3 shape resonances associated with N = 3 Ps threshold and some other Feshbach resonances are reported for the first time in the literature.
Dynamic dipole polarizabilities of H− and Ps− in weakly coupled plasmas
The effects of weakly coupled plasmas on the dynamic dipole polarizabilities of the H− and Ps− ions are investigated using highly correlated exponential wave functions. The Debye-Huckel shielding approach of plasma modeling is used to represent weakly coupled plasma environments. In free-atomic cases, results obtained from the present study for H− are in agreement with the available calculations and results for Ps− are reported for the first time. Frequency-dependent polarizabilities of H− and Ps− as functions of screening parameter are also presented for the first time.
The Impact of EU Unfair Contract Terms Law on U.S. Business-to-Consumer Internet Merchants
When the Court of Appeals for Versailles issued its decision in AOL France v. UFC Que Choisir2 in September 2005, it sent the message to U.S. Internet businesses that even contractual boilerplate localized for European markets may be invalid in European consumer transactions. In that case, a French consumer advocacy group challenged the terms AOL offered its French customers after AOL had made extensive revisions to its standard form contracts to respond to the concerns regarding those terms expressed in an advisory opinion by a French consumer protection agency. In 2004, a trial court invalidated nearly every term in the revised agreement; the appeals court affirmed on all counts. Subsequently, in July 2006 following concerns raised by the Office of Fair Trading (“OFT”), a United Kingdom government agency charged with “making sure markets work well for consumers,”3 Dell Corporation Limited changed its online terms and conditions to make them fairer to consumers.4 European consumer contract law had an impact in both cases. At issue for AOL France and Dell Corporation Limited was the application of France’s and the UK’s consumer contract law which is based on the Unfair Contract Terms Directive of 19945 and calls into question the validity of many of the terms that U.S. courts routinely enforce in transactions involving American consumers and merchants.