Combining SWAP and LYRA observations Matthieu Kretzschmar(1) (1) Royal Observatory of Belgium, matthieu@oma.com “Combining SWAP and LYRA observations”, M. Kretzschmar, SCSL, Bern 20 June 2006

SWAP and LYRA SWAP LYRA ? 3,11’’ 1mn ～10s 17.5 nm None ～20ms [0,20]nm Spatial resolution: Temporal resolution: - Nominal: - Optimal: … x 50 Time 0 mn 1 mn Spectral resolution: Wavelength “Combining SWAP and LYRA observations”, M. Kretzschmar, SCSL, Bern 20 June 2006

Spectral information 1 20 121 200 220 17 70 Wavelength Can we use the fact that the spectral overlapping between the 2 first LYRA channels corresponds roughly to the SWAP pass band ? Can we use the wide LYRA pass bands to model 17.5nm (DEM-like, statistical and/or empirical methods) ? Wide Lyra pass bands. 2 of them are optically thick. “Combining SWAP and LYRA observations”, M. Kretzschmar, SCSL, Bern 20 June 2006

Plasma temperature seen by SWAP and LYRA Spectral coverage is so different that it can be useful to think in term of temperature. These are the emissivity curves corresponding to the pass bands assuming thermal equilibrium. “Combining SWAP and LYRA observations”, M. Kretzschmar, SCSL, Bern 20 June 2006

Plasma temperature seen by SWAP and LYRA Aluminium: Transition region + Corona. Zirconium: Corona (cold - 106- and ‘hot’ -107K- one) SWAP: Corona (mainly the cold one. Zirconium Aluminium SWAP 104 105 106 107 108 “Combining SWAP and LYRA observations”, M. Kretzschmar, SCSL, Bern 20 June 2006

Spectral information Preliminary conclusions: it is a hard task to combine mathematically the LYRA and SWAP pass bands. However, 2 channels of LYRA (Al and Zr) include the SWAP pass band. Furthermore, Zr and SWAP observe radiation coming from nearly the same plasma. “Combining SWAP and LYRA observations”, M. Kretzschmar, SCSL, Bern 20 June 2006

Using SWAP to identify the spatial features that make the irradiance varying Mid-term variation On a mid time scale basis, one can track AR, QS, CH, and check the EUV irradiance model. (NRLEUV -Warren et al., 1001-, Kretzschmar et al. 2004) If this works, on can model the whole irradiance spectral variation. “Combining SWAP and LYRA observations”, M. Kretzschmar, SCSL, Bern 20 June 2006

Small-term variations (I) Using SWAP to identify the spatial features that make the irradiance varying Small-term variations (I) This is a new field from which one can learn much. The 4 Lyra pass bands will inform us about the temporal evolution of the solar feature in different part of the solar atmosphere. SEM:0-50 nm “Combining SWAP and LYRA observations”, M. Kretzschmar, SCSL, Bern 20 June 2006

Using SWAP to identify … Small-term variations (II) ? ? “Combining SWAP and LYRA observations”, M. Kretzschmar, SCSL, Bern 20 June 2006

Using SWAP to identify … Small-term variations (II) Movie… Can we observed small brightnings, EIT wave, .. (others?) counterparts in irradiance measurements ? “Combining SWAP and LYRA observations”, M. Kretzschmar, SCSL, Bern 20 June 2006

Using SWAP to identify … Small-term variations (II) I(xi,j,t) -with i,j pixel address- to be compared mathematically with irradiance variation: SVD or PCA analysis gives the orthogonal normalized temporal variation that maximize the signal variance. “Combining SWAP and LYRA observations”, M. Kretzschmar, SCSL, Bern 20 June 2006

Temporal evolution Supposing roughly that the SWAP and (one) LYRA pass band are emitted by the same plasma, one should expect similar normalized variation for Lyra irradiance and SWAP integrated count rates. EIT calibration (or probably my error in processing EIT data) ? SWAP calibration (or …) ? This is essential if one wish to study the relative variations. Can we use LYRA to improve the calibration (and staibility of SWAP) “Combining SWAP and LYRA observations”, M. Kretzschmar, SCSL, Bern 20 June 2006

Using SWAP for the aeronomy studies of LYRA PROBA II will have some ‘eclipse periods’ and thus will see the sun thought the Earth’s atmosphere. This will allow LYRA to measure the attenuation of the solar flux from which one can derive atmospheric property (density). LYRA measurements To the Sun Apparent Sun diamater: 25 km “Combining SWAP and LYRA observations”, M. Kretzschmar, SCSL, Bern 20 June 2006

Using SWAP for the aeronomy studies of LYRA SWAP will tell how much the Sun has changed from non-occultation LYRA measurements. How many measurements are made by LYRA during the PROBA path for these 25 km and what can we learn for that ? V(proba2)=.. (Marie?) LYRA measurements To the Sun Apparent Sun diamater: 25 km “Combining SWAP and LYRA observations”, M. Kretzschmar, SCSL, Bern 20 June 2006

Something I forgot to discuss Can LYRA be used to interpolate in some senses LYRA images ? “Combining SWAP and LYRA observations”, M. Kretzschmar, SCSL, Bern 20 June 2006