English
Related papers

Related papers: A geometrical height scale for sunspot penumbrae

200 papers

High-resolution spectropolarimetric observations of active region NOAA 11271 were obtained with the spectro-polarimeter on board Hinode to analyze the properties of an anomalous flow in the photosphere in a sunspot penumbra. We detect a…

Solar and Stellar Astrophysics · Physics 2014-10-29 Rohan E. Louis , Christian Beck , Shibu K. Mathew , P. Venkatakrishnan

We study the extent to which Milne-Eddington inversions are able to retrieve and characterize the magnetic landscape of the solar poles from observations by the spectropolarimeter onboard Hinode. In particular, we evaluate whether a…

Solar and Stellar Astrophysics · Physics 2023-07-05 Rebecca Centeno , Ivan Milić , Matthias Rempel , Nariaki V. Nitta , Xudong Sun

The flows in and around sunspots are rich in detail. Starting with the Evershed flow along low-lying flow channels, which are cospatial with the horizontal penumbral magnetic fields, Evershed clouds may continue this motion at the periphery…

Solar and Stellar Astrophysics · Physics 2015-05-19 Carsten Denker , Meetu Verma

Sunspot penumbrae show a fine structure in continuum intensity that displays considerable dynamics. The magnetic field, in contrast, although also highly structured, has appeared to be relatively static. Here we report the discovery of…

Astrophysics · Physics 2009-11-13 Jun Zhang , S. Solanki , J. Woch

We introduce the notion of algebraic higher symmetry, which generalizes higher symmetry and is beyond higher group. We show that an algebraic higher symmetry in a bosonic system in $n$-dimensional space is characterized and classified by a…

Strongly Correlated Electrons · Physics 2020-10-21 Liang Kong , Tian Lan , Xiao-Gang Wen , Zhi-Hao Zhang , Hao Zheng

We recently presented evidence that stable umbra-penumbra boundaries are characterised by a distinct canonical value of the vertical component of the magnetic field, $B^{\rm stable}_{\rm ver}$. In order to trigger the formation of a…

Solar and Stellar Astrophysics · Physics 2016-12-28 Jan Jurcak , Nazaret Bello Gonzalez , Rolf Schlichenmaier , Reza Rezaei

Photometric and astrometric monitoring of directly imaged exoplanets will deliver unique insights into their rotational periods, the distribution of cloud structures, weather, and orbital parameters. As the host star is occulted by the…

Instrumentation and Methods for Astrophysics · Physics 2020-07-01 Steven P. Bos

The magnetic geometry of the solar atmosphere, combined with projection effects, makes it difficult to accurately map the propagation of ubiquitous waves in fibrillar structures. These waves are of interest due to their ability to carry…

The high spatial, temporal and spectral resolution achieved by Hinode instruments give much better understanding of the behavior of some elusive solar features, such as pores and naked sunspots. Their fast evolution and, in some cases,…

Solar and Stellar Astrophysics · Physics 2012-02-06 A. Sainz Dalda , S. Vargas Dominguez , T. D. Tarbell

We investigate the evolution of 5 granular-scale magnetic flux cancellations just outside the moat region of a sunspot by using accurate spectropolarimetric measurements and G-band images with the Solar Optical Telescope aboard Hinode. The…

Solar and Stellar Astrophysics · Physics 2015-05-18 M. Kubo , B. C. Low , B. W. Lites

We investigate p-mode absorption in a sunspot using SOHO/MDI high-resolution Doppler images. The Doppler power computed from a three and a half hour data set is used for studying the absorption in a sunspot. The result shows an enhancement…

Astrophysics · Physics 2008-09-11 Shibu K. Mathew

Recent numerical simulations and observations of sunspots show a significant amount of opposite polarity magnetic field within the sunspot penumbra. Most of the opposite polarity field is associated with convective downflows. We present an…

Solar and Stellar Astrophysics · Physics 2019-11-06 Lokesh Bharti , Matthias Rempel

We present the first interpretation of the Stokes profile asymmetries measured in the FeI 630 nm lines by SOT/SP, in both quiet Sun internetwork (IN) and network regions. The inversion is carried out under the hypothesis of MISMA, where the…

Solar and Stellar Astrophysics · Physics 2015-05-20 B. Viticchié , J. , Sánchez Almeida , D. Del Moro , F. Berrilli

High resolution and seeing-free spectroscopic observation of a decaying sunspot was done with the Solar Optical Telescope aboard Hinode satellite. The target was NOAA 10944 located in the west side of the solar surface from March 2 to March…

Astrophysics · Physics 2015-05-13 Hiroko Watanabe , Reizaburo Kitai , Kiyoshi Ichimoto , Yukio Katsukawa

The Helioseismic Magnetic Imager (HMI) onboard the Solar Dynamics Observatory (SDO) records line-of-sight Dopplergram images of convective flows on the surface. These images are used to obtain the multi-scale convective spectrum. We design…

Solar and Stellar Astrophysics · Physics 2021-08-09 Samarth G Kashyap , Shravan M Hanasoge

The aim of this work is to give new observational constraints on solar surface flows by determining the horizontal scale dependence of the velocity and intensity fields, as represented by their power spectra, and to offer some theoretical…

Solar and Stellar Astrophysics · Physics 2015-05-14 M. Rieutord , T. Roudier , F. Rincon , J. -M. Malherbe , N. Meunier , T. Berger , Z. Frank

We study the formation of a sunspot penumbra in the active region NOAA11024. We simultaneously observed the Stokes parameters of the photospheric iron lines at 1089.6 nm with the TIP and 617.3 nm with the GFPI spectropolarimeters along with…

Solar and Stellar Astrophysics · Physics 2011-11-15 Reza Rezaei , Nazaret Bello Gonzalez , Rolf Schlichenmaier

We analyzed the full Stokes spectra using simultaneous measurements of the photospheric (FeI 630.15 and 630.25 nm) and chromospheric (MgI b2 517.27 nm) lines. The data were obtained with the HAO/NSO Advanced Stokes Polarimeter, about a near…

Solar and Stellar Astrophysics · Physics 2015-05-19 Na Deng , Debi Prasad Choudhary , K. S. Balasubramaniam

This paper presents a method for estimating significant wave height (Hs) from sparse S_pectral P_oint using a T_ransformer-based approach (SPT). Based on empirical observations that only a minority of spectral points with strong power…

Signal Processing · Electrical Eng. & Systems 2026-01-09 Yi Zhou , Li Wang , Hang Su , Tian Wang

We develop a new estimation technique for recovering depth-of-field from multiple stereo images. Depth-of-field is estimated by determining the shift in image location resulting from different camera viewpoints. When this shift is not…

Applications · Statistics 2009-10-07 E. Anderes , B. Yu , V. Jovanovic , C. Moroney , M. Garay , A. Braverman , E. Clothiaux
‹ Prev 1 8 9 10 Next ›