PRIMORDIAL HELIUM ABUNDANCE BY RRL: NEW RESULT

Автор(и)

  • A. P. Tsivilev Pushchino Observatory of P.N. Lebedev Physical Institute, Pushchino Moscow reg., Russia, Russian Federation
  • R. L. Sorochenko Pushchino Observatory of P.N. Lebedev Physical Institute, Pushchino Moscow reg., Russia, Russian Federation
  • St. Cortiglioni Istitute IASF-CNR, Bologna, Italy, Italy
  • S. Poppi Istitute IRA-CNR, Bologna, Italy, Italy
  • St. Montebugnoli Istitute IRA-CNR, Bologna, Italy, Italy

DOI:

https://doi.org/10.18524/1810-4215.2004.17.93269

Ключові слова:

Cosmology, Helium abundance, Recombination Radio Lines - ISM.

Анотація

New results of the Primordial Helium abundance (Yp) measurement by radio recombination lines (RRL) observations from galactic HII regions are presented. The RRL observations were carried out with two Parabolas: RT32(λ = 13.5 mm and 3.5 cm, Medicina, Italy) and RT22 (λ = 8 and 13.5 mm, Pushchino, Russia). The current value was obtained on the base of five source observations with the accurate correction for both the ionization structure and dust influence. At present, the obtained Yp = 25.74(±1.0)value seems to be higher than that suggested by optical data, allowing the presence of unknown light particles, and is in agreement with the result from cosmic microwave background asymmetry.

Посилання

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Опубліковано

2017-03-15

Номер

Том 17 (2004)

Розділ

Статті

Ліцензія

Авторське право (c) 2017 Odessa Astronomical Publications

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Ця робота ліцензується відповідно до Creative Commons Attribution-NonCommercial 4.0 International License.

Відповідно Закону України про авторське право і суміжні права N 3792-XII від 23 грудня 1993 року