The magnetic field of ε Eri
Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
The magnetic eld of the star, ε Eri, is investigated. It is a nearbyK2V star. Previous studies have shown indications of a magnetic eld,but no measurements have been done with polarization. The Zeemaneect causes the lines in the spectrum to be split. The light also becomespolarized. By looking at the circular polarization, we can get informationabout the longitudinal magnetic eld.We study the polarization proles in the high-resolution spectra of εEri, to increase the S/N ratio, the LSD method is used. By combiningmany lines in the spectra, the shape of the averaged line can be derived.Using this approach, we obtain Stokes I, V, and the null spectra. Theyare then compared. From these, the mean longitudinal magnetic eld iscalculated. Data from two separate observing runs are compared: Onefrom 2010 and the other from 2011. Based on this analysis we nd a largereduction of magnetic eld strength of ε Eri in just one year.
Place, publisher, year, edition, pages
2013. , 22 p.
IdentifiersURN: urn:nbn:se:uu:diva-201519OAI: oai:DiVA.org:uu-201519DiVA: diva2:627839
Bachelor Programme in Physics
UppsokPhysics, Chemistry, Mathematics