Zobrazeno 1 - 10
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pro vyhledávání: '"PERCY, JOHN R."'
Autor:
Percy, John R., Shenoy, Mayank H.
Publikováno v:
Volume 51 Number 2 (2023)
We briefly review the phenomenon of long secondary periods (LSPs) in red giants, and the LSP variable stars classification introduced in the All-Sky Automated Survey for Supernovae (ASAS-SN) variable star catalog; they are red giant Long Period Varia
Externí odkaz:
http://arxiv.org/abs/2312.05255
Autor:
Percy, John R.
Red giants are unstable to radial pulsation. About a third of them also show a long secondary period, 5 to 10 times the pulsation period. The long secondary periods were recently ascribed to eclipses of the red giant by a low-mass dust-enshrouded com
Externí odkaz:
http://arxiv.org/abs/2209.09144
Autor:
Percy, John R.1,2,3 john.percy@utoronto.ca
Publikováno v:
Journal of the Royal Astronomical Society of Canada. Oct2024, Vol. 118 Issue 5, p224-226. 3p.
Autor:
Percy, John R., Fenaux, Lucas
The All-Sky Automated Survey for Supernovae (ASAS-SN) has recently used over 2000 days of data to identify more than 50,000 variable stars, automatically classify these, determine periods and amplitudes for those that are periodic -- part of a remark
Externí odkaz:
http://arxiv.org/abs/1905.03279
Autor:
Percy, John R.
Photometry from the All-Sky Automated Survey for Supernovae (ASAS-SN), along with the AAVSO VSTAR time-series analysis package has been used to study the pulsational properties of 31 R Coronae Borealis (RCB) stars. Periods have been derived for many
Externí odkaz:
http://arxiv.org/abs/1903.05166
Autor:
Percy, John R. john.perchy@utoronto.ca
Publikováno v:
Journal of the Royal Astronomical Society of Canada. Apr2024, Vol. 118 Issue 2, p83-85. 3p.
Autor:
Percy, John R., Dembski, Kevin H.
We have measured the times of onset of recent fadings in four R CrB stars -- V854 Cen, RY Sgr, R CrB, and S Aps. These times continue to be locked to the stars' pulsation periods, though with some scatter. In RY Sgr, the onsets of fading tend to occu
Externí odkaz:
http://arxiv.org/abs/1809.04484
Autor:
Percy, John R., Qiu, Arthur Lei
We have used many decades of visual observations from the AAVSO International Database, and the AAVSO time-series analysis package VSTAR, to study the long-term changes in period, amplitude, and mean magnitude in about 30 normal pulsating red giants
Externí odkaz:
http://arxiv.org/abs/1805.11027