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TAP 26 was first reported by Feigelson et al. (1987) as a K7 PMS star.
Walter et al. (1988) found a relatively
high 
of about 70 km/s. It was first monitored
for rotational modulation by Bouvier et al. (1993). They reported a
2.5 day rotation period for this star which they
confirmed with their 1995 results (Bouvier et al. 1995).
While acknowledging that their derived equatorial velocity was only 28 km/s,
they suggested that they were seeing the orbital motion of a binary
system. Mathieu et al. (1989) observed this star, yet did not
report it as a spectroscopic binary. Prosser et al. (1995) were
suspicious that Bouvier et al. may have missed the
true period due to the fact that their sampling rate was not high enough.
Since Bouvier et al. only averaged one measurement per night, they were not
sensitive to periods of < 2 days.
Prosser et al. monitored TAP 26 during a six day period in which they
observed the star 12 times. They reported a 13 hour period. However,
they noted that the confidence in the period was low because they did
not obtain sufficient data.
TAP 26 was monitored from MTSB on 15 nights.
On average, five observations
were made of the star each night in each of three filters, V, R and I.
During three of these 15 nights, the filter wheel failed and
approximately 17 observations were made of the star, all in the I filter.
From these data, I derived a 0.715 day period for the star.
The MTSB data are displayed
in Figure 1. The MTSB data indicate that the previously
published period is an alias of the true, shorter, period. In
Figure 2, MTSB data are compared with those of Bouvier
et al. (1995). If one confines the period search range for the MTSB
data to be greater
than one day, the results are nearly identical to those for the data
presented by Bouvier et al. Further, the Prosser
et al. results are consistent with one of the aliases of our periodogram
result, as expected in the case of insufficient data. Combining the
period of TAP 26, with the published radius (1.1 R
; Walter et al. 1988)
one derives the sine of the inclination to Earth to be 
or about
68
.
