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\IBVShead{4367}{26 August 1996}       
        
\title{New Observations of Four  Galactic Cepheids}
                   
\begintext

      We have obtained CCD observations of a number of Cepheid variables which
have been mostly ignored, probably because they are unreachable with moderate
size telescopes and photoelectric equipment.  We have employed 14-bit CCD
systems to obtain results for several Cepheids which did not have photoelectric
light curves or had not been observed during the past 30 years or so.  
     
 We have chosen a series of comparison stars for differential observations
and we include here simple statistics on their variability.  Finder charts for the
fainter Cepheids are sometimes difficult to obtain and we have included CCD
finder charts of these Cepheids and comparison stars.  Our finder charts should
facilitate identification for future observations of these stars.

CCD observations were obtained with the Virginia Military Institute's 0.5\,m
DFM telescope, with a 14-bit Photometrics CCD system, and the U.S. Air Force
Academy's 0.4\,m DFM telescope, also with a 14-bit Photometrics CCD system.  V
and R filters were chosen to match the Johnson standard system with the CCD
spectral response (Bessell, 1990).  We obtained CCD images of a standard field in
M67 (Schild, 1983) and have obtained satisfactory transformations to the Johnson
system.  Our observations have been transformed to the Johnson V and R system. 
(We had problems with some of the early V observations because of a bad filter;
therefore, we have more R observations than V observations.)
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Figure 1.  CCD finder chart for CY Aur, V395 Cas, HZ Per and SX Per.  North is 
at top, east is at left.  The image size is approximately 5' on each side 
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\centerline{2}
\vskip 1mm
 All CCD images have been flat fielded, and all but a couple of images have
had bias and dark counts subtracted before flat fielding (no dark counts were
discernible on the USAFA images).  Exposures were standardized at four minutes
for the VMI images, and six minutes for the USAFA images.  Magnitudes were
obtained at VMI with DAOPHOT, and at USAFA by summing counts inside a square
aperture.


      CCD finder charts for each of the Cepheids discussed below are shown in
Figure 1.  For some of these stars, we were unable to unambiguously identify the variable until we had a few images centered on the variable's
coordinates, even using the Hubble Guide Star Catalog and GCVS positions.  The
R bandpass light curves are shown in Figures 2$-$5.  The field of view
of these finder charts (VMI images) is approximately 5 arcminutes; the original
scale is 30"/mm.  We found it difficult to compare our fields with some of the
original finder charts from 30 or 40 years ago, since those finder fields
(generally hand drawn or traced) often covered up to one degree and fainter
stars were not shown.  The effective bandpass was also generally different. 
     
 All stars on our images which were reasonably non-variable and bright
enough for good statistics were used to form an average for each field (2 to 4
stars), which was then used to obtain a differential magnitude with the variable
star.

      Our light curves have been graphed at an arbitrary epoch to place
maximum light at  phase 0.0.  The ephemeris used to calculate this phase is
shown in the caption of each graph, where the zero epoch corresponds to the new normal maximum to aid in checking long-term period changes,
or for comparison of peak light with other data.  The periods used to calculate
the phase in these graphs were obtained from the GCVS.  

{\bf CY Aur.}  The finder chart appears to agree with that given in the GCVS.  We
could not find any photoelectric photometry of this Cepheid as we began this
project, although we have now found observations from Berdnikov (1986) and
Schmidt et al. (1995).  A photographic light curve and the original finder chart are
given in Kurochkin (1951).  We graphed our R differential magnitudes in addition
to R magnitudes from Berdnikov (these data were obtained from the Welch
Cepheid database); see Figure 2.  We shifted our differential measures arbitrarily
(in magnitude) to correspond with his Johnson values.  We found good agreement
with his data, although some sections of the phase diagram are still inadequately
covered.

{\bf V395 Cas.}  This Cepheid shows an exceptionally well-behaved light curve,
especially in the R band.  Although our light curve is poorly covered just
before peak light, the rest of the curve is well defined.  The comparison stars
are also very stable.  Our finder chart agrees with the original chart.  We have
also graphed the R data from Berdnikov (1992; data from Welch database); our
differential data have been shifted by an arbitrary amount to coincide with
Berdnikov's data.  See Figure 3.

{\bf HZ Per.}  We located the original finder chart for HZ Per and there were no
problems in identifying this star.  We also graphed Berdnikov's (1993) data for
comparison.  The light curve is shown in Figure 4, and although the
comparison stars we used are well behaved with a standard deviation of 0\farcs 04 (in
V), the light curve of the Cepheid is noisy, particularly on rising light on the
red image.  

{\bf SX Per.}  We have some misgivings about agreement with the original finder chart
on this star, although there seems to be no doubt about having the correct star,
since the period agrees.  The light curve is shown in Figure 5.  A light curve
and finder chart are given by Kurochkin (1951); Henden (1980) also published 
photoelectric data for SX Per. 
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\begin{figure}[hpt]
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                \epsfbox{4367-f2.ps} 
                \end{center}
        \end{minipage}
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                \epsfxsize7.5cm \begin{center} \leavevmode
                \epsfbox{4367-f3.ps} 
                \end{center}
        \end{minipage}
\vspace{2ex}

\parbox[t]{7.5cm}{  Figure 2.  Light curve for CY Aur (R bandpass).  Initial 
epoch is ${\phi}_{0}$ = 2445643.0 (Julian day), and the GCVS period 
is 13\fd 85. Squares are our data, plus marks denote Berdnikov's observations
}
\hfill
\parbox[t]{7.5cm}{Figure 3.  Light curve for V395 Cas (R bandpass).  See Figure 2 for details. 
${\phi}_{0}$ = 2448099.0 and GCVS period is 4\fd 038
}
\end{figure}


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%\begin{center}
 % Figure 2.  Light curve for CY Aur (R bandpass).  Initial epoch is %${\phi}_{0}$ = 2445643.0 (Julian day), and the GCVS period is 13\fd 85. %Squares are our data, plus marks denote 
%Berdnikov's observations
%\end{center}
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%\centerline{\epsffile{4367-f3.ps}}
%\begin{center}
%Figure 3.  Light curve for V395 Cas (R bandpass).  See Figure 2 for details. 
%${\phi}_{0}$ = 2448099.0 and GCVS period is 4\fd 038
%\end{center}
\begin{figure}[hpt]
        \begin{minipage}{7.9cm}
                \epsfxsize7.5cm \begin{center} \leavevmode \hspace*{-5mm}
                \epsfbox{4367-f4.ps} 
                \end{center}
        \end{minipage}
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                \epsfxsize7.5cm \begin{center} \leavevmode
                \epsfbox{4367-f5.ps} 
                \end{center}
        \end{minipage}
\vspace{2ex}

\parbox[t]{7.5cm}{Figure 4.  Light curve for HZ Per (R bandpass).  See Figure 2 for details.  ${\phi}_{0}$ = 2448635.5 and GCVS period is 11\fd 28
}
\hfill
\parbox[t]{7.5cm}{Figure 5.  Light curve for SX Per (R bandpass). 
${\phi}_{0}$ = 2448646.0 and GCVS period is 4\fd 289967
}
\end{figure}


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%Figure 4.  Light curve for HZ Per (R bandpass).  See Figure 2 for details.  %${\phi}_{0}$ = 2448635.5 and GCVS period is 11\fd 28
%\end{center}

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%Figure 5.  Light curve for SX Per (R bandpass). 
%${\phi}_{0}$ = 2448646.0 and GCVS period is 4\fd 289967
%\end{center}
\vskip 1mm
\normalsize
\centerline{Table 1. Standard Deviations of Comparison Star Differences}
\large
\vskip 1mm
\begin{center}
\begin{tabular}{ccccccc}
\hline
        CY Aur   &               V395 Cas & & & & HZ Per&SX Per\\
    Stars \#1,3,4,5,7 & Stars \#1,2,6&  & & &Stars \#1,2,4,6,8&  Stars \#1,2,4\\
\hline
\\
\#1,3\ \ \ 0\fm 030& \#1,2\ \ \ 0\fm 006& & & &\#1,2\ \ \ 0\fm 029&\#1,2\ \ \ 0\fm048\\
\#1,4\ \ \ 0.029 &   \#1,6\ \ \   0.013& & & &\#1,4\ \ \   0.023& \#1,4\ \ \ 0.058\\
\#1,5\ \ \ 0.092 &   \#2,6\ \ \   0.009 & & & &\#1,6\ \ \   0.015& \#2,4\ \ \ 0.034\\
\#1,7\ \ \ 0.102 &                    & & & &\#1,8\ \ \   0.017& \\
\#3,4\ \ \ 0.019 &                    & & & &\#2,4\ \ \   0.044& \\
\#3,5\ \ \ 0.084 &                    & & & &\#2,8\ \ \   0.025& \\
\#3,7\ \ \ 0.095 &                    & & & &\#4,6\ \ \   0.021& \\
\#4,5\ \ \ 0.075 &                    & & & &\#4,8 \ \ \   0.031& \\
\#4,7\ \ \ 0.098 &                    & & & & \#6,8\ \ \    0.023& \\
\#5,7\ \ \ 0.124&                     & & & &           & \\
\hline
\end{tabular}
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\centerline{4}

\vskip 2mm

      We have included  a summary of our results with the comparison stars in
our 5' CCD fields.  In Table 1 is a listing of the standard deviations of our
magnitude differences of comparison stars which we used to obtain differential
magnitudes (R bandpass).  We used the comparison stars shown in Table 1 to
derive an average magnitude, which was then subtracted from the magnitude of
the Cepheid.  The V and R data have been deposited in the Welch Cepheid
database (http://www.physics.mcmaster.ca/Cepheid/). 
  
    We wish to acknowledge the support of our two institutions in encouraging
this research.  D.L.D. acknowledges a sabbatical award and several V.M.I. Summer
Research Grants in support of this work.  R.H.B. acknowledges generous telescope
time from the U.S. Air Force Academy.  We also wish to acknowledge a National
Science Foundation Research in Undergraduate Institutions grant (\#AST-861373),
which was used to purchase computer equipment for DAOPHOT data reduction,
with matching funds from V.M.I.  This research has made use of the SIMBAD
database operated at CDS, Strasbourg, France.
\vskip .7cm

\beginauthors
David L. DUPUY
Department of Physics and Astronomy
Virginia Military Institute
Lexington, VA 24450
dupuy@vmi.edu                                       %email
\authorsrightcol        
Raymond H. BLOOMER, Jr.
Department of Physics
King College
Bristol, TN 37620
rhbloome@king2.king.bristol.tn.us                                        %email

\vskip 3mm
\endauthors

\references

Berdnikov, L.N.,  1986, {\it Variable Stars}, {\bf 22}, 369

Berdnikov, L.N., 1992, {\it Astron. and Astrophys. Transactions}, {\bf 2}, 157

Berdnikov, L.N.,  1993, {\it Pis'ma Astron. J.}, {\bf 19}, 210

Bessell, M.S., 1990, {\it PASP}, {\bf 102}, 1181

Henden, A.A., 1980, {\it MNRAS}, {\bf 192}, 621

Kurochkin, N.E.,  1951, {\it Sov. Var. Stars} 7, No.\,{\bf 6}, 295

Schild, R., 1983, {\it PASP}, {\bf 95}, 1021

Schmidt, E.G., Chab, J.R., and Reiswig, D.E., 1995, {\it AJ}, {\bf 109}, 1239

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