English
Related papers

Related papers: Active region upflows: 1. Multi-instrument observa…

200 papers

We present a study of molecular outflows using six molecular lines (including 12CO/13CO/C18O/HCO+(J = 1-0) and SiO/CS(J = 2-1)) toward nine nearby high-mass star-forming regions with accurate known distances. This work is based on the…

Astrophysics of Galaxies · Physics 2021-03-10 De-Jian Liu , Ye Xu , Ying-Jie Li , Sheng Zheng , Deng-Rong Lu , Chao-Jie Hao , Ze-Hao Lin , Shuai-Bo Bian , Li-Ming Liu

We observed three recurrent blowout jets in an active regio with Atmospheric Imaging Assembly (AIA) aboard the Solar Dynamics Observatory (SDO). Using Helioseismic Magnetic Imager (HMI) data. We found that the magnetic flux of an emerging…

Solar and Stellar Astrophysics · Physics 2025-04-16 Chang Zhou , Yang Guo , Guoyin Chen , Ye Qiu , M. D. Ding

The analysis of multiwavelength properties of propagating disturbances (PDs) using Hinode/EIS observations is presented. Quasi-periodic PDs were mostly interpreted as slow magnetoacoustic waves in early studies, but recently suggested to be…

Solar and Stellar Astrophysics · Physics 2015-01-19 Tongjiang Wang , Leon Ofman , Joseph M. Davila

We present results of the study of chromospheric and photospheric line-of-sight velocity fields in the young active region NOAA 11024. Multi-layer, multi-wavelength observational data were used for the analysis of the emerging flux in this…

Solar and Stellar Astrophysics · Physics 2012-12-07 N. N. Kondrashova , M. N. Pasechnik , S. N. Chornogor , E. V. Khomenko

Active regions (ARs) appear in the solar atmosphere as a consequence of the emergence of magnetic flux-ropes (FR). In this study, we use Bayesian methods to analyze line-of-sight magnetograms of emerging ARs. We employ a FR model consisting…

Solar and Stellar Astrophysics · Physics 2024-05-21 Mariano Poisson , Marcelo López Fuentes , Cristina H. Mandrini , Pascal Démoulin , Francisco Grings

Super-sonic downflows have been observed in transition region spectra above numerous sunspots; however, little research has been conducted to date into how persistent these signatures are within sunspots on time-scales longer than a few…

Solar and Stellar Astrophysics · Physics 2020-04-15 C. J. Nelson , S. Krishna Prasad , M. Mathioudakis

We take advantage of the HMI/SDO instrument to study the naked emergence of active regions from the first imprints of the magnetic field on the solar surface. To this end, we followed the first 24 hours in the life of two rather isolated…

Solar and Stellar Astrophysics · Physics 2015-06-11 Rebecca Centeno

We present observations of the quiet solar photosphere in the \ion{Fe}{1} lines at 6302 \AA where at least four different spatial locations exhibit upwards-directed supersonic flows. These upflows can only be detected in the circular…

Astrophysics · Physics 2009-11-10 H. Socas-Navarro , R. Manso

Spectroscopic observations at extreme and far ultraviolet wavelengths have revealed systematic upflows in the solar transition region and corona. These upflows are best seen in the network structures of the quiet Sun and coronal holes,…

Solar and Stellar Astrophysics · Physics 2021-03-17 Hui Tian , Louise Harra , Deborah Baker , David H. Brooks , Lidong Xia

Ubiquitous small-scale vortices have recently been found in the lower atmosphere of the quiet Sun in state-of-the-art solar observations and in numerical simulations. We investigate the characteristics and temporal evolution of a…

Solar and Stellar Astrophysics · Physics 2016-01-27 S. -H. Park , G. Tsiropoula , I. Kontogiannis , K. Tziotziou , E. Scullion , J. G. Doyle

We explore the general properties of near-surface flows around solar active regions. Helioseismic holography is applied to HMI Dopplergrams yielding nearly 5000 flow measurements of 336 unique active regions observed by the Solar Dynamics…

Solar and Stellar Astrophysics · Physics 2019-03-20 D. C. Braun

A magnetic channel - a series of polarity reversals separating elongated flux threads with opposite polarities - may be a manifestation of a highly non-potential magnetic configuration in active regions. To understand its formation we have…

Solar and Stellar Astrophysics · Physics 2015-05-19 Eun-Kyung Lim , Jongchul Chae , Ju Jing , Haimin Wang , Thomas Wiegelmann

To adequately constrain the frequency of energy deposition in active region cores in the solar corona, systematic comparisons between detailed models and observational data are needed. In this paper, we describe a pipeline for forward…

Solar and Stellar Astrophysics · Physics 2019-07-31 W. T. Barnes , S. J. Bradshaw , N. M. Viall

An active region filament in the upper chromosphere is studied using spectropolarimetric data in He I 10830 A from the GREGOR telescope. A Milne-Eddingon based inversion of the Unno-Rachkovsky equations is used to retrieve the velocity and…

Solar and Stellar Astrophysics · Physics 2020-09-30 K. Sowmya , A. Lagg , S. K. Solanki , J. S. Castellanos Durán

X-ray and EUV observations are an important diagnostic of various plasma parameters of the solar atmosphere during solar flares. Soft X-ray and EUV observations often show coronal sources near the top of flaring loops, while hard X-ray…

Solar and Stellar Astrophysics · Physics 2015-06-11 Marina Battaglia , Eduard P. Kontar

Solar coronal plasma composition is typically characterized by first ionization potential (FIP) bias. Using spectra obtained by Hinode's EUV Imaging Spectrometer (EIS) instrument, we present a series of large-scale, spatially resolved…

Solar and Stellar Astrophysics · Physics 2015-06-23 D. Baker , D. H. Brooks , P. Démoulin , S. L. Yardley , L. van Driel-Gesztelyi , D. M. Long , L. M. Green

To study the dynamical evolution of trans-equatorial loops (TELs) using imaging and spectroscopy. We have used the images recorded by the Atmospheric Imaging Assembly and the Helioseismic Magnetic Imager on-board the Solar Dynamics…

Solar and Stellar Astrophysics · Physics 2020-07-29 Avyarthana Ghosh , Durgesh Tripathi

We use UV spectral observations of active regions with the Interface Region Imaging Spectrograph (IRIS) to investigate the properties of the coronal FeXII 1349.4A emission at unprecedented high spatial resolution (~0.33"). We find that by…

Solar and Stellar Astrophysics · Physics 2016-08-17 Paola Testa , Bart De Pontieu , Viggo Hansteen

We observe plasma flows in cool loops using the Slit-Jaw Imager (SJI) onboard the Interface Region Imaging Spectrometer (IRIS). Huang et al. (2015) observed unusually broadened Si IV 1403 angstrom line profiles at the footpoints of such…

Solar and Stellar Astrophysics · Physics 2020-05-27 A. K. Srivastava , Yamini K. Rao , P. Konkol , K. Murawski , M. Mathioudakis , Sanjiv K. Tiwari , E. Scullion , J. G. Doyle , B. N. Dwivedi

Studying the dynamics of filaments at pre-eruption phase can shed light on the precursor of eruptive events. Such studies in high-resolution (in the order of 0.1") are highly desirable yet very rare so far. In this work, we present a…

Solar and Stellar Astrophysics · Physics 2017-06-14 Qin Li , Na Deng , Ju Jing , Haimin Wang