A new reddening for RR Tel from the HeII Paschen lines

Abstract

From the available STIS data of RR Tel, that have provided a coverage with absolutely calibrated data in a wide wavelength range, we have obtained a new determination of its reddening (E(B-V)=0.00) from the comparison of the observed HeII Paschen lines decrement relative to HeII lambda 4686 (for 24 HeII Paschen lines down to the region of the head of the series near lambda 2060 A) with the theoretical one as given in Storey and Hummer (1995) for case B, T=10,000 K and log Ne=6. This new E(B-V)=0.0 value has been confirmed from a re-analysis of the IUE low resolution data. We recall that the so far generally adopted value in the literature has been E(B-V)=0.10 as obtained by Penston et al. (1983).