Engineering Papers⌕ Search

Engineering topics

Budinger, T. F.

Publications and source records attributed to Budinger, T. F..

12 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1977

Apollo-Soyuz light-flash observations

While dark adapted, two Apollo-Soyuz astronauts saw eighty-two light flash events during a complete 51 deg orbit which passed near the north magnetic pole and through the South Atlantic Anomaly. The frequency of events at the polar parts of the orbit is 25 times that noted in equatorial latitudes and no increased frequency was noted in the South Atlantic Anomaly at the 225-km altitude. The expected flux of heavy particles at the northern and southern points is 1-2/min per eye, and the efficiency for seeing high Z-high energy (HZE) particles which were below the Cerenkov threshold is 50%.

Budinger, T. F.↗
NASA NTRS1976

Light flash observations during Apollo-Soyuz

A total of 82 visual events was reported by two dark-adapted astronauts during a 90-minute orbit at 225 km altitude. Silver chloride crystal events for that orbit totaled 69 stopping protons and alphas per sq cm and 304 heavy ions with stopping power of 150 MeV sq cm/g or greater. The frequency of visual observations near the geomagnetic poles corresponds to calculated abundances of ions with LET greater than 5 keV per micrometer in tissue. Nuclear collisions of fast protons on C, N, and O in the retina or the abundance of stopping protons can explain the low frequency of events in the SAA for this mission in comparison with the high frequency during Skylab IV at 443 km altitude.

Budinger, T. F.↗
NASA NTRS1976

Quantitative observation of light flash sensations experiment MA-106

Light flashes caused by the interaction of cosmic particles with the visual apparatus have been observed by astronauts on all space missions since Apollo 11. This Apollo Soyuz Test Project experiment compared measurements of the observer's visual sensitivity with measurements of the ambient radiation environment and with the frequency and character of the flashes observed. The data obtained reveal a latitude dependence of the frequency of observed flashes. This distribution of flashes is correlated with the distribution of cosmic particles with stopping power greater than 15 keV/ micrometers in the eye. The interaction of dark adaptation, specific ionization, and range of particles in the retina as factors in the visualization of particle passage is discussed.

Budinger, T. F.↗
NASA NTRS1975

Three-dimensional imaging of the myocardium with isotopes

Three methods of imaging the three-dimensional distribution of isotopes in the myocardium are discussed. Three-dimensional imaging was examined using multiple Anger-camera views. Longitudinal tomographic images with compensation for blurring were studied. Transverse-section reconstruction using coincidence detection of annihilation gammas from positron emitting isotopes was investigated.

Budinger, T. F.↗
NASA NTRS1972

Visual perception of accelerated nitrogen nuclei interacting with the human retina.

Visual phenomena have now been observed in high-energy nitrogen beams produced at the Berkeley Bevatron. Using a nitrogen beam deflected at about 266 MeV/nucleon, three scientifically trained subjects made a series of observations. These observations confirm earlier hypotheses and argue for electronic excitation in or near the outer segments as the important mechanism. A picture showing a simplified anatomy of the left eye in horizontal section is presented. Three regions where various beam positions intercepted visual nervous structures are indicated.

Budinger, T. F.↗
NASA NTRS1972

Visual phenomena induced by cosmic rays and accelerated particles

Experiments, conducted at cyclotrons together with observations by Apollo astronauts, suggest with little doubt that cosmic nuclei interacting with the visual apparatus cause the phenomenon of light flashes seen on translunar and transearth coast over the past four Apollo missions. Other experiments with high and low energy neutrons and a helium ion beam suggest that slow protons and helium ions with a stopping power greater than 10 to the 8th power eV/gram sq cm can cause the phenomenon in the dark adapted eye. It was demonstrated that charged particles induced by neutrons and helium ions can stimulate the visual apparatus. Some approaches to understanding the long term mission effects of galactic cosmic nuclei interacting with man and his nervous system are outlined.

Tobias, C. A.↗
NASA NTRS1972

Human visual response to nuclear particle exposures

Experiments with accelerated helium ions were performed in an effort to localize the site of initial radiation interactions in the eye that lead to light flash observations by astronauts during spaceflight. The character and efficiency of helium ion induction of visual sensations depended on the state of dark adaptation of the retina; also, the same events were seen with different efficiencies and details when particle flux density changed. It was concluded that fast particles cause interactions in the retina, particularly in the receptor layer, and thus give rise to the sensations of light flashes, streaks, and supernovae.

Tobias, C. A.↗
NASA NTRS1972

Observations of cosmic ray induced phosphenes

Phosphene observations by astronauts on flights near and far from earth atmosphere are discussed. It was concluded that phosphenes could be observed by the naked eye. Further investigation is proposed to determine realistic human tolerance levels for extended missions and to evaluate the need to provide special spacecraft shielding.

Chapman, P. K.↗
NASA NTRS1971

Light flash phenomenon seen by astronauts

The results from experiments conducted to characterize and elucidate light flashes seen by astronauts on Apollo 11, 12, 13, and 14 during transluna or transearth orbit are presented. The data show cosmic nuclei interacting with the visual apparatus causes the light flash phenomenon. The data also suggest that slow protons and helium ions with a stopping power greater than 10 KeV/micron will cause light flashes and streaks in the partially dark adapted eye. The effects of galactic cosmic nuclei interacting with man during long term missions are discussed.

Budinger, T. F.↗