Stellar activity effects on high energy transits Joe Llama | - PowerPoint PPT Presentation

Stellar activity effects on high energy transits Joe Llama | joe.llama@lowell.edu | @joe_llama Evgenya Shkolnik Andrew Cameron Moira Jardine

Why observe high energy transits? Shallow 
 transit Deep 
 transit

Why observe high energy transits? Lower activity Higher activity

High energy transits of HD 189733b X-rays Poppenhaeger et al. (2013)

High energy transits of HD 189733b Lyman- ⍺ Bourrier et al. (2013)

The ultraviolet Sun Soft X-Ray Extreme UV 9.4 nm 21.1 nm 6.3 x 10 6 K 2.0 x 10 6 K Far UV Optical 170 nm 450 nm 5 x 10 3 K 5 x 10 3 K Llama & Shkolnik (2015) Data from SDO/AIA

Limb-brightened transits 13.1 nm (EUV) 450 nm (optical) Llama & Shkolnik (2015)

Limb-brightened transits 13.1 nm (EUV) 450 nm (optical) 1.00 1.00 Flux Flux 0.99 0.99 0.98 0.98 -0.02 0.00 0.02 -0.02 0.00 0.02 Phase Phase

Transiting the Sun I EUV FUV Soft X-Ray Optical 21.1 nm 170 nm 9.4 nm 450 nm 1.00 1.00 1.00 1.00 Flux 0.98 0.98 0.98 0.98 0.96 0.96 0.96 0.96 -0.02 0.00 0.02 -0.02 0.00 0.02 -0.02 0.00 0.02 -0.02 0.00 0.02 Phase Llama & Shkolnik (2015)

Transiting the Sun I 08 April 2014 14 April 2014 20 April 2014 26 April 2014 02 May 2014 1.00 1.00 1.00 1.00 Flux 0.98 0.98 0.98 0.98 0.96 0.96 0.96 0.96 -0.02 0 0.02 -0.02 0 0.02 -0.02 0 0.02 -0.02 0 0.02 -0.02 0 0.02 Phase Carrington rotation 2149 (April 2014) Llama & Shkolnik (2015)

Transiting the Sun I 1.0 Soft X-ray (9.4 nm) FUV (170 nm) Histogram Fraction 0.8 Optical (450 nm) Input Rp/R � = 0.1 0.6 0.4 0.2 0.0 0.05 0.1 0.15 Measured R p /R � Llama & Shkolnik (2015)

Transiting the Sun I 1.0 Soft X-ray (9.4 nm) FUV (170 nm) Histogram Fraction 0.8 Optical (450 nm) Input Rp/R � = 0.1 0.6 0.4 0.2 0.0 0.05 0.1 0.15 Measured R p /R � Llama & Shkolnik (2015)

Transiting the Sun II: Lyman- ⍺ Data from SDO/EVE Llama & Shkolnik (2016)

Transiting the Sun II: Lyman- ⍺ Llama & Shkolnik (2016)

Transiting the Sun II: Lyman- ⍺ Llama & Shkolnik (2016)

Transiting the Sun II: Lyman- ⍺ 0.10 Llama & Shkolnik (2016)

Transiting the Sun II: Lyman- ⍺ Llama & Shkolnik (2016)

Transiting the Sun II: Lyman- ⍺ Llama & Shkolnik (2016)

Summary • Stellar activity needs to be taken into account in the interpretation of these observations. • Simultaneous optical observations may help disentangle stellar activity signatures in high energy transits. • X-ray / UV transits are a great tool to investigate the upper atmospheres of exoplanets.