Open AccessA frequency analysis of the p ‐mode pulsations of the Ap SrEu(Cr) star HD 119027
Author(s) -
Martinez Peter,
Koen C.,
Sullivan D. J.
Publication year - 1998
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1046/j.1365-8711.1998.01888.x
Subject(s) - physics , astrophysics , stars , star (game theory) , frequency analysis , magnetic field , asteroseismology , stellar pulsation , mode (computer interface) , astronomy , acoustics , computer science , operating system , quantum mechanics
We present new high‐speed, multisite photometric observations of the rapidly oscillating Ap star HD 119027 acquired over seven nights during 1996. A frequency analysis of these observations reveals the presence of oscillations at 1835, 1875, 1888, 1913, 1940, 1942 and (possibly) 1953 μHz. These frequencies are consistent with a spacing of either 13 or 26 μHz, depending on the reality of the oscillations at 1875 and 1953 μHz. The data in hand do not permit us to discriminate between the two possible spacings. If the smaller value of the spacing is correct, it suggests that HD 119027 is outside the main‐sequence band. Two of the frequencies listed above are separated by only 1.95 μHz, suggesting that they are modes of ( n ,ℓ) and ( n − 1, ℓ + 2), which in roAp stars is a quantity governed by the internal magnetic field.