Aims.We discuss a simple model of a line-tied coronal arcade with piecewise constant density to explore the effects of curvature on radially polarised fast modes.Methods.A partial differential equation is derived for the velocity perturbation of the fast modes and it is solved analytically in terms of Bessel functions of half integer order

Equations (1) and (2) were set incorrectly in the published version of this paper; the equivalence appearing in the denominator should in fact be the final value on the right-hand side. The correct forms of these equations are:AKs=(EH-K)/((λH/λKs)-1.53-1)=1.55-0.21/((1.662/2.159)-1.53-1)=2.73, (1)andAKs=(EJ-K)/((λJ/λKs)-1.53-1)=4.62-0.89/((1.2352

Not Available

Aims.We report the discovery of five new dwarf novae that were spectroscopically identified in the Hamburg Quasar Survey (HQS), and discuss the properties of the sample of new dwarf novae from the HQS.Methods.Follow-up time-resolved spectroscopy and photometry have been obtained to characterise the new systems.Results.The orbital periods determined

In ATEL #871 the fluxes were incorrectly quoted. All the fluxes should be multiplied by 1E-10 in order to obtain the correct values. The quoted luminosities are correct since the right fluxes were used to calculate them. We apologize for any confusion this error might have caused.

IAUC 8737 available at Central Bureau for Astronomical Telegrams.