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Observations from the Hinode/XRT telescope and STEREO/SECCHI/EUVI are utilized to study polar coronal jets and plumes. The study focuses on the temporal evolution of both structures and their relationship. The data sample, spanning April…

Astrophysics · Physics 2009-11-13 N. -E. Raouafi , G. J. D. Petrie , A. A. Norton , C. J. Henney , S. K. Solanki

Coronal plumes are long, ray-like, open structures, which have been considered as possible sources for the solar wind. Their origin in the largely unipolar coronal holes has long been a mystery. Earlier spectroscopic and imaging…

Solar and Stellar Astrophysics · Physics 2022-07-06 Pankaj Kumar , Judith T. Karpen , Vadim M. Uritsky , Craig E. Deforest , Nour E. Raouafi , C. Richard DeVore

We present the first results of simulations of giant polar plumes and coronal flows. We use a 2.5D axisymmetric MHD numerical model of an isothermal corona and slow solar wind. A plume is generated just above asmall magnetic bipole embedded…

Solar and Stellar Astrophysics · Physics 2014-11-20 R. Pinto , R. Grappin , J. Leorat

Coronal plumes are bright magnetic funnels found in quiet regions (QRs) and coronal holes (CHs). They extend high into the solar corona and last from hours to days. The heating processes of plumes involve dynamics of the magnetic field at…

Solar and Stellar Astrophysics · Physics 2018-07-25 Ellis A. Avallone , Sanjiv K. Tiwari , Navdeep K. Panesar , Ronald L. Moore , Amy Winebarger

We characterize the orientation of polar plumes as a tracer of the large-scale coronal magnetic field configuration. We monitor in particular the north and south magnetic pole locations and the magnetic opening during 2007-2008 and provide…

Solar and Stellar Astrophysics · Physics 2015-06-17 Judith de Patoul , Bernd Inhester , Robert Cameron

To understand the formation mechanism of large plumes in solar prominences, we investigate the formation process of two such phenomena. We studied the dynamic and thermal properties of two large plumes using observations from New Vacuum…

Solar and Stellar Astrophysics · Physics 2022-03-14 Jincheng Wang , Xiaoli Yan , Zhike Xue , Liheng Yang , Qiaoling Li , Hechao Chen , Chun Xia , Zhong Liu

Polarimetric radio observations of the Sun can provide rich information about emission mechanisms and the propagation medium. For the past five decades, solar polarimetric studies at low radio frequencies have almost always assumed the…

Solar and Stellar Astrophysics · Physics 2025-08-05 Soham Dey , Devojyoti Kansabanik , Divya Oberoi , Surajit Mondal

Using all available multi-component radio pulse profiles for pulsars with medium to long periods and good polarisation data, we have constructed a two-dimensional image of the mean radio beamshape. This shows a peak near the centre of the…

Astrophysics · Physics 2009-10-31 J. L. Han , R. N. Manchester

Polarization is a basic property of light and is fundamentally linked to the internal geometry of a source of radiation. Polarimetry complements photometric, spectroscopic, and imaging analyses of sources of radiation and has made possible…

Instrumentation and Methods for Astrophysics · Physics 2017-01-18 S. Trippe

We report on full-polarization radio observations of the Perseus cluster (Abell 426) using the Westerbork Synthesis Radio Telescope (WSRT) at wavelengths from 81-95 cm. We have employed a novel technique, Rotation Measure synthesis…

Astrophysics · Physics 2009-11-13 A. G. de Bruyn , M. A. Brentjens

POLAR is a compact polarimeter dedicated to measure the polarization of GRBs between 50-300 keV. The light collection of 200*6*6mm3 plastic bars has been simulated and optimized in order to get uniform response to x-rays at different points…

Instrumentation and Methods for Astrophysics · Physics 2009-07-17 Yongwei Dong , Yanguo Li , Bobing Wu , Yongjie Zhang , Shuangnan Zhang

An estimate is made of the thickness of the radar-bright deposits in craters near to the north pole of Mercury. To construct an objective set of craters for this measurement, an automated crater finding algorithm is developed and applied to…

Earth and Planetary Astrophysics · Physics 2016-12-21 Vincent R. Eke , David J. Lawrence , Luıs F. A. Teodoro

Self-polar polytopes are convex polytopes that are equal to an orthogonal transformation of their polar sets. These polytopes were first studied by Lov\'{a}sz as a means of establishing the chromatic number of distance graphs on spheres,…

Combinatorics · Mathematics 2019-02-05 Alathea Jensen

The topic of wind-clumping has been the subject of much activity in recent years, due to the impact that it can have on derived mass-loss rates. Here we present an alternative method of investigating wind-clumping, that of polarimetry. We…

Astrophysics · Physics 2007-05-23 Ben Davies , Jorick S. Vink , Rene D. Oudmaijer

SOUTH POL will be a survey of the Southern sky in optical polarized light. It will use a newly designed polarimetric module at an 80cm Robotic Telescope. Telescope and polarimeter will be installed at CTIO, Chile, in late 2012. The initial…

We present EIS/Hinode & SUMER/SoHO joint observations allowing the first spectroscopic detection of accelerating disturbances as recorded with coronal lines in inter-plume and plume regions of a polar coronal hole. From time-distance…

Solar and Stellar Astrophysics · Physics 2010-06-28 G. R. Gupta , D. Banerjee , L. Teriaca , S. Imada , S. Solanki

From the South Pole, microthermal turbulence within a narrow surface boundary layer some 200m thick provides the dominant contribution to the astronomical seeing. We present results for the seeing at a wavelength of 2.4um. The narrow…

Astrophysics · Physics 2009-11-07 RD Marks

Traditional pulsar polarization sweep analysis starts from the point dipole rotating vector model (RVM) approximation. If augmented by a measurement of the sweep phase shift, one obtains an estimate of the emission altitude (Blaskiewicz,…

High Energy Astrophysical Phenomena · Physics 2015-06-05 H. A. Craig , Roger W. Romani

Very little is known about the polarimetric properties of CH stars and carbon-enhanced metal-poor (CEMP) stars, although many of these objects have been studied in detail both photometrically and spectroscopically. We aim to derive…

Solar and Stellar Astrophysics · Physics 2015-06-12 Aruna Goswami , Drisya Karinkuzhi

Based on SDSS data, we have selected a sample of nine edge-on spiral galaxies with bulges whose major axes show a high inclination to the disk plane. Such objects are called polar-bulge galaxies. They are similar in their morphology to…

Astrophysics of Galaxies · Physics 2016-01-20 V. P. Reshetnikov , S. S. Savchenko , A. V. Mosenkov , N. Ya. Sotnikova , D. V. Bizyaev