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\title{PERIODS AND TYPES FOR SIX RED VARIABLES}

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Kaiser (1991, 1992) reported the photographic discovery of several new
variable stars and the rediscovery of several variables listed in the New Catalogue
of Suspected Variable Stars (Kholopov et al., 1982). I have examined these
stars on Harvard patrol plates of the Damon blue series (IIa-O) from 1973-1989.
This report presents the results for six DHK variables of late spectral type.
Except when noted, magnitudes of comparison stars were estimated with an image 
scale calibrated to photoelectric B magnitudes in nearby fields of the Guide
Star Photometric Catalogue (Lasker, Sturch et al., 1988). Equatorial coordinates 
and alternate identification in various catalogues can be found in the 71st and 
72nd Name Lists of Variable Stars, as cited.
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DHK\,18=TT Sextantis

Spectral type M4. Designated TT Sex in the 71st Name List (Kazarovets et al.,
1993). Observed on 202 plates, using a comparison star sequence extended
from the two comparison stars for BV\,715=RU Sex cited by Strohmeier et al.
(1965). Observed range 10.4-11.9 ptg. The light curve (Figure 1) gives a 
superficial impression of semiregular variations, but detailed plots of each
season's data show that no two cycles are similar. DFT analysis found only
a weak frequency peak near 700 days, but this period is expressed by only one
cycle on the light curve (centered at JD\,2446000). Altogether, these observations
suggest that variations are of the slow irregular type.
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DHK\,24=V1060 Tauri

Spectral type C4II. Designated V1060 Tau (Kazarovets et al., 1993). Observed
on 163 plates, range 10.3-11.8 ptg. The discovery report (Kaiser, 1992) gave
this variable an uncertain assigment to the slow irregular class (Lb:). DFT
analysis found a strong frequency peak at P=1163 days and a second, moderately
strong peak at P=527 days. Therefore, this star appears more likely to be SR
type with long and perhaps multiple periods.
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DHK=V704 Cassiopeiae

Spectral type M1. First noted by Espin (1894). Recently designated V704 Cas in the
72nd Name List (Kazarovets and Samus, 1995). Observed on 175 plates, range 
11.4-12.1 ptg. The light curve (Figure 1) shows distinct semiregular variations, 
with the amplitude of each cycle ranging from 0.2-0.7 magnitude. DFT analysis 
indicates a period of 379 days, which supersedes the estimate of 350: days in
the discovery report.
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DHK\,26=BP Canum Venaticorum

Spectral type K5. Observed on 139 plates. Recently designated BP CVn (Kazarovets
and Samus, 1995). Variability was first reported by Weber (1963), who found a
range of 11.4-12.1 ptg. I adopted his comparison sequence but found it 
necessary to add two fainter stars to accommodate my observed range of 11.9-12.8
ptg. The light curve (Figure 1) shows semiregular variations generally characterized 
by steep minima and broad maxima. DFT analysis found a strong frequency peak
at P=317 days, which supersedes the preliminary estimate of 300: days in the 
discovery report.

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DHK\,27=V517 Persei

Spectral type M8. Recently designated V517 Per (Kazarovets and Samus, 1995).
Observed on 113 Damon plates, using comparison star magnitudes interpolated
from the HU Per sequence of Meshkova (1940) less than 1 degree east of this new 
variable. Observed range 10.5-11.4 ptg. DFT analysis found a strong frequency 
peak at P=860 days, which is expressed by two prominent cycles on the light
curve (Figure 1). However, additional observations from 125 RH series plates,
1931-1952, show only a weak frequency peak at 1067 days and no sign of a period 
near 860 days. This star is probably a slow irregular variable with characteristic
cycles of 800-1100 days and minor variations of shorter durations.
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DHK\,28=LM Pegasi

Spectral type M2. Recently designated LM Peg (Kazarovets and Samus, 1995).
Observed on 166 plates, range 10.6-11.3 ptg. DFT period search found a weak
frequency peak equivalent to a period of 72 days, which supersedes the estimate
of 150: days in the discovery report. A light curve is not included here; a 
forthcoming report will present photoelectric photometry that supports the new period.
This star appears to be a typical small-amplitude, short period, red semiregular
variable.

Some of the information in this report was obtained from SIMBAD, database
of Strasbourg, France, Astronomical Data Center. I wish to thank Dr. Martha Hazen
for the opportunity to use the Harvard College Observatory plate collection for this
project.
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% Call for macros \authors - \authorsrightcol - \endauthors
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David B. WILLIAMS
9270-A Racquetball Way
Indianapolis, IN 46260 USA
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\references

Espin, T. E., 1894, {\it Astron. Nach.}, {\bf 135}, 265

Kaiser, D. H., 1991, {\it Inform. Bull. Var. Stars}, No.\,3677

Kaiser, D. H., 1992, {\it Inform. Bull. Var. Stars}, No.\,3814

Kazarovets, E. V., and Samus, N. N., 1995, {\it Inform. Bull. Var. Stars}, No.\,4140

Kazarovets, E. V., Samus, N. N., and Goranskij, V. P., 1993, {\it Inform. Bull. Var. Stars}, No.\,3840

Kholopov, P. N., editor, et al., 1982, New Catalogue of Suspected Variable Stars,
Moscow

Lasker, B., Sturch, C. et al., 1988, {\it Astrophys. Journ. Suppl.}, {\bf 68}, 1

Meshkova, T. S., 1940, {\it Perem. Zvezdy}, {\bf 5}, 255

Strohmeier, W., Knigge, R., and Ott, H., 1965, {\it Inform. Bull. Var. Stars}, No.\,115

Weber, R., 1963, {\it Inform. Bull. Var. Stars}, No.\,21

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