Concept to standardize space vehicle piggyback experiment modules

Study investigates the use of spent launch vehicle stages and modules to support earth orbital operations and functions after successful completion of the primary mission. Emphasis is placed primarily on determination of those uses that afford the greatest utility with minimum possibility of degradation to the primary mission

Mass Shift and Width Broadening of J/psi in hot gluonic plasma from QCD Sum Rules

We investigate possible mass shift and width broadening of J/psi in hot gluonic matter using QCD sum rule. Input values of gluon condensates at finite temperature are extracted from lattice QCD data for the energy density and pressure. Although stability of the moment ratio is achieved only up to T/Tc ~ 1.05, the gluon condensates cause a decrease of the moment ratio, which results in change of spectral properties. Using the Breit-Wigner form for the phenomenological side, we find that mass shift of J/psi just above Tc can reach maximally 200 MeV and width can broaden to dozens of MeV.Comment: 4 pages, 5 figures, version to appear in Physical Review Letter

Critical behavior of charmonia across the phase transition: A QCD sum rule approach

We investigate medium-induced change of mass and width of J/psi and eta_c across the phase transition in hot gluonic matter using QCD sum rules. In the QCD sum rule approach, the medium effect on heavy quarkonia is induced by the change of both scalar and twist-2 gluon condensates, whose temperature dependences are extracted from the lattice calculations of energy density and pressure. Although the stability of the operator product expansion side seems to break down at T > 1.06Tc for the vector channel and T>1.04Tc for the pseudoscalar channel, we find a sudden change of the spectral property across the critical temperature Tc, which originates from an equally rapid change of the scalar gluon condensate characterized by e-3p. By parameterizing the ground state of the spectral density by the Breit-Wigner form, we find that for both J/psi and eta_c, the masses suddenly decrease maximally by a few hundreds of MeV and the widths broaden to ~100 MeV slightly above Tc. Implications for recent and future heavy ion experiments are discussed. We also carry out a similar analysis for charmonia in nuclear matter, which could serve as a testing ground for observing the precursor phenomena of the QCD phase transition. We finally discuss the possibility of observing the mass shift at nuclear matter at the FAIR project at GSI.Comment: 18 pages, 21 figures, 2 figures are added and discussion on effect of dynamical quarks is extended. version to appear in Phys.Rev.

Graphite/Larc-160 technology demonstration segment test results

A structural test program was conducted on a Celion/LARC-160 graphite/polyimide technology demonstration segment (TDS) to verify the technology. The 137 x 152 cm (54 x 60 in.) TDS simulates a full-scale section of the orbiter composite body flap design incorporating three ribs and extending from the forward cove back to the rear spar. The TDS was successfully subjected to mechanical loads and thermal environments (-170 to 316 C) simulating 100 shuttle orbiter missions. Successful completion of the test program verified the design, analysis, and fabrication methodology for bonded Gr/PI honeycomb sandwich structure and demonstration that Gr/PI composite technology readiness is established

Detecting signals of weakly first-order phase transitions in two-dimensional Potts models

We investigate the first-order phase transitions of the $q$-state Potts models with $q = 5, 6, 7$, and $8$ on the two-dimensional square lattice, using Monte Carlo simulations. At the very weakly first-order transition of the $q=5$ system, the standard data-collapse procedure for the order parameter, carried out with results for a broad range of system sizes, works deceptively well and produces non-trivial critical exponents different from the trivial values expected for first-order transitions. However, a more systematic study reveals significant drifts in the `pseudo-critical' exponents as a function of the system size. For this purpose, we employ two methods of analysis: the data-collapse procedure with narrow range of the system size, and the Binder-cumulant crossing technique for pairs of system sizes. In both methods, the estimates start to drift toward the trivial values as the system size used in the analysis exceeds a certain `cross-over' length scale. This length scale is remarkably smaller than the correlation length at the transition point for weakly first-order transitions, e.g., less than one tenth for $q=5$, in contrast to the naive expectation that the system size has to be comparable to or larger than the correlation length to observe the correct behavior. The results overall show that proper care is indispensable to diagnose the nature of a phase transition with limited system sizes.Comment: 10 pages, 7 figures. One figure has been replaced to make our claim cleare

Calculations of Branching Ratios for Radiative-Capture, One-Proton, and Two-Neutron Channels in the Fusion Reaction 209^{209}Bi+70^{70}Zn

We discuss the possibility of the non-one-neutron emission channels in the cold fusion reaction $^{70}$Zn + $^{209}$Bi to produce the element Z=113. For this purpose, we calculate the evaporation-residue cross sections of one-proton, radiative-capture, and two-neutron emissions relative to the one-neutron emission in the reaction $^{70}$Zn + $^{209}$Bi. To estimate the upper bounds of those quantities, we vary model parameters in the calculations, such as the level-density parameter and the height of the fission barrier. We conclude that the highest possibility is for the 2n reaction channel, and its upper bounds are 2.4$$ and at most less than 7.9% with unrealistic parameter values, under the actual experimental conditions of [J. Phys. Soc. Jpn. {\bf 73} (2004) 2593].Comment: 6 pages, 4 figure

Mapping Kitaev's quantum double lattice models to Levin and Wen's string-net models

We exhibit a mapping identifying Kitaev's quantum double lattice models explicitly as a subclass of Levin and Wen's string net models via a completion of the local Hilbert spaces with auxiliary degrees of freedom. This identification allows to carry over to these string net models the representation-theoretic classification of the excitations in quantum double models, as well as define them in arbitrary lattices, and provides an illustration of the abstract notion of Morita equivalence. The possibility of generalising the map to broader classes of string nets is considered.Comment: 8 pages, 6 eps figures; v2: matches published versio

Quaternionic Electroweak Theory

We explicitly develop a quaternionic version of the electroweak theory, based on the local gauge group $U(1, q)_{L}\mid U(1, c)_{Y}$. The need of a complex projection for our Lagrangian and the physical significance of the anomalous scalar solutions are also discussed.Comment: 12 pages, Revtex, submitted to J. Phys.

The S-II Injection Stage for the Mars/Venus Flyby Mission

Multiple Saturn launches have been considered as a means of placing in earth orbit the system elements required for spacecraft planetary injection. With the S-II injection stage concept evolved for this purpose, the flyby mission spacecraft and injection stage (with hydrogen and without oxygen) are assembled in earth orbit. Tankers supply liquid oxygen to the injection stage. The earth orbital mode of operation is based on delivery of payloads to orbit by use of a twostage Saturn V earth-launch system. To accomplish orbital operations, the current S-II stage can be modified for the injection stage application. Required changes are based on a minimum-modification approach. Fundamental to a S-IIB mode of planetary injection is a LOX tanker, Which is a new development. Studies show that the tanking mode offers program and mission flexibility and increased pay load margin