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Related papers: An Unfolding Method for X-ray Spectro-Polarimetry

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Solar flare electron acceleration is an extremely efficient process, but the method of acceleration is not well constrained. Two of the essential diagnostics: electron anisotropy (velocity angle to the guiding magnetic field) and the high…

Solar and Stellar Astrophysics · Physics 2020-12-21 Natasha L. S. Jeffrey , Pascal Saint-Hilaire , Eduard P. Kontar

Magnetars are believed to host the strongest magnetic fields in the present universe ($B\gtrsim10^{14}$ G) and the study of their persistent emission in the X-ray band offers an unprecendented opportunity to gain insight into physical…

High Energy Astrophysical Phenomena · Physics 2020-03-03 Roberto Taverna , Roberto Turolla , Valery Suleimanov , Alexander Y. Potekhin , Silvia Zane

In this chapter we present a brief summary of methods, instruments and calibration techniques used in modern astronomical polarimetry in the optical wavelengths. We describe the properties of various polarization devices and detectors used…

Instrumentation and Methods for Astrophysics · Physics 2019-08-29 Andrei Berdyugin , Vilppu Piirola , Juri Poutanen

We present a versatile method for full-field, X-ray scattering tensor tomography that is based on energy conservation and is applicable to data obtained using different wavefront modulators. Using this algorithm, we pave the way for…

X-rays are particularly suited to probe the physics of extreme objects. However, despite the enormous improvements of X-ray Astronomy in imaging, spectroscopy and timing, polarimetry remains largely unexplored. We propose the photoelectric…

Since the birth of X-ray astronomy, spectral, spatial and timing observation improved dramatically, procuring a wealth of information on the majority of the classes of the celestial sources. Polarimetry, instead, remained basically…

The INFN and INAF Italian research institutes developed a space-borne X-Ray polarimetry experiment based on a X-Ray telescope, focussing the radiation on a Gas Pixel Detector (GPD). The instrument obtains the polarization angle of the…

X-ray polarimetry has the potential to make key-contributions to our understanding of galactic compact objects like binary black hole systems and neutron stars, and extragalactic objects like active galactic nuclei, blazars, and Gamma Ray…

Instrumentation and Methods for Astrophysics · Physics 2015-05-27 Henric Krawczynski

This paper discusses the latest progress in the development of GRAPE (Gamma-Ray Polarimeter Experiment), a hard X-ray Compton Polarimeter. The purpose of GRAPE is to measure the polarization of hard X-rays in the 50-300 keV energy range. We…

Astrophysics · Physics 2017-08-23 J. S. Legere , P. Bloser , J. R. Macri , M. L. McConnell , T. Narita , J. M. Ryan

Slitless (or wide field) imaging spectroscopy provides simultaneous imaging and spectral information from a wide field of view, which allows for rapid spectroscopic data collection of extended sources. Depending on the size of the extended…

Solar and Stellar Astrophysics · Physics 2024-07-16 P. S. Athiray , Arthur Hochedez , Amy R Winebarger , Dyana Beabout

We present a fast method for estimating the cosmic microwave background polarization power spectra using unbiased estimates of heuristically-weighted correlation functions. This extends the O(N_pix^(3/2)) method of Szapudi et al. (2001) to…

Astrophysics · Physics 2009-11-07 Gayoung Chon , Anthony Challinor , Simon Prunet , Eric Hivon , Istvan Szapudi

X-radiation from energetic electrons is the prime diagnostic of flare-accelerated electrons. The observed X-ray flux (and polarization state) is fundamentally a convolution of the cross-section for the hard X-ray emission process(es) in…

The key to photoelectric X-ray polarimetry is the determination of the emission direction of photoelectrons. Because of the low mass of an electron, the ionisation trajectory is not straight and the useful information needed for polarimetry…

Instrumentation and Detectors · Physics 2021-09-03 Tenglin Li , Ming Zeng , Hua Feng , Jirong Cang , Hong Li , Heng Zhang , Zhi Zeng , Jianping Cheng , Hao Ma , Yinong Liu

X-rays astrophysical sources have been almost exclusively characterized through imaging, spectroscopy and timing analysis. Nevertheless, more observational parameters are needed because some radiation mechanisms present in neutrons stars or…

Instrumentation and Methods for Astrophysics · Physics 2015-05-06 S. Antier , O. Limousin , P. Ferrando

Current mm/submm interferometers, like the Atacama Large mm/submm Array (ALMA), use receivers that register the sky signal in a linear polarization basis. In the case of observations performed in full-polarization mode (where the…

Instrumentation and Methods for Astrophysics · Physics 2016-09-21 I. Marti-Vidal , W. H. T. Vlemmings , S. Muller

Polarized X-rays allow for imaging birefringent or dichroic properties of materials with nanometric resolution. To disentangle these properties from the electronic density, either a polarization analyzer or several measurements with…

We study the impact of gas motions on the polarization of bright X-ray emission lines from the hot intercluster medium (ICM). The polarization naturally arises from resonant scattering of emission lines owing to a quadrupole component in…

High Energy Astrophysical Phenomena · Physics 2015-05-14 I. V. Zhuravleva , E. M. Churazov , S. Yu. Sazonov , R. A. Sunyaev , W. Forman , K. Dolag

We report on Monte Carlo studies of the hard X-ray polarimeter X-Calibur. The polarimeter will be used in the focal plane of a grazing incidence hard X-ray telescope. It combines a low-Z Compton scatterer with a high-Z Cadmium Zinc…

Instrumentation and Methods for Astrophysics · Physics 2011-01-04 Qingzhen Guo , Alfred Garson , Matthias Beilicke , Jerrad Martin , Kuen Lee , Henric Krawczynski

In this paper, we introduce an iterative speckle filtering method for polarimetric SAR (PolSAR) images based on the bilateral filter. To locally adapt to the spatial structure of images, this filter relies on pixel similarities in both…

Computer Vision and Pattern Recognition · Computer Science 2013-11-04 Olivier D'Hondt , Stéphane Guillaso , Olaf Hellwich

Super-Eddington accretion onto compact objects is expected to produce optically thick outflows with a funnel-shaped cavity that may collimate the emission. At inclinations higher than the grazing angle of the funnel, the central source is…

High Energy Astrophysical Phenomena · Physics 2026-05-29 Varpu Ahlberg , Alexandra Veledina , Eugene Churazov , Ildar Khabibullin
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