Abstract
In the course of a search for solar-like oscillations in bright late-type stars, we have observed Doppler variability in the F5 subgiant Procyon. The variations have frequencies within a 1.1 mHz range centered at 0.9 mHz, and a total rms amplitude within that range of 2.5 m s-1. Observations of Arcturus and scattered sunlight made with the same equipment during the same time interval show no such variation, indicating that the variations seen on Procyon are of stellar origin. The Doppler signal seen is entirely consistent with solar-like p-modes on Procyon, with maximum mode amplitudes of about 50 cm s-1 and periods around 20 minutes. Several statistical tests support the identification of the signal with narrow-band oscillations, but none does so conclusively. Assuming that the signal does arise from p-modes, there is evidence that the frequency splitting v0 is 71 μHz. We emphasize, however, that the data do not permit a definitive estimate of this quantity, and other values of v0 fit the observations about equally well. In order to clarify the sources of ambiguity in this and similar observations, we describe in detail the data acquisition, reduction, and interpretation.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 599-609 |
| Number of pages | 11 |
| Journal | Astrophysical Journal |
| Volume | 368 |
| Issue number | 2 |
| DOIs | |
| State | Published - Feb 20 1991 |
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All Science Journal Classification (ASJC) codes
- Astronomy and Astrophysics
- Space and Planetary Science
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Detection of possible p-mode oscillations on procyon. / Brown, Timothy M.; Gilliland, Ronald L.; Noyes, Robert W.; Ramsey, Lawrence W.
In: Astrophysical Journal, Vol. 368, No. 2, 20.02.1991, p. 599-609.Research output: Contribution to journal › Article
TY - JOUR
T1 - Detection of possible p-mode oscillations on procyon
AU - Brown, Timothy M.
AU - Gilliland, Ronald L.
AU - Noyes, Robert W.
AU - Ramsey, Lawrence W.
PY - 1991/2/20
Y1 - 1991/2/20
N2 - In the course of a search for solar-like oscillations in bright late-type stars, we have observed Doppler variability in the F5 subgiant Procyon. The variations have frequencies within a 1.1 mHz range centered at 0.9 mHz, and a total rms amplitude within that range of 2.5 m s-1. Observations of Arcturus and scattered sunlight made with the same equipment during the same time interval show no such variation, indicating that the variations seen on Procyon are of stellar origin. The Doppler signal seen is entirely consistent with solar-like p-modes on Procyon, with maximum mode amplitudes of about 50 cm s-1 and periods around 20 minutes. Several statistical tests support the identification of the signal with narrow-band oscillations, but none does so conclusively. Assuming that the signal does arise from p-modes, there is evidence that the frequency splitting v0 is 71 μHz. We emphasize, however, that the data do not permit a definitive estimate of this quantity, and other values of v0 fit the observations about equally well. In order to clarify the sources of ambiguity in this and similar observations, we describe in detail the data acquisition, reduction, and interpretation.
AB - In the course of a search for solar-like oscillations in bright late-type stars, we have observed Doppler variability in the F5 subgiant Procyon. The variations have frequencies within a 1.1 mHz range centered at 0.9 mHz, and a total rms amplitude within that range of 2.5 m s-1. Observations of Arcturus and scattered sunlight made with the same equipment during the same time interval show no such variation, indicating that the variations seen on Procyon are of stellar origin. The Doppler signal seen is entirely consistent with solar-like p-modes on Procyon, with maximum mode amplitudes of about 50 cm s-1 and periods around 20 minutes. Several statistical tests support the identification of the signal with narrow-band oscillations, but none does so conclusively. Assuming that the signal does arise from p-modes, there is evidence that the frequency splitting v0 is 71 μHz. We emphasize, however, that the data do not permit a definitive estimate of this quantity, and other values of v0 fit the observations about equally well. In order to clarify the sources of ambiguity in this and similar observations, we describe in detail the data acquisition, reduction, and interpretation.
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UR - http://www.scopus.com/inward/citedby.url?scp=0001295812&partnerID=8YFLogxK
U2 - 10.1086/169725
DO - 10.1086/169725
M3 - Article
AN - SCOPUS:0001295812
VL - 368
SP - 599
EP - 609
JO - Astrophysical Journal
JF - Astrophysical Journal
SN - 0004-637X
IS - 2
ER -