1. Comparison of STAFF-SA and WBD Magnetic components of intense whistler-mode chorus Prepared by Ondrej Santolik 14th CAA Cross-Calibration meeting, York, 5-7 Oct 2011

2. 2 Context No comparisons between STAFF SA and WBD using magnetic component had ever been presented. An action was pending: CC8 – AI-45 STAFF :To carry out a cross-calibration study between STAFF-SA and WBD as they appears to be not in good agreement with WBD above 700 Hz while WBD/Whisper shows moderately good agreement. O. Santolik was in charge of this action, to be done during the summer.

3. 3 Power spectrogram of the electric field fluctuations. (WBD)‏ Power spectrogram of the magnetic field fluctuations. (STAFF-SA) Parallel component of the Poynting vector normalized by its standard deviation. (STAFF-SA)‏ Electromagnetic planarity. (STAFF-SA)‏ SOURCE // Bo \// Bo

4. 4 ZOOM on SOURCE REGION Selected intervals of WBD magnetic-filed measurements 08:44:55- 8:53:48, compared with the STAFF-SA onboard analyzed data WBD B Y component in the spinning spacecraft system (10s ~every 50s when Whisper is active) FFT of time series corresponding to STAFF-SA 4-s analysis intervals Power is averaged in frequency intervals of 27 STAFF-SA frequency channels STAFF-SA despun sunward component, analyzed onboard WBD

5. 5 WBD and STAFF-SA data in 56 time intervals of 4 s and 27 freq. steps

6. 6 STAFF-SA Band A But low power in band A

7. 7 STAFF-SA Band B

8. 8 STAFF-SA Band C Better, but intense waves Best

9. 9 ABC Noise Low wavesStrong waves

10. 10 Results Large differences of obtained PSD at low frequencies < 60 Hz, probably linked to the WBD high-pass filters. -> low signal, and no same sensitivity Median power ratio for f > 60 Hz is 1-5. STAFF-SA shows higher levels than WBD. (bands B & C) Large variations (~one order of magnitude) Very intense waves with PSD> 10 -7 nT 2 /Hz give similar values for STAFF-SA and WBD. Proper comparison is difficult, WBD samples one single spinning component, STAFF-SA gives onboard despun data.