\\ Species Tag:        &   14003 & Name:&  13CH             
\\ Version:            &       1 & & $^{13}$C-Methylidyne
\\ Date:       & April 2009       & & X $^2 \Pi$ states
\\ Contributor:&  B. J. Drouin & & 
\\             &  D. T. Halfen & & 
\\ Lines Listed:       &     628 & Q(300.0)=&      243.0012 
\\ Freq. (GHz) $<$     &    1651 & Q(225.0)=&      183.6926 
\\ Max. J:             &      16 & Q(150.0)=&      124.6073 
\\ LOGSTR0=            &   -12.0 & Q(75.00)=&       66.1069 
\\ LOGSTR1=            &   -12.0 & Q(37.50)=&       37.7869 
\\ Isotope Corr.:      &     0.  & Q(18.75)=&       24.4237 
\\ Egy. (cm$^{-1}$) $>$&     0.0 & Q(9.375)=&       17.9280 
\\ $\mu_a$ = & 1.46              & A=& 
\\ $\mu_b$ = &                   & B=& 422946.7
\\ $\mu_c$ = &                   & C=& 
\headend 
 
      The laboratory spectra of Halfen D.T., {\it et al.} Ap. J. 687(1), 731-736, 2008, were combined with the data
of McCarthy, M. C., Mohamed, S., Brown, J. M., and Thaddeus, P. 2006, Proc. Nat. Acad. Sci.,
103, 12263, in a fit to a Hund's case (b) Hamiltonian with fine and hyperfine structure parameters.
Additional hyperfine parameters improved the fit considerably and one rotational transition
was excluded in the catalog analysis (see archive).   The dipole moment for the main isotopomer
was taken from D. J. Phelps and F. W. Dalby, 1966, Phys. Rev. Lett. {\bf 16}, 3.