The settings of the second peakup has been changed to: ACQ/PEAK + G430L +0.1x0.03 + 4300 + exposure time = 0.1 second following the suggestion by our PC Paule Sonnentrucker. 747325683 ----- Attempting Submission 2 (Wed Mar 16 15:39:46 GMT 2016) ----- HST Phase II Proposal 14480 (hst-phase2.apt) successfully submitted. Receipt: # 14480-2 ----- Attempting Submission 3 (Thu Mar 17 21:22:44 GMT 2016) ----- Current massive-star astrophysics struggles with a number of urgent questions: what are the true mass-loss rates, what is the role of magnetic fields, how are X-rays produced? HD54879 provides an important laboratory to study these questions. While a strong magnetic field (2.1 ,kG) has been recently detected in this star, it otherwise exhibits a normal spectrum of O9.7 main sequence type. We propose joint XMM and HST observations of HD54879. Analysis of the UV spectrum will establish the parameters of the cool stellar wind, while from the XMM data the hot plasma component will be studied. The new observations will establish a gauge for stellar wind theory and provide a template X-ray spectrum for magnetic massive stars with weak wind. The immediate objective is to obtain the first UV spectrum of HD54879, using the HST STIS spectrograph. This will be the first UV spectrum of a non-peculiar late-type O dwarf with confirmed magnetic field. From these data, we want to infer the stellar wind parameters, especially the mass-loss rate and the wind velocity. The requested observations shall be performed with the E140M echelle grating centered at 1425Ang, and recorded by the FUV MAMA detector. The high spectral resolution is needed to separate the wind lines from the photospheric iron line forest. We aim at a S/N ratio of about 50 at the C IV doublet (~1500Ang). We uploaded the predicted model flux to the HST exposure time calculator (STIS.sp.639603), and obtained an exposure time of 42min. With the small 0.1'' x0.03'' aperture, the total count rate stays below the MAMA bright limit by a factor of two, which is safe since the source is not variable. HOT STARS 12 false false false false false false SUPPORTED STAR B0-B2 V-IV This object was generated by the targetselector and retrieved from the SIMBAD database. J2000 J2000 STIS/FUV-MAMA Spectroscopic No No E140M 1425 1458249245732 The scheduling data was generated by CASM 24.0. CASM was run in Phase II mode. /tmp/OPVisit5867444256827838280.xml (Tic-Visit :proposal-id 14480 :visit-id "01" :proposal-version -1 :trans-version "20160129" :date "17-Mar-2016 22:14:05.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "24" :si-bright-earth-limb-angle 20.0 :data-volume 227232 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 14480 :visit-id "01" :obset-id "01" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 14480 :visit-id "01" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2885 :al-overhead-at-end 0 :internal-dur-at-end 450 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3218 :pcs-gap 0 ) true 1 0