Analysis of Chromospheric Enhancement of Host Stars with Hot Jupiters in Elliptical Orbits
This study was carried out by a team of students, with me as the team leader. We started out with a literature survey. Inspired by the model proposed by A. F. Lanza, we relaxed the assumption of circular orbits to generalize the model to elliptical orbits. It was a great opportunity to work with SSERD, meet a team of Astro-enthusiasts, and work with them.
This study was carried out by a team of students, with me as the team leader. We started out with a literature survey. Inspired by the model proposed by A. F. Lanza, we relaxed the assumption of circular orbits to generalize the model to elliptical orbits. It was a great opportunity to work with SSERD, meet a team of Astro-enthusiasts, and work with them.
Recent observations of enhanced chromospheric activity on the surface of host stars with close-by giant planets suggest a possibility of magnetic interaction between the planetary magnetic field with the coronal field. The activity peak leads or lags the subplanetary point by a few degrees and, in extreme cases up to 170 degrees.
Recent observations of enhanced chromospheric activity on the surface of host stars with close-by giant planets suggest a possibility of magnetic interaction between the planetary magnetic field with the coronal field. The activity peak leads or lags the subplanetary point by a few degrees and, in extreme cases up to 170 degrees.
Our study investigates the analysis of stellar chromospheric activity enhancement of hosts stars due to close-by hot-jupiters or simply put chromospheric hotspots due to hot jupiters in elliptical orbits using the model by A.F. Lanza, developed back in 2008. We conducted a numerical analysis to study how the stellar activity peak with respect to the subplanetary point varies as a function of the radial star-planet distance for elliptical systems. The eccentricity of planetary orbit is introduced as a free parameter to the model while we also vary other parameters within the permissible limits to analyse their effect on the phase lag.
Our study investigates the analysis of stellar chromospheric activity enhancement of hosts stars due to close-by hot-jupiters or simply put chromospheric hotspots due to hot jupiters in elliptical orbits using the model by A.F. Lanza, developed back in 2008. We conducted a numerical analysis to study how the stellar activity peak with respect to the subplanetary point varies as a function of the radial star-planet distance for elliptical systems. The eccentricity of planetary orbit is introduced as a free parameter to the model while we also vary other parameters within the permissible limits to analyse their effect on the phase lag.
The magnitude of the phase lag decreased with the decrease in the star-planet distance as the planet moved closer to the star in the elliptical orbit scenario. Also, larger eccentricities caused a greater variation of the phase lag and so did a larger semi major axis. This extension is a more accurate version of Lanza(2008). We expect it to be a possible explanation to the observed on-off mechanism of chromospheric hotspots in some systems.
The magnitude of the phase lag decreased with the decrease in the star-planet distance as the planet moved closer to the star in the elliptical orbit scenario. Also, larger eccentricities caused a greater variation of the phase lag and so did a larger semi major axis. This extension is a more accurate version of Lanza(2008). We expect it to be a possible explanation to the observed on-off mechanism of chromospheric hotspots in some systems.
Internship Report
Internship Report
Use the link below or click on the image to access the report
Use the link below or click on the image to access the report