Properties of simple atoms and ions Semiannual report, 1 Jul. - 31 Dec. 1968

Optical excitation and decay of helium atom, and relaxation of excited alkali ato

Research on the properties and interactions of simple atomic and ionic systems

Simple ionic systems were studied, such as metastable autoionizing states of the negative He ion, two-photon decay spectrum of metastable He ion, optical excitation with low energy ions, and lifetime measurements of singly ionized Li and metastable He ion. Simple atomic systems were also investigated. Metastable autoionizing atomic energy levels in alkali elements were included, along with lifetime measurements of Cr-53, group 2A isotopes, and alkali metal atoms using level crossing and optical double resonance spectroscopy

Research investigation directed toward extending the useful range of the electromagnetic spectrum Third quarterly progress report, Jun. 16 - Sep. 15, 1965

Investigations in astronomy, solid state physics, optical masers, atomic physics, and radioactive atoms for electromagnetic application

X-ray astronomy

Various experiments in X-ray astronomy are described. The occurrence of lunar occultations of the Crab Nebula were utilized to determine the spatial distribution of X-ray emitting regions in the nebula. Study of the Cygnus Loop included a search for a central X-ray point source for the area and measurement of the energy spectrum of the flux from the supernova remnant. The X-ray morphology of the Perseus cluster of galaxies was studied. X-ray spectra of different points in the cluster were also obtained. In addition, the construction of a high resolution gas fluorescence proportional counter for application to X-ray astronomy is discussed

Multidisciplinary research in the space sciences. Scope B: Experimental X-ray astronomy

A research program to design and develop instruments suitable for rocket-borne X-ray astronomy experiments is discussed. Successful designs that were implemented are summarized. The designs include the following: (1) a large area modular X-ray focusing system, (2) incoherent scattering polarimeters, (3) Bragg crystal spectrometers and polarimeters, and (4) a focusing collector for long wavelength. The applications of these instruments to the observation of X-ray sources in rocket-borne experiments are analyzed

Data reduction and analysis for the graphite crystal X-ray spectrometer and polarimeter experiment flown aboard OSO-8 spacecraft

The documentation and software programs developed for the reception, initial processing (quickbook), and production analysis of data obtained by solar X-ray spectroscopy, stellar spectroscopy, and X-ray polarimetry experiments on OSO-8 are listed. The effectiveness and sensitivity of the Bragg crystal scattering instruments used are assessed. The polarization data polarimetric data obtained shows that some X-ray sources are polarized and that a larger polarimeter of this type is required to perform the measurements necessary to fully understand the physics of X-ray sources. The scanning Bragg crystal spectrometer was ideally suited for studying rapidly changing solar conditions. Observations of the Crab Nebula and pulsar, Cyg X-1, Cyg X-2, Cyg X-3, Sco X-1, Cen X-3, and Her X-1 are discussed as well as of 4U1656-53 and 4U1820-30. Evidence was obtained for iron line emission from Cyg X-3

Joint observations of 4U1223-62 by the SAS-3 satellite and Columbia University proportional counter experiment on NASA rocket 26.054 UH

The pulsating X-ray binary 4U1223-62 and Vela X-1 were observed by Aerobee rocket-borne proportional counters. Valid X-ray events were telemetered and analyzed for possible flaring, quasiperiodic, and periodic pulsations, and for other nonstatistical behavior in the source. Both fast Fourier transform and autocorrelation programs were used. For several hours four days before and after the rocket flight, the SAS-3 satellite scanned the galactic plane in order to identify X-ray sources in the vicinity of 4U1223-62 and their intensities, and to provide positional accuracy of 0.25 for sources with intensity greater than 10% of the target. Observations of the source near the main peak of its pulsating period as defined by SAS-3 are discussed. There is no evidence of a spectral feature although twice as many photons were received as than from Vela X-1

A search for X-ray polarization in cosmic X-ray sources

Fifteen strong X-ray sources were observed by the X-ray polarimeters on board the OSO-8 satellite from 1975 to 1978. The final results of this search for X-ray polarization in cosmic sources are presented in the form of upper limits for the ten sources which are discussed elsewhere. These limits in all cases are consistent with a thermal origin for the X-ray emission

Implicating E. coli PAL in the pathogenesis of Gram-Negative sepsis

Just under half of all sepsis cases are caused by Gram-negative bacterial infections. Sepsis occurs when an infection results in a systemic inflammatory response, which can lead to organ dysfunction and death. Studies have shown that some outer membrane proteins, lipoproteins, and lipopolysaccharides are released from Gram-negative bacteria during sepsis; those proteins and LPS toxins are thought to induce the over-exuberant host inflammatory response, which is characteristic of sepsis. The ability to detect those proteins and determine the role they play in the development and severity of sepsis infection would be a powerful tool for immunotherapy. Escherichia coli (E. coli) are Gram-negative bacteria that release Lipopolysaccharide and several lipoproteins, including peptidoglycan-associated lipoprotein (Pal), which we propose is a bacterial mediator of Gram-negative sepsis. The goal of this study is to detect released Pal in human sera or urine of Gram-negative sepsis patients using purification and protein detection techniques in order to further implicate Pal in the pathogenesis of E. coli sepsis. Our findings suggest E. coli is capable of releasing Pal into both human sera and urine of patients with Gram-negative sepsis

Research investigation directed toward extending the useful range of the electromagnetic spectrum Progress report, 1 May - 31 Oct. 1966

Scientific research in atomic physics, solid state physics, and radio and X-ray astronom