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Helmken, H. F.

Publications and source records attributed to Helmken, H. F..

6 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1978

A search for centimetric wavelength emission from UV Ceti stars

Simultaneous radio and optical observations were obtained on three UV Cet flare stars: YZ CMi, AD Leo, and Wolf 424. The total simultaneous monitoring time was 33.9 hours during which time 41 optical flares were detected. Two enhancements were detected at 1420 MHz in close temporal association with optical flares, but are of uncertain validity. The results presented indicate that 1420 MHz emission during a typical stellar flare is less than 0.10 Jy.

Moffett, T. J.↗
NASA NTRS1973

Investigation of gamma rays from the galactic center

Data from Argentine balloon flights made to investigate gamma ray emission from the galactic center are summarized. Data are also summarized from a Palestine, Texas balloon flight to measure gamma rays from NP 0532 and Crab Nebulae.

Helmken, H. F.↗
NASA NTRS1973

Gamma-ray observations of the galactic centre.

Review of observation data obtained with a portable gas-Cerenkov gamma-ray telescope flown twice from Parana, Argentina (31.8 deg S), to search for gamma radiation from the galactic center. The angular resolution of this detector is not good enough to resolve the source structure controversy, i.e. whether the gamma radiation is coming from point sources or from a diffuse source along the galactic plane. Comparisons with observation data of other investigators are presented and discussed.

Helmken, H. F.↗