Engineering PapersSearch

Engineering topics

Romero, J.

Publications and source records attributed to Romero, J..

Decay of a microsecond seniority 3 isomeric state in Hf 155

Excited states in the neutron-deficient nuclide Hf 155 have been investigated in experiments performed at the Accelerator Laboratory of the University of Jyväskylä. The Hf 155 nuclei were produced in fusion-evaporation reactions induced by beams of 295 and 315 MeV Ni 58 ions bombarding an isotopically enriched Pd 102 target and separated using the recoil mass separator MARA. An isomeric state having a half-life of 510(30) ns was discovered and is interpreted as a seniority υ = 3 , ( π h 11 / 2 2 ⊗ ν f 7 / 2 ) 27 / 2 − configuration. The γ -ray transitions emitted in the deexcitation of the isomeric state to the ground state were identified and a level scheme was constructed, from which the excitation energy of the isomer was determined to be 2581.5(10) keV. A B ( E 2 ) value of 0.45(3) W.u. was deduced for the 105.4 keV transition depopulating the isomeric state. The deduced level scheme and B ( E 2 ) value are compared with systematics and shell-model calculations. Published by the American Physical Society 2024

Physics

First realisation of the Space Absolute Radiometric Reference (SARR) during the ATLAS 2 flight period

A number of different solar constant observations all made from space during the ATLAS 2 mission have been gathered and compared to each other. The Sun did not have a single sunspot during several days. As eight of the radiometric channels were all within 0.1%, the mean of the observations has been used to determine a set of adjustment factors providing de facto the definition of the Space Absolute Radiometric Reference (SARR). The differential absolute radiometers of Solar Constant (SOLCON) experiment and the Solar Variability-1 (SOVA 1) experiment, as well as the SOVA 2 and Active Cavity Radiometer (ACR) radiometers that have been brought back to the Earth may, if used in the same conditions, reproduce and maintain the SARR for the future.

Crommelynck, D.

NASA OAST and its role in space technology development

Several new programs, efforts in space research and technology, are introduced that the Office of Aeronautics and Space Technology has begun to support. The four key issues that currently are consuming NASA's energies and should be of great concern are listed. NASA is placing its emphasis in space on: (1) reconstituting the Shuttle capability; (2) maintaining the space station momentum; (3) resolving the current science mission backlog; and (4) rebuilding the technology base. Ways of implementing and funding these issues are discussed.

Romero, J.

Space Station utilization for technology purposes

The role of the Space Station in in-space technology research and development is discussed. The categorizing of research and technology experiments, which is required in order to provide the proper facilities for the experiments, is described. The use of the Space Station, itself, as an experiment is studied; instrumented large space structure experiments, environmental interactions, human-machine interface, and evolutionary technology validation can be conducted by the Space Station. The necessary conditions for the Space Station to function as a research and technology facility are analyzed. The Space Station design and planning considerations, in order to meet research and technology objectives and support requirements, are investigated.

Anderson, J. L.