High sensitivity of p-modes near the acoustic cutoff frequency to solar model parameters

Journal Article · Fri Mar 01 04:00:00 EST 1991 · Astrophysical Journal; (USA)

DOI:https://doi.org/10.1086/169755· OSTI ID:5701930

Guenther, D B ^[1]

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1. Yale Univ., New Haven, CT (USA)

The p-mode frequencies of low l have been calculated for solar models with initial helium mass fraction varying from Y = 0.2753-0.2875. The differences in frequency of the p-modes in the frequency range, 2500-4500 microHz, do not exceed 1-5 microHz among the models. But in the vicinity of the acoustic cutoff frequency, near 5000 microHz the p-mode frequency differences are enhanced by a factor of 4. The enhanced sensitivity of p-modes near the acoustic cutoff frequency was further tested by calculating and comparing p-mode frequencies of low l for two solar models one incorporating the Eddington T-tau relation and the other the Krishna Swamy T-tau relation. Again, it is found that p-modes with frequencies near the acoustic cutoff frequency show a significant increase in sensitivity to the different T-tau relations, compared to lower frequency p-modes. It is noted that frequencies above the acoustic cutoff frequency are complex, hence, cannot be modeled by the adiabatic pulsation code (assumes real eigenfrequencies) used in these calculations. 20 refs.

• OSTI ID: 5701930
• Journal Information: Astrophysical Journal; (USA), Journal Name: Astrophysical Journal; (USA) Vol. 369; ISSN ASJOA; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

640104* -- Astrophysics & Cosmology-- Solar Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ABUNDANCE
ADIABATIC PROCESSES
ATMOSPHERES
COMPARATIVE EVALUATIONS
ELECTROMAGNETIC RADIATION
ELEMENT ABUNDANCE
ELEMENTS
FLUIDS
GASES
HELIUM
MAIN SEQUENCE STARS
MATHEMATICAL MODELS
NONMETALS
OSCILLATIONS
RADIATIONS
RARE GASES
SEISMIC P WAVES
SEISMIC WAVES
SEISMOLOGY
SOLAR ATMOSPHERE
STAR MODELS
STARS
SUN
VISIBLE RADIATION