1,241 research outputs found
A mobile data acquisition system
A mobile data aquisition (MobiDAQ) was developed for the ATLAS central hadronic
calorimeter (TileCal). MobiDAQ has been designed in order to test the functionalities of the TileCal
front-end electronics and to acquire calibration data before the final back-end electronics were built
and tested. MobiDAQ was also used to record the first cosmic ray events acquired by an ATLAS
subdetector in the underground experimental area
Synchroneity of major late Neogene sea level fluctuations and paleoceanographically controlled changes as recorded by two carbonate platforms
Shallow-water carbonate systems are reliable recorders of sea level fluctuations and changes in ambient seawater conditions. Drilling results from Ocean Drilling Program (ODP) Legs 133 and 166 indicate that the timing of late Neogene sedimentary breaks triggered by sea level lowerings is synchronous in the sedimentary successions of the Queensland Plateau and the Great Bahama Bank. This synchrony indicates that these sea level changes were eustatic in origin. The carbonate platforms were also affected by contemporary, paleoceanographically controlled fluctuations in carbonate production. Paleoceanographic changes are recorded at 10.7, 3.6, and 1.7â2.0 Ma. At the Queensland Plateau, sea surface temperature shifts are documented by shifts from tropical to temperate carbonates (10.7 Ma) and vice versa (3.6 Ma); the modern tropical platform was established at 2.0â1.8 Ma. At Great Bahama Bank, changes were registered in compositional variations of platform-derived sediment, such as major occurrence of peloids (3.6 Ma) and higher rates of neritic carbonate input (1.7 Ma). The synchroneity of these changes attests to the far-field effects of modifications in the oceanographic circulation on shallow-water, low-latitude carbonate production
Reply to comment from Liotta and Rizzo on âEvolution of CO2 , SO2 , HCl and HNO3 in the volcanic plumes from Etnaâ by Voigt et al. [Geophys. Res. Lett.; 41, doi:10.1002/2013GL058974]
Editorâs Note:
The following comment and reply arise from an article
published in Geophysical Research Letters by Voigt
et al. (2014). The article addresses a volcanology topic,
and the commenters take issue with some conclusions
and offer an analysis of their own. Voigt and co-authors
have responded.
Why is this comment-and-reply being published in
the Bulletin? It is because Geophysical Research
Letters is one of a number of journals that do not offer
any published forum for discussion of the papers they
publish. This is a matter of editorial policy and a
decision for each journal.
The Bulletin of Volcanology does provide a forum for
discussion of articles published. When contacted by
Marcello Liotta with the request that the Bulletin consider
hosting a discussion of the Voigt et al. volcanology article in
GRL, I agreed to do so if the GRL authors were willing to
engage with the comment. Voigt and co-authors were willing
to do so and have been allowed a small amount of additional
space to summarize for Bulletin readers the key points of the
GRL paper under discussion before responding directly to the
comment from Liotta and Rizzo.
I hope that Bulletin readers find the discussion and reply of
interest
Uncovering dispersion properties in semiconductor waveguides to study photon-pair generation
This work was supported by the FWF through project no. I-2065-N27, the DFG Project no. SCHN1376/2-1, the ERC project EnSeNa (257531) and the State of Bavaria.We investigate the dispersion properties of ridge Bragg-reflection waveguides to deduce their phasematching characteristics. These are crucial for exploiting them as sources of parametric down-conversion (PDC). In order to estimate the phasematching bandwidth we first determine the group refractive indices of the interacting modes via FabryâPerot experiments in two distant wavelength regions. Second, by measuring the spectra of the emitted PDC photons, we gain access to their group index dispersion. Our results offer a simple approach for determining the PDC process parameters in the spectral domain, and provide important feedback for designing such sources, especially in the broadband case.Publisher PDFPeer reviewe
Isosbestic points in the spectral function of correlated electrons
We investigate the properties of the spectral function A(omega,U) of
correlated electrons within the Hubbard model and dynamical mean-field theory.
Curves of A(omega,U) vs. omega for different values of the interaction U are
found to intersect near the band-edges of the non-interacting system. For a
wide range of U the crossing points are located within a sharply confined
region. The precise location of these 'isosbestic points' depends on details of
the non-interacting band structure. Isosbestic points of dynamic quantities
therefore provide valuable insights into microscopic energy scales of
correlated systems.Comment: 16 pages, 5 figure
Archetypal Reading of Fairytales
Tema je rada arhetipsko tumaÄenje bajke. Polazne pretpostavke istraĹživanja bile su moguÄe definicije bajki unutar kojih se pokuĹĄalo smjestiti jungovsku psihoanalitiÄku teoriju o arhetipovima na primjerima razliÄitih likova svjetskih, europskih, kao i hrvatskih bajki. Ponajprije se bajka definira kao vrsta, a zatim je definiran pojam arhetipa, koji pripada psihoanalizi Carla Gustava Junga. Prema Jungovoj teoriji, arhetipovi su modeli osobnosti, âpraslikeâ i dio kolektivno nesvjesnoga te je u njima moguÄe pronaÄi simboliku za mnoge modele ponaĹĄanja svih ljudi. Cilj je rada prouÄiti psihoanalitiÄke stavove Carla Gustava Junga s obzirom na tumaÄenje arhetipova te primijeniti ta uÄenja na bajku i njezine likove.
Predstavljeni su narativni Äimbenici bajke te kako se njihova uloga uklapa u koncept arhetipskog Äitanja, a poseban je naglasak stavljen na arhetipove Jastva, Anime, Animusa, Sjene i Persone, na temelju Äijih su karakteristika i simbolike razvrstani mnogi likovi iz poznatih europskih i hrvatskih bajki. Svaki je arhetip predstavljen s psihoanalitiÄke strane, koristeÄi kao glavnu teorijsku literarnu jedinicu knjigu Jolande Jacobi Psihologija C.G.Junga, a u interpretaciji arhetipskih likova u bajkama knjigu Marie-Louise von Franz Interpretacija bajki
Scaling of magnetic fluctuations near a quantum phase transition
We use inelastic neutron scattering to measure the magnetic fluctuations in a
single crystal of the heavy fermion alloy CeCu_5.9Au_0.1 close to the
antiferromagnetic quantum critical point. The energy and temperature-dependent
spectra obey (E/T) scaling at Q near (1,0,0). The neutron data and earlier bulk
susceptibility are consistent with the form 1/X ~ f(Q)+(-iE+bT)^a, with an
anomalous exponent a=0.8. We confirm the earlier observation of quasi-low
dimensionality and show how both the magnetic fluctuations and the
thermodynamics can be understood in terms of a quantum Lifshitz point.Comment: Latex file with two postscript figure
Nearly universal crossing point of the specific heat curves of Hubbard models
A nearly universal feature of the specific heat curves C(T,U) vs. T for
different U of a general class of Hubbard models is observed. That is, the
value C_+ of the specific heat curves at their high-temperature crossing point
T_+ is almost independent of lattice structure and spatial dimension d, with
C_+/k_B \approx 0.34. This surprising feature is explained within second order
perturbation theory in U by identifying two small parameters controlling the
value of C_+: the integral over the deviation of the density of states
N(\epsilon) from a constant value, characterized by \delta N=\int d\epsilon
|N(\epsilon)-1/2|, and the inverse dimension, 1/d.Comment: Revtex, 9 pages, 6 figure
Specific Heat of a Three Dimensional Metal Near a T=0 Magnetic Transition with Dynamic Exponent z=2,3,4
We derive expressions for the universal contribution to the specific heat of
a three-dimensional metal near a zero-temperature phase transition with dynamic
exponent , or 4. The results allow a quantitative comparison of theory
to data. We illustrate the application of our results by analyzing data for
CeLuCuSi, which has been claimed to be near a quantum
critical point.Comment: 23 pages, revtex. For figures, send mail to [email protected]
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