Neutrino-photon reactions for energies above mem_e

We show that neutrino-photon reactions above $m_e$ are dominated by the reaction $\nu \gamma \to \nu e^+ e^-$. We calculate its cross-section and see that it is larger by several orders of magnitude than the cross-sections of other neutrino-photon processes, for energies above $m_e$. We also discuss potential astrophysical and cosmological consequences.Comment: 7 pages, 2 figure

Neutrino-photon Scattering in a Magnetic Field

Previous calculations of photon-neutrino scattering in a constant background magnetic field are extended and corrected.Comment: Corrections to the labeling of the entries in Table

Computer program to generate engine inlet flow contour maps and distortion parameters

Program generates inlet contour maps with choice of mapping parameters. Contour maps are represented by symbols on picture produced by line printer. Program also generates variety of simple circumferential and radial distortion parameters that enable calculation of almost any specific distortion parameter

Signals of a superlight gravitino at hadron colliders when the other superparticles are heavy

If the gravitino (G) is very light and all the other supersymmetric particles are above threshold, supersymmetry may still be found at colliders, by looking at processes with only gravitinos and ordinary particles in the final state. We compute here the cross-sections for some distinctive signals at hadron colliders: photon plus missing energy, induced by (q antiquark -> G G photon), and jet plus missing energy, induced by (q antiquark -> G G g), (q g -> G G q), and (g g -> G G g). From the present Tevatron data, we estimate the bound m_{3/2} > 2.3 10^-5 eV on the gravitino mass, corresponding to the bound sqrt{F} > 310 GeV on the supersymmetry-breaking scale. We foresee that the upgraded Tevatron and the LHC will be sensitive to values of m_{3/2} up to 4.0 10^-5 eV and 6.2 10^-4 eV, corresponding to sqrt{F} up to 410 GeV and 1.6 TeV, respectively.Comment: 19 pages, Latex, epsfig, 13 figures This revised version supersedes that published in Nucl. Phys. B526 (1998) 136, and contains important changes. The correction of a sign error modifies the relevant partonic cross-sections. The sensitivity to the supersymmetry-breaking scale (gravitino mass) is only slightly weakene

Angular momentum content of a virtual graviton

We show that a virtual graviton has a J=0 component, which serves to cancel the J=2, J_z=0 component when the graviton is on shell. In contrast, a massive graviton has no J=0 component either on or off shell. This difference is responsible for the van Dam-Veltman-Zakharov discontinuity.Comment: 5 pages. Reference adde

The effects of high-temperature brazing and thermal cycling on the mechanical properties of Hastelloy X

Data are presented on the effects of brazing alloy, brazing operation, thermal cycling, and combinations of these on the yield strength, elongation, tensile strength, and fatigue life of thin gage Hastelloy X. These data show that brazing at 1461 K (2170 F) with a Ni-Pd-Au alloy and subsequent exposure to 200 service thermal cycles between 533 and 1144 K (500 and 1600 F) result in reduction of as much as 39 percent in yield strength, 33 percent in elongation, 14 percent in tensile strength, and 26 percent in fatigue limit of Hastelloy X, as compared to as-received materials. These property losses are primarily caused by the brazing operation rather than the subsequent service thermal cycles

Synthesis of blade flutter vibratory patterns using stationary transducers

Flutter frequency was determined and rotor vibratory amplitude and phase distributions during flutter were reconstructed from stationary aerodynamic type measurements. A previously reported optical method for measuring blade-tip displacement during flutter was extended by means of digital analysis. Displacement amplitudes and phase angles were determined based on this method. For selected blades, spectral results were also obtained from strain gage measurements. The results from these three types of measurement were compared and critically evaluated

Neutrino interactions with a weak slowly varying electromagnetic field

We derive the effective action for processes involving two neutrinos and two photons at energies much below the electron mass. We discuss several applications in which one or both photons are replaced by external fields. In particular, Cherenkov radiation and neutrino pair production in weak external fields are investigated for massive Dirac neutrinos.Comment: 7 pages, no figure

Signatures of massive sgoldstinos at e+e- colliders

In supersymmetric extensions of the Standard Model with a very light gravitino, the effective theory at the weak scale should contain not only the goldstino G, but also its supersymmetric partners, the sgoldstinos. In the simplest case, the goldstino is a gauge-singlet and its superpartners are two neutral spin-0 particles, S and P. We study possible signals of massive sgoldstinos at e+e- colliders, focusing on those that are most relevant at LEP energies. We show that the LEP constraints on e+e- => photon+S (photon+P), Z+S (Z+P) or e+e-S (e+e-P), followed by S (P) decaying into two gluon jets, can lead to stringent combined bounds on the gravitino and sgoldstino masses.Comment: 22 pages, 8 figures. Published version with note adde