English
Related papers

Related papers: Evolution Of Super-Sonic Downflows In A Sunspot

200 papers

The high spatial and time resolution data obtained with SDO/AIA for the sunspot in active region NOAA 11131 on 08 December 2010 were analysed with the time-distance plot technique and the pixelised wavelet filtering method. Oscillations in…

Solar and Stellar Astrophysics · Physics 2014-09-17 R. Sych , V. M. Nakariakov

In this Letter we present a seismological detection of a rising motion of magnetic flux in the shallow convection zone of the Sun, and show estimates of the emerging speed and its decelerating nature. In order to evaluate the speed of…

Solar and Stellar Astrophysics · Physics 2015-06-15 Shin Toriumi , Stathis Ilonidis , Takashi Sekii , Takaaki Yokoyama

Solar flares are rapid energy release phenomena that appear as bright ribbons in the chromosphere and high-temperature loops in the corona, respectively. Supra-arcade Downflows (SADs) are plasma voids that first come out above the flare…

Solar and Stellar Astrophysics · Physics 2021-07-21 Z. F. Li , X. Cheng , M. D. Ding , Katharine K. Reeves , DeOndre Kittrell , Mark Weber , David E. McKenzie

We present results derived from the analysis of spectropolarimetric measurements of active region AR12546, which represents one of the largest sunspots to have emerged onto the solar surface over the last $20$ years. The region was observed…

Solar and Stellar Astrophysics · Physics 2018-12-26 M. Stangalini , S. Jafarzadeh , I. Ermolli , R. Erdélyi , D. B. Jess , P. H. Keys , F. Giorgi , M. Murabito , F. Berrilli , D. Del Moro

We study the spectroscopic evolution of superluminous supernovae (SLSNe) later than 100 days after maximum light. We present new data for Gaia16apd and SN2017egm, and analyse these with a larger sample comprising 41 spectra of 12 events.…

High Energy Astrophysical Phenomena · Physics 2019-01-30 Matt Nicholl , Edo Berger , Peter K Blanchard , Sebastian Gomez , Ryan Chornock

ASASSN-14li is a low-redshift ($z= 0.0206$) tidal disruption event (TDE) that has been studied extensively across the entire electromagnetic spectrum, and has provided one of the most sensitive measurements of a TDE to-date. Its X-ray…

High Energy Astrophysical Phenomena · Physics 2024-01-24 Yukta Ajay , Dheeraj R. Pasham , Thomas Wevers , Eric R. Coughlin , Francesco Tombesi , Muryel Guolo , James F. Steiner

Sunward-flowing voids above post-coronal mass ejection (CME) flare arcades were first discovered using the soft X-ray telescope (SXT) aboard Yohkoh and have since been observed with TRACE (extreme ultra-violet (EUV)), SOHO/LASCO (white…

Solar and Stellar Astrophysics · Physics 2015-05-27 Sabrina L. Savage , David E. McKenzie

We observed small scale magnetic flux emergence in a sunspot moat region by the Solar Optical Telescope (SOT) aboard the Hinode satellite. We analyzed filtergram images observed in the wavelengths of Fe 6302 angstrom, G-band and Ca II H. In…

High-resolution observations of the solar chromosphere and transition region often reveal surge-like oscillatory activities above sunspot light bridges. These oscillations are often interpreted as intermittent plasma jets produced by…

Solar and Stellar Astrophysics · Physics 2017-03-29 Jingwen Zhang , Hui Tian , Jiansen He , Linghua Wang

Sunward-flowing voids above post-coronal mass ejection flare arcades, also known as supra-arcade downflows (SADs), have characteristics consistent with post-reconnection magnetic flux tube cross-sections. Applying semi-automatic detection…

Solar and Stellar Astrophysics · Physics 2012-01-26 Sabrina Savage , David McKenzie

Drift pairs are an unusual type of fine structure sometimes observed in dynamic spectra of solar radio emission. They appear as two identical short narrowband drifting stripes separated in time; both positive and negative frequency drifts…

Solar and Stellar Astrophysics · Physics 2019-10-23 Alexey Kuznetsov , Eduard Kontar

The long term study of the Sun is necessary if we are to determine the evolution of sunspot properties and thereby inform modeling of the solar dynamo, particularly on scales of a solar cycle. We aim to determine a number of sunspot…

Solar and Stellar Astrophysics · Physics 2011-08-23 Fraser T. Watson , Lyndsay Fletcher , Stephen Marshall

(Context) Many physical parameters change with time in star forming regions. Here we attempt to correlate changes in infall and outflow motions in high mass star forming regions with evolutionary stage using JCMT observations. (Aims) From a…

Astrophysics of Galaxies · Physics 2015-06-03 P. D. Klaassen , L. Testi , H. Beuther

Supra-arcade downflows (SADs) are infrequent, wiggly opaque structures observed to descend through the solar corona, mostly in EUV and soft X-ray frequencies. From their physical characteristics, SADs have been interpreted as voided…

Solar and Stellar Astrophysics · Physics 2022-03-04 Ernesto Zurbriggen , C. Guillermo Giménez de Castro , Andrea Costa , Mariana Cécere , Caius L. Selhorst

We study the line profiles of a range of transition region (TR) emission lines observed in typical quiet Sun regions. In magnetic network regions, the Si IV 1402\AA{}, C IV 1548\AA{}, N V 1238\AA{}, O VI 1031\AA{}, and Ne VIII 770\AA{}…

Solar and Stellar Astrophysics · Physics 2014-11-20 Scott W. Mcintosh , Bart De Pontieu

We find evidence for the first observation of the parametric decay instability (PDI) in the lower solar atmosphere. Specifically, we find that the power spectrum of density fluctuations near the solar transition region resembles the power…

Solar and Stellar Astrophysics · Physics 2022-07-20 Michael Hahn , Xiangrong Fu , Daniel Wolf Savin

Light walls, as ensembles of oscillating bright structures rooted in sunspot light bridges, have not been well studied, although they are important for understanding sunspot properties. Using the Interface Region Imaging Spectrograph and…

Solar and Stellar Astrophysics · Physics 2017-07-19 Shuhong Yang , Jun Zhang , Robertus Erdélyi , Yijun Hou , Xiaohong Li , Limei Yan

In this contribution we describe some recent observations of high-speed magnetized flows in the quiet Sun granulation. These observations were carried out with the Imaging Magnetograph eXperiment (IMaX) onboard the stratospheric balloon…

The blazar AO 0235+164 was claimed to show a quasi-periodic behaviour in the radio and optical bands. Moreover, an extra emission component contributing to the UV and soft X-ray flux was detected, whose nature is not yet clear. A predicted…

Astrophysics · Physics 2009-11-13 C. M. Raiteri , M. Villata , V. M. Larionov , M. F. Aller , U. Bach

We study the velocity structure of penumbral filaments in the deep photosphere to obtain direct evidence for the convective nature of sunspot penumbrae. A sunspot was observed at high spatial resolution with the 1-m Swedish Solar Telescope…

Solar and Stellar Astrophysics · Physics 2015-05-28 Jayant Joshi , A. Pietarila , J. Hirzberger , S. K. Solanki , R. Aznar Cuadrado , L. Merenda
‹ Prev 1 4 5 6 7 8 10 Next ›