Observational Aspects of Hard X-ray Polarimetry
Creators: name: Chattopadhyay, Tanmoy
Publisher: name: Zenodo
Year: 2016
Subjects: X-ray polarimetry
Compton scattering
Hard X-ray telescopes
Geant−4 simulation
Instrumentation
Astrosat
Cadmium Zinc Telluride Imager (CZTI)
Response matrix
Cygnus X-1
Crab pulsar

description: Sensitive polarization measurements in X-ray may address a wealth of astrophysical phenomena, which so far remain beyond our understanding through available X-ray spectroscopic, imaging, and timing studies. Though scientific potential of X-ray polarimetry was realized long ago, there has not been any significant advancement in this field for the last four decades since the birth of X-ray astronomy. The only successful polarization measurement in X-rays dates back to 1976, when a Bragg polarimeter onboard OSO-8 measured polarization of Crab nebula. Primary reason behind the lack in progress is its extreme photon hungry nature, which results in poor sensitivity of the polarimeters. Recently, in the last decade or so, with the advancement in detection technology, X-ray polarimetry may see a significant progress in near future, especially in soft X-rays with the invention of photoelectron tracking polarimeters. Though photoelectric polarimeters are expected to provide sensitive polarization measurements of celestial X-ray sources, they are sensitive only in soft X-rays, where the radiation from the sources is dominated by thermal radiation and therefore expected to be less polarized. On the other hand, in hard X-rays, sources are ex-pected to be highly polarized due to the dominance of nonthermal emission over its thermal counterpart. Moreover, polarization measurements in hard X-rays promises to address few interesting scientific issues regarding geometry of corona for black hole sources, emission mechanism responsible for the higher energy peak in the blazars, accretion geometry close to the magnetic poles in accreting neutron star systems and acceleration mechanism in solar flares. Compton polarimeters provide better sensitivity than photoelectric polarimeters in hard X-rays with a broad energy band of operation. Recently, with the development of hard X-ray focusing optics e.g. NuSTAR, Astro-H, it is now possible to conceive Compton polarimeters at the focal plane of such hard X-ray telescopes, which may provide sensitive polarization measurements due to flux concentration in hard X-rays with a very low background. On the other hand, such a configuration ensures implementation of an optimized geometry close to an ideal one for the Compton polarimeters. In this context, we initiated the development of a focal plane Compton polarimeter, consisting of a plastic scatterer surrounded by a cylindrical array of CsI(Tl) scintillators. Geant−4 simulations of the planned configuration estimates 1% MDP for a 100 mCrab source in 1 million seconds of exposure. Sensitivity of the instrument is found to be critically dependent on the lower energy detection limit of the plastic scatterer; lower the threshold, better is the sensitivity. In the actual experiment, the plastic is readout by a photomultiplier tube procured from Saint-Gobain. We carried out extensive experiments to characterize the plastic especially for lower energy depositions. The CsI(Tl) scintillators are readout by Si photomultipliers (SiPM). SiPMs are small in size and robust and therefore provide the compactness necessary for the designing of focal plane detectors. Each of the CsI(Tl)-SiPM systems was characterized precisely to estimate their energy threshold and detection probability along the length of the scintillators away from SiPM. Finally, we integrated the Compton polarimeter and tested its response to polarized and unpolarized radiation and compared the experimental results with Geant−4 simulation. Despite the growing realization of the scientific values of X-ray polarimetry and the efforts in developing sensitive X-ray polarimeters, there has not been a single dedicated X-ray polarimetry mission planned in near future. In this scenario, it is equally important to attempt polarization measurements from the existing or planned instruments which are not meant for X-ray polarization measurements but could be sensitive to it. There have been several attempts in past in retrieving polarization information from few of such spectroscopic instruments like RHESSI, INTEGRAL-IBIS, INTEGRAL-SPI. Cadmium Zinc Telluride Imager (CZTI) onboard Astrosat, India’s first astronomical mission, is one of such instruments which is expected to provide sensitive polarization measurements for bright X-ray sources. CZTI consists of 64 CZT detector modules, each of which is 5 mm thick and 4 cm × 4 cm in size. Each CZT module is subdivided into 256 pixels with pixel pitch of 2.5 mm. Due to its pixelation nature and significant Compton scattering efficiency at energies beyond 100 keV, CZTI can work as a sensitive Compton polarimeter in hard X-rays. Detailed Geant−4 simulations and polarization experiments with the flight configuration of CZTI show that CZTI will have significant polarization measurement capability for bright sources in hard X-rays. CZTI is primarily a spectroscopic instrument with coded mask imaging. To properly utilize the spectroscopic capabilities of CZT detectors, it is important to generate accurate response matrix for CZTI, which in turn requires precise modelling of the CZT lines shapes for monoenergetic X-ray interaction. CZT detectors show an extended lower energy tail of an otherwise Gaussian line shape due to low mobility and lifetime of the charge carriers. On the other hand, interpixel charge sharing may also contribute to the lower energy tail making the line shape more complicated. We have developed a model to predict the line shapes from CZTI modules taking into account the mobility and lifetime of the charge carriers and charge sharing fractions. The model predicts the line shape quite well and can be used to generate pixel-wise response matrix for CZTI.
description: 236 pages
description: {"references": ["[1] M. C. Weisskopf, G. G. Cohen, H. L. Kestenbaum, K. S. Long, R. Novick,", "and R. S. Wolff, Measurement of the X-ray polarization of the Crab Nebula,", "Astrophysical Journal Letter 208, L125\u2013L128 (1976).", "[2] M. C. Weisskopf, E. H. Silver, H. L. Kestenbaum, K. S. Long, and R. Novick,", "A precision measurement of the X-ray polarization of the Crab Nebula with-", "out pulsar contamination, Astrophysical Journal Letter 220, L117\u2013L121", "(1978).", "[3] J. R. Angel, R. Novick, P. vanden Bout, and R. Wolff, Search for X-Ray", "Polarization in Sco X-1, Physical Review Letters 22, 861\u2013865 (1969).", "[4] R. S. Wolff, J. R. P. Angel, R. Novick, and P. vanden Bout, Search for Po-", "larization in the X-Ray Emission of the Crab Nebula, Astrophysical Journal", "Letter 160, L21 (1970).", "[5] R. Novick, M. C. Weisskopf, R. Berthelsdorf, R. Linke, and R. S. Wolff,", "Detection of X-Ray Polarization of the Crab Nebula, Astrophysical Journal", "Letter 174, L1 (1972).", "[6] R. E. Griffiths, M. J. Ricketts, and B. A. Cooke, Observations of the X-ray", "nova A0620-00 with the Ariel V crystal spectrometer/polarimeter, MNRAS", "177, 429\u2013440 (1976).", "[7] R. A. Gowen, B. A. Cooke, R. E. Griffiths, and M. J. Ricketts, An upper", "limit to the linear X-ray polarization of SCO X-1, MNRAS 179, 303\u2013310", "(1977).", "[8] E. H. Silver, M. C. Weisskopf, H. L. Kestenbaum, K. S. Long, R. Novick,", "and R. S. Wolff, The first search for X-ray polarization in the Centaurus", "X-3 and Hercules X-1 pulsars, Astrophysical Journal 232, 248\u2013254 (1979).", "[9] J. P. Hughes, K. S. Long, and R. Novick, A search for X-ray polarization", "in cosmic X-ray sources, Astrophysical Journal 280, 255\u2013258 (1984).", "[10] J. R. P. Angel and M. C. Weisskopf, Use of Highly Reflecting Crystals", "for Spectroscopy and Polarimetry in X-Ray Astronomy, The Astronomical", "Journal 75, 231 (1970).", "[11] H. Tsunemi, K. Hayashida, K. Tamura, S. Nomoto, M. Wada, A. Hirano,", "and E. Miyata, Detection of X-ray polarization with a charge coupled device,", "Nuclear Instruments and Methods in Physics Research A 321, 629\u2013631", "(1992).", "[12] R. F. Elsner, B. D. Ramsey, S. L. O\u2019dell, M. Sulkanen, A. F. Tennant,", "M. C. Weisskopf, S. Gunji, T. Minamitani, R. A. Austin, J. Kolodziejczak,", "D. Swartz, G. Garmire, P. Meszaros, and G. G. Pavlov, The X-ray Po-", "larimeter Experiment (XPE), in \u201cAmerican Astronomical Society Meeting", "Abstracts #190,\u201d , vol. 29 of Bulletin of the American Astronomical Society", "(1997), vol. 29 of Bulletin of the American Astronomical Society, p. 790.", "[13] H. L. Marshall, S. S. Murray, J. H. Chappell, H. W. Schnopper, E. H.", "Silver, and M. C. Weisskopf, Realistic, inexpensive, soft x-ray polarimeter", "and the potential scientific return, in \u201cPolarimetry in Astronomy,\u201d , vol.", "4843 of Society of Photo-Optical Instrumentation Engineers (SPIE) Con-", "ference Series, S. Fineschi, ed. (2003), vol. 4843 of Society of Photo-Optical", "Instrumentation Engineers (SPIE) Conference Series, pp. 360\u2013371.", "[14] P. E. Kaaret, J. Schwartz, P. Soffitta, J. Dwyer, P. S. Shaw, S. Hanany,", "R. Novick, R. Sunyaev, I. Y. Lapshov, E. H. Silver, K. P. Ziock, M. C.", "Weisskopf, R. F. Elsner, B. D. Ramsey, E. Costa, A. Rubini, M. Feroci,", "L. Piro, G. Manzo, S. Giarrusso, A. E. Santangelo, L. Scarsi, G. C. Perola,", "E. Massaro, and G. Matt, Status of the stellar x-ray polarimeter for the", "Spectrum-X-Gamma mission, in \u201cX-Ray and Ultraviolet Polarimetry,\u201d ,", "vol. 2010 of Society of Photo-Optical Instrumentation Engineers (SPIE)", "Conference Series, S. Fineschi, ed. (1994), vol. 2010 of Society of Photo-", "Optical Instrumentation Engineers (SPIE) Conference Series, pp. 22\u201327.", "[15] P. Laurent, J. Rodriguez, J. Wilms, M. Cadolle Bel, K. Pottschmidt, and", "V. Grinberg, Polarized Gamma-Ray Emission from the Galactic Black Hole", "Cygnus X-1, Science 332, 438\u2013 (2011).", "[16] E. Jourdain, J. P. Roques, M. Chauvin, and D. J. Clark, Separation of Two", "Contributions to the High Energy Emission of Cygnus X-1: Polarization", "Measurements with INTEGRAL SPI, Astrophysical Journal 761, 27 (2012).", "[17] M. Forot, P. Laurent, I. A. Grenier, C. Gouiff`s, and F. Lebrun, Polariza-", "tion of the Crab Pulsar and Nebula as Observed by the INTEGRAL/IBIS", "Telescope, Astrophysical Journal Letter 688, L29\u2013L32 (2008).", "[18] A. J. Dean, D. J. Clark, J. B. Stephen, V. A. McBride, L. Bassani, A. Baz-", "zano, A. J. Bird, A. B. Hill, S. E. Shaw, and P. Ubertini, Polarized Gamma-", "Ray Emission from the Crab, Science 321, 1183\u2013 (2008).", "[19] F. Lei, A. J. Dean, and G. L. Hills, Compton Polarimetry in Gamma-Ray", "Astronomy, Space Science Reviews 82, 309\u2013388 (1997).", "[20] P. Soffitta, X-ray polarimetry an almost new frontier for X-ray astronomy,", "in \u201cItal. Phys. Soc. Conf. Ser. 57: Frontier Objects in Astrophysics and", "Particle Physics,\u201d , F. Giovannelli and G. Mannocchi, eds. (1997), p. 561.", "[21] H. Krawczynski, A. Garson, Q. Guo, M. G. Baring, P. Ghosh, M. Beilicke,", "and K. Lee, Scientific prospects for hard X-ray polarimetry, Astroparticle", "Physics 34, 550\u2013567 (2011).", "[22] M. Dov\u02c7iak, F. Muleri, R. W. Goosmann, V. Karas, and G. Matt, Thermal", "disc emission from a rotating black hole: X-ray polarization signatures,", "MNRAS 391, 32\u201338 (2008).", "[23] J. D. Schnittman and J. H. Krolik, X-ray Polarization from Accreting Black", "Holes: The Thermal State, 701, 1175\u20131187 (2009).", "[24] J. D. Schnittman and J. H. Krolik, X-ray Polarization from Accreting Black", "Holes: Coronal Emission, Astrophysical Journal 712, 908\u2013924 (2010).", "[25] S. V. Vadawale, A. R. Rao, and S. K. Chakrabarti, Spectral differences", "between the radio-loud and radio-quiet low-hard states of GRS 1915+105:", "Possible detection of synchrotron radiation in X-rays, Astronomy &amp; Astro-", "physics 372, 793\u2013802 (2001).", "[26] S. V. Vadawale, A. R. Rao, S. Naik, J. S. Yadav, C. H. Ishwara-Chandra,", "A. Pramesh Rao, and G. G. Pooley, On the Origin of the Various Types of", "Radio Emission in GRS 1915+105, Astrophysical Journal 597, 1023\u20131035", "(2003).", "[27] S. Markoff, H. Falcke, and R. Fender, A jet model for the broadband spec-", "trum of XTE J1118+480. Synchrotron emission from radio to X-rays in the", "Low/Hard spectral state, Astronomy &amp; Astrophysics 372, L25\u2013L28 (2001).", "[28] A. A. Zdziarski, P. Pjanka, M. Sikora, and L. Stawarz, Jet contributions", "to the broad-band spectrum of Cyg X-1 in the hard state, MNRAS 442,", "3243\u20133255 (2014).", "[29] G. E. Romero, F. L. Vieyro, and S. Chaty, Coronal origin of the polarization", "of the high-energy emission of Cygnus X-1, Astronomy &amp; Astrophysics 562,", "L7 (2014).", "[30] R. W. Goosmann and G. Matt, Spotting the misaligned outflows in NGC", "1068 using X-ray polarimetry, MNRAS 415, 3119\u20133128 (2011).", "[31] P. Uttley, E. M. Cackett, A. C. Fabian, E. Kara, and D. R. Wilkins, X-ray", "reverberation around accreting black holes, 22, 72 (2014).", "[32] A. Celotti and G. Matt, Polarization Properties of Synchrotron Self-", "Compton Emission, MNRAS 268, 451 (1994).", "[33] A. L. McNamara, Z. Kuncic, and K. Wu, X-ray polarization in relativistic", "jets, MNRAS 395, 1507\u20131514 (2009).", "[34] H. Zhang and M. B \u0308ttcher, X-Ray and Gamma-Ray Polarization in Lep-", "o", "tonic and Hadronic Jet Models of Blazars, Astrophysical Journal 774, 18", "(2013).", "[35] M. C. Weisskopf, R. F. Elsner, D. Hanna, V. M. Kaspi, S. L. O\u2019Dell, G. G.", "Pavlov, and B. D. Ramsey, The prospects for X-ray polarimetry and its", "potential use for understanding neutron stars, ArXiv Astrophysics e-prints", "(2006).", "[36] J. K. Daugherty and A. K. Harding, Electromagnetic cascades in pulsars,", "Astrophysical Journal 252, 337\u2013347 (1982).", "[37] K. S. Cheng, M. Ruderman, and L. Zhang, A Three-dimensional Outer", "Magnetospheric Gap Model for Gamma-Ray Pulsars: Geometry, Pair Pro-", "duction, Emission Morphologies, and Phase-resolved Spectra, Astrophysical", "Journal 537, 964\u2013976 (2000).", "[38] J. Dyks and B. Rudak, Two-Pole Caustic Model for High-Energy Light", "Curves of Pulsars, Astrophysical Journal 598, 1201\u20131206 (2003).", "[39] F. G. Smith, D. H. P. Jones, J. S. B. Dick, and C. D. Pike, The optical", "polarization of the Crab Pulsar, MNRAS 233, 305\u2013319 (1988).", "[40] R. W. Romani, A. J. Miller, B. Cabrera, S. W. Nam, and J. M. Marti-", "nis, Phase-resolved Crab Studies with a Cryogenic Transition-Edge Sensor", "Spectrophotometer, Astrophysical Journal 563, 221\u2013228 (2001).", "[41] R. C. Duncan and C. Thompson, Formation of very strongly magnetized", "neutron stars - Implications for gamma-ray bursts, Astrophysical Journal", "Letter 392, L9\u2013L13 (1992).", "[42] P. Meszaros, R. Novick, A. Szentgyorgyi, G. A. Chanan, and M. C. Weis-", "skopf, Astrophysical implications and observational prospects of X-ray po-", "larimetry, Astrophysical Journal 324, 1056\u20131067 (1988).", "[43] K. Viironen and J. Poutanen, Light curves and polarization of accretion-", "and nuclear-powered millisecond pulsars, Astronomy &amp; Astrophysics 426,", "985\u2013997 (2004).", "[44] S. Y. Sazonov and R. A. Sunyaev, Scattering in the inner accretion disk and", "the waveforms and polarization of millisecond flux oscillations in LMXBs,", "Astronomy &amp; Astrophysics 373, 241\u2013250 (2001).", "[45] K. Toma, T. Sakamoto, B. Zhang, J. E. Hill, M. L. McConnell, P. F. Bloser,", "R. Yamazaki, K. Ioka, and T. Nakamura, Statistical Properties of Gamma-", "Ray Burst Polarization, Astrophysical Journal 698, 1042\u20131053 (2009).", "[46] M. Lyutikov, V. I. Pariev, and R. D. Blandford, Polarization of Prompt", "Gamma-Ray Burst Emission: Evidence for Electromagnetically Dominated", "Outflow, Astrophysical Journal 597, 998\u20131009 (2003).", "[47] M. Lyutikov and R. Blandford, Gamma Ray Bursts as Electromagnetic", "Outflows, ArXiv:0312347 (2003).", "[48] A. G. Emslie and J. C. Brown, The polarization and directivity of solar-flare", "hard X-ray bremsstrahlung from a thermal source, Astrophysical Journal", "237, 1015\u20131023 (1980).", "[49] N. L. S. Jeffrey and E. P. Kontar, Spatially resolved hard X-ray polarization", "in solar flares: effects of Compton scattering and bremsstrahlung, Astron-", "omy &amp; Astrophysics 536, A93 (2011).", "[50] V. V. Zharkova, A. A. Kuznetsov, and T. V. Siversky, Diagnostics of ener-", "getic electrons with anisotropic distributions in solar flares. I. Hard X-rays", "bremsstrahlung emission, Astronomy &amp; Astrophysics 512, A8 (2010).", "[51] P. Kaaret, X-Ray Polarimetry, arXiv:1408.5899 (2014).", "[52] W. Heitler, Quantum theory of radiation, in \u201cInternational Series of Mono-", "graphs on Physics, Oxford: Clarendon, 1954, 3rd ed.\u201d, (1954).", "[53] X. Llopart, R. Ballabriga, M. Campbell, L. Tlustos, and W. Wong, Timepix,", "a 65k programmable pixel readout chip for arrival time, energy and/or pho-", "ton counting measurements, Nuclear Instruments and Methods in Physics", "Research A 581, 485\u2013494 (2007).", "[54] T. Michel and J. Durst, Evaluation of a hybrid photon counting pixel de-", "tector for x-ray polarimetry, Nuclear Instruments and Methods in Physics", "Research Section A: Accelerators, Spectrometers, Detectors and Associated", "Equipment 594, 188 \u2013 195 (2008).", "[55] F. Sauli, GEM: A new concept for electron amplification in gas detectors,", "Nuclear Instruments and Methods in Physics Research A 386, 531\u2013534", "(1997).", "[56] E. Costa, P. Soffitta, R. Bellazzini, A. Brez, N. Lumb, and G. Spandre,", "An efficient photoelectric X-ray polarimeter for the study of black holes and", "neutron stars, Nature 411, 662\u2013665 (2001).", "[57] R. Bellazzini, F. Angelini, L. Baldini, F. Bitti, A. Brez, F. Cavalca, M. Del", "Prete, M. Kuss, L. Latronico, N. Omodei, M. Pinchera, M. M. Massai,", "M. Minuti, M. Razzano, C. Sgro, G. Spandre, A. Tenze, E. Costa, and", "P. Soffitta, Gas pixel detectors for X-ray polarimetry applications, Nuclear", "Instruments and Methods in Physics Research A 560, 425\u2013434 (2006).", "[58] R. Bellazzini, G. Spandre, M. Minuti, L. Baldini, A. Brez, L. Latronico,", "N. Omodei, M. Razzano, M. M. Massai, M. Pesce-Rollins, C. Sgr \u0301, E. Costa,", "o", "P. Soffitta, H. Sipila, and E. Lempinen, A sealed Gas Pixel Detector for X-", "ray astronomy, Nuclear Instruments and Methods in Physics Research A", "579, 853\u2013858 (2007).", "[59] J. K. Black, R. G. Baker, P. Deines-Jones, J. E. Hill, and K. Jahoda, X-ray", "polarimetry with a micropattern TPC, Nuclear Instruments and Methods", "in Physics Research A 581, 755\u2013760 (2007).", "[60] J. R. Toraskar, Focusing crystal polarimeter designed for X-ray polarimetry", "- Construction and performance, Applied Optics 14, 1727\u20131735 (1975).", "[61] R. Novick, Stellar and Solar X-Ray Polarimetry, Space Science Reviews", "18, 389\u2013408 (1975).", "[62] E. Silver, J. Holley, K. Ziock, R. Novick, P. Kaaret, M. Weisskopf, and", "R. Elsner, Bragg crystal polarimeters, Optical Engineering 29, 759\u2013766", "(1990).", "[63] H. W. Schnopper and K. Kalata, Polarimeter for Celestial X Rays, 74, 854", "(1969).", "[64] E. Costa, R. Bellazzini, G. Tagliaferri, G. Matt, A. Argan, P. Attin`, L. Bal-", "a", "dini, S. Basso, A. Brez, O. Citterio, S. di Cosimo, V. Cotroneo, S. Fabiani,", "M. Feroci, A. Ferri, L. Latronico, F. Lazzarotto, M. Minuti, E. Morelli,", "F. Muleri, L. Nicolini, G. Pareschi, G. di Persio, M. Pinchera, M. Razzano,", "L. Reboa, A. Rubini, A. M. Salonico, C. Sgro\u2019, P. Soffitta, G. Spandre,", "D. Spiga, and A. Trois, POLARIX: a pathfinder mission of X-ray polarime-", "try, Experimental Astronomy 28, 137\u2013183 (2010).", "[65] G. Tagliaferri, A. Argan, R. Bellazzini, J. Bookbinder, O. Catalano,", "E. Cavazzuti, E. Costa, G. Cusumano, F. Fiore, C. Fiorini, P. Giommi,", "G. Malaguti, G. Matt, S. Mereghetti, G. Micela, S. Murray, B. Negri,", "G. Pareschi, G. Perola, S. Romaine, and G. Villa, NHXM: a New Hard", "X-ray imaging and polarimetric Mission, in \u201cSociety of Photo-Optical In-", "strumentation Engineers (SPIE) Conference Series,\u201d , vol. 7732 of Soci-", "ety of Photo-Optical Instrumentation Engineers (SPIE) Conference Series", "(2010), vol. 7732 of Society of Photo-Optical Instrumentation Engineers", "(SPIE) Conference Series, p. 17.", "[66] K. Jahoda, The Gravity and Extreme Magnetism Small Explorer, in \u201cSoci-", "ety of Photo-Optical Instrumentation Engineers (SPIE) Conference Series,\u201d", ", vol. 7732 of Society of Photo-Optical Instrumentation Engineers (SPIE)", "Conference Series (2010), vol. 7732 of Society of Photo-Optical Instrumen-", "tation Engineers (SPIE) Conference Series.", "[67] R. Bellazzini and et al., A polarimeter for IXO, in \u201cX-ray Polarimetry: A", "New Window in Astrophysics by Ronaldo Bellazzini, Enrico Costa, Giorgio", "Matt and Gianpiero Tagliaferri. Cambridge University Press, 2010. ISBN:", "9780521191845, p. 269,\u201d , R. Bellazzini, E. Costa, G. Matt, and G. Taglia-", "ferri, eds. (2010), p. 269.", "[68] P. Soffitta, X. Barcons, R. Bellazzini, J. Braga, E. Costa, G. W. Fraser,", "S. Gburek, J. Huovelin, G. Matt, M. Pearce, J. Poutanen, V. Reglero,", "A. Santangelo, R. A. Sunyaev, G. Tagliaferri, M. Weisskopf, R. Aloisio,", "E. Amato, P. Attin \u0301, M. Axelsson, L. Baldini, S. Basso, S. Bianchi, P. Blasi,", "J. Bregeon, A. Brez, N. Bucciantini, L. Burderi, V. Burwitz, P. Casella,", "E. Churazov, M. Civitani, S. Covino, R. M. Curado da Silva, G. Cusumano,", "M. Dadina, F. D\u2019Amico, A. De Rosa, S. Di Cosimo, G. Di Persio, T. Di", "Salvo, M. Dovciak, R. Elsner, C. J. Eyles, A. C. Fabian, S. Fabiani, H. Feng,", "S. Giarrusso, R. W. Goosmann, P. Grandi, N. Grosso, G. Israel, M. Jackson,", "P. Kaaret, V. Karas, M. Kuss, D. Lai, G. L. Rosa, J. Larsson, S. Larsson,", "L. Latronico, A. Maggio, J. Maia, F. Marin, M. M. Massai, T. Mineo,", "M. Minuti, E. Moretti, F. Muleri, S. L. O\u2019Dell, G. Pareschi, G. Peres,", "M. Pesce, P.-O. Petrucci, M. Pinchera, D. Porquet, B. Ramsey, N. Rea,", "F. Reale, J. M. Rodrigo, A. R \u0301za \u0301ska, A. Rubini, P. Rudawy, F. Ryde,", "M. Salvati, V. A. de Santiago, S. Sazonov, C. Sgr \u0301, E. Silver, G. Spandre,", "D. Spiga, L. Stella, T. Tamagawa, F. Tamborra, F. Tavecchio, T. Teixeira", "Dias, M. van Adelsberg, K. Wu, and S. Zane, XIPE: the X-ray imaging", "polarimetry explorer, Experimental Astronomy 36, 523\u2013567 (2013).", "[69] D. Yonetoku, T. Murakami, H. Masui, H. Kodaira, Y. Aoyama, S. Gunji,", "F. Tokanai, and T. Mihara, Development of polarimeter for gamma-ray", "bursts onboard the solar-powered sail mission, in \u201cSociety of Photo-Optical", "Instrumentation Engineers (SPIE) Conference Series,\u201d , vol. 6266 of Soci-", "ety of Photo-Optical Instrumentation Engineers (SPIE) Conference Series", "(2006), vol. 6266 of Society of Photo-Optical Instrumentation Engineers", "(SPIE) Conference Series.", "[70] Y. Kishimoto, S. Gunji, Y. Ishigaki, M. Kanno, H. Murayama, C. Ito,", "F. Tokanai, K. Suzuki, H. Sakurai, T. Mihara, M. Kohama, M. Suzuki,", "A. Hayato, K. Hayashida, N. Anabuki, M. Morimoto, H. Tsunemi, Y. Saito,", "T. Yamagami, and S. Kishimoto, Basic Performance of PHENEX: A Po-", "larimeter for High ENErgy X rays, IEEE Transactions on Nuclear Science", "54, 561\u2013566 (2007).", "[71] T. Kamae, V. Andersson, M. Arimoto, M. Axelsson, C. Marini Bettolo, C.-", "I. Bj \u0308rnsson, G. Bogaert, P. Carlson, W. Craig, T. Ekeberg, O. Engdeg \u030a", "o", "ard,", "Y. Fukazawa, S. Gunji, L. Hjalmarsdotter, B. Iwan, Y. Kanai, J. Kataoka,", "N. Kawai, J. Kazejev, M. Kiss, W. Klamra, S. Larsson, G. Madejski,", "T. Mizuno, J. Ng, M. Pearce, F. Ryde, M. Suhonen, H. Tajima, H. Taka-", "hashi, T. Takahashi, T. Tanaka, T. Thurston, M. Ueno, G. Varner, K. Ya-", "mamoto, Y. Yamashita, T. Ylinen, and H. Yoshida, PoGOLite A high sen-", "sitivity balloon-borne soft gamma-ray polarimeter, Astroparticle Physics 30,", "72\u201384 (2008).", "[72] P. F. Bloser, J. S. Legere, M. L. McConnell, J. R. Macri, C. M. Bancroft,", "T. P. Connor, and J. M. Ryan, Calibration of the Gamma-RAy Polarimeter", "Experiment (GRAPE) at a polarized hard X-ray beam, Nuclear Instruments", "and Methods in Physics Research A 600, 424\u2013433 (2009).", "[73] S. Orsi and Polar Collaboration, POLAR: A Space-borne X-Ray Polarime-", "ter for Transient Sources, Astrophysics and Space Sciences Transactions 7,", "43\u201347 (2011).", "[74] F. A. Harrison, F. E. Christensen, W. Craig, C. Hailey, W. Baumgartner,", "C. M. H. Chen, J. Chonko, W. R. Cook, J. Koglin, K.-K. Madsen, M. Pi-", "vavoroff, S. Boggs, and D. Smith, Development of the HEFT and NuSTAR", "focusing telescopes, Experimental Astronomy 20, 131\u2013137 (2005).", "[75] H. Kunieda, H. Awaki, A. Furuzawa, Y. Haba, R. Iizuka, K. Ishibashi,", "M. Ishida, M. Itoh, T. Kosaka, Y. Maeda, H. Matsumoto, T. Miyazawa,", "H. Mori, Y. Namba, Y. Ogasaka, K. Ogi, T. Okajima, Y. Suzuki,", "K. Tamura, Y. Tawara, K. Uesugi, K. Yamashita, and S. Yamauchi, Hard", "x-ray telescope to be onboard ASTRO-H, in \u201cSociety of Photo-Optical In-", "strumentation Engineers (SPIE) Conference Series,\u201d , vol. 7732 of Soci-", "ety of Photo-Optical Instrumentation Engineers (SPIE) Conference Series", "(2010), vol. 7732 of Society of Photo-Optical Instrumentation Engineers", "(SPIE) Conference Series.", "[76] M. Beilicke, F. Kislat, A. Zajczyk, Q. Guo, R. Endsley, M. Stork, R. Cowsik,", "P. Dowkontt, S. Barthelmy, T. Hams, T. Okajima, M. Sasaki, B. Zeiger,", "G. de Geronimo, M. G. Baring, and H. Krawczynski, Design and Perfor-", "mance of the X-ray Polarimeter X-Calibur, Journal of Astronomical Instru-", "mentation 3, 1440008 (2014).", "[77] K. Hayashida, D. Yonetoku, S. Gunji, T. Tamagawa, T. Mihara, T. Mizuno,", "H. Takahashi, T. Dotani, H. Kubo, Y. Yatsu, F.