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Patrick Boumier (to Alan). Building GOLF. IAS + OCA + SAp + Bordeaux Obs. + IAC + UCLA. Caution Any resemblance to persons living or dead or to scenarii is not purely accidental, but the details were somewhat different… !.
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Patrick Boumier (to Alan) Building GOLF Alan day
Caution Any resemblance to persons living or dead or to scenarii is not purely accidental, but the details were somewhat different… ! Alan day
Parallels are drawn between the asymmetric resonance profiles observed in global helioseismology and the Fano theory for autoionisation profiles in atomic spectroscopy. . Alan day
Resonance profiles in Helioseismology (HS) SoHO/MDI Alan day
Autoionisation profiles in atomic spectroscopy (AS) Fano's expression (Connerade, 1998): Rydberg series Alan day
As invisible as Obelixisalwayshungry, the two expressions have an identicalform ! - Fano HS, if we suppress the term B2 and the non-correlated background, the asymmetry factor q being equivalent to 1/B. - The asymmetry sign reversal comes naturally from how the system is observed (atomic physics). Alan day
Why did Alan think of a parallel between HS and AS ? • Becausehewas not happy with the HS profile formula ! - Intoduction of a “correlated background” to explain the sign reversal for B depending on the observable. - Derivedthrough an expansion in small quantities and the neglect of higher order terms. • valid only in the immediate vicinity of the resonance. - To which physics the B2 term does correspond ? i Alan day
Is there physics behind the formal parallel ? Both situations can be thought of as arising through the mixture of coincident stationary states, one arising from a discrete resonance, the other a “continuum" in the AS language, which is equivalent to “background noise" in the present-day terminology of HS. We show that the underlying physics of the interaction of a discrete resonance with a correlated continuum is common to both systems. Alan day
What can we conclude for Helioseismology ? - The additional term B2 in the HS fitting formula is unnecessary AND • The formula is fundamentally valid on the whole frequency rangeand can be used to fit all modes to gether AS • Thanks to the AS situation we can predict which resonances will interact with which continua and with which other resonances ! Alan day
Even more interesting as far as Physics is concerned: This works addresses the question whether the two interacting influences of excitation sources and correlated solar background, are really separate independent processes. Alan day
Does this work comes from perseverance or from obstinacy ? • Is Alan an artist ? The art of making people believeheisperseveringwhileheisobstinate/stubborn… (L’art de faire croire à de la persévérance alors qu’il est complètement obstiné/obsédé). Probably a subtlemixing ! • Obstinacy + perseverance obstiverance • Obstination + persévérance obstivérance Alan day
Know what ? Some students gave a nickname to Alan: Idefix (idée fixe) ! English translation: Dogmatix… ! Idée fixe obstiverance ≠ dogmatism Alan day
Building GOLF a relation with Gabriel ÔLovely Fellow Thank you Alan ! Alan day