Bihelical spectrum of solar magnetic helicity and its evolution

Singh, Nishant K.; Käpylä, Maarit J.; Brandenburg, Axel; Käpylä, Petri J.; Lagg, Andreas; Virtanen, Ilpo (2018-08-22)
 
Avaa tiedosto
Lataukset: 

URL:
https://doi.org/10.3847/1538-4357/aad0f2

Singh, Nishant K.
Käpylä, Maarit J.
Brandenburg, Axel
Käpylä, Petri J.
Lagg, Andreas
Virtanen, Ilpo
IOP Publishing
22.08.2018

Singh, N., Käpylä, M., Brandenburg, A., Käpylä, P., Lagg, A., Virtanen, I. (2018) Bihelical Spectrum of Solar Magnetic Helicity and Its Evolution. Astrophysical Journal, 863 (2), 182. doi:10.3847/1538-4357/aad0f2

https://rightsstatements.org/vocab/InC/1.0/
© 2018. The American Astronomical Society. All rights reserved. Published in this repository with the kind permission of the publisher.
https://rightsstatements.org/vocab/InC/1.0/
doi:https://doi.org/10.3847/1538-4357/aad0f2
Näytä kaikki kuvailutiedot
Julkaisun pysyvä osoite on
https://urn.fi/URN:NBN:fi-fe2019032610039
Tiivistelmä

Abstract

Using a recently developed two-scale formalism to determine the magnetic helicity spectrum, we analyze synoptic vector magnetograms built with data from the Vector Spectromagnetograph instrument on the Synoptic Optical Long-term Investigations of the Sun telescope during 2010 January–2016 July. In contrast to an earlier study using only three Carrington rotations (CRs), our analysis includes 74 synoptic CR maps. We recover here bihelical spectra at different phases of solar cycle 24, where the net magnetic helicity in the majority of the data is consistent with a large-scale dynamo with helical turbulence operating in the Sun. More than 20% of the analyzed maps, however, show violations of the expected sign rule.

Kokoelmat