In this paper we present the science potential of the enhanced X-ray Timing and PolarimetryeXTP mission for studies of strongly magnetized objects. We will focus on the physics and astrophysics of strongly magnetized objects, namely magnetars, accreting X-ray pulsars, and rotation powered pulsars. We also discuss the science potential of eXTPfor QED studies. Developed by an international Consortium led by the Institute of High Energy Physics of theChinese Academy of Sciences, the eXTPmission is expected to be launched in the mid 2020s.
The Chinese team acknowledges the support of the Chinese Academy of Sciences through the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No. XDA15020100). This work was supported by the Bundesministerium fuer Wirtschaft und Technologie through the Deutsches Zentrum fuer Luft- und Raumfahrte.V. (DLR) (Grant No. FKZ 50 OO 1701). Financial contribution from the agreement between the Italian Space Agency and the Istituto Nazionale di Astrofisica ASI-INAF n.2017-14-H.O is acknowledged.
This paper is an initiative of the eXTP’s Science Working Group on Strong Magnetism, whose members are representatives of the astronomical community at large with a scientific interest in pursuing the successful implementation of eXTP. The paper was primaly written by by Andrea Santangelo, Silvia Zane, Hua Feng and RenXin Xu. Major contributions by Andrea Santangelo, Victor Doroshenko, Mauro Orlandini (sects. 3.1-3.4); RenXin Xu, ZhaoSheng Li, Lin Lin (sects. 2.2 and 2.3); Hao Tong (sect. 2.5); Silvia Zane (sects. 2.1-3.5); Nanda Rea, Paolo Esposito and Francesco Coti Zelati (sect. 2.2.2); Gianluca Israel and Daniela Huppenkoten (sect. 2.3.4); Roberto Turolla and Roberto Taverna (sects. 2.2.2 and 4.2); Denis Gonz′alez-Caniulef (sect. 4.2); Roberto Mignani (sect. 3.5); Jeremy Heyl and Ilaria Caiazzo (sect. 4). Contributions were edited by Andrea Santangelo, Silvia Zane and Victor Doroshenko. Other co-authors provided valuable inputs to refine the paper.
[1] S-N. Zhang et al. Science China Physics, Mechanics& Astronomy, this issue (eXTP White Paper on the Instrumentation and Mission). Google Scholar
[2] Kaspi V. M.. Proc. Natl. Acad. Sci. USA, 2010, 107: 7147-7152 CrossRef PubMed ADS arXiv Google Scholar
[3] Duncan R. C., Thompson C.. Astrophys. J., 1992, 392: L9-L13 CrossRef ADS Google Scholar
[4] Thompson C., Duncan R. C.. Astrophys. J., 1993, 408: 194-217 CrossRef ADS Google Scholar
[5] Mereghetti S.. Astron Astrophys Rev, 2008, 15: 225-287 CrossRef ADS arXiv Google Scholar
[6] Tong H.. Sci. China-Phys. Mech. Astron., 2016, 59: 619501 CrossRef ADS arXiv Google Scholar
[7] Sturrock P. A., Harding A. K., Daugherty J. K.. Astrophys. J., 1989, 346: 950-959 CrossRef ADS Google Scholar
[8] Turolla R., Zane S., Watts A. L.. Rep. Prog. Phys., 2015, 78: 116901 CrossRef PubMed ADS arXiv Google Scholar
[9] Taverna R., Turolla R.. Mon. Not. R. Astron. Soc., 2017, 469: 3610-3628 CrossRef ADS arXiv Google Scholar
[10] Ibrahim A. I., Swank J. H., Parke W.. Astrophys. J., 2003, 584: L17-L21 CrossRef ADS Google Scholar
[11] Israel G. L., Romano P., Mangano V., Dall'Osso S., Chincarini G., Stella L., Campana S., Belloni T., Tagliaferri G., Blustin A. J., Sakamoto T., Hurley K., Zane S., Moretti A., Palmer D., Guidorzi C., Burrows D. N., Gehrels N., Krimm H. A.. Astrophys. J., 2008, 685: 1114-1128 CrossRef ADS arXiv Google Scholar
[12]
N. Rea, and P. Esposito, in
[13] Harrison F. A., Craig W. W., Christensen F. E., Hailey C. J., Zhang W. W., Boggs S. E., Stern D., Cook W. R., Forster K., Giommi P., Grefenstette B. W., Kim Y., Kitaguchi T., Koglin J. E., Madsen K. K., Mao P. H., Miyasaka H., Mori K., Perri M., Pivovaroff M. J., Puccetti S., Rana V. R., Westergaard N. J., Willis J., Zoglauer A., An H., Bachetti M., Barrière N. M., Bellm E. C., Bhalerao V., Brejnholt N. F., Fuerst F., Liebe C. C., Markwardt C. B., Nynka M., Vogel J. K., Walton D. J., Wik D. R., Alexander D. M., Cominsky L. R., Hornschemeier A. E., Hornstrup A., Kaspi V. M., Madejski G. M., Matt G., Molendi S., Smith D. M., Tomsick J. A., Ajello M., Ballantyne D. R., Balokovi? M., Barret D., Bauer F. E., Blandford R. D., Brandt W. N., Brenneman L. W., Chiang J., Chakrabarty D., Chenevez J., Comastri A., Dufour F., Elvis M., Fabian A. C., Farrah D., Fryer C. L., Gotthelf E. V., Grindlay J. E., Helfand D. J., Krivonos R., Meier D. L., Miller J. M., Natalucci L., Ogle P., Ofek E. O., Ptak A., Reynolds S. P., Rigby J. R., Tagliaferri G., Thorsett S. E., Treister E., Urry C. M.. Astrophys. J., 2013, 770: 103 CrossRef ADS arXiv Google Scholar
[14] Taverna R., Muleri F., Turolla R., Soffitta P., Fabiani S., Nobili L.. Mon. Not. R. Astron. Soc., 2014, 438: 1686-1697 CrossRef ADS arXiv Google Scholar
[15] González-Caniulef D., Zane S., Taverna R., Turolla R., Song X., Wu K.. J. Phys.-Conf. Ser., 2017, 932: 012024 CrossRef ADS Google Scholar
[16] Gonzalez, C. D. et al, 2017b, in prep. Google Scholar
[17] Archibald R. F., Kaspi V. M., Ng C. Y., Gourgouliatos K. N., Tsang D., Scholz P., Beardmore A. P., Gehrels N., Kennea J. A.. Nature, 2013, 497: 591-593 CrossRef PubMed ADS arXiv Google Scholar
[18] Espinoza C. M., Antonopoulou D., Stappers B. W., Watts A., Lyne A. G.. Mon. Not. R. Astron. Soc., 2014, 440: 2755-2762 CrossRef ADS arXiv Google Scholar
[19] A. Watts, C. M. Espinoza, R. Xu, et al. Proceedings of Advancing Astrophysics with the Square Kilometre Array (AASKA14). 9-13 June (2014). Giardini Naxos, Italy, id.43, 2015. Google Scholar
[20] Huang Y. F., Geng J. J.. Astrophys. J., 2014, 782: L20 CrossRef ADS arXiv Google Scholar
[21] Tong H.. Astrophys. J., 2014, 784: 86 CrossRef ADS arXiv Google Scholar
[22] Xu R. X., Tao D. J., Yang Y.. Mon. Not. R. Astron. Soc.-Lett., 2006, 373: L85-L89 CrossRef ADS Google Scholar
[23] Zhou E. P., Lu J. G., Tong H., Xu R. X.. Mon. Not. R. Astron. Soc., 2014, 443: 2705-2710 CrossRef ADS arXiv Google Scholar
[24] Thompson C., Lyutikov M., Kulkarni S. R.. Astrophys. J., 2002, 574: 332-355 CrossRef ADS Google Scholar
[25] Makishima K., Enoto T., Hiraga J. S., Nakano T., Nakazawa K., Sakurai S., Sasano M., Murakami H.. Phys. Rev. Lett., 2014, 112: 171102 CrossRef PubMed ADS arXiv Google Scholar
[26] Sedrakian A.. Astron. Astrophys., 2016, 587: L2 CrossRef ADS arXiv Google Scholar
[27] A. Sedkranian, X. G. Huang, M. Sinha, et al, Proceedings of “Compact Stars in the QCD phase diagram V, 23-27 May 2016 GSSI and LNGS, LAquila, Italy, Journal of Physics: Conf. Series, 861, 012025 (2017). Google Scholar
[28] Xu R.. Adv. Space Res., 2007, 40: 1453-1459 CrossRef ADS Google Scholar
[29] Lyne A. G., Jordan C. A., Graham-Smith F., Espinoza C. M., Stappers B. W., Weltevrede P.. Mon. Not. R. Astron. Soc., 2015, 446: 857-864 CrossRef ADS arXiv Google Scholar
[30] Hobbs G., Lyne A. G., Kramer M.. Mon. Not. R. Astron. Soc., 2010, 402: 1027-1048 CrossRef ADS arXiv Google Scholar
[31] Ou Z. W., Tong H., Kou F. F., Ding G. Q.. Mon. Not. R. Astron. Soc., 2016, 457: 3922-3933 CrossRef ADS arXiv Google Scholar
[32] H. Tong, R. Xu, L. Song, G. Qiao, Astrophys. J. 768, 144 (2016). Google Scholar
[33] Pintore F., Bernardini F., Mereghetti S., Esposito P., Turolla R., Rea N., Coti Zelati F., Israel G. L., Tiengo A., Zane S.. Mon. Not. R. Astron. Soc., 2016, 458: 2088-2093 CrossRef ADS arXiv Google Scholar
[34] Israel G. L., Belloni T., Stella L., Rephaeli Y., Gruber D. E., Casella P., Dall'Osso S., Rea N., Persic M., Rothschild R. E.. Astrophys. J., 2005, 628: L53-L56 CrossRef ADS Google Scholar
[35] Watts A. L., Strohmayer T. E.. Astrophys. J., 2006, 637: L117-L120 CrossRef ADS Google Scholar
[36] Strohmayer T. E., Watts A. L.. Astrophys. J., 2006, 653: 593-601 CrossRef ADS Google Scholar
[37] Strohmayer T. E., Watts A. L.. Astrophys. J., 2005, 632: L111-L114 CrossRef ADS Google Scholar
[38] Huppenkothen D., Watts A. L., Uttley P., van der Horst A. J., van der Klis M., Kouveliotou C., G??ü? E., Granot J., Vaughan S., Finger M. H.. Astrophys. J., 2013, 768: 87 CrossRef ADS arXiv Google Scholar
[39] Huppenkothen D., D'Angelo C., Watts A. L., Heil L., van der Klis M., van der Horst A. J., Kouveliotou C., Baring M. G., G??ü? E., Granot J., Kaneko Y., Lin L., von Kienlin A., Younes G.. Astrophys. J., 2014, 787: 128 CrossRef ADS arXiv Google Scholar
[40] Huppenkothen D., Heil L. M., Watts A. L., G??ü? E.. Astrophys. J., 2014, 795: 114 CrossRef ADS arXiv Google Scholar
[41] Samuelsson L., Andersson N.. Mon. Not. R. Astron. Soc., 2007, 374: 256-268 CrossRef ADS Google Scholar
[42] Watts A. L., Reddy S.. Mon. Not. R. Astron. Soc.-Lett., 2007, 379: L63-L66 CrossRef ADS Google Scholar
[43] Levin Y.. Mon. Not. R. Astron. Soc., 2007, 377: 159-167 CrossRef ADS Google Scholar
[44] Hoven M., Levin Y.. Mon. Not. R. Astron. Soc., 2011, 410: 1036-1051 CrossRef ADS arXiv Google Scholar
[45] van Hoven M., Levin Y.. Mon. Not. R. Astron. Soc., 2012, 420: 3035-3046 CrossRef ADS arXiv Google Scholar
[46] Colaiuda A., Kokkotas K. D.. Mon. Not. R. Astron. Soc., 2011, 414: 3014-3022 CrossRef ADS arXiv Google Scholar
[47] Gabler M., Cerdá-Durán P., Stergioulas N., Font J. A., Müller E.. Mon. Not. R. Astron. Soc., 2012, 421: 2054-2078 CrossRef ADS arXiv Google Scholar
[48] Gabler M., Cerda-Duran P., Font J. A., Muller E., Stergioulas N.. Mon. Not. R. Astron. Soc., 2013, 430: 1811-1831 CrossRef ADS arXiv Google Scholar
[49] Andersson N., Glampedakis K., Haskell B.. Phys. Rev. D, 2009, 79: 103009 CrossRef ADS arXiv Google Scholar
[50] Steiner A. W., Watts A. L.. Phys. Rev. Lett., 2009, 103: 181101 CrossRef PubMed ADS arXiv Google Scholar
[51] Passamonti A., Lander S. K.. Mon. Not. R. Astron. Soc., 2013, 429: 767-774 CrossRef ADS arXiv Google Scholar
[52] Passamonti A., Lander S. K.. Mon. Not. R. Astron. Soc., 2014, 438: 156-168 CrossRef ADS arXiv Google Scholar
[53] Tiengo A., Esposito P., Mereghetti S., Turolla R., Nobili L., Gastaldello F., G?tz D., Israel G. L., Rea N., Stella L., Zane S., Bignami G. F.. Nature, 2013, 500: 312-314 CrossRef PubMed ADS arXiv Google Scholar
[54] Esposito P., Israel G. L., Turolla R., Tiengo A., G?tz D., De Luca A., Mignani R. P., Zane S., Rea N., Testa V., Caraveo P. A., Chaty S., Mattana F., Mereghetti S., Pellizzoni A., Romano P.. Mon. Not. R. Astron. Soc., 2010, 53: 1787-1795 CrossRef ADS arXiv Google Scholar
[55] Rodríguez Castillo G. A., Israel G. L., Tiengo A., Salvetti D., Turolla R., Zane S., Rea N., Esposito P., Mereghetti S., Perna R., Stella L., Pons J. A., Campana S., G?tz D., Motta S.. Mon. Not. R. Astron. Soc., 2016, 456: 4145-4155 CrossRef ADS arXiv Google Scholar
[56] Borghese A., Rea N., Zelati F. C., Tiengo A., Turolla R.. Astrophys. J., 2015, 807: L20 CrossRef ADS arXiv Google Scholar
[57] Borghese A., Rea N., Coti Zelati F., Tiengo A., Turolla R., Zane S.. Mon. Not. R. Astron. Soc., 2017, 468: 2975-2983 CrossRef ADS arXiv Google Scholar
[58] Tong H.. Res. Astron. Astrophys., 2015, 15: 517-524 CrossRef ADS arXiv Google Scholar
[59] Tsygankov S. S., Mushtukov A. A., Suleimanov V. F., Poutanen J.. Mon. Not. R. Astron. Soc., 2016, 457: 1101-1106 CrossRef ADS arXiv Google Scholar
[60] Torres D. F., Rea N., Esposito P., Li J., Chen Y., Zhang S.. Astrophys. J., 2012, 744: 106 CrossRef ADS arXiv Google Scholar
[61] Israel G. L., Papitto A., Esposito P., Stella L., Zampieri L., Belfiore A., Rodríguez Castillo G. A., De Luca A., Tiengo A., Haberl F., Greiner J., Salvaterra R., Sandrelli S., Lisini G.. Mon. Not. R. Astron. Soc-Lett., 2017, 466: L48-L52 CrossRef ADS arXiv Google Scholar
[62] Israel G. L., Belfiore A., Stella L., Esposito P., Casella P., De Luca A., Marelli M., Papitto A., Perri M., Puccetti S., Castillo G. A. R., Salvetti D., Tiengo A., Zampieri L., D'Agostino D., Greiner J., Haberl F., Novara G., Salvaterra R., Turolla R., Watson M., Wilms J., Wolter A.. Science, 2017, 355: 817-819 CrossRef PubMed ADS arXiv Google Scholar
[63] Bachetti M., Harrison F. A., Walton D. J., Grefenstette B. W., Chakrabarty D., Fürst F., Barret D., Beloborodov A., Boggs S. E., Christensen F. E., Craig W. W., Fabian A. C., Hailey C. J., Hornschemeier A., Kaspi V., Kulkarni S. R., Maccarone T., Miller J. M., Rana V., Stern D., Tendulkar S. P., Tomsick J., Webb N. A., Zhang W. W.. Nature, 2014, 514: 202-204 CrossRef PubMed ADS arXiv Google Scholar
[64] DallOsso S., Perna R., Stella L.. Mon. Not. R. Astron. Soc., 2015, 449: 2144-2150 CrossRef ADS arXiv Google Scholar
[65] Ghosh P., Lamb F. K.. Astrophys. J., 1979, 232: 259-276 CrossRef ADS Google Scholar
[66] Doroshenko V., Santangelo A., Suleimanov V.. Astron. Astrophys., 2011, 529: A52 CrossRef ADS arXiv Google Scholar
[67] Bozzo E., Falanga M., Stella L.. Astrophys. J., 2008, 683: 1031-1044 CrossRef ADS arXiv Google Scholar
[68] Doroshenko V., Santangelo A., Ducci L., Klochkov D.. Astron. Astrophys., 2012, 548: A19 CrossRef ADS arXiv Google Scholar
[69] Revnivtsev M., Mereghetti S.. Space Sci Rev, 2015, 191: 293-314 CrossRef ADS arXiv Google Scholar
[70] A. Santangelo, A. Segreto, S. Giarrusso, D. Dal Fiume, and M. Orlandini, Astron. Astrophys. 523, L85 (1975). Google Scholar
[71] Basko M. M., Sunyaev R. A.. Mon. Not. R. Astron. Soc., 1976, 175: 395-417 CrossRef ADS Google Scholar
[72] Becker P. A., Klochkov D., Sch?nherr G., Nishimura O., Ferrigno C., Caballero I., Kretschmar P., Wolff M. T., Wilms J., Staubert R.. Astron. Astrophys., 2012, 544: A123 CrossRef ADS arXiv Google Scholar
[73] Doroshenko V., Tsygankov S. S., Mushtukov A. A., Lutovinov A. A., Santangelo A., Suleimanov V. F., Poutanen J.. Mon. Not. R. Astron. Soc., 2017, 466: 2143-2150 CrossRef ADS arXiv Google Scholar
[74] Mushtukov A. A., Suleimanov V. F., Tsygankov S. S., Poutanen J.. Mon. Not. R. Astron. Soc., 2015, 447: 1847-1856 CrossRef ADS arXiv Google Scholar
[75] Mushtukov A. A., Tsygankov S. S., Serber A. V., Suleimanov V. F., Poutanen J.. Mon. Not. R. Astron. Soc., 2015, 454: 2714-2721 CrossRef ADS arXiv Google Scholar
[76] Burnard D. J., Arons J., Klein R. I.. Astrophys. J., 1991, 367: 575-592 CrossRef ADS Google Scholar
[77] Becker P. A., Wolff M. T.. Astrophys. J., 2007, 654: 435-457 CrossRef ADS Google Scholar
[78] Ferrigno C., Becker P. A., Segreto A., Mineo T., Santangelo A.. Astron. Astrophys., 2009, 498: 825-836 CrossRef ADS arXiv Google Scholar
[79] Poutanen J., Mushtukov A. A., Suleimanov V. F., Tsygankov S. S., Nagirner D. I., Doroshenko V., Lutovinov A. A.. Astrophys. J., 2013, 777: 115 CrossRef ADS arXiv Google Scholar
[80] Meszaros P., Novick R., Szentgyorgyi A., Chanan G. A., Weisskopf M. C.. Astrophys. J., 1988, 324: 1056-1067 CrossRef ADS Google Scholar
[81] V. Canuto, and J. Ventura, FCPh, 2, 203 (1977). Google Scholar
[82] EPJ Web Conf., 2014, 64: 02003 CrossRef ADS
[83] Staubert R., Shakura N. I., Postnov K., Wilms J., Rothschild R. E., Coburn W., Rodina L., Klochkov D.. Astron. Astrophys., 2007, 465: L25-L28 CrossRef ADS Google Scholar
[84] Sch?nherr G., Wilms J., Kretschmar P., Kreykenbohm I., Santangelo A., Rothschild R. E., Coburn W., Staubert R.. Astron. Astrophys., 2007, 472: 353-365 CrossRef ADS arXiv Google Scholar
[85] Nishimura O.. Astrophys. J., 2011, 730: 106 CrossRef ADS Google Scholar
[86] Kraus U., Zahn C., Weth C., Ruder H.. Astrophys. J., 2003, 590: 424-431 CrossRef ADS Google Scholar
[87] Klochkov D., Ferrigno C., Santangelo A., Staubert R., Kretschmar P., Caballero I., Postnov K., Wilson-Hodge C. A.. Astron. Astrophys., 2011, 536: L8 CrossRef ADS arXiv Google Scholar
[88] Klochkov D., Staubert R., Santangelo A., Rothschild R. E., Ferrigno C.. Astron. Astrophys., 2011, 532: A126 CrossRef ADS arXiv Google Scholar
[89] M. Orlandini, D. dal Fiume, F. Frontera, G. Cusumano, and S. del Sordo, Astron. Astrophys. 332, 121 (1998). Google Scholar
[90] Tsygankov S. S., Lutovinov A. A., Serber A. V.. Mon. Not. R. Astron. Soc., 2010, 401: 1628-1635 CrossRef ADS arXiv Google Scholar
[91] Arons J., Lea S. M.. Astrophys. J., 1976, 210: 792-804 CrossRef ADS Google Scholar
[92] Shakura N., Postnov K., Kochetkova A., Hjalmarsdotter L.. Mon. Not. R. Astron. Soc., 2012, 420: 216-236 CrossRef ADS arXiv Google Scholar
[93] Orlandini M., Morfill G. E.. Astrophys. J., 1992, 386: 703-709 CrossRef ADS Google Scholar
[94] Orlandini M., Boldt E.. Astrophys. J., 1993, 419: 776 CrossRef ADS Google Scholar
[95] Herold H.. Phys. Rev. D, 1979, 19: 2868-2875 CrossRef ADS Google Scholar
[96] R. I. Klein, J. Arons, G. Jernigan, and J. J.-L. Hsu, Astrophys. J. 457, L85 (1996). Google Scholar
[97] Turolla R., Zane S., Watts A. L.. Rep. Prog. Phys., 2015, 78: 116901 CrossRef PubMed ADS arXiv Google Scholar
[98] Pierbattista M., Harding A. K., Gonthier P. L., Grenier I. A.. Astron. Astrophys., 2016, 588: A137 CrossRef ADS arXiv Google Scholar
[99] Caraveo P. A.. Annu. Rev. Astron. Astrophys., 2014, 52: 211-250 CrossRef ADS arXiv Google Scholar
[100] Degrange B., Fontaine G.. Comptes Rendus Physique, 2015, 16: 587-599 CrossRef ADS arXiv Google Scholar
[101] Marelli M., Mignani R. P., Luca A. D., Parkinson P. M. S., Salvetti D., Hartog P. R. D., Wolff M. T.. Astrophys. J., 2015, 802: 78 CrossRef ADS arXiv Google Scholar
[102] Shearer A.. Science, 2003, 301: 493-495 CrossRef PubMed ADS Google Scholar
[103] Collins, S. et al. New Horizons in Time-Domain Astronomy, Proceedings of the International Astronomical, Union, IAU Symposium 285, 296 (2012). Google Scholar
[104] Strader M. J., Johnson M. D., Mazin B. A., Spiro Jaeger G. V., Gwinn C. R., Meeker S. R., Szypryt P., van Eyken J. C., Marsden D., OBrien K., Walter A. B., Ulbricht G., Stoughton C., Bumble B.. Astrophys. J., 2013, 779: L12 CrossRef ADS arXiv Google Scholar
[105] Bilous A. V., McLaughlin M. A., Kondratiev V. I., Ransom S. M.. Astrophys. J., 2012, 749: 24 CrossRef ADS arXiv Google Scholar
[106] Hitomi Collaboration, PASJ, accepted,. arXiv Google Scholar
[107] Lundgren S. C., Cordes J. M., Ulmer M., Matz S. M., Lomatch S., Foster R. S., Hankins T.. Astrophys. J., 1995, 453: 433 CrossRef ADS Google Scholar
[108] Bilous A. V., Kondratiev V. I., McLaughlin M. A., Ransom S. M., Lyutikov M., Mickaliger M., Langston G. I.. Astrophys. J., 2011, 728: 110 CrossRef ADS arXiv Google Scholar
[109] Aliu E., Archambault S., Arlen T., Aune T., Beilicke M., Benbow W., Bouvier A., Buckley J. H., Bugaev V., Byrum K., Cesarini A., Ciupik L., Collins-Hughes E., Connolly M. P., Cui W., Dickherber R., Duke C., Dumm J., Falcone A., Federici S., Feng Q., Finley J. P., Finnegan G., Fortson L., Furniss A., Galante N., Gall D., Gillanders G. H., Godambe S., Griffin S., Grube J., Gyuk G., Hanna D., Holder J., Huan H., Hughes G., Humensky T. B., Kaaret P., Karlsson N., Khassen Y., Kieda D., Krawczynski H., Krennrich F., Lang M. J., LeBohec S., Lee K., Lyutikov M., Madhavan A. S., Maier G., Majumdar P., McArthur S., McCann A., Moriarty P., Mukherjee R., Nelson T., de Bhróithe A. O. F., Ong R. A., Orr M., Otte A. N., Park N., Perkins J. S., Pohl M., Prokoph H., Quinn J., Ragan K., Reyes L. C., Reynolds P. T., Roache E., Saxon D. B., Schroedter M., Sembroski G. H., ?entürk G. D., Smith A. W., Staszak D., Telezhinsky I., Te?i? G., Theiling M., Thibadeau S., Tsurusaki K., Varlotta A., Vincent S., Vivier M., Wagner R. G., Wakely S. P., Weekes T. C., Weinstein A., Welsing R., Williams D. A., Zitzer B.. Astrophys. J., 2012, 760: 136 CrossRef ADS arXiv Google Scholar
[110]
R. Mikami, T. Terasawa, S. Kisaka, A. Katsuaki, S. J. Tanaka, M. Sekido, K. Takefuji, H. Takeuchi, H. Odaka, T. Sato, Y. T. Tanaka, and N. Kawai, in
[111] Mignani et al,. arXiv Google Scholar
[112] Heisenberg W., Euler H.. Z. Physik, 1936, 98: 714-732 CrossRef ADS Google Scholar
[113] V. S. Weisskopf, Uber die elektrodynamik des vakuums auf grund der quantentheorie des elektrons, Kongelige Danske Videnskaberns Selskab, Mathematisk-Fysiske Meddelelser, 14, 1 (1936). Google Scholar
[114] Schwinger J.. Phys. Rev., 1951, 82: 664-679 CrossRef ADS Google Scholar
[115] Heyl J. S., Hernquist L.. J. Phys. A-Math. Gen., 1997, 30: 6485-6492 CrossRef ADS Google Scholar
[116] Heyl J. S., Shaviv N. J.. Mon. Not. R. Astron. Soc., 2000, 311: 555-564 CrossRef ADS Google Scholar
[117] Kii, T, PASJ, 39, 781 (1987). Google Scholar
[118] I. Caiazzo and J. Heyl, PRD, 2017, submitted. Google Scholar
[119] J. S. Heyl, D. Lloyd, and N. J. Shaviv,. arXiv Google Scholar
[120] Mignani R. P., Testa V., González Caniulef D., Taverna R., Turolla R., Zane S., Wu K.. Mon. Not. R. Astron. Soc., 2017, 465: 492-500 CrossRef ADS arXiv Google Scholar
[121] González Caniulef D., Zane S., Taverna R., Turolla R., Wu K.. Mon. Not. R. Astron. Soc., 2016, 459: 3585-3595 CrossRef ADS arXiv Google Scholar
[122] Albano A., Turolla R., Israel G. L., Zane S., Nobili L., Stella L.. Astrophys. J., 2010, 722: 788-802 CrossRef ADS arXiv Google Scholar
[123] Bernardini F., Israel G. L., DallOsso S., Stella L., Rea N., Zane S., Turolla R., Perna R., Falanga M., Campana S., G?tz D., Mereghetti S., Tiengo A.. Astron. Astrophys., 2009, 498: 195-207 CrossRef ADS arXiv Google Scholar
[124] An H., Kaspi V. M., Archibald R., Cumming A.. Astrophys. J., 2013, 763: 82 CrossRef ADS arXiv Google Scholar
[125] Taverna R., Muleri F., Turolla R., Soffitta P., Fabiani S., Nobili L.. Mon. Not. R. Astron. Soc., 2014, 438: 1686-1697 CrossRef ADS arXiv Google Scholar
[126] Thompson C., Duncan R. C.. Mon. Not. R. Astron. Soc., 1995, 275: 255-300 CrossRef ADS Google Scholar
[127] Mereghetti S.. Astron Astrophys Rev, 2008, 15: 225-287 CrossRef ADS arXiv Google Scholar
[128] V. Canuto, and J. Ventura, FCPh, 2, 203 (1977). Google Scholar
[129] Tsygankov S. S., Lutovinov A. A., Serber A. V.. Mon. Not. R. Astron. Soc., 2010, 401: 1628-1635 CrossRef ADS arXiv Google Scholar
[130] Thompson C., Duncan R. C.. Mon. Not. R. Astron. Soc., 1995, 275: 255-300 CrossRef ADS Google Scholar
Figure 1
Period and period derivative diagram of neutron stars, including normal pulsars (black points), magnetars (blue squares, empty squares for radio loud magnetars), X-ray dim isolated neutron stars (green diamonds), central compact objects (light blue circles), rotating radio transients (red stars) and intermittent pulsars (magenta triangles)
Figure 2
Simulated WFM spectrum of a magnetar burst (black points) for a 0.05 s burst duration, assuming a flux of 10 Crab (left) and 150 Crab (right), and a double blackbody spectrum.
Figure 3
Simulated LAD spectrum of a magnetar burst (black points) for a 0.05 s burst duration, assuming a flux of 10 Crab, a double blackbody spectrum, and an absorption feature at 4.5 keV (200 eV EW). The red line in the top panel shows the best-fit model obtained assuming a double blackbody spectrum. The lower panel shows the residuals with respect to the best-fit model, when the CRSF is not included.
Figure 4
Simulated polarization fraction (a) and angle (b) as measured by the eXTPpolarimeter for an intermediate burst computed according to model a (orange crosses) and model b (red crosses) of ref.
Figure 5
eXTPsimulation of a small glitch with/without X-ray outburst. The input spectrum is a combination of a blackbody and a power law, absorbed at lower energies. The hydrogen column density, the blackbody temperature and its normalization are $0.95\times10^{22}{\rm~cm^{-2}}$, $0.395~{\rm~keV}$ and $0.1558$, respectively. Points indicate observations of 2 ks spaced by intervals of 2 weeks, hence the total exposure time is $3.34\times10^{4}\rm{s}$. In the bottom panel, the red data show the X-ray outburst during a small glitch, while the black data represent the persistent emission.
Figure 6
eXTPsimulation of free precession in SGR 1900+14. The input spectrum is a blackbody plus a power law, with low energy absorption. The hydrogen column density, the blackbody temperature and its normalization for SGR 1900+14 are $1.6\times10^{22}{\rm~cm^{-2}}$, 0.5 and 7.1 keV, respectively. The sinusoidal modulation of the free precession is assumed. Points indicate observations of 2 ks spaced by intervals of 2 weeks, hence the total exposure time is $1.15\times10^{5}\rm{s}$.
Figure 7
$\ddot{\nu}$ versus $\dot{\nu}$ for pulsars and magnetars. Black “+" stands for pulsars with postive $\ddot{\nu}$ and black “$\circ$" for negative $\ddot{\nu}$. Blue “+" and “$\circ$" are for magnetars. The lines are model calculations with different fluctuation amplitude. Updated from Figure
Figure 8
Black: simulated LAD eXTPdata of the lightcurve of the IF observed from SGR 1900$+$14 in 2006, with quasi-periodic oscillations at 30, 92, 150, 625, 976, and 1840 Hz, at a fractional rms amplitude of $50%$ (with respect to that observed from the GF of SGR 1806$-$20). Overplotted in color are ten realizations from the posterior distribution of a mixture model of Lorentzian components, clearly identifying all but the lowest-frequency QPO present in the data.
Figure 9
(a) An artist's impression of the magnetic field topology inferred for the magnetar SGR 0418+5729 thanks to the discovery of a prominent cyclotron line around 2 keV
Figure 10
(a) An example of the eXTPLAD capability to reconstruct the spectral shape of an accreting X-ray pulsar in very short integration times. Simulations were performed using the results of a BeppoSAX observation of Vela X-1
Figure 11
The pulse amplitude, the linear polarization fraction and the degree of polarization as a function of the pulse phase are shown, assuming the spectrum of Vela X-1. An exposure of 7 ks/phase has been chosen together with 10 phases. Total exposure is 70 ks. A combination of $i_1~=45^\circ$ and $i_2=45^\circ$ has also been chosen.
Figure 12
The unique capabilities of eXTPin detecting microsecond bursting activity from wind-accreting NSs. The ratio between the detection rate $R_B$ of true micro-bursts, and the rate $R_A$ of spurious bursts, is plotted as a function of the source count rate $R_s$, for the case of a moderate granularity (10%) in the accretion stream. The two vertical lines mark the count rates for two Vela X-1 luminosity states (low: 15 mCrab, soft spectrum; high: 45 mCrab, hard spectrum). $\lambda$ is the rate of formation of the blobs at the magnetospheric limit
Figure 13
The expected fraction of linear polarization from the surface of strongly magnetized neutron stars with hydrogen atmospheres and effective temperatures of $10^{6.5}$ K (from ref.
Figure 14
(a) The total degree of polarization as a function of phase expected from AXP 4U 0142+614 with and without QED averaged over energy; (b) total polarization averaged over the rotation of Her X-1 (see text). The eXTPsimulation assumes a radius of 10 km and QED. The solid curves include QED birefringence and the dashed curves do not.
Figure 15
(a) Phase-averaged PF for the thermal radiation emitted from a TM at the peak of the outburst (without vacuum birefringence) computed for different values of the angles $\xi$ (between the magnetic axis and spin axis) and $\chi$ (between the line of sight and spin axis). The radiation is computed for a magnetized NS atmosphere, with $B\sim10^{14}$ G and assuming emission from one hot polar cap covering $15%$ of the NS surface. (b) Same as in the left panel but accounting for the QED effects.
Figure 16
Expected variation of the phase-averaged PA for TMs during a magnetospheric untwisting of 0.5 rad (as expected during the outburst decay, for details see ref.
Figure 17
Maximum phase-averaged PF for different sizes of the polar cap (semi-angle of the polar cap). The line with asterisk symbols (*) corresponds to the case in which vacuum birefringence is operating. The line with crosses symbols (+) shows the case in which vacuum birefringence is not present. The radiation at the star surface is computed for a magnetized, pure-H atmosphere with $B_p=10^{14}$ G and temperature $T=0.5$ keV.
Figure 18
Simulations with eXTPshowing the significance of a detection of a PF$\sim$70% (sufficient to prove QED effects) as a function of the exposure. (a) X-ray flux $\sim$$10^{-11}$ erg cm$^{-2}$ s$^{-1}$, as typical of the outburst onset; (b) flux $\sim$$5\times10^{-13}$ erg cm$^{-2}$ s$^{-1}$, as representative of the quiescent state after decay.
Figure 19
Light curve, degree and angle of polarization as computed according to the “twisted magnetosphere” model with $\Delta\phi_{N-S}= ~~~~0.5$ rad, $\beta=~0.34$, $\chi=~90^{\circ}$ and $\xi~=~60^{\circ}$ for a source with properties similar to those of the AXP 1RXS J170849.0-400910. Data points (filled circles with error bars) are generated assuming a 100 ks observation of the source and are drawn from the model shown by the blue dotted line; in both cases QED effects are fully taken into account (“ON” case). The red dotted line represents the same model but without vacuum birefringence (“OFF” case). The simultaneous fit (solid blue line) of the “ON” data with the “ON” model gives a reduced $\chi^2=1.14$ while that of “ON” data with the “OFF” model is ruled out with high confidence.
Figure 20
Observed polarization fraction against photon energy for an initial polarization fraction of one. (a) Zero angular momentum photons (black solid line), maximum prograde angular momentum photons (highly blue-shifted, blue solid line) and maximum retrograde angular momentum photons (highly red-shifted, red solid line), coming from the ISCO of a black hole with $a_\star=0.9$; (b) maximum retrograde angular momentum photons for $a_\star=0.5$ (pink line), 0.7 (light blue line) and 0.9 (dark crimson line).
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