13,257 research outputs found
On the low energy limit of one loop photon-graviton amplitudes
We present first results of a systematic study of the structure of the low
energy limit of the one-loop photon-graviton amplitudes induced by massive
scalars and spinors. Our main objective is the search of KLT-type relations
where effectively two photons merge into a graviton. We find such a relation at
the graviton-photon-photon level. We also derive the diffeomorphism Ward
identity for the 1PI one graviton - N photon amplitudes.Comment: 14 pages, 1 figure. Final version to be published in Physics Letters
Apollo particles and fields subsatellite magnetometer experiment
The results of the Apollo 15 subsatellite magnetometer experiment are reported. The magnetometer is described including the operation, and specifications. Orbit plots presented are altitude versus time, selenographic longitude versus latitude, and the ecliptic projection of the earth-moon system. The lunar magnetic field, solar wind interaction with the moon, the transfer function of the moon, and the plasma sheet interaction with the moon are discussed
Static feed water electrolysis module
An advanced static feed water electrolysis module (SFWEM) and associated instrumentation for generating breathable O2 was developed. The system also generates a H2 byproduct for use in an air revitalization system for O2 recovery from metabolic CO2. Special attention was given to: (1) eliminating water feed compartment degassing, (2) eliminating need for zero gravity condenser/separators, (3) increasing current density capability, and (4) providing a self contained module so that operation is independent of laboratory instrumentation and complicated startup/shutdown procedures
Advanced combined iodine dispenser and detector
A total weight of 1.23 kg (2.7 lb), a total volume of 1213 cu m (74 cu in), and an average power consumption of 5.5W was achieved in the advanced combined iodine dispenser/detector by integrating the detector with the iodine source, arranging all iodinator components within a compact package and lowering the parasitic power to the detector and electronics circuits. These achievements surpassed the design goals of 1.36 kg (3.0 lb), 1671 cu m (102 cu in) and 8W. The reliability and maintainability were improved by reducing the detector lamp power, using an interchangeable lamp concept, making the electronic circuit boards easily accessible, providing redundant water seals and improving the accessibility to the iodine accumulator for refilling. The system was designed to iodinate (to 5 ppm iodine) the fuel cell water generated during 27 seven-day orbiter missions (equivalent to 18,500 kg (40,700 lb) of water) before the unit must be recharged with iodine crystals
Analytic continuation of the Hurwitz Zeta Function with physical application
A new formula relating the analytic continuation of the Hurwitz zeta function
to the Euler gamma function and a polylogarithmic function is presented. In
particular, the values of the first derivative of the real part of the analytic
continuation of the Hurwitz zeta function for even negative integers and the
imaginary one for odd negative integers are explicitly given. The result can be
of interest both on mathematical and physical side, because we are able to
apply our new formulas in the context of the Spectral Zeta Function
regularization, computing the exact pair production rate per space-time unit of
massive Dirac particles interacting with a purely electric background field.Comment: Replaced version, minor changes. 9 pages, to be published in J. Math.
Phy
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