3,466 research outputs found

    Detection of Supernova Neutrinos

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    Matter effects on neutrino oscillations in both, a supernova and the Earth, change the observed supernova neutrino spectra. We calculate the expected number of supernova neutrino interactions for ICARUS, SK and SNO detectors as a function of the distance which they traveled in the Earth. Calculations are performed for supernova type II at 10kpc from the Earth, using standard supernova neutrino fluxes described by thermal Fermi--Dirac distributions and the PREM I Earth matter density profile.Comment: Postscript file: 7 pages, 2 figures; tar-compressed file: tex source code, eps figures. To appear in Acta. Phys. Pol. B. Talk given at the XXVIII Mazurian Lakes School of Physics, Krzyze, Poland, August 31 - September 7, 200

    The Atheism of Heidegger, Sartre, and Thomas Aquinas

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    Theodore J. Kisiel, an engineer and philosopher, now teaching at Canisius College, was an Assistant Professor at the University of Dayton when he offered this interesting response to Father Elbert\u27s views on existentialism. The points at issue are worthy of further dialogue

    Femtoscopic signatures of collective behavior as a probe of the thermal nature of relativistic heavy ion collisions

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    Femtoscopy measures space-time characteristics of the particle emitting source created in relativistic heavy-ion collisions. It is argued that collective behavior of matter (radial flow) produces specific femtoscopic signatures. The one that is best known, the m_T dependence of the pion ``HBT radii'', can be explained by the alternative scenario of temperature gradients in an initial state thermal model. We identify others that can invalidate such alternatives, such as non-identical particle correlations and m_T scaling for particles of higher mass. Studies with a simple rescattering code show that as the interaction cross-section is increased the system develops collective behavior and becomes more thermalized at the same time, the two effects being the natural consequence of increased number of particle rescatterings. Repeating calculations with a more realistic rescattering model confirmed all of these conclusions and provided deeper insight into the mechanisms of collectivity buildup, showing a preference for a thermal model with uniform temperature.Comment: 9 pages, 11 figures ver2: added CERN report no., added references to relevant previous works on transport model

    Exploring Lifetime Effects in Femtoscopy

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    We investigate the role of lifetime effects from resonances and emission duration tails in femtoscopy at RHIC in two Blast-Wave models. We find the non-Gaussian components compare well with published source imaged data, but the value of R_out obtained from Gaussian fits is not insensitive to the non-Gaussian contributions when realistic acceptance cuts are applied to models.Comment: 5 pages, 2 figure

    Measurement of CH3_3D on Titan at Submillimeter Wavelengths

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    We present the first radio/submillimeter detection of monodeuterated methane (CH3_3D) in Titan's atmosphere, using archival data from of the Atacama Large Millimeter/submillimeter Array (ALMA). The JK=21−11J_K=2_1-1_1 and JK=20−10J_K=2_0-1_0 transitions at 465.235 and 465.250 GHz (∼0.644\sim0.644 mm) were measured at significance levels of 4.6σ4.6\sigma and 5.7σ5.7\sigma, respectively. These two lines were modeled using the Non-linear optimal Estimator for MultivariatE spectral analySIS (NEMESIS) radiative transfer code to determine the disk-averaged CH3_3D volume mixing ratio = 6.157×10−66.157\times10^{-6} in Titan's stratosphere (at altitudes >130\gt130 km). By comparison with the CH4_4 vertical abundance profile measured by Cassini-Huygens mass spectrometry, the resulting value for D/H in CH4_4 is (1.033±0.081)×10−4(1.033\pm0.081)\times10^{-4}. This is consistent with previous ground-based and in-situ measurements from the Cassini-Huygens mission, though slightly lower than the average of the previous values. Additional CH3_3D observations at higher spatial resolution will be required to determine a value truly comparable with the Cassini-Huygens CH4_4 measurements, by measuring CH3_3D with ALMA close to Titan's equator. In the post-Cassini era, spatially resolved observations of CH3_3D with ALMA will enable the latitudinal distribution of methane to be determined, making this an important molecule for further studies.Comment: 9 pages, 4 figure

    A GEANT-based study of atmospheric neutrino oscillation parameters at INO

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    We have studied the dependence of the allowed space of the atmospheric neutrino oscillation parameters on the time of exposure for a magnetized Iron CALorimeter (ICAL) detector at the India-based Neutrino Observatory (INO). We have performed a Monte Carlo simulation for a 50 kTon ICAL detector generating events by the neutrino generator NUANCE and simulating the detector response by GEANT. A chi-square analysis for the ratio of the up-going and down-going neutrinos as a function of L/EL/E is performed and the allowed regions at 90% and 99% CL are displayed. These results are found to be better than the current experimental results of MINOS and Super-K. The possibilities of further improvement have also been discussed.Comment: 8 pages, 13 figures, a new figure added, version accepted in IJMP

    EXAFS studies of prostate cancer cell lines

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    Sulphur plays a vital role in every human organism. It is known, that sulphur-bearing compounds, such as for example cysteine and glutathione, play critical roles in development and progression of many diseases. Any alteration in sulphur's biochemistry could become a precursor of serious pathological conditions. One of such condition is prostate cancer, the most frequently diagnosed malignancy in the western world and the second leading cause of cancer related death in men. The purpose of presented studies was to examine what changes occur in the nearest chemical environment of sulphur in prostate cancer cell lines in comparison to healthy cells. The Extended X-ray Absorption Fine Structure (EXAFS) spectroscopy was used, followed by theoretical calculations. The results of preliminary analysis is presented

    Ethyl cyanide on Titan: Spectroscopic detection and mapping using ALMA

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    We report the first spectroscopic detection of ethyl cyanide (C2_2H5_5CN) in Titan's atmosphere, obtained using spectrally and spatially resolved observations of multiple emission lines with the Atacama Large Millimeter/submillimeter array (ALMA). The presence of C2_2H5_5CN in Titan's ionosphere was previously inferred from Cassini ion mass spectrometry measurements of C2_2H5_5CNH+^+. Here we report the detection of 27 rotational lines from C2_2H5_5CN (in 19 separate emission features detected at >3σ>3\sigma confidence), in the frequency range 222-241 GHz. Simultaneous detections of multiple emission lines from HC3_3N, CH3_3CN and CH3_3CCH were also obtained. In contrast to HC3_3N, CH3_3CN and CH3_3CCH, which peak in Titan's northern (spring) hemisphere, the emission from C2_2H5_5CN is found to be concentrated in the southern (autumn) hemisphere, suggesting a distinctly different chemistry for this species, consistent with a relatively short chemical lifetime for C2_2H5_5CN. Radiative transfer models show that most of the C2_2H5_5CN is concentrated at altitudes 300-600 km, suggesting production predominantly in the mesosphere and above. Vertical column densities are found to be in the range (2-5)×1014\times10^{14} cm−2^{-2}.Comment: Published in 2015, ApJL, 800, L1
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