Doppler Imaging of BD+22°4409 (LO Peg) Using Least Squares Deconvolution (CD-ROM Directory: contribs/lister)

We present maximum-entropy reconstructions of the rapidly rotating dwarf single star BD12284409 (LO Peg) from observations at the William Herschel Telescope in 1993 August. Since this star is too faint to use the conventional singleor three-line Doppler imaging methods, we make use of the novel method of least-squares deconvolution, which utilizes the large number of photospheric lines in an echelle spectrum to produce a single high signal-to-noise ratio profile. The star-spot distributions from the image reconstructions show cool features at both high and low latitudes, in contradiction to recent theoretical predictions of the dynamo behaviour in rapidly rotating stars. Cross-correlation of the images from consecutive nights shows a good correlation from the small-scale structures, but no evidence of surface differential rotation. From the cross-correlation of the high-latitude spot we are able to reject the period of 9.22 h of Jeffries et al. in favour of their preferred period of 10.17 h, confirming the result

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