English
Related papers

Related papers: A Twenty Year Decline in Solar Photospheric Magnet…

200 papers

The extended minimum of Solar Cycle 23, the extremely quiet solar-wind conditions prevailing, and the mini-maximum of Solar Cycle 24 drew global attention and many authors have since attempted to predict the amplitude of the upcoming Solar…

Solar and Stellar Astrophysics · Physics 2020-12-07 K. Sasikumar Raja , P. Janardhan , Susanta Kumar Bisoi , Madhusudan Ingale , Prasad Subramanian , K. Fujiki , Milan Maksimovic

We examine the temporal changes in both solar polar magnetic field (PMF) at latitudes $\ge$ $45^{\circ}$ and heliospheric magnetic field (HMF) at 1 AU during solar cycles 21--24 with emphasis on the recent activity changes after July 2015,…

Solar and Stellar Astrophysics · Physics 2020-08-05 Susanta Kumar Bisoi , P. Janardhan , S. Ananthakrishnan

Using both wavelet and Fourier analysis, a study has been undertaken of the changes in the quasi-periodic variations in solar photospheric fields in the build-up to one of the deepest solar minima experienced in the past 100 years. This…

Solar and Stellar Astrophysics · Physics 2015-06-15 Susanta Kumar Bisoi , P. Janardhan , D. Chakrabarty , S. Ananthakrishnan , Ankur Divekar

Longitudinal distributions of the photospheric magnetic field studied on the base of National Solar Observatory (Kitt Peak) data (1976 - 2003) displayed two opposite patterns during different parts of the 11-year solar cycle.…

Astrophysics · Physics 2007-12-17 E. S. Vernova , M. I. Tyasto , D. G. Baranov

Polarity imbalance of the photospheric magnetic field was studied using synoptic maps of NSO Kitt Peak (1976-2016). Imbalance of positive and negative fluxes was considered for the fields with strength B>50 G in the sunspot zone (5 deg - 40…

Solar and Stellar Astrophysics · Physics 2018-12-12 E. S. Vernova , M. I. Tyasto , D. G. Baranov , O. A. Danilova

Distribution of the positive and negative photospheric fields is studied on the base of synoptic maps of the photospheric magnetic field produced by the National Solar Observatory Kitt Peak (NSO Kitt Peak) for 1976-2016. In the analysis…

Solar and Stellar Astrophysics · Physics 2019-02-20 E. S. Vernova , M. I. Tyasto , D. G. Baranov , O. A. Danilova

Variations of the weak magnetic fields of the photosphere with periods of the order of the solar magnetic cycle were investigated. Synoptic maps of the photospheric magnetic field produced by NSO Kitt Peak for the period from 1978 to 2016…

Solar and Stellar Astrophysics · Physics 2023-07-18 E. S. Vernova , M. I. Tyasto , D. G. Baranov

The present study examines the response of the terrestrial magnetosphere to the long-term steady declining trends observed in solar magnetic fields and solar wind micro-turbulence levels since mid-1990's that has been continuing beyond the…

Solar and Stellar Astrophysics · Physics 2019-08-08 M. Ingale , P. Janardhan , S. K. Bisoi

The work is devoted to the study of periodic structures in the magnetic field of the photosphere. The polarity of the Sun's magnetic fields shows cyclicity with periods of 1-3 years, which is possibly due to quasi-biennial variations that…

Solar and Stellar Astrophysics · Physics 2025-07-08 Elena Vernova , Marta Tyasto , Dmitrii Baranov

Thirty-four years of WSO (Wilcox Solar Observatory) and thirteen years of SOHO/MDI (Michelson Doppler Imager on the Solar and Heliospheric Observatory) magnetograms have been studied to measure the east-west inclination angle, indicating…

Solar and Stellar Astrophysics · Physics 2010-03-23 Leyan Lo , Todd Hoeksema , Phil Scherrer

The Sun's magnetic field varies in multiple time scales. Observations show that the minimum between cycles 24 and 25 was the second consecutive minimum which was deeper and wider than several earlier minima. Since the active regions…

Solar and Stellar Astrophysics · Physics 2022-01-19 Kiran Jain , Niket Jain , Sushanta C. Tripathy , Mausumi Dikpati

The evolution of the photospheric magnetic field during the declining phase and minimum of Cycle 23 and the recent rise of Cycle 24 are compared with the behavior during previous cycles. We used longitudinal full-disk magnetograms from the…

Solar and Stellar Astrophysics · Physics 2012-08-28 Gordon Petrie

Synoptic magnetograms provide us with knowledge about the evolution of magnetic fields on the solar surface and present important information for forecasting future solar activity. In this work, poloidal and toroidal magnetic field…

Solar and Stellar Astrophysics · Physics 2020-02-19 Irina N. Kitiashvili

Among many other measurable quantities the summer of 2009 saw a considerable low in the radiative output of the Sun that was temporally coincident with the largest cosmic ray flux ever measured at 1AU. A hemispheric asymmetry in magnetic…

Photospheric magnetic fields were studied using the Kitt Peak synoptic maps for 1976-2003. Only strong magnetic fields (B>100 G) of the equatorial region were taken into account. The north-south asymmetry of the magnetic fluxes was…

Solar and Stellar Astrophysics · Physics 2014-05-27 E. S. Vernova , M. I. Tyasto , D. G. Baranov

We study the asymmetric distribution of weak photospheric magnetic field values in the two hemispheres separately using synoptic maps from SDO/HMI, SOLIS/VSM and WSO during solar cycles 21-24. We calculate the weak-field asymmetry (shift)…

Solar and Stellar Astrophysics · Physics 2019-10-09 Tibebu Getachew , Ilpo Virtanen , Kalevi Mursula

Recent studies of the heliospheric magnetic field (HMF) have detected interesting, systematic hemispherical and longitudinal asymmetries which have a profound significance for the understanding of solar magnetic fields. The in situ HMF…

Astrophysics · Physics 2009-11-10 K. Mursula , T. Hiltula

The Sun's surface field, especially the polar field, sets the boundary condition for the coronal and heliospheric magnetic fields, but also provides us insight into the dynamo process. The evolution of the polar fields results from the…

Solar and Stellar Astrophysics · Physics 2018-07-05 Jie Jiang , Jinbin Cao

Solar polar fields are essential for the solar cycle and the heliospheric magnetic field. Cycle 25 is now entering its declining phase, the critical period during which most of the cycle's polar fields are established. Therefore, reliable…

Solar and Stellar Astrophysics · Physics 2026-03-31 Ruihui Wang , Jie Jiang , Yukun Luo

The review presents analysis and physical interpretation of available statistical data about solar wind plasma and interplanetary magnetic field (IMF) properties as measured in-situ at 1 A.U. by numerous space experiments during time period…

Space Physics · Physics 2013-01-15 A. V. Dmitriev , A. V. Suvorova , I. S. Veselovsky
‹ Prev 1 2 3 10 Next ›