... Arae

Based on observations made with the Very Large Telescope Interferometer at Paranal Observatory.

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... IDL

Package available at this address: http://www.mpia-hd.mpg.de/MIDISOFT/

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... monitor

This information has been extracted from the ESO Ambient conditions database of Paranal observatory: http://archive.eso.org/

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... IRAF

IRAF is distributed by the National Optical Astronomy Observatories, which is operated by the Association of Universities for Research in Astronomy (AURA), Inc., under cooperative agreement with the National Science Foundation.

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...=122 pc

This implies a luminosity $L_{\rm X}=1.02\times10^{29}$ erg s^-1, assuming the Hipparcos distance d=74 pc, which is still in the range of luminosities encountered for this spectral type by Cohen et al. (1998).

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... 1 mas

This correlated error is realistic since Narayanan & Gould (1999) report spatially correlated errors of Hipparcos up to 2 mas in the direction of the Pleiades and Hyades clusters.

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... reddening

We note also that their estimated distances for other Be stars like $\delta$ Cen seem also systematically overestimated compared to Hipparcos distances. On the contrary their estimated distance of alpha Eri is only 27 pc based on a wrong assumption of the radius of this star ( $R_{\rm eq}=R_{\rm pol}=4.1~R_\odot$) which is indeed very difficult to constrain without any interferometric observations.

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