VELOCITY STRUCTURE IN OPTICAL CH+ LINES TOWARD HD-190603 AND IMPLICATIONS FOR THE FORMATION OF CH+

In this paper, we report on observations of CH+ and other species accessible in optical wavelengths in the line of sight to HD 190603, a B1.5 lae supergiant. In this line of sight we see a shift in radial velocity between the CH+ line and other interstellar absorption lines such as CH and Ca I. The most likely explanation for this effect is the shock formation of CH+. We also make some estimates of likely preshock and postshock conditions which are consistent with the observations.