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\begin{document}
\IBVShead{4596}{3 June 1998}

\IBVStitle{HD\,62454 -- A New Spectroscopic Binary}


\IBVSauth{A.\ B.~KAYE}

\IBVSinsto{Georgia State University Department of Physics and Astronomy; 
38 Peachtree Center Avenue, Suite 1039A; 
Atlanta, Georgia  USA  30303-3083}
\IBVSinsto{e-mail: kaye@chara.gsu.edu}

\SIMBADobj{HD62454}
\IBVStyp{ F0 }
\IBVSkey{spectroscopic binaries}

\begintext

HD 62454 is a new addition to the ``Master List'' of $\gamma$ Doradus--type 
Variables (Handler \&  
Krisciunas 1997).  This star was first recognized by Henry (1996) 
as a low--amplitude variable after it was chosen as a comparison star 
for high--precision photometry of solar--type stars with the 
SAO / TSU 0.75 m automatic photoelectric telescope (Henry 1995) 
and preliminary data were presented by Kaye et al.\ (1998).  

Thirty-three high signal-to-noise ratio spectra were obtained over eleven  
nights at the Kitt Peak National Observatory during late November 
and early December of 1997.  These spectra were taken simultaneously 
with photometry obtained at both Washington Camp, Arizona and 
Sierra Nevada, Spain (Kaye 1998).  The signal-to-noise ratio (SNR) 
is estimated to be approximately 275.  Each spectrum covers the wavelength region 
4403 to 4617 \AA ngstr\"{o}ms and were obtained using grating A, camera 5, and the long 
collimator.  Filter 4-96 was used to block both higher and lower orders.  Data were 
recorded on the F3KB CCD ($3000 \times 1000$ pixels, $15 \times 15$ $\mu$m pixel 
size, 75\% detector quantum efficiency 
(DQE) at 4210 \AA ngstr\"{o}ms); these spectra have a reciprocal dispersion of 0.070 
\AA ngstr\"{o}ms per pixel (4.643 \AA ngstr\"{o}ms per millimeter), resulting in a resolving power of 
approximately 34,400.  The slit width was fixed at 250 $\mu$m, which corresponds to 1.81 seconds of arc.  The 
projected slit image was 0.027 mm and covered 1.77 pixels. 

Subsequent analysis based on the the time series of first moments 
of the Fe II $\lambda$ 4508.289 
photospheric line indicates that HD 62454 is a spectroscopic binary.  Table 1 lists 
the measured radial velocities (plotted in Figure 1), and Table 2 presents the 
preliminary orbital elements of the system.  The standard deviation of the orbital fit 
(noted as $\sigma$ in Table 2) is higher than expected due to the ongoing pulsations 
present in HD 62454a.

A complete photometric analysis and a preliminary spectroscopic analysis 
(using the method of moments as related to the ``$\gamma$ Doradus phenomenon'') 
are presented in Kaye (1998).  



\newpage

\centerline{Table 1.  Radial Velocities of HD 62454a}
\vskip 3mm
\begin{center}
\begin{tabular}{cr}
\hline
HJD$-2450700$  &   $V_{r}$\ \ \ \ \\
\hline
       77.9570  & 54.4103   \\
       77.9784  & 54.8054   \\
       78.8511 &  52.0470    \\
       78.8726  & 51.1388    \\
       78.9613  & 49.9706   \\
       78.9827  & 49.7631    \\
       80.7640  & 29.3740    \\
       80.7852  & 28.9516    \\
       80.8063  & 29.0373   \\
       80.8790  & 27.6276  \\
       80.9002  & 27.2981    \\
       80.9214  & 26.9832   \\
       81.7426  & 11.2322   \\
       81.7903  & 10.0462    \\
       81.8850   & 8.6168    \\
       81.9515  &  7.6767   \\
       81.9982 &   6.6965   \\
       82.7728  & $-$6.4372  \\ 
       82.9963  & $-$9.5304  \\
       85.8779 & $-$42.5398  \\
       85.8990  & $-$42.0260   \\
       85.9202  & $-$41.9840   \\
       86.0076  & $-$41.8618  \\
       86.0287  & $-$42.1527  \\
       86.8909  & $-$23.2998 \\
       86.9121  & $-$22.8126  \\
       86.9783  & $-$22.4151  \\
       87.0341  & $-$20.0233  \\
       87.7519  &  9.1827   \\
       87.8523  & 15.0026   \\
       87.8734  & 16.0439   \\
       87.9550   & 20.2169  \\
       87.9762   & 20.6628   \\
\hline
\end{tabular}
\end{center}



\vskip 5mm
\centerline{Table 2.  Preliminary Orbital Elements of HD 62454a}
\vskip 3mm
\begin{center}
\begin{tabular}{cc}
\hline
Orbital Element &   Value   \\
\hline
$\gamma$ & 10.87 $\pm$ 0.10 km s$^{-1}$\\
$K_{1}$ & 50.79 $\pm$ 0.17  km s$^{-1}$\\
$e$ & 0.166 $\pm$ 0.002 \\
$\Omega$ & 179\fdeg 45 $\pm$ 0\fdeg 011 \\
$T_{0} - 2450700$ & 70.87 $\pm$ 0.04 \\
$P$ & 14.02 $\pm$ 0.02 days\\
mass function & 0.183 $\pm$ 0.002 \\
$\sigma$ & 5.62  km s$^{-1}$\\
\hline
\end{tabular}
\end{center}

\vskip 1cm
\IBVSfig{10cm}{4596-f1.ps}{A radial velocity curve of the primary star (HD\,62454a) 
based on the first moments of the Fe~II $\lambda$ 4508.289 line}
\vskip 1cm

I thank Dr.\ W.G.\ Bagnuolo and Dr.\ D.R.\ Gies for useful conversations.  
In addition,  thanks are due to the administration and the staff of KPNO for 
the telescope time and for assistance during the observations and the data reduction 
process. 

\vskip 2mm

\references


Handler, G. \& Krisciunas, K.,  1997, {\it Delta Scuti Star Newsletter}, {\bf 11}, 3

Henry, G.W., 1995, {\it ASP Conf. Ser.}, {\bf 79}, 44,
{\it Robotic Telescopes:  Current Capabilities,
Present Developments and Future Prospects for Automated Astronomy},
eds. G.W.\ Henry and J.A.\ Eaton
%Changed: Thu Jun  2 16:15:37 MEST 2005

Henry, G.W., 1996  Private Communication

Kaye, A.B., 1998, Ph.D. Dissertation, Georgia State University

Kaye, A.B., Bagnuolo, W.G., Hall, D.S., \& Henry, G.W.,  1998, 
{\it ASP Conf. Ser.}, {\bf 135}, 497,
{\it A Half Century of Stellar Pulsation Interpretations}, eds. P.A.\ Bradley
\& J.A.\ Guzik
%Changed: Thu Jun  2 16:15:37 MEST 2005

\endreferences

\newpage

\centerline{\bf ERRATUM}
\vskip 2cm

When checking the data published in the IBVS No.\,4543 issue
for updating and supplementing the variable star catalogs,
several incorrect and confusing statements have been found. 

The last sentence of the first paragraph should read as follows:

Object 4 is NGC 13386 (Wisniewski and Coyne, 1976, hereafter WC)
and object 13 is NSV 13792 (Geyer and Gieseking, 1975, hereafter
GG).

In Table 1, Note 2 should be in the SAME line with Note 1 (both belong
to NSV 13792).

On page 2, the contents of Note 5 and Note 2 are interchanged.
\vskip 1.5cm

\noindent
G.I. MEDVEDEVA and N.N. SAMUS\\
Institute of Astronomy\\
Russian Academy of Sciences\\
Pyatnitskaya 48\\
109017 Moscow\\
Russia\\
e-mail: samus@sai.msu.su\\


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