Balloon is the brightest (B=11.8) pulsating sdB, has many frequencies, and its single dominant mode (P=356 seconds) has largest amplitude of all sdB stars

  We obtained 1600 spectra of 30 seconds exposure time, with the FIES spectrograph at the 2.6m Nordic Optical Telescope

  S/N<10  →  phase-folding  →  S/N∼50  →  combine 60 metal lines (X-cor)  →  S/N>200

  Posters on Balloon by Raquel Oreiro P38, and Roy Østensen P39