ORFEUS II echelle spectra: deuterium and molecular hydrogen in the ISM towards BD+39 3226

In ORFEUS II spectra of the sdO star ED +39 3226 interstellar hydrogen and deuterium is detected. From Ly alpha profile fitting and a curve of growth analysis of the Lyman series of HI and D I we derive the column densities N -H = 1.20(-0.22)(+0.28) . 10(20) cm(-2) and N-D = 1.45(-0.38)(+0.50) . 10(1 5) cm(-2). From the analysis of metal absorption lines in ORFEUS and IUE sp ectra we obtain column densities for 11 elements. In addition, we examine a bsorption lines of Hz for rotational excitation states up to J = 7. We find an H-2 ortho-to-para ratio of 2.5, the fractional abundance of molecular h ydrogen has a low value of log f = -4.08 for a total amount of N(H-2) = 4.8 (-1.6)(+2.0) . 10(15) cm(-2). The column densities of the excitation states reveal a moderate Boltzmann excitation temperature of 130 K and an equival ent excitation temperature for the excited upper stares due to UV pumping o f < 1800 K.