Interpretation of the BRITE oscillation data of the hybrid pulsator $\nu$ Eridani: a call for the modification of stellar opacities

Abstract

The analysis of the BRITE oscillation spectrum of the main sequence early B-type star $\nu$ Eridani is presented. Only models with the modified mean opacity profile can account for the observed frequency ranges as well as for the values of some individual frequencies. The number of the $\kappa$ modified seismic models is constrained by the nonadiabatic parameter $f$, which is very sensitive to the opacity changes in the subphotospheric layers where the pulsations are driven. We present an example of the model that satisfies all the above conditions. It seems that the OPLIB opacities are preferred over those from the OPAL and OP projects. Moreover, we discuss additional consequences of the opacity modification, namely, an enhancement of the efficiency of convection in the Z-bump as well as an occurrence of close radial modes which is a kind of avoided-crossing phenomenon common for nonradial modes in standard main sequence models.

10 pages, 5 figures, accepted for publication in MNRAS

References in corpus (8)

• A Grid of NLTE Line-Blanketed Model Atmospheres of Early B-type Stars
• Present-day cosmic abundances. A comprehensive study of nearby early B-type stars and implications for stellar and Galactic evolution and interstellar dust models
• The Stagger-grid: A grid of 3D stellar atmosphere models - III. The relation to mixing-length convection theory
• Abundance analysis of prime B-type targets for asteroseismology I. Nitrogen excess in slowly-rotating beta Cephei stars
• The two hybrid B-type pulsators: Nu Eridani and 12 Lacertae
• Convective envelopes in rotating OB stars
• Combining BRITE and ground-based photometry for the Beta Cephei star Nu Eridani: impact on photometric pulsation mode identification and detection of several g modes
• Comment on "Large enhancement in high-energy photoionization of Fe XVII and missing continuum plasma opacity"

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