Log in

Relevant bibliographies by topics / Corona polarization / Journal articles

To see the other types of publications on this topic, follow the link: Corona polarization.

Journal articles on the topic 'Corona polarization'

Author: Grafiati

Published: 6 September 2023

Last updated: 31 July 2025

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the top 50 journal articles for your research on the topic 'Corona polarization.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.

1

Ursini, F., G. Matt, S. Bianchi, A. Marinucci, M. Dovčiak, and W. Zhang. "Prospects for differentiating extended coronal geometries in AGNs with the IXPE mission." Monthly Notices of the Royal Astronomical Society 510, no. 3 (2021): 3674–87. http://dx.doi.org/10.1093/mnras/stab3745.

Full text

Abstract:

ABSTRACT X-ray polarimetry can potentially constrain the unknown geometrical shape of active galactic nucleous (AGN) coronae. We present simulations of the X-ray polarization signal expected from AGN coronae, assuming three different geometries, namely slab, spherical, and conical. We use the fully relativistic Monte Carlo Comptonization code monk to compute the X-ray polarization degree and angle. We explore different coronal parameters such as shape, size, location, and optical depth. Different coronal geometries give a significantly different X-ray polarization signal. A slab corona yields

APA, Harvard, Vancouver, ISO, and other styles

2

Hebbur Dayananda, Supriya, Ángel de Vicente, Tanausú del Pino Alemán, Javier Trujillo Bueno, and Nataliia G. Shchukina. "P-CORONA: A New Tool for Calculating the Intensity and Polarization of Coronal Lines in 3D Models of the Solar Corona." Astrophysical Journal 987, no. 1 (2025): 39. https://doi.org/10.3847/1538-4357/add32e.

Full text

Abstract:

Abstract The critical need to study the magnetic field in the solar corona is highlighted by recent observational facilities, such as the Daniel K. Inouye Solar Telescope and Aditya-L1. A powerful tool for probing the magnetism of the solar corona is forward modeling of the intensity and polarization of coronal emission lines in three-dimensional (3D) magnetohydrodynamic models. Here we present P-CORONA, a new spectral synthesis code designed to calculate the intensity and polarization of coronal lines in 3D models of the solar corona, taking into account the symmetry breaking induced by magne

APA, Harvard, Vancouver, ISO, and other styles

3

Liang, Y., Z. Q. Qu, Y. J. Chen, Y. Zhong, Z. M. Song, and S. Y. Li. "Registration and imaging polarimetry of the Fe 6374 Å red coronal line during the 2017 total solar eclipse." Monthly Notices of the Royal Astronomical Society 503, no. 4 (2021): 5715–29. http://dx.doi.org/10.1093/mnras/stab463.

Full text

Abstract:

ABSTRACT Strict registration is critical for imaging polarimetry; a highly accurate registration approach to the coronal image and imaging polarimetry of the Fe 6374 Å red coronal line have been researched in this paper. In order to improve the registration accuracy, this paper proposes the idea of image enhancement based on blind deconvolution combined with noise-adaptive fuzzy equalization algorithms. After image enhancement, the cross-correlation registration algorithm achieves better results. To diagnose a low-temperature corona, the polarization brightness of the red coronal line data and

APA, Harvard, Vancouver, ISO, and other styles

4

Merzlyakov, V., Ts Tsvetkov, L. Starkova, and R. Miteva. "Polarization of white-light solar corona and sky polarization effect during total solar eclipse on March 29, 2006." Serbian Astronomical Journal, no. 199 (2019): 83–87. http://dx.doi.org/10.2298/saj190620005m.

Full text

Abstract:

Ground-based total solar eclipse observations are still the key method for coronal investigations. The question about its white-light degree of polarization remains unanswered. There are hypotheses claiming that the degree of polarization in certain regions of the corona may be higher than the maximal theoretically predicted value determined by Thomson scattering. We present polarization of the white-light solar corona observations obtained by three different teams during the March 29, 2006 solar total eclipse. We give an interpretation on how the polarization of the sky impacts brightness of

APA, Harvard, Vancouver, ISO, and other styles

5

Isobe, Syuzo, Tomohiro Hirayama, Naoshi Baba, and Noriaki Miura. "Optical Coronal Polarization and Solar Dust Ring." Publications of the Astronomical Society of Japan 39, no. 4 (1987): 667–77. https://doi.org/10.1093/pasj/39.4.667.

Full text

Abstract:

Abstract Observations of the outer solar corona on the Java island were carried out on June 11, 1983, at a 30-km altitude using a B-15 balloon. At 5325, 5965, 7200, and 8015Å, data on polarizations in a field of 5° × 5° centered nearly on the sun were obtained. Our contour maps of polarization are the first of the two-dimensional polarization distribution covering wide area. An excess of polarization at the four wavelengths was found in the ecliptic plane and at the location of a coronal streamer. High polarization at the coronal streamer is caused mainly by coronal electrons, but dust grains

APA, Harvard, Vancouver, ISO, and other styles

6

Lebedev, A. N., I. A. Belenko, O. I. Bougaenko, et al. "Eclipse Polarimetric Research of Prominences." International Astronomical Union Colloquium 167 (1998): 66–69. http://dx.doi.org/10.1017/s0252921100047308.

Full text

Abstract:

AbstractA polarization analysis of E–limb prominences on November 3, 1994 is presented. Photometry and data reduction of 24 prominence pictures based on IDL software and Stokes–vector presentation and applied to Hα emission resulted in an accuracy of 1–1.5% in determination of the polarization degree and of 1.5–2.0° in the polarization direction. Distributions of polarization degree (polarization images) for prominences and the “white light” corona are presented. A polarization degree of 2–5% for prominences and 10–25% for the nearby white light corona are found. The polarization direction is

APA, Harvard, Vancouver, ISO, and other styles

7

Patel, Ritesh, Daniel B. Seaton, Amir Caspi, et al. "A Chromatic Treatment of Linear Polarization in the Solar Corona at the 2023 Total Solar Eclipse." Research Notes of the AAS 7, no. 11 (2023): 241. http://dx.doi.org/10.3847/2515-5172/ad0b0d.

Full text

Abstract:

Abstract The broadband solar K-corona is linearly polarized due to Thomson scattering. Various strategies have been used to represent coronal polarization. Here, we present a new way to visualize the polarized corona, using observations from the 2023 April 20 total solar eclipse in Australia in support of the Citizen CATE 2024 project. We convert observations in the common four-polarizer orthogonal basis (0°, 45°, 90°, & 135°) to −60°, 0°, and +60° (MZP) polarization, which is homologous to R, G, B color channels. The unique image generated provides some sense of how humans might visualize

APA, Harvard, Vancouver, ISO, and other styles

8

Chattopadhyay, Tanmoy, Abhay Kumar, A. R. Rao, et al. "High Hard X-Ray Polarization in Cygnus X-1 Confined to the Intermediate Hard State: Evidence for a Variable Jet Component." Astrophysical Journal Letters 960, no. 1 (2023): L2. http://dx.doi.org/10.3847/2041-8213/ad118d.

Full text

Abstract:

Abstract Cygnus X-1, the well-known accreting black hole system, exhibits several observational features hinting at an intricate interplay between the accretion disk, its atmosphere known as the corona, and the putative relativistic jet. It has been extensively studied using all available observational methods, including using the newly available technique of sensitive X-ray polarimetry. X-ray polarization characteristics are distinct for coronal and jet emissions. The low X-ray polarization measured below ∼100 keV is understood as arising from the corona. In contrast, the high polarization me

APA, Harvard, Vancouver, ISO, and other styles

9

Kulidzanishvili, V., A. Mayer, V. Mayer, and S. Danik. "The Corona Electropolarimetry during July 11, 1991 Solar Eclipse." International Astronomical Union Colloquium 144 (1994): 529–33. http://dx.doi.org/10.1017/s0252921100025987.

Full text

Abstract:

AbstractThe electropolarimetry of July 11, 1991 eclipse solar corona using the new photoelectric polarimeter of Abastumani Astrophysical Observatory of the Georgian Academy of Sciences, equipped with the IBM computer, is described in this paper.By means of measurable values the isopolarization lines were constructed, which turned out to be stretched along the coronal streamers. The polarization plane has, entirely, radial direction; however, small but real deviations from radiality were established. The errors of measurements of intensity, polarization degree and polarization plane direction a

APA, Harvard, Vancouver, ISO, and other styles

10

Megha, A., M. Sampoorna, K. N. Nagendra, and K. Sankarasubramanian. "Coronal magnetic field measurements using forbidden emission lines." Proceedings of the International Astronomical Union 13, S340 (2018): 61–62. http://dx.doi.org/10.1017/s1743921318001023.

Full text

Abstract:

AbstractThe polarization measurement of coronal forbidden emission lines is the most promising method of determining the direction of magnetic fields in the corona. A classical theory for the forbidden lines was presented in Megha et al. (2017) for the case of arbitrary strength magnetic fields. Here we apply that theoretical formalism to study the effect of density distributions, magnetic field configurations, and velocity fields on the Stokes profiles formed in corona. For illustrations we use the atomic parameters of the [Fe xiii] 10747 Å coronal forbidden line.

APA, Harvard, Vancouver, ISO, and other styles

11

Shchukina, Nataliia G., Javier Trujillo Bueno, Supriya Hebbur Dayananda, Rafael Manso Sainz, and Andrii V. Sukhorukov. "Coronal Magnetometry with EUV Permitted Lines." Astrophysical Journal 988, no. 1 (2025): 33. https://doi.org/10.3847/1538-4357/addc61.

Full text

Abstract:

Abstract A major challenge in solar physics is to obtain empirical information on the magnetic field of the million-degree plasma of the solar corona. To this end, we need observables of the solar radiation sensitive to the coronal magnetic field. The most familiar observables are the polarization signals of visible and near-infrared forbidden lines of highly ionized species and some ultraviolet permitted lines, like hydrogen Lyα. While the coronal radiation in these spectral lines can only be detected for off-limb lines of sight, the coronal radiation from permitted extreme ultraviolet (EUV)

APA, Harvard, Vancouver, ISO, and other styles

12

Khan, Raveena, Sarah E. Gibson, Roberto Casini, and K. Nagaraju. "Extreme-ultraviolet Polarimetric Diagnostics of the Solar Corona: The Hanle Effect of Ne viii 770 Å." Astrophysical Journal 971, no. 1 (2024): 27. http://dx.doi.org/10.3847/1538-4357/ad55ed.

Full text

Abstract:

Abstract Magnetic fields are the primary driver of the plasma thermodynamics in the upper solar atmosphere, especially in the corona. However, magnetic field measurements in the solar corona are sporadic, thereby limiting us from the complete understanding of physical processes occurring in the coronal plasma. In this paper, we explore the diagnostic potential of a coronal emission line in the extreme-ultraviolet, i.e., Ne viii 770 Å, to probe the coronal magnetic fields. We utilize 3D “Magnetohydrodynamic Algorithm outside a Sphere” models as input to the FORWARD code to model polarization in

APA, Harvard, Vancouver, ISO, and other styles

13

Zhang, J. W., F. K. Gao, H. C. Sun, C. Putson, and R. T. Liu. "Electrostrictive energy conversion property of cellular electrets after corona discharge." International Journal of Modern Physics B 32, no. 07 (2018): 1850069. http://dx.doi.org/10.1142/s0217979218500698.

Full text

Abstract:

In this paper, the authors present the electrostrictive energy conversion ability of cellular electrets after the high-voltage corona polarization. Moreover, the electrostrictive effect of such foamed polymer before and after corona polarization has also been compared and discussed. The enhancement of electrostrictive effect of cellular electrets after corona polarization was observed. In particular, the impact on the electrostrictive effect of the macroscopic electric dipoles inside of cellular polymer which are generated by high-voltage corona poling procedure has been investigated. The pres

APA, Harvard, Vancouver, ISO, and other styles

14

Saade, M. Lynne, Philip Kaaret, Ioannis Liodakis, and Steven R. Ehlert. "A Comparison of the X-Ray Polarimetric Properties of Stellar and Supermassive Black Holes." Astrophysical Journal 974, no. 1 (2024): 101. http://dx.doi.org/10.3847/1538-4357/ad73a3.

Full text

Abstract:

Abstract X-ray polarization provides a new way to probe accretion geometry in black hole systems. If the accretion geometry of black holes is similar regardless of mass, we should expect the same to be true of their polarization properties. We compare the polarimetric properties of all nonblazar black holes observed with the Imaging X-ray Polarimetry Explorer. We find that their polarization properties are very similar, particularly in the hard state, where the corona dominates. This tentatively supports the idea that stellar and supermassive black holes share a common coronal geometry.

APA, Harvard, Vancouver, ISO, and other styles

15

Liu, Yu, Haosheng Lin, and Jeff Kuhn. "Coronal magnetic fields from the inversion of linear polarization measurements." Proceedings of the International Astronomical Union 5, S264 (2009): 96–98. http://dx.doi.org/10.1017/s174392130999247x.

Full text

Abstract:

AbstractReal 3-D coronal magnetic field reconstruction is expected to be made based on the technologies of IR spectrometry and tomography, in which the data from other wavelengths can be used as critical reference. Our recent studies focused on this issue are briefly reviewed in this paper. Liu & Lin (2008) first evaluated the validity of potential field source surface model applied to one of five limb regions in the corona by comparing the theoretical polarization maps with SOLARC observations in the IR Fe XIII 10747 Å forbidden coronal emission line (CEL). The five limb coronal regions w

APA, Harvard, Vancouver, ISO, and other styles

16

Gelfreikh, G. B., V. M. Bogod, V. E. Abramov-Maximov, and S. V. Tsvetkov. "Measurements of Solar Magnetic Fields Using Radio Observations with the RATAN-600." International Astronomical Union Colloquium 141 (1993): 271–74. http://dx.doi.org/10.1017/s0252921100029213.

Full text

Abstract:

AbstractThree ways of measuring magnetic fields in the corona and chromosphere have been developed based on spectral polarization observations with high spatial resolution using the radio telescope RATAN-600. The methods rely on effects from the theory of the generation and propagation of microwaves in the solar atmosphere: thermal bremsstrahlung, thermal cyclotron emission, and inversion of the polarization sign in quasi-transverse field regions. The new radio spectrograph (PAS) at the RATAN-600 resulted in higher accuracy measurements of the strength and structure of coronal magnetic fields.

APA, Harvard, Vancouver, ISO, and other styles

17

Saint-Hilaire, Pascal, Juan Carlos Martínez Oliveros, and Hugh S. Hudson. "Thomson Scattering in the Lower Corona in the Presence of Sunspots." Astrophysical Journal 923, no. 2 (2021): 276. http://dx.doi.org/10.3847/1538-4357/ac2f9b.

Full text

Abstract:

Abstract Polarized scattered light from low (few tens of megameter altitudes) coronal transients has been recently reported in Solar Dynamics Observatory/Helioseismic and Magnetic Image (HMI) observations. In a classic paper, Minnaert (1930) provided an analytic theory of polarization via electron scattering in the corona. His work assumed axisymmetric input from the photosphere with a single-parameter limb-darkening function. This diagnostic has recently been used to estimate the free-electron number and mass of HMI transients near the solar limb, but it applies equally well to any coronal ma

APA, Harvard, Vancouver, ISO, and other styles

18

Gelfreikh, G. B. "Radio Measurements of Coronal Magnetic Fields." International Astronomical Union Colloquium 144 (1994): 21–28. http://dx.doi.org/10.1017/s0252921100024933.

Full text

Abstract:

AbstractA review of methods of measuring magnetic fields in the solar corona using spectral-polarization observations at microwaves with high spatial resolution is presented. The methods are based on the theory of thermal bremsstrahlung, thermal cyclotron emission, propagation of radio waves in quasi-transverse magnetic field and Faraday rotation of the plane of polarization. The most explicit program of measurements of magnetic fields in the atmosphere of solar active regions has been carried out using radio observations performed on the large reflector radio telescope of the Russian Academy

APA, Harvard, Vancouver, ISO, and other styles

19

Krawczynski, H., and B. Beheshtipour. "New Constraints on the Spin of the Black Hole Cygnus X-1 and the Physical Properties of its Accretion Disk Corona." Astrophysical Journal 934, no. 1 (2022): 4. http://dx.doi.org/10.3847/1538-4357/ac7725.

Full text

Abstract:

Abstract We present a new analysis of NuSTAR and Suzaku observations of the black hole Cygnus X-1 in the intermediate state. The analysis is performed using kerrC, a new model for analyzing spectral and spectropolarimetric X-ray observations of black holes. kerrC builds on a large library of simulated black holes in X-ray binaries. The model accounts for the X-ray emission from a geometrically thin, optically thick accretion disk, the propagation of the X-rays through the curved black hole spacetime, the reflection off the accretion disk, and the Comptonization of photons in coronae of differe

APA, Harvard, Vancouver, ISO, and other styles

20

Ayala, Alejandro, Isabel Dominguez, Ivonne Maldonado та Maria Elena Tejeda-Yeomans. "An Improved Core-Corona Model for Λ and Λ Polarization in Relativistic Heavy-Ion Collisions". Particles 6, № 1 (2023): 405–15. http://dx.doi.org/10.3390/particles6010022.

Full text

Abstract:

Due to its sensitivity to the dynamics of strongly interacting matter subject to extreme conditions, hyperon global polarization has become an important observable to study the system created in relativistic heavy-ion collisions. Recently, the STAR and HADES collaborations have measured the global polarization of both Λ and Λ¯ produced in semi-central collisions in a wide range of collision energies. The polarization excitation functions show an increasing trend as the collision energy decreases, with the increase being more pronounced for the Λ¯. In this work, we make a summary of a core-coro

APA, Harvard, Vancouver, ISO, and other styles

21

Veledina, Alexandra, Fabio Muleri, Michal Dovčiak, et al. "Discovery of X-Ray Polarization from the Black Hole Transient Swift J1727.8−1613." Astrophysical Journal Letters 958, no. 1 (2023): L16. http://dx.doi.org/10.3847/2041-8213/ad0781.

Full text

Abstract:

Abstract We report the first detection of the X-ray polarization of the bright transient Swift J1727.8−1613 with the Imaging X-ray Polarimetry Explorer. The observation was performed at the beginning of the 2023 discovery outburst, when the source resided in the bright hard state. We find a time- and energy-averaged polarization degree of 4.1% ± 0.2% and a polarization angle of 2.°2 ± 1.°3 (errors at 68% confidence level; this translates to ∼20σ significance of the polarization detection). This finding suggests that the hot corona emitting the bulk of the detected X-rays is elongated, rather t

APA, Harvard, Vancouver, ISO, and other styles

22

Sidaravicius, J., T. Lozovsky, J. Jurksus, R. Maldzius, K. Backfolk, and P. Sirviö. "Polarization behaviour of paper during corona charging." Journal of Electrostatics 71, no. 1 (2013): 35–40. http://dx.doi.org/10.1016/j.elstat.2012.11.003.

Full text

APA, Harvard, Vancouver, ISO, and other styles

23

Badalyan, O. G., and M. A. Livshits. "Analysis of the green-line corona polarization." Astronomical & Astrophysical Transactions 20, no. 3 (2001): 575–86. http://dx.doi.org/10.1080/10556790108213602.

Full text

APA, Harvard, Vancouver, ISO, and other styles

24

Spangler, Steven R., and Catherine A. Whiting. "Radio remote sensing of the corona and the solar wind." Proceedings of the International Astronomical Union 4, S257 (2008): 529–41. http://dx.doi.org/10.1017/s1743921309029834.

Full text

Abstract:

AbstractModern radio telescopes are extremely sensitive to plasma on the line of sight from a radio source to the antenna. Plasmas in the corona and solar wind produce measurable changes in the radio wave amplitude and phase, and the phase difference between wave fields of opposite circular polarization. Such measurements can be made of radio waves from spacecraft transmitters and extragalactic radio sources, using radio telescopes and spacecraft tracking antennas. Data have been taken at frequencies from about 80 MHz to 8000 MHz. Lower frequencies probe plasma at greater heliocentric distance

APA, Harvard, Vancouver, ISO, and other styles

25

Lee, Jeongwoo, and Stephen M. White. "Microwave Depolarization above Sunspots." Proceedings of the International Astronomical Union 6, S273 (2010): 487–90. http://dx.doi.org/10.1017/s1743921311015857.

Full text

Abstract:

AbstractMicrowave emissions from sunspots are circularly polarized in the sense of rotation (right or left) determined by the polarity (north or south) of coronal magnetic fields. However, they may convert into unpolarized emissions under certain conditions of magnetic field and electron density in the corona, and this phenomenon of depolarization could be used to derive those parameters. We propose another diagnostic use of microwave depolarization based on the fact that an observed depolarization strip actually represents the coronal magnetic polarity inversion line (PIL) at the heights of e

APA, Harvard, Vancouver, ISO, and other styles

26

Tanabe, Toshihiko, Tsumuraya Fumiaki, Naoshi Baba, Manuel Alvarez, Motokazu Noguchi, and Syuzo Isobe. "Optical Polarization Observations of the Solar Corona during the Total Solar Eclipse of 1991 July 11." Publications of the Astronomical Society of Japan 44, no. 5 (1992): 221–26. https://doi.org/10.1093/pasj/44.5.l221.

Full text

Abstract:

Abstract We report here on the results of optical polarization observations of the outer solar corona during the total solar eclipse of 1991 July 11, with specially designed telescopes. The observations were carried out near the summit of Mt. Popocatepetl in Mexico at an altitude of 5250 m to reduce atmospheric-scattered light. Polarization vector maps around the Sun were obtained at wavelengths of 532.5, 596.5, 720.0, and 801.5 nm. Strong polarization was observed in the regions where coronal streamers dominate and is thought to be due to Thomson scattering by free electrons. No excess polari

APA, Harvard, Vancouver, ISO, and other styles

27

Ramesh, R., C. Kathiravan, and E. Ebenezer Chellasamy. "Circular Polarization Observations of Type II Solar Radio Bursts and the Coronal Magnetic Field." Astrophysical Journal 932, no. 1 (2022): 48. http://dx.doi.org/10.3847/1538-4357/ac6f05.

Full text

Abstract:

Abstract It is well known that magnetic field strength (B) in the solar corona can be calculated using the Alfvén Mach number (M A ) and Alfvén speed (v A ) of the magnetohydrodynamic shock waves associated with coronal type II radio bursts. We show that observations of weak circularly polarized emission associated with the harmonic component of the type II bursts provide independent and consistent estimates of B. For the coronal type II burst observed on 2021 October 9, we obtained B ≈1.5 G and ≈1.9 G at a heliocentric distance (r) of ≈1.8 R ⊙, using the above two techniques, respectively.

APA, Harvard, Vancouver, ISO, and other styles

28

Marinucci, A., D. Porquet, F. Tamborra, et al. "A deep X-ray view of the bare AGN Ark 120." Astronomy & Astrophysics 623 (February 25, 2019): A12. http://dx.doi.org/10.1051/0004-6361/201834454.

Full text

Abstract:

Context. The spectral shape of the hard X-ray continuum of Active Galactic Nuclei (AGN) can be ascribed to inverse Compton scattering of optical/UV seed photons from the accretion disc by a hot corona of electrons. This physical process produces a polarization signal which is strongly sensitive to the geometry of the scattering medium (i.e. the hot corona) and of the radiation field. Aims. MoCA (Monte Carlo code for Comptonisation in Astrophysics) is a versatile code which allows for different geometries and configurations to be tested for Compton scattering in compact objects. A single photon

APA, Harvard, Vancouver, ISO, and other styles

29

Qu, Z. Q., L. Chang, G. T. Dun, et al. "Spectropolarimetry of Fraunhofer Lines in Local Upper Solar Atmosphere." Astrophysical Journal 974, no. 1 (2024): 63. http://dx.doi.org/10.3847/1538-4357/ad68f6.

Full text

Abstract:

Abstract Spectropolarimetric results of Fraunhofer lines between 516.3 and 532.6 nm are presented in local upper solar chromosphere and inner corona below a height of about 0.04 solar radius above the solar limb. The data were acquired on 2013 November 3 during a total solar eclipse in Gabon by the prototype Fiber Arrayed Solar Optical Telescope. It is found that the linear polarizations of the Fraunhofer lines in these layers depend strongly on specific spectral lines and positions. A Fraunhofer line at Mg i b 1518.4 nm can have a polarization amplitude up to 0.36% with respect to the continu

APA, Harvard, Vancouver, ISO, and other styles

30

Habbal, Shadia Rifai, and Richard Woo. "Origin of the Solar Wind and Open Coronal Magnetic Structures." Symposium - International Astronomical Union 219 (2004): 587–98. http://dx.doi.org/10.1017/s0074180900182622.

Full text

Abstract:

Identifying the regions of open magnetic structures in the corona, namely regions where field lines expand outwards into interplanetary space, is equivalent to establishing the origin of the solar wind at the Sun. A review of recent studies, based on the comparison of the distribution, as a function of latitude, of density and velocity in the inner corona and in interplanetary space, is presented. It is shown how, at solar minimum, this comparison leads to the unexpected result that the fast solar wind expands indiscriminately from a significant fraction of the solar surface, not limited to po

APA, Harvard, Vancouver, ISO, and other styles

31

Sýkora, J., J. Rybák, and P. Ambrož. "FeXIV Line Emission Polarization of the July 11, 1991 Solar Corona." International Astronomical Union Colloquium 144 (1994): 541–47. http://dx.doi.org/10.1017/s0252921100026002.

Full text

Abstract:

AbstractHigh resolution images, obtained during July 11, 1991 total solar eclipse, allowed us to estimate the degree of solar corona polarization in the light of FeXIV 530.3 nm emission line and in the white light, as well. Very preliminary analysis reveals remarkable differences in the degree of polarization for both sets of data, particularly as for level of polarization and its distribution around the Sun’s limb.

APA, Harvard, Vancouver, ISO, and other styles

32

Kansabanik, Devojyoti, Apurba Bera, Divya Oberoi, and Surajit Mondal. "Tackling the Unique Challenges of Low-frequency Solar Polarimetry with the Square Kilometre Array Low Precursor: Pipeline Implementation." Astrophysical Journal Supplement Series 264, no. 2 (2023): 47. http://dx.doi.org/10.3847/1538-4365/acac79.

Full text

Abstract:

Abstract The dynamics and the structure of the solar corona are determined by its magnetic field. Measuring coronal magnetic fields is, however, extremely hard. The polarization of low-frequency radio emissions has long been recognized as one of the few effective observational probes of magnetic fields in the mid and high corona. However, the extreme intrinsic variability of this emission, the limited ability of most of the available existing instrumentation (until recently) to capture it, and the technical challenges involved have all contributed to its use being severely limited. The high dy

APA, Harvard, Vancouver, ISO, and other styles

33

Fang, Y., P. L. Lamy, and A. Llebaria. "Synthetic Maps of the Brightness and Polarization of the F-Corona." International Astronomical Union Colloquium 126 (1991): 195–98. http://dx.doi.org/10.1017/s0252921100066768.

Full text

Abstract:

AbstractThe Wide-Field Light and Spectrometric Coronograph (LASCO) to be flown on SOHO in 1995 is designed to perform accurate photopolarimetric observations of the solar corona. For simulation purpose but also to have a two-dimensional model of the F-corona, we have realized synthetic maps of its brightness and polarization

APA, Harvard, Vancouver, ISO, and other styles

34

Yang, Huayan, Sijia Lu, Shengkun Wang, et al. "Evolution of the protein corona affects macrophage polarization." International Journal of Biological Macromolecules 191 (November 2021): 192–200. http://dx.doi.org/10.1016/j.ijbiomac.2021.09.081.

Full text

APA, Harvard, Vancouver, ISO, and other styles

35

Hundhausen, A. J., D. G. Sime, and B. C. Low. "Solar Coronal Mass Ejections." Symposium - International Astronomical Union 140 (1990): 16. http://dx.doi.org/10.1017/s0074180900189399.

Full text

Abstract:

In addition to the more or less steady solar wind, the Sun also ejects mass in highly time dependent events taking place in the corona once every few days at solar activity minimum and as often as three times a day at solar activity maximum (Hundhausen 1988, Low 1986). These events involve large scale reconfiguration of the corona with an expulsion of some 1015g of ionized material into interplanetary space. The High Altitude Observatory (HAO) operates a groundbased internally occulted coronagraph at Mauna Loa, Hawaii, with a field of view of the corona from 1.2 to 2.2R⊙ in heliocentric distan

APA, Harvard, Vancouver, ISO, and other styles

36

Long, Xiangyun, Hua Feng, Hong Li, et al. "A Significant Detection of X-ray Polarization in Sco X-1 with PolarLight and Constraints on the Corona Geometry." Astrophysical Journal Letters 924, no. 1 (2022): L13. http://dx.doi.org/10.3847/2041-8213/ac4673.

Full text

Abstract:

Abstract We report the detection of X-ray polarization in the neutron-star low-mass X-ray binary Scorpius (Sco) X-1 with PolarLight. The result is energy-dependent, with a nondetection in 3–4 keV but a 4σ detection in 4–8 keV; it is also flux-dependent in the 4–8 keV band, with a nondetection when the source displays low fluxes but a 5σ detection during high fluxes, in which case we obtain a polarization fraction of 0.043 ± 0.008 and a polarization angle of 52.°6 ± 5.°4. This confirms a previous marginal detection with OSO-8 in the 1970s and marks Sco X-1 as the second astrophysical source wit

APA, Harvard, Vancouver, ISO, and other styles

37

Kuhn, J. R., H. Lin, P. Lamy, S. Koutchmy, and R. N. Smartt. "IR Observations of the K and F Corona During the 1991 Eclipse." Symposium - International Astronomical Union 154 (1994): 185–97. http://dx.doi.org/10.1017/s0074180900124428.

Full text

Abstract:

The availability of relatively large format IR array detectors is incentive for reexamining the classic question of whether or not there are “dust rings” around the sun – a problem for which there are conflicting observational answers. The 1991 eclipse path included a high altitude observatory and provided a potentially ideal opportunity to study the infrared properties and dust content of the corona. Here we report results from an experiment conducted from Mauna Kea using a HgCdTe array detector sensitive to wavelengths between 1-2.5 μm. Surface brightness measurements in the H-band and polar

APA, Harvard, Vancouver, ISO, and other styles

38

Mo, Jianbin, Yun Xu, Xiuxiu Wang, Wei Wei, and Jing Zhao. "Exploiting the protein corona: coating of black phosphorus nanosheets enables macrophage polarization via calcium influx." Nanoscale 12, no. 3 (2020): 1742–48. http://dx.doi.org/10.1039/c9nr08570j.

Full text

APA, Harvard, Vancouver, ISO, and other styles

39

Schad, Thomas A., Sarah A. Jaeggli, and Gabriel I. Dima. "Thomson Scattering above Solar Active Regions and an Ad Hoc Polarization Correction Method for the Emissive Corona." Astrophysical Journal 933, no. 1 (2022): 53. http://dx.doi.org/10.3847/1538-4357/ac713c.

Full text

Abstract:

Abstract Thomson-scattered photospheric light is the dominant constituent of the lower solar corona’s spectral continuum viewed off-limb at optical wavelengths. Known as the K-corona, it is also linearly polarized. We investigate the possibility of using the a priori polarized characteristics of the K-corona, together with polarized emission lines, to measure and correct instrument-induced polarized crosstalk. First we derive the Stokes parameters of the Thomson scattering of unpolarized light in an irreducible spherical tensor formalism. This allows forward synthesis of the Thomson-scattered

APA, Harvard, Vancouver, ISO, and other styles

40

Rawat, Divya, Akash Garg, and Mariano Méndez. "Detection of X-Ray Polarized Emission and Accretion-disk Winds with IXPE and NICER in the Black Hole X-Ray Binary 4U 1630−47." Astrophysical Journal Letters 949, no. 2 (2023): L43. http://dx.doi.org/10.3847/2041-8213/acd77b.

Full text

Abstract:

Abstract We detect a high level of polarization in the X-ray emission of the black hole binary 4U 1630–47 in an observation with the Imaging X-ray Polarimetry Explorer. The 2–8 keV polarization degree is 8% at a position angle of 18°, with the polarization degree increasing significantly with energy, from ∼6% at ∼2 keV to ∼11% at ∼8 keV. The continuum emission in the spectrum of simultaneous observations with the Neutron Star Interior Composition Explorer (NICER) is well described with only a thermal disk spectrum, with stringent upper limits to any Comptonized emission from the corona. Togeth

APA, Harvard, Vancouver, ISO, and other styles

41

Qu, Z. Q., L. Chang, G. T. Dun, et al. "Complexity of the Upper Solar Atmosphere Revealed from Spectropolarimetry during a Solar Eclipse." Astrophysical Journal 940, no. 2 (2022): 150. http://dx.doi.org/10.3847/1538-4357/ac9af4.

Full text

Abstract:

Abstract We analyze linear polarimetric spectrum data of solar emission lines with different formation temperatures in a visible light band from 516.3–532.6 nm, obtained during the 2013 Gabon solar eclipse using the prototype Fiber Arrayed Solar Optical Telescope. Complexities are found from the chromosphere through the transition zone to the corona at the spatial resolution limit of 2″ and temporal resolution of seconds. The observations show irregular spatial and spectral variations in linear polarization amplitudes, directions, and profile shapes. Within the observational band, spectral lin

APA, Harvard, Vancouver, ISO, and other styles

42

Banerjee, S., W. Du, U. Sundar, and K. A. Cook-Chennault. "Piezoelectric and Dielectric Characterization of MWCNT-Based Nanocomposite Flexible Films." Journal of Nanomaterials 2018 (September 30, 2018): 1–15. http://dx.doi.org/10.1155/2018/6939621.

Full text

Abstract:

PZT-epoxy-multiwalled carbon nanotube (MWCNT) flexible thick film actuators were fabricated using a sol-gel and spin coat and deposition process. Films were characterized in terms of their piezoelectric and dielectric properties as a function of MWCNT volume fraction and polarization process. Correlations between surface treatment of the MWCNTs and composite performance were made. The surface morphology and filler distribution were observed with the aid of SEM and TEM images. The volume fraction of PZT was held constant at 30%, and the volume fraction of MWCNTs varied from 1% to 10%. Two forms

APA, Harvard, Vancouver, ISO, and other styles

43

Heinzel, Petr, Sonja Jejčič, Jiří Štěpán, et al. "First Metis Detection of the Helium D₃ Line Polarization in a Large Eruptive Prominence." Astrophysical Journal Letters 957, no. 1 (2023): L10. http://dx.doi.org/10.3847/2041-8213/acff62.

Full text

Abstract:

Abstract Metis on board Solar Orbiter is the space coronagraph developed by an Italian–German–Czech consortium. It is capable of observing solar corona and various coronal structures in the visible-light (VL) and UV (hydrogen Lyα) channels simultaneously for the first time. Here we present observations of a large eruptive prominence on 2021 April 25–26, in the VL, taken during the mission cruise phase, and demonstrate that apart from the broadband continuum emission, which is due to the Thomson scattering on prominence electrons, we detect a significant radiation in the neutral-helium D3 line

APA, Harvard, Vancouver, ISO, and other styles

44

Kapanadze, N. G., V. I. Kulijanishvili, and Ahmed A. Hady. "Polarization properties of the June 21, 2001 solar corona." Proceedings of the International Astronomical Union 2, S233 (2006): 255. http://dx.doi.org/10.1017/s1743921306001979.

Full text

APA, Harvard, Vancouver, ISO, and other styles

45

Jin, Xiaojia, Matthias Kuehne, Xun Gong, Amandine Ucko, and Michael S. Strano. "Polarization Resolved Fluorescence Detection of Carbon Nanotube Corona Phases." ECS Meeting Abstracts MA2023-01, no. 10 (2023): 1219. http://dx.doi.org/10.1149/ma2023-01101219mtgabs.

Full text

Abstract:

Circular dichroism measures how chiral particles absorb right- and left- circularly polarized light differently to distinguish pairs of enantiomers. It can also elucidate differential photoabsorption of chiral fluorescent species via their emissions. However, this method has generally been restricted to bulk samples. Hence, these methods conceal information on the specific chiroptical response of a single particle. Furthermore, circular dichroism has been restricted in time- resolution as well as spectral range. In this work, we observed fluorescence detected circular dichroism (FDCD) of indiv

APA, Harvard, Vancouver, ISO, and other styles

46

El Mouden, Mahmoud, Fouad Belhora, Yassine Tabbai, Abdelowahed Hajjaji, and Abdessamad El Ballouti. "Improvement of the magneto-electric effect of composites loaded with different magnetic particles for current sensor applications." European Physical Journal Applied Physics 87, no. 1 (2019): 10901. http://dx.doi.org/10.1051/epjap/2019190097.

Full text

Abstract:

This article proposes a methodology to improve the magneto-electric effect of a poly(vinylidene fluoride-co-trifluoroethylene) P(VDF-TrFe) copolymer, doped with nanoparticles of nickel (Ni) and nickel iron (NiFe). The preparation of the composite films were achieved through the solvent casting approach. First, P(VDF-TrFe) powders and (Ni and NiFe) nanoparticles are dispersed in dimethyl formamide (DMF) as a solvent to form a homogeneous solution. Then, the solution obtained is deposited on a flexible substrate by a spin coating process. After that, the NiFe doped composites are corona polarize

APA, Harvard, Vancouver, ISO, and other styles

47

Poutanen, Juri. "Frequency-Dependent Polarization in Comptonization Models for AGN." Symposium - International Astronomical Union 159 (1994): 472. http://dx.doi.org/10.1017/s007418090017651x.

Full text

Abstract:

The angular distribution and the polarization of radiation as a function of the angle and frequency for the two-phase model of accretion disks in AGN are found. The results depend strongly on the temperature of the hot corona.

APA, Harvard, Vancouver, ISO, and other styles

48

Gerasimov D. I., Kuryndin I. S., Lavrentyev V. K., Volgina E. A., Temnov D. E., and Elyashevich G. K. "Structure formation and depolarization relaxation processes in porous piezoactive polyvinylidene fluoride films." Physics of the Solid State 64, no. 10 (2022): 1432. http://dx.doi.org/10.21883/pss.2022.10.54232.389.

Full text

Abstract:

Piezoactive porous polyvinylidene fluoride films prepared in the process based on melt extrusion with subsequent isometric annealing, uniaxial extension and thermal fixation have been studied. It was shown that two competing orientation processes -polymorphous transition of non-polar α-phase into polar piezoactive β-phase and formation of porous structure - occur during the uniaxial extension of annealed films. It has been established that orientation degree of extruded films is the key factor determining the efficiency of both processes. Thermally stimulated depolarization method was used to

APA, Harvard, Vancouver, ISO, and other styles

49

Zhao, Qing-Chang, Hong Li, Lian Tao, and Hua Feng. "The Discovery of Rapid Polarization Angle Variation during the 2022 Outburst of XTE J1701-462." Astrophysical Journal 982, no. 2 (2025): 105. https://doi.org/10.3847/1538-4357/adb8cf.

Full text

Abstract:

Abstract The geometry of the Comptonization corona in neutron star low-mass X-ray binaries is still unclear. We conducted time-resolved polarimetric analysis of the archival observations of XTE J1701–462 obtained with the Imaging X-ray Polarimeter Explorer during its 2022 outburst and found that the polarization angle (PA) varied significantly with time when the source was in the normal branch, with 67∘ ± 8∘ in the first epoch, −34∘ ± 8∘ in the second, and −58∘ ± 8∘ in the third, last epoch. Meanwhile, the polarization degree remained constant at around 2%, above the minimum detectable polariz

APA, Harvard, Vancouver, ISO, and other styles

50

Duckenfield, T. J., D. B. Jess, R. J. Morton, and S. Jafarzadeh. "Determining the Polarization of a Coronal Standing Kink Oscillation Using Spectral Imaging Techniques with CoMP." Astrophysical Journal 982, no. 2 (2025): 202. https://doi.org/10.3847/1538-4357/adb8d6.

Full text

Abstract:

Abstract Coronal oscillations offer insight into energy transport and driving in the solar atmosphere. Knowing its polarization state helps constrain a wave’s displacement and velocity amplitude, improving estimates of wave energy flux and deposition rate. We demonstrate a method to combine imaging and spectral data to infer the polarization of a coronal loop’s standing kink wave, without the need for multiple instruments or multiple lines of sight. We use the unique capabilities of the Coronal Multi-channel Polarimeter (CoMP) to observe the standing kink mode of an off-limb coronal loop pertu

APA, Harvard, Vancouver, ISO, and other styles

We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!