We investigate theoretically the dynamics of a Josephson junction in the framework of the RSJ model. We consider a junction that hosts two supercurrrent contributions: a \(2\pi\)- and a ...\(4\pi\)-periodic in phase, with intensities \(I_{2\pi}\) and \(I_{4\pi}\) respectively. We study the size of the Shapiro steps as a function of the ratio of the intensity of the mentioned contributions, i.e. \(I_{4\pi}/I_{2\pi}\). We provide detailed explanations where to expect clear signatures of the presence of the \(4\pi\)-periodic contribution as a function of the external parameters: the intensity AC-bias \(I_\text{ac}\) and frequency \(\omega_\text{ac}\). On the one hand, in the low AC-intensity regime (where \(I_\text{ac}\) is much smaller than the critical current, \(I_\text{c}\)), we find that the non-linear dynamics of the junction allows the observation of only even Shapiro steps even in the unfavorable situation where \(I_{4\pi}/I_{2\pi}\ll 1\). On the other hand, in the opposite limit (\(I_\text{ac}\gg I_\text{c}\)), even and odd Shapiro steps are present. Nevertheless, even in this regime, we find signatures of the \(4\pi\)-supercurrent in the beating pattern of the even step sizes as a function of \(I_\text{ac}\).
Euclid is a space-based survey mission from the European Space Agency designed to understand the origin of the Universe's accelerating expansion. It will use cosmological probes to investigate the ...nature of dark energy, dark matter and gravity by tracking their observational signatures on the geometry of the universe and on the cosmic history of structure formation. The mission is optimised for two independent primary cosmological probes: Weak gravitational Lensing (WL) and Baryonic Acoustic Oscillations (BAO). The Euclid payload consists of a 1.2 m Korsch telescope designed to provide a large field of view. It carries two instruments with a common field-of-view of ~0.54 deg2: the visual imager (VIS) and the near infrared instrument (NISP) which contains a slitless spectrometer and a three bands photometer. The Euclid wide survey will cover 15,000 deg2 of the extragalactic sky and is complemented by two 20 deg2 deep fields. For WL, Euclid measures the shapes of 30-40 resolved galaxies per arcmin2 in one broad visible R+I+Z band (550-920 nm). The photometric redshifts for these galaxies reach a precision of dz/(1+z) < 0.05. They are derived from three additional Euclid NIR bands (Y, J, H in the range 0.92-2.0 micron), complemented by ground based photometry in visible bands derived from public data or through engaged collaborations. The BAO are determined from a spectroscopic survey with a redshift accuracy dz/(1+z) =0.001. The slitless spectrometer, with spectral resolution ~250, predominantly detects Ha emission line galaxies. Euclid is a Medium Class mission of the ESA Cosmic Vision 2015-2025 programme, with a foreseen launch date in 2019. This report (also known as the Euclid Red Book) describes the outcome of the Phase A study.
On the basis of studies in two brothers and their double first cousin, the Kallmann syndrome (KS) is discussed as an X-linked syndrome of anosmic hypogonadotropic hypogonadism. The anosmia is thought ...to represent agenesis or hypoplasia of the olfactory lobes, the mildest form of the alobar holoprosencephaly developmental field defect; this is supported by the finding of hypotelorism in two of the patients and their mother. The endocrine defect is thought to represent a hypothalamic abnormality of the luteinizing hormone releasing hormone; borderline normal intelligence may represent another pleio-tropic CNS manifestation of the KS gene. All three affected males had unilateral renal aplasia, associated in one with ipsilateral absence of the testis. The presence of at least two developmental field defects (involving the CNS and urogenital system) makes it likely that the KS is a true multiple congenital anomaly syndrome; this is supported by the finding of additional, mostly minor, anomalies reported by other investigators. Heterozygous females may also show manifestations of anosmia, hypogonadism, possibly even internal genital malformation; however, genetic heterogeneity of anosmic hypogonadism is possible, and for the time being it is probably better to designate sporadic female cases of anosmic hypogonadism as examples of the olfacto-genital syndrome of DeMorsier. Linkage studies are urgently needed to clear up the question of genetic heterogeneity and to help develop empiric recurrence risk figures in anosmic hypogonadism.
ATF2 is a final-focus test beam line which aims to focus the low emittance beam from the ATF damping ring to a vertical size of about 37 nm and to demonstrate nanometer level beam stability. Several ...advanced beam diagnostics and feedback tools are used. In December 2008, construction and installation were completed and beam commissioning started, supported by an international team of Asian, European, and U.S. scientists. The present status and first results are described.
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