Calculation of High Energy Neutrino-Nucleon Cross Sections and Uncertainties Using the MSTW Parton Distribution Functions and Implications for Future Experiments

We present a new calculation of the cross sections for charged current (CC) and neutral current (NC) $\nu N$ and $\bar{\nu} N$ interactions in the neutrino energy range $10^{4}<E_{\nu}<10^{12}$ GeV using the most recent MSTW parton distribution functions (PDFs), MSTW 2008. We also present the associated uncertainties propagated from the PDFs, as well as parametrizations of the cross section central values, their uncertainty bounds, and the inelasticity distributions for ease of use in Monte Carlo simulations. For the latter we only provide parametrizations for energies above $10^7$ GeV. Finally, we assess the feasibility of future neutrino experiments to constrain the $\nu N$ cross section in the ultra-high energy (UHE) regime using a technique that is independent of the flux spectrum of incident neutrinos. A significant deviation from the predicted Standard Model cross sections could be an indication of new physics, such as extra space-time dimensions, and we present expected constraints on such models as a function of the number of events observed in a future subterranean neutrino detector.Comment: 20 pages, 13 figures, 5 tables, published in Phys.Rev.D. This version fixes a typo in Equation 16 of the publication. Also since version v1, the following changes are in v2 and also in the published version: tables with cs values, parametrization of the y distribution at low-y improved, the discussions on likelihood and also earth absorption are expanded, added a needed minus sign in Eq. 17 of v

Gravitational Wave Emission from the Single-Degenerate Channel of Type Ia Supernovae

The thermonuclear explosion of a C/O white dwarf as a Type Ia supernova (SN Ia) generates a kinetic energy comparable to that released by a massive star during a SN II event. Current observations and theoretical models have established that SNe Ia are asymmetric, and therefore--like SNe II--potential sources of gravitational wave (GW) radiation. We perform the first detailed calculations of the GW emission for a SN Ia of any type within the single-degenerate channel. The gravitationally-confined detonation (GCD) mechanism predicts a strongly-polarized GW burst in the frequency band around 1 Hz. Third-generation spaceborne GW observatories currently in planning may be able to detect this predicted signal from SNe Ia at distances up to 1 Mpc. If observable, GWs may offer a direct probe into the first few seconds of the SNe Ia detonation.Comment: 8 pages, 4 figures, Accepted by Physical Review Letter

Effect of transient pinning on stability of drops sitting on an inclined plane

We report on new instabilities of the quasi-static equilibrium of water drops pinned by a hydrophobic inclined substrate. The contact line of a statically pinned drop exhibits three transitions of partial depinning: depinning of the advancing and receding parts of the contact line and depinning of the entire contact line leading to the drop's translational motion. We find a region of parameters where the classical Macdougall-Ockrent-Frenkel approach fails to estimate the critical volume of the statically pinned inclined drop

Crystal structure and revised chemical formula for burckhardtite, Pb_2(Fe^(3+)Te^(6+))[AlSi_3O_8]O_6: a double-sheet silicate with intercalated phyllotellurate layers

The crystal structure of burckhardite from the type locality, Moctezuma, Sonora, Mexico, has been refined to R_1 = 0.0362 and wR_2 = 0.0370 for 215 reflections with I > 2σ(I). Burckhardtite is trigonal, space group P3lm, with the unit-cell parameters ɑ = 5.2566(5) Å, c = 13.0221(10) Å, V = 311.62(5) Å3 and Z = 1 for the ideal formula unit Pb_2(Fe^(3+)Te^(6+))[AlSi_3O_8]O_6. There is no long-range order of (Fe^(3+), Te^(6+)) or (Al^(3+), Si^(4+)). New microprobe data were used to estimate site scattering factors, and Raman spectroscopic data showed no evidence of O–H stretching bands. Burckhardtite is not closely related to the micas, as supposed previously, but is a double-sheet silicate in which the aluminosilicate anion resembles that of minerals such as cymrite and kampfite. The [(Fe^(3+)Te^(6+))O_6]^(3−) part of the structure is not bonded directly to the aluminosilicate layer, but forms a discrete anionic phyllotellurate layer that alternates with the [AlSi_3O_8]^− double sheets. Similar phyllotellurate layers are known from several synthetic phases. In burckhardtite, Pb^(2+) cations intercalate between phyllosilicate and phyllotellurate layers, forming a Pb_2[FeTeO_6] module that is topologically similar to a slab of the structure of rosiaite, Pb[Sb_2O_6]. The crystal symmetry, structure, classification as a double-sheet silicate and chemical formula, including the determination of the 6+ valence of Te and absence of essential H_2O, are all new findings for the mineral

The relationship between mineral composition, crystal structure and paragenetic sequence: the case of secondary Te mineralization at the Bird Nest drift, Otto Mountain, California, USA

An unusually diverse array of 25 secondary Te oxysalt minerals has been documented from Otto Mountain, California, and 18 of these from the Bird Nest drift sublocality. A paragenetic sequence for these minerals is proposed, using observed overgrowth relationships plus spatial association data and data from other localities. Apart from Te and O, the components Pb, Cu and H are essential in the majority of the minerals. The atomic Cu/Te ratio decreases through the paragenetic sequence. This, and the occurrence of minerals with additional components such as Cl^–, CO_3^(2–), SO_4^(2–) and Fe^(3+) at an intermediate stage, suggests nonmonotonic evolution of the parent fluids, reflecting differing access to or spatial distribution of various components. For the minerals with known crystal structures, two alternative 'structural units' were identified, one consisting only of the Te^(4+) or Te^(6+) oxyanion, while the other also included small, strongly-bound cations such as Cu^(2+). The degree of polymerization for the Te oxyanion correlated with the paragenetic sequence: the monomeric tellurate anions of early minerals were replaced progressively by dimers, chains and sheet structures, which may relate to a decreasing abundance of the 'network modifying' Cu^(2+) cation, analogous to Bowen's discontinuous reaction series in igneous rock-forming silicates. No relationship was seen between paragenetic order and the larger type of structural unit, or structural complexity as defined by information content. This contrasts with results in the literature for evaporite sulfates and pegmatite phosphates. While structure–paragenesis relationships may be widespread, the exact nature of such relationships may be different for different chemical systems and different paragenetic environments

Trapped surfaces in prolate collapse in the Gibbons-Penrose construction

We investigate existence and properties of trapped surfaces in two models of collapsing null dust shells within the Gibbons-Penrose construction. In the first model, the shell is initially a prolate spheroid, and the resulting singularity forms at the ends first (relative to a natural time slicing by flat hyperplanes), in analogy with behavior found in certain prolate collapse examples considered by Shapiro and Teukolsky. We give an explicit example in which trapped surfaces are present on the shell, but none exist prior to the last flat slice, thereby explicitly showing that the absence of trapped surfaces on a particular, natural slicing does not imply an absence of trapped surfaces in the spacetime. We then examine a model considered by Barrabes, Israel and Letelier (BIL) of a cylindrical shell of mass M and length L, with hemispherical endcaps of mass m. We obtain a "phase diagram" for the presence of trapped surfaces on the shell with respect to essential parameters $\lambda \equiv M/L$ and $\mu \equiv m/M$. It is found that no trapped surfaces are present on the shell when $\lambda$ or $\mu$ are sufficiently small. (We are able only to search for trapped surfaces lying on the shell itself.) In the limit $\lambda \to 0$, the existence or nonexistence of trapped surfaces lying within the shell is seen to be in remarkably good accord with the hoop conjecture.Comment: 22 pages, 6 figure

NLO BFKL Equation, Running Coupling and Renormalization Scales

I examine the solution of the BFKL equation with NLO corrections relevant for deep inelastic scattering. Particular emphasis is placed on the part played by the running of the coupling. It is shown that the solution factorizes into a part describing the evolution in Q^2, and a constant part describing the input distribution. The latter is infrared dominated, being described by a coupling which grows as x decreases, and thus being contaminated by infrared renormalons. Hence, for this part we agree with previous assertions that predictive power breaks down for small enough x at any Q^2. However, the former is ultraviolet dominated, being described by a coupling which falls like 1/(\ln(Q^2/\Lambda^2) + A(\bar\alpha_s(Q^2)\ln(1/x))^1/2)with decreasing x, and thus is perturbatively calculable at all x. Therefore, although the BFKL equation is unable to predict the input for a structure function for small x, it is able to predict its evolution in Q^2, as we would expect from the factorization theory. The evolution at small x has no true powerlike behaviour due to the fall of the coupling, but does have significant differences from that predicted from a standard NLO in alpha_s treatment. Application of the resummed splitting functions with the appropriate coupling constant to an analysis of data, i.e. a global fit, is very successful.Comment: Tex file, including a modification of Harvmac, 46 pages, 8 figures as .ps files. Correction of typos, updating of references, very minor corrections to text and fig.

Ex Situ Dual Hypothermic Oxygenated Machine Perfusion for Human Split Liver Transplantation

Liver splitting allows the opportunity to share a deceased graft between 2 recipients but remains underutilized. We hypothesized that liver splitting during continuous dual hypothermic oxygenated machine perfusion (DHOPE) is feasible, with shortened total cold ischemia times and improved logistics. Here, we describe a left lateral segment (LLS) and extended right lobe (ERL) liver split procedure during continuous DHOPE preservation with subsequent transplantation at 2 different centers. Methods: After transport using static cold storage, a 51-year-old brain death donor liver underwent end-ischemic DHOPE. During DHOPE, the donor liver was maintained 106 kPa. An ex situ ERL/LLS split was performed with continuing DHOPE throughout the procedure to avoid additional ischemia time. Results: Total cold ischemia times for the LLS and ERL were 205 minutes and 468 minutes, respectively. Both partial grafts were successfully transplanted at 2 different transplant centers. Peak aspartate aminotransferase and alanine aminotransferase were 172 IU/L and 107 IU/L for the LLS graft, and 839 IU/L and 502 IU/L for the ERL graft, respectively. The recipient of the LLS experienced an episode of acute cellular rejection. The ERL transplantation was complicated by severe acute pancreatitis with jejunum perforation requiring percutaneous drainage and acute cellular rejection. No device-related adverse events were observed. Conclusions: Liver splitting during continuous DHOPE preservation is feasible, has the potential to substantially shorten cold ischemia time and may optimize transplant logistics. Therefore liver splitting with DHOPE can potentially improve utilization of split liver transplantation