Chiral Symmetry and N*(1440) -> N pi pi Decay

The N*(1440) -> N pi pi decay is studied by making use of the chiral reduction formula. This formula suggests a scalar-isoscalar pion-baryon contact interaction which is absent in the recent study of Hern{\'a}ndez et al. The contact interaction is introduced into their model, and is found to be necessary for the simultaneous description of g_{RN pi pi} and the pi-pi and pi-N invariant mass distributions.Comment: 12 page

Familial Takayasu arteritis - a pediatric case and a review of the literature

Takayasu arteritis (TA) is a rare chronic inflammatory disease of the aorta and its major branches. It is seen predominantly in females during the second and third decades of life, although it can occur in childhood. The aetiology of TA remains unknown. To date, familial cases of TA have been considered rare; however, a review of the literature suggests that cases are accumulating. We report a case of two sisters affected by severe TA, and review other reported familial cases

Dynamical stabilization of matter-wave solitons revisited

We consider dynamical stabilization of Bose-Einstein condensates (BEC) by time-dependent modulation of the scattering length. The problem has been studied before by several methods: Gaussian variational approximation, the method of moments, method of modulated Townes soliton, and the direct averaging of the Gross-Pitaevskii (GP) equation. We summarize these methods and find that the numerically obtained stabilized solution has different configuration than that assumed by the theoretical methods (in particular a phase of the wavefunction is not quadratic with $r$). We show that there is presently no clear evidence for stabilization in a strict sense, because in the numerical experiments only metastable (slowly decaying) solutions have been obtained. In other words, neither numerical nor mathematical evidence for a new kind of soliton solutions have been revealed so far. The existence of the metastable solutions is nevertheless an interesting and complicated phenomenon on its own. We try some non-Gaussian variational trial functions to obtain better predictions for the critical nonlinearity $g_{cr}$ for metastabilization but other dynamical properties of the solutions remain difficult to predict

Hadronic Masses and Regge Trajectories

A comprehensive phenomenological analysis of experimental data and some theoretical models is presented here (for mesons) to critically discuss how Regge trajectory parameters depend on flavor. Through analytic continuation of physical trajectories (obtained from resonance data) into the space like region, we derive the suppression factor for heavy flavor production. The case of our D Regge exchange, both for D and $\Lambda_c$ production, is considered in some detail. Good agreement with data is reached confirming that indeed the slopes of heavier flavors decrease. This result suggests that the confinement potential has a substantial dependence on the quark masses. In a simple non-relativistic model, constrained to produce linear Regge trajectories, it is shown that a linear quark mass dependence is required (in the confinement part of the potential) in order for the slope to decrease in the appropriate way.Comment: 19 pages, 9 Figures, IV Table

First Results from the KMOS Lens-Amplified Spectroscopic Survey (KLASS): Kinematics of Lensed Galaxies at Cosmic Noon

We present the first results of the KMOS Lens-Amplified Spectroscopic Survey (KLASS), a new ESO Very Large Telescope (VLT) large program, doing multi-object integral field spectroscopy of galaxies gravitationally lensed behind seven galaxy clusters selected from the HST Grism Lens-Amplified Survey from Space (GLASS). Using the power of the cluster magnification we are able to reveal the kinematic structure of 25 galaxies at $0.7 \lesssim z \lesssim 2.3$, in four cluster fields, with stellar masses $8 \lesssim \log{(M_\star/M_\odot)} \lesssim 11$. This sample includes 5 sources at $z>1$ with lower stellar masses than in any previous kinematic IFU surveys. Our sample displays a diversity in kinematic structure over this mass and redshift range. The majority of our kinematically resolved sample is rotationally supported, but with a lower ratio of rotational velocity to velocity dispersion than in the local universe, indicating the fraction of dynamically hot disks changes with cosmic time. We find no galaxies with stellar mass $<3 \times 10^9 M_\odot$ in our sample display regular ordered rotation. Using the enhanced spatial resolution from lensing, we resolve a lower number of dispersion dominated systems compared to field surveys, competitive with findings from surveys using adaptive optics. We find that the KMOS IFUs recover emission line flux from HST grism-selected objects more faithfully than slit spectrographs. With artificial slits we estimate slit spectrographs miss on average 60% of the total flux of emission lines, which decreases rapidly if the emission line is spatially offset from the continuum.Comment: Accepted for publication in Ap

Second wind of the Dulong-Petit Law at a quantum critical point

Renewed interest in 3He physics has been stimulated by experimental observation of non-Fermi-liquid behavior of dense 3He films at low temperatures. Abnormal behavior of the specific heat C(T) of two-dimensional liquid 3He is demonstrated in the occurrence of a T-independent term in C(T). To uncover the origin of this phenomenon, we have considered the group velocity of transverse zero sound propagating in a strongly correlated Fermi liquid. For the first time, it is shown that if two-dimensional liquid 3He is located in the vicinity of the quantum critical point associated with a divergent quasiparticle effective mass, the group velocity depends strongly on temperature and vanishes as T is lowered toward zero. The predicted vigorous dependence of the group velocity can be detected in experimental measurements on liquid 3He films. We have demonstrated that the contribution to the specific heat coming from the boson part of the free energy due to the transverse zero-sound mode follows the Dulong-Petit Law. In the case of two-dimensional liquid 3He, the specific heat becomes independent of temperature at some characteristic temperature of a few mK.Comment: 5 pages, 1 figur

The Grism Lens-Amplified Survey from Space (GLASS). XII. Spatially Resolved Galaxy Star Formation Histories and True Evolutionary Paths at z > 1

Modern data empower observers to describe galaxies as the spatially and biographically complex objects they are. We illustrate this through case studies of four, $z\sim1.3$ systems based on deep, spatially resolved, 17-band + G102 + G141 Hubble Space Telescope grism spectrophotometry. Using full spectrum rest-UV/-optical continuum fitting, we characterize these galaxies' observed $\sim$kpc-scale structures and star formation rates (SFRs) and reconstruct their history over the age of the universe. The sample's diversity---passive to vigorously starforming; stellar masses $\log M_*/M_\odot=10.5$ to $11.2$---enables us to draw spatio-temporal inferences relevant to key areas of parameter space (Milky Way- to super-Andromeda-mass progenitors). Specifically, we find signs that bulge mass-fractions ($B/T$) and SF history shapes/spatial uniformity are linked, such that higher $B/T$s correlate with "inside-out growth" and central specific SFRs that peaked above the global average for all starforming galaxies at that epoch. Conversely, the system with the lowest $B/T$ had a flat, spatially uniform SFH with normal peak activity. Both findings are consistent with models positing a feedback-driven connection between bulge formation and the switch from rising to falling SFRs ("quenching"). While sample size forces this conclusion to remain tentative, this work provides a proof-of-concept for future efforts to refine or refute it: JWST, WFIRST, and the 30-m class telescopes will routinely produce data amenable to this and more sophisticated analyses. These samples---spanning representative mass, redshift, SFR, and environmental regimes---will be ripe for converting into thousands of sub-galactic-scale empirical windows on what individual systems actually looked like in the past, ushering in a new dialog between observation and theory.Comment: 18 pp, 15 figs, 3 tables (main text); 5 pp, 5 figs, 1 table (appendix); Submitted to AAS Journals 1 October 201

Electrical Detection and Magnetic-Field Control of Spin States in Phosphorus-Doped Silicon

Electron paramagnetic resonance of ensembles of phosphorus donors in silicon has been detected electrically with externally applied magnetic fields lower than 200 G. Because the spin Hamiltonian was dominated by the contact hyperfine term rather than by the Zeeman terms at such low magnetic fields, superposition states $\alpha{}| \uparrow \downarrow >+\beta{}| \downarrow \uparrow >$ and $-\beta{}| \uparrow \downarrow > + \alpha{}| \downarrow \uparrow >$ were formed between phosphorus electron and nuclear spins, and electron paramagnetic resonance transitions between these superposition states and $| \uparrow \uparrow >$ or $| \downarrow \downarrow >$ states are observed clearly. A continuous change of $\alpha{}$ and $\beta{}$ with the magnetic field was observed with a behavior fully consistent with theory of phosphorus donors in silicon.Comment: 6 pages, 5 figure