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Analysis of MERCATOR data - Part II: variable A & F stars
For a few decades, a large international community is working at thedevelopment of stellar seismology, intending to open a new window on thestructure and evolution of stars, with the necessary paralleldevelopment of new observational techniques, modeling tools and methodsfor diagnostics and interpretation. This new window is associated withnew observables, characterizing the oscillations (frequencies,amplitudes, line profiles,...) which are sensitive to the stellarinterior and thus very complementary with surface observables,associated to astrometry, spectropolarimetry or interferometry.

New periodic variables from the Hipparcos epoch photometry
Two selection statistics are used to extract new candidate periodicvariables from the epoch photometry of the Hipparcos catalogue. Theprimary selection criterion is a signal-to-noise ratio. The dependenceof this statistic on the number of observations is calibrated usingabout 30000 randomly permuted Hipparcos data sets. A significance levelof 0.1 per cent is used to extract a first batch of candidate variables.The second criterion requires that the optimal frequency be unaffectedif the data are de-trended by low-order polynomials. We find 2675 newcandidate periodic variables, of which the majority (2082) are from theHipparcos`unsolved' variables. Potential problems with theinterpretation of the data (e.g. aliasing) are discussed.

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Dades d'Observació i Astrometria

Constel·lació:Ursa Major
Ascensió Recta:08h46m20.67s
Declinació:+50°01'22.5"
Magnitud Aparent:8.845
Distancia:244.499 parsecs
Moviment propi RA:-32.7
Moviment propi Dec:-28
B-T magnitude:9.184
V-T magnitude:8.873

Catàlegs i designacions:
Noms Propis   (Edit)
HD 1989HD 74504
TYCHO-2 2000TYC 3423-1859-1
USNO-A2.0USNO-A2 1350-07459915
HIPHIP 43062

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