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[en] We report on the first search for extraterrestrial neutrino-induced cascades in IceCube. The analyzed data were collected in the year 2007 when 22 detector strings were installed and operated. We will discuss the analysis methods used to reconstruct cascades and to suppress backgrounds. Simulated neutrino signal events with a E-2 energy spectrum, which pass the background rejection criteria, are reconstructed with a resolution Delta(log E) ∼ 0.27 in the energy range from ∼ 20 TeV to a few PeV. We present the range of the diffuse flux of extra-terrestrial neutrinos in the cascade channel in IceCube within which we expect to be able to put a limit.
[en] This talk covers a general but highly subjective overview of the expectation for new accelerator development. An updated version of the Livingston chart demonstrates the exponential growth in time of the equivalent laboratory energy of accelerators. A similar Livingston chart pertaining only to electron-positron colliders shows an exponential growth but in the past only one technology - electron-positron storage rings - have been responsible for this development. The question addressed is whether the type of exponential growth reflected by these two charts can be sustained in the future
[en] Wavefront errors of rotationally parabolic refractive X-ray lenses made of beryllium (Be CRLs) have been recovered for various lens sets and X-ray beam configurations. Due to manufacturing via an embossing process, aberrations of individual lenses within the investigated ensemble are very similar. By deriving a mean single-lens deformation for the ensemble, aberrations of any arbitrary lens stack can be predicted from the ensemble with σ¯ = 0.034λ. Using these findings the expected focusing performance of current Be CRLs are modeled for relevant X-ray energies and bandwidths and it is shown that a correction of aberrations can be realised without prior lens characterization but simply based on the derived lens deformation. As a result, the performance of aberration-corrected Be CRLs is discussed and the applicability of aberration-correction demonstrated over wide X-ray energy ranges.
[en] The gamma ray spectrum of plutonium contains measurable gamma rays ranging in energy from 60 keV to above 1 MeV. The FRAM gamma ray isotopic analysis code can analyze data from all types of HPGe detectors in this energy range typically using planar detectors in the energy range 60-210 keV or 120-451 keV and using coaxial detectors in the energy ranges 120-451 keV or 200-1001 keV. The statistical measurement precision depends upon the detector/energy range combination as well as the characteristics of the sample and any addition filters. In this paper we carry out the optimization of measurement precision for the important case of a multi-kg sample of low bumup PuO2 contained in a DOE 3013 Standard-compatible long-teml storage container.
[en] Non-standard interactions (NSI) between neutrinos and matter at long-baseline experiments could make determination of the CP-violating phase ambiguous due to interference with additional complex phases. Such degeneracies are often studied in the context of specific experiments and a few parameter choices, leaving it unclear how to extract a general understanding of when two sets of parameters may be degenerate or how different types of experiments in principle combine to lift such a degeneracy. This work complements detailed simulations of individual experiments by showing how underlying parameters relate to degeneracies as represented on a biprobability plot. We show how a range of energies near the oscillation maximum separates some degenerate probabilities along the CP-conserving direction of biprobability space according to , while near degenerate probabilities are separated along the CP-violating direction according to . We apply this to the experimental hints that suggest to see that this could also be consistent with or π. The baseline and energy range characteristic of DUNE provides some resolution, but a further improvement comes from beams a few degrees off-axis at ≳1000 km baselines, including some proposed sites for T2HKK.
[en] To obtain the resonance parameters in a single energy range up to 2.5 keV neutron energy and the corresponding covariance matrix, a reevaluation of 239Pu was performed with the analysis code SAMMY. The most recent experimental data were analyzed in the energy range thermal to 2.5 keV. The experimental data were renormalized, aligned on a common energy scale, and corrected for residual background. Average neutron transmission and cross sections calculated with the new resonance parameters were compared to the corresponding experimental data and to ENDF/B-VI.
[en] Since 1930 the energy of accelerators had grown by an order of magnitude roughly every 7 years. Like all exponential growths, be they human population, the size of computers, or anything else, this eventually will have to come to an end. When will this happen to the growth of the energy of particle accelerators and colliders. Fortunately, as the energy of accelerators has grown the cost per unit energy has decreased almost as fast as has the increase in energy. The result is that while the energy has increased so dramatically the cost per new installation has increased only by roughly an order of magnitude since the 1930's (corrected for inflation), while the number of accelerators operating at the frontier of the field has shrunk. As is shown in the by now familiar Livingston chart this dramatic decrease in cost has been achieved largely by a succession of new technologies, in addition to the more moderate gains in efficiency due to improved design, economies of scale, etc. We are therefore facing two questions: (1) Is there good reason scientifically to maintain the exponential growth, and (2) Are there new technologies in sight which promise continued decreases in unit costs. The answer to the first question is definitely yes; the answer to the second question is maybe
[en] The Nuclotron-based Ion Collider fAcility (NICA) is a new accelerator complex being constructed at JINR. It is designed for collider experiments with ions and protons and has to provide ion-ion (Au79+) and ion-proton collisions in the energy range 1 (dividedby) 4.5 GeV/n and collisions of polarized proton-proton and deuteron-deuteron beams. Collider conceptions with constant γtr and with possibility of its variation are considered. The ring has the racetrack shape with two arcs and two long straight sections. Its circumference is about 450m. The straight sections are optimized to have β* ∼ 35cm in two IPs and a possibility of final betatron tune adjustment.
[en] Highlights: • The vertical ionization energies of a number of photoelectron bands are determined. • The photoelectron spectra indicate the predominance of one conformer of THFA. • The threshold photoelectron spectrum shows contribution of autoionization processes. Photoelectron spectra of α-tetrahydrofurfuryl alcohol (THFA) molecules, the threshold spectrum and spectra for constant photoelectron energies, have been measured over the photon energy range 9–25 eV. Analysis of the photoelectron spectra has allowed overlapping photoionization bands to be separated, tentatively assigned and their vertical photoionization energies to be determined. These energies are compared with existing theoretical calculations. The photoelectron spectra indicate the predominance of one conformer in the population of gas-phase THFA.
[en] A search for diffuse neutrinos with energies in excess of 105 GeV is conducted with AMANDA-II data recorded between 2000 and 2002. Above 107 GeV, the Earth is essentially opaque to neutrinos. This fact, combined with the limited overburden of the AMANDA-II detector (roughly 1.5 km), concentrates these ultra high-energy neutrinos at the horizon. The primary background for this analysis is bundles of downgoing, high-energy muons from the interaction of cosmic rays in the atmosphere. No statistically significant excess above the expected background is seen in the data, and an upper limit is set on the diffuse all-flavor neutrino flux of E2 Φ90%CL < 2.7 x 10-7 GeV cm-2s-1 sr-1 valid over the energy range of 2 x 105 GeV to 109 GeV. A number of models which predict neutrino fluxes from active galactic nuclei are excluded at the 90% confidence level