English
Related papers

Related papers: The horizontal internetwork magnetic field: numeri…

200 papers

Khomenko et al. estimate the mean magnetic field strength of the quiet Sun to be 20 G. The figure is smaller than several existing estimates, and it comes from the comparison between observed Zeeman polarization signals and synthetic…

Astrophysics · Physics 2009-11-11 J. Sanchez Almeida

We simulate the dynamics and the evolution of quiet Sun magnetic elements to produce a probability density function of the field strengths associated with such elements. The dynamics of the magnetic field are simulated through a numerical…

Astrophysics · Physics 2009-11-13 F. Berrilli , D. Del Moro , B. Viticchie

A 50 min time series of one-dimensional slit-spectrograms, taken in quiet sun at disk center, observed at the German Vacuum Tower Telescope (Observatorio del Teide), was used to study the global and spatial variations of different line…

Solar and Stellar Astrophysics · Physics 2013-03-14 K. G. Puschmann , M. Vazquez , J. A. Bonet , B. Ruiz Cobo , A. Hanslmeier

Full-disk measurements of the solar magnetic field by the Helioseismic and Magnetic Imager (HMI) are often used for magnetic field extrapolations, but its limited spatial and spectral resolution can lead to significant errors. We compare…

Solar and Stellar Astrophysics · Physics 2024-11-27 C. Beck , A. Prasad , Q. Hu , M. S. Yalim , S. Gosain , D. P. Choudhary

We have been monitoring yearly variation in the Sun's polar magnetic fields with the Solar Optical Telescope aboard {\it Hinode} to record their evolution and expected reversal near the solar maximum. All magnetic patches in the magnetic…

Solar and Stellar Astrophysics · Physics 2015-06-05 D. Shiota , S. Tsuneta , M. Shimojo , N. Sako , D. Orozco Suárez , R. Ishikawa

The propagation of solar waves through the sunspot of AR 9787 is observed using temporal cross-correlations of SOHO/MDI Dopplergrams. We then use three-dimensional MHD numerical simulations to compute the propagation of wave packets through…

Astrophysics · Physics 2009-11-13 R. Cameron , L. Gizon , T. L. Duvall

One of the main theories for heating of the solar corona is based on the idea that solar convection shuffles and tangles magnetic field lines to make many small-scale current sheets that, via reconnection, heat coronal loops. Tiwari et al…

Solar and Stellar Astrophysics · Physics 2025-05-08 V. Aparna , Sanjiv K. Tiwari , Ronald L. Moore , Navdeep K. Panesar , Brian Welsch , Bart De Pontieu , Aimee Norton

We investigate the ratio of the vertical and horizontal velocities of the photospheric plasma flows in the region of emerging magnetic fields on the Sun. We carried out a study of photospheric velocities during the first hours of the…

Solar and Stellar Astrophysics · Physics 2012-12-17 A. Khlystova

We present observational evidence for oscillations of magnetic flux density in the quiet areas of the Sun. The majority of magnetic fields on the solar surface have strengths of the order of or lower than the equipartition field (300-500…

We compare horizontal velocities, vertical magnetic fields and evolution of trees of fragmenting granules (TFG, also named families of granules) derived in the quiet Sun at disk center from observations at solar minimum and maximum of the…

Solar and Stellar Astrophysics · Physics 2018-04-11 J. M. Malherbe , T. Roudier , R. Stein , Z. Frank

Active region NOAA 11035 appeared in December 2009, early in the new solar activity cycle. This region achieved a delta sunspot ($\delta$-spot) configuration when parasitic flux emerged near the rotationally leading magnetic polarity and…

Solar and Stellar Astrophysics · Physics 2016-02-17 Sarah A. Jaeggli

We have studied the angular distribution of the magnetic field vector in the solar internetwork employing high-quality data (noise level $\sigma \approx 3\times 10^{-4}$ in units of the quiet-Sun intensity) at different latitudes recorded…

Solar and Stellar Astrophysics · Physics 2015-06-12 J. M. Borrero , P. Kobel

In addition to the `facular' brightening of active regions, the quiet Sun also contains a small scale magnetic field with associated brightenings in continuum radiation. We measure this contribution of quiet regions to the Sun's brightness…

Solar and Stellar Astrophysics · Physics 2011-08-11 R. S. Schnerr , H. C. Spruit

The heating and structure of the solar chromosphere depends on the underlying magnetic field, among other parameters. The lowest magnetic flux of the solar atmosphere is found in the quiet Sun internetwork and is thought to be provided by…

Solar and Stellar Astrophysics · Physics 2025-11-19 D. Przybylski , R. Cameron , S. K. Solanki , M. Rempel , S. Danilovic , J. Leenaarts

In this paper, we study the properties of solar granulation in a facular region from the photosphere up to the lower chromosphere. Our aim is to investigate the dependence of granular structure on magnetic field strength. We use…

Solar and Stellar Astrophysics · Physics 2015-06-05 R. Kostik , E. Khomenko

The magnetic fields in the solar polar region are important to our understanding of the internal dynamo process, the global coronal structure, and the origin of the solar wind. The inference of polar fields based on spectropolarimetric…

Solar and Stellar Astrophysics · Physics 2026-03-16 Bryan Yamashiro , Xudong Sun , Ivan Milić , Carlos Quintero Noda , Adur Pastor Yabar , Rebecca Centeno , Jiayi Liu , Milan Gošić , Kai Yang

Small-scale magnetic fields are not only the fundamental element of the solar magnetism, but also closely related to the structure of the solar atmosphere. The observations have shown that there is a ubiquitous tangled small-scale magnetic…

Solar and Stellar Astrophysics · Physics 2021-08-11 Yan Li , Qian-sheng Zhang , Tao Wu , Jie Su , Xing-hao Chen , Gui-fang Lin , Jian-heng Guo , Jie-ying Liu

It is widely believed that the heating of the chromosphere in quiet-Sun internetwork regions is provided by dissipation of acoustic waves that are excited by the convective motions close to the top of the convection zone and in the…

Astrophysics · Physics 2007-05-23 S. Wedemeyer-Böhm , O. Steiner , J. Bruls , W. Rammacher

Simultaneous measurement of line-of-sight (LOS) magnetic and velocity fields at the photosphere and chromosphere are presented. Fe I line at $\lambda6569$ and $H_{\alpha}$ at $\lambda6563$ are used respectively for deriving the physical…

Astrophysics · Physics 2009-11-13 K. Nagaraju , K. Sankarasubramanian , K. E. Rangarajan

Sunspots are the most spectacular manifestation of solar magnetism, yet, 99% of the solar surface remains 'quiet' at any time of the solar cycle. The quiet sun is not void of magnetic fields, though; they are organized at smaller spatial…

Solar and Stellar Astrophysics · Physics 2015-05-18 M. J. Martinez Gonzalez , R. Manso Sainz , A. Asensio Ramos , L. R. Bellot Rubio