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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.
| Two-colour photometry for 9473 components of close Hipparcos double and multiple stars
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| The spectral classification of chromospherically active binary stars with composite spectra
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Osservazione e dati astrometrici
| Costellazione: | Orione |
| Ascensione retta: | 05h50m03.28s |
| Declinazione: | -05°53'53.4" |
| Magnitudine apparente: | 8.202 |
| Distanza: | 176.991 parsec |
| Moto proprio RA: | -4.2 |
| Moto proprio Dec: | -32.6 |
| B-T magnitude: | 9.452 |
| V-T magnitude: | 8.306 |
Cataloghi e designazioni:
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