Seismic detection of boundaries of stellar convective regions

• Type: Article in International Scientific Journal
• Date: 1998

Authors

Monteiro, MJPFG (Author) FCUP; Christensen Dalsgaard, J (Author) Other; Thompson, MJ (Author) Other

Journal

The Journal is awaiting validation by the Administrative Services.

Title: NEW EYES TO SEE INSIDE THE SUN AND STARS: PUSHING THE LIMITS OF HELIO- AND ASTEROSEISMOLOGY WITH NEW OBSERVATIONS FROM THE GROUND AND FROM SPACE

Vol. 371

Pages: 315-316

Indexing

ISI Web of Knowledge - 6 Citations

Scientific classification

FOS: Natural sciences > Physical sciences

Other information

Authenticus ID: P-001-9J3

DOI: 10.1017/s0074180900238850

Abstract (EN): <jats:p>The edge of a convective region inside a star gives rise to a characteristic periodic signal in the frequencies of its global p-modes (e.g. [1], [4]), such that the frequencies ¿ are then essentially a smooth function of the mode order <jats:italic>n</jats:italic> plus a periodic component <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" mime-subtype="gif" xlink:type="simple" xlink:href="S0074180900238850_inline1" />. Here the amplitude is <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" mime-subtype="gif" xlink:type="simple" xlink:href="S0074180900238850_inline2" />, with <jats:italic>A</jats:italic><jats:sub>1</jats:sub> and <jats:italic>A</jats:italic><jats:sub>2</jats:sub> being values that depend weakly on frequency ¿: <jats:italic>A</jats:italic><jats:sub>1</jats:sub> is always present in general, but <jats:italic>A</jats:italic><jats:sub>2</jats:sub> will be non-zero only if there is overshoot; <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" mime-subtype="gif" xlink:type="simple" xlink:href="S0074180900238850_inline3" /> is essentially the acoustical depth ¿ (i.e. the sound travel time) of the edge of the convection zone measured from the surface of the star; and ¿<jats:sub>0</jats:sub> is a constant related to the phase of the eigenfunctions. To facilitate the comparison between different stars, we consider the amplitude evaluated at a fiducial frequency by defining <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" mime-subtype="gif" xlink:type="simple" xlink:href="S0074180900238850_inline4" />. For the Sun, we chose as the reference frequency <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" mime-subtype="gif" xlink:type="simple" xlink:href="S0074180900238850_inline5" />. If we take this value and scale it for other stars (using just a standard homology scaling for frequencies), we find <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" mime-subtype="gif" xlink:type="simple" xlink:href="S0074180900238850_inline6" />.</jats:p>

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 2