SOUTHERNMOST OCCURRENCE OF THE SUWANNEE COOTER, PSEUDEMYS CONCINNA SUWANNIENSIS (TESTUDINES: EMYDIDAE)

The Suwannee Cooter, Pseudemys concinna suwanniensis, the largest member of the speciose turtle family Emydidae, inhabits a small number of rivers that drain into the northeastern Gulf of Mexico along the northwest coast of Florida from just west of Tallahassee to just south of Tampa. The status of this state-protected subspecies in the southernmost of these rivers, the Alafia, is unknown and hence of conservation concern. We provide recent evidence confirming that a reproducing population still exists in this river, and review available specimens and both published and unpublished records documenting the southern limit of distribution. At least within the eastern United States, our observations also extend confirmed knowledge of the geographic occurrence of hatchling turtles overwintering in the nest southward by 285 km

Engineering Negative Differential Conductance with the Cu(111) Surface State

Low-temperature scanning tunneling microscopy and spectroscopy are employed to investigate electron tunneling from a C60-terminated tip into a Cu(111) surface. Tunneling between a C60 orbital and the Shockley surface states of copper is shown to produce negative differential conductance (NDC) contrary to conventional expectations. NDC can be tuned through barrier thickness or C60 orientation up to complete extinction. The orientation dependence of NDC is a result of a symmetry matching between the molecular tip and the surface states.Comment: 5 pages, 4 figures, 1 tabl

Classification of SUSY and non-SUSY Chiral Models from Abelian Orbifolds AdS/CFT

We classify compactifications of the type IIB superstring on AdS_{5} x S^{5}/\Gamma, where \Gamma is an abelian group of order n<= 12. Appropriate embedding of \Gamma in the isometry of S^5 yields both SUSY and non-SUSY chiral models that can contain the minimal SUSY standard model or the standard model. New non-SUSY three family models with \Gamma=Z_8 are introduced, which lead to the right Weinberg angle for TeV trinification.Comment: 12 pages, no figur

Gilbert Damping in Magnetic Multilayers

We study the enhancement of the ferromagnetic relaxation rate in thin films due to the adjacent normal metal layers. Using linear response theory, we derive the dissipative torque produced by the s-d exchange interaction at the ferromagnet-normal metal interface. For a slow precession, the enhancement of Gilbert damping constant is proportional to the square of the s-d exchange constant times the zero-frequency limit of the frequency derivative of the local dynamic spin susceptibility of the normal metal at the interface. Electron-electron interactions increase the relaxation rate by the Stoner factor squared. We attribute the large anisotropic enhancements of the relaxation rate observed recently in multilayers containing palladium to this mechanism. For free electrons, the present theory compares favorably with recent spin-pumping result of Tserkovnyak et al. [Phys. Rev. Lett. \textbf{88},117601 (2002)].Comment: 1 figure, 5page

Beyond dimension six in SM Effective Field Theory: a case study in Higgs pair production at NLO QCD

We present the NLO (two-loop) QCD corrections to Higgs boson pair production in gluon fusion within Standard Model Effective Theory (SMEFT), including also squared dimension-6 operators and double insertions of operators. The different options to truncate the EFT expansion are contrasted to a non-linear EFT approach (HEFT) and their effects are illustrated by several phenomenological examples

Beyond dimension six in SM Effective Field Theory: a case study in Higgs pair production at NLO QCD

We present the NLO (two-loop) QCD corrections to Higgs boson pair production in gluon fusion within Standard Model Effective Theory (SMEFT), including also squared dimension-6 operators and double insertions of operators. The different options to truncate the EFT expansion are contrasted to a non-linear EFT approach (HEFT) and their effects are illustrated by several phenomenological examples

Size-dependent Surface States on Strained Cobalt Nanoislands on Cu(111)

Low-temperature scanning tunneling spectroscopy over Co nanoislands on Cu(111) showed that the surface states of the islands vary with their size. Occupied states exhibit a sizeable downward energy shift as the island size decreases. The position of the occupied states also significantly changes across the islands. Atomic-scale simulations and ab inito calculations demonstrate that the driving force for the observed shift is related to size-dependent mesoscopic relaxations in the nanoislands.Comment: 4 pages, 4 figure