6,161 research outputs found
Taxonomy and Ecology of the Inconnu, Stenodus Leucichthys Nelma, in Alaska
A taxonomic and life history study of the inconnu was carried out on populations from the Kobuk, Chatanika, and upper Yukon Rivers, and Selawik, Alaska. Data on 24 morphological measurements and 11 meristic counts show little difference among: 1) males and females; 2) young and older inconnu; and 3) fish from the upper Yukon River, Chatanika River, Selawik, and Kobuk River in Alaska and the Ob River, USSR. Based on close agreement of these counts and measurements, the inconnu in Alaska is designated as Stenodus leufifhthys nelma (Pallas). For arctic fish, the inconnu exhibits a rapid growth rate. Growth rates for males and females are similar, but females live longer than males. Alaskan inconnu become sexually mature quite late in life (for Selawik males, 9 years; females, 10 years). Spawning behavior is described. Spawning occurred in the Kobuk River above Kobuk the last days of September at water temperatures betwen 1/4 and 4.6 C. Older inconnu are mainly piscivorous while the younger fish feed on invertebrates and fish. The least cisco, Coregonus sardinella, was the main food item of the Selawik inconnu. The estimated catch in Northwest Alaska in 1965 was between 34,200 and 37,000 fish, 85% of which were taken for subsistence
New results from fluctuation analysis in NA49 at the CERN SPS
The exploration of the phase diagram of strongly interacting matter,
particularly the study of the phase transition from hadronic to partonic matter
and the search for a hypothetical critical endpoint of the first order
transition line, is one of the most challenging tasks in present heavy ion
physics.
In this talk new results on chemical (particle ratio), transverse momentum,
multiplicity and azimuthal angle fluctuations will be presented. We also
discuss their connection to the onset of deconfinement and to the critical
endpoint.Comment: The Proceedings of the International Conference "Critical Point and
Onset of Deconfinement - CPOD 2011", Wuhan, November 7-11, 201
Three charged particles in the continuum. Astrophysical examples
We suggest a new adiabatic approach for description of three charged
particles in the continuum. This approach is based on the Coulomb-Fourier
transformation (CFT) of three body Hamiltonian, which allows to develop a
scheme, alternative to Born-Oppenheimer one.
The approach appears as an expansion of the kernels of corresponding integral
transformations in terms of small mass-ratio parameter. To be specific, the
results are presented for the system in the continuum. The wave function
of a such system is compared with that one which is used for estimation of the
rate for triple reaction which take place as a step of
-cycle in the center of the Sun. The problem of microscopic screening for
this particular reaction is discussed
Wave Dynamical Chaos in a Superconducting Three-Dimensional Sinai Billiard
Based on very accurate measurements performed on a superconducting microwave
resonator shaped like a desymmetrized three-dimensional (3D) Sinai billiard, we
investigate for the first time spectral properties of the vectorial Helmholtz,
i.e. non-quantum wave equation for a classically totally chaotic and
theoretically precisely studied system. We are thereby able to generalize some
aspects of quantum chaos and present some results which are consequences of the
polarization features of the electromagnetic waves.Comment: 4 pages RevTex; 4 postscript figures; to be published in Phys. Rev.
Lett.; Info: [email protected]
Coupled Microwave Billiards as a Model for Symmetry Breaking
Two superconducting microwave billiards have been electromagnetically coupled
in a variable way. The spectrum of the entire system has been measured and the
spectral statistics analyzed as a function of the coupling strength. It is
shown that the results can be understood in terms of a random matrix model of
quantum mechanical symmetry breaking -- as e.g. the violation of parity or
isospin in nuclear physics.Comment: 4 pages, 5 figure
Search for the onset of baryon anomaly at RHIC-PHENIX
The baryon production mechanism at the intermediate (2 - 5 GeV/) at
RHIC is still not well understood. The beam energy scan data in Cu+Cu and Au+Au
systems at RHIC may provide us a further insight on the origin of the baryon
anomaly and its evolution as a function of . In 2005 RHIC
physics program, the PHENIX experiment accumulated the first intensive low beam
energy data in Cu+Cu collisions. We present the preliminary results of
identified charged hadron spectra in Cu+Cu at = 22.5 and 62.4
GeV using the PHENIX detector. The centrality and beam energy dependences of
(anti)proton to pion ratios and the nuclear modification factors for charged
pions and (anti)protons are presented.Comment: 5 pages, 9 figures, proceedings for Hot Quarks 2006 workshop,
Villasimius, Sardinia, Italy, May 15 - 20, 2006. Proceedings of the
conference will be published in The European Physical Journal
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