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1. IXPE observations of the quintessential wind-accreting X-ray pulsar Vela X-1

Author

Forsblom, Sv, Poutanen, J, Tsygankov, Ss, Bachetti, M, Marco, Ad, Doroshenko, V, Heyl, J, Monaca, Fl, Malacaria, C, Marshall, Hl, Muleri, F, Mushtukov, Aa, Pilia, M, Rogantini, D, Suleimanov, Vf, Taverna, R, Xie, F, Agudo, I, Antonelli, La, Baldini, L, Baumgartner, Wh, Bellazzini, R, Bianchi, S, Bongiorno, Sd, Bonino, R, Brez, A, Bucciantini, N, Capitanio, F, Castellano, S, Cavazzuti, E, Chen, Ct, Ciprini, S, Costa, E, De Rosa, A, Del Monte, E, Di Gesu, L, Di Lalla, N, Donnarumma, I, Dovciak, M, Ehlert, Sr, Enoto, T, Evangelista, Y, Fabiani, S, Ferrazzoli, R, Garcia, Ja, Gunji, S, Hayashida, K, Iwakiri, W, Jorstad, Sg, Kaaret, P, Karas, V, Kitaguchi, T, Kolodziejczak, Jj, Krawczynski, H, Latronico, L, Liodakis, I, Maldera, S, Manfreda, A, Marin, F, Marinucci, A, Marscher, Ap, Matt, G, Mitsuishi, I, Mizuno, T, Negro, M, Cy, Ng, O'Dell, Sl, Omodei, N, Oppedisano, C, Papitto, A, Pavlov, Gg, Peirson, Al, Perri, M, Pesce-Rollins, M, Petrucci, Po, Possenti, A, Puccetti, S, Ramsey, Bd, Rankin, J, Ratheesh, A, Roberts, Oj, Romani, Rw, Sgro, C, Slane, P, Soffitta, P, Spandre, G, Sunyaev, Ra, Swartz, Da, Tamagawa, T, Tavecchio, F, Tawara, Y, Tennant, Af, Thomas, Ne, Tombesi, F, Trois, A, Turolla, R, Vink, J, Weisskopf, Mc, Kw, Wu, Zane, S, Ixpe, Collaboration, Ministerio de Ciencia e Innovación (España), Academy of Finland, German Research Foundation, Forsblom, Sofia V., Poutanen, Juri, Tsygankov, Sergey S., Bachetti, Matteo, Marco, Alessandro Di, Doroshenko, Victor, Heyl, Jeremy, Monaca, Fabio La, Malacaria, Christian, Marshall, Herman L., Muleri, Fabio, Mushtukov, Alexander A., Pilia, Maura, Rogantini, Daniele, Suleimanov, Valery F., Taverna, Roberto, Xie, Fei, Agudo, Iván, Antonelli, Lucio A., Baldini, Luca, Baumgartner, Wayne H., Bellazzini, Ronaldo, Bianchi, Stefano, Bongiorno, Stephen D., Bonino, Raffaella, Brez, Alessandro, Bucciantini, Niccolò, Capitanio, Fiamma, Castellano, Simone, Cavazzuti, Elisabetta, Chen, Chien-Ting, Ciprini, Stefano, Costa, Enrico, De Rosa, Alessandra, Del Monte, Ettore, Di Gesu, Laura, Di Lalla, Niccolò, Donnarumma, Immacolata, Dovčiak, Michal, Ehlert, Steven R., Enoto, Teruaki, Evangelista, Yuri, Fabiani, Sergio, Ferrazzoli, Riccardo, Garcia, Javier A., Gunji, Shuichi, Hayashida, Kiyoshi, Iwakiri, Wataru, Jorstad, Svetlana G., Kaaret, Philip, Karas, Vladimir, Kitaguchi, Takao, Kolodziejczak, Jeffery J., Krawczynski, Henric, Latronico, Luca, Liodakis, Ioanni, Maldera, Simone, Manfreda, Alberto, Marin, Frédéric, Marinucci, Andrea, Marscher, Alan P., Matt, Giorgio, Mitsuishi, Ikuyuki, Mizuno, Tsunefumi, Negro, Michela, Ng, Chi-Yung, O’Dell, Stephen L., Omodei, Nicola, Oppedisano, Chiara, Papitto, Alessandro, Pavlov, George G., Peirson, Abel L., Perri, Matteo, Pesce-Rollins, Melissa, Petrucci, Pierre-Olivier, Possenti, Andrea, Puccetti, Simonetta, Ramsey, Brian D., Rankin, John, Ratheesh, Ajay, Roberts, Oliver J., Romani, Roger W., Sgrò, Carmelo, Slane, Patrick, Soffitta, Paolo, Spandre, Gloria, Sunyaev, Rashid A., Swartz, Douglas A., Tamagawa, Toru, Tavecchio, Fabrizio, Tawara, Yuzuru, Tennant, Allyn F., Thomas, Nicholas E., Tombesi, Francesco, Trois, Alessio, Turolla, Roberto, Vink, Jacco, Weisskopf, Martin C., Wu, Kinwah, and Zane, Silvia

Subjects
High Energy Astrophysical Phenomena (astro-ph.HE), Space and Planetary Science, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics - High Energy Astrophysical Phenomena
Abstract

Full list of authors: Forsblom, Sofia; Poutanen, Juri S.; Tsygankov, Sergey; Bachetti, Matteo; Marco, Alessandro Di; Doroshenko, Victor; Heyl, Jeremy; Monaca, Fabio La; Malacaria, Christian L.; Marshall, Herman; Muleri, Fabio A.; Mushtukov, Alexander; Pilia, Maura; Rogantini, Daniele F.; Suleimanov, Valery; Taverna, Roberto; Xie, Fei; Agudo, Ivan A.; Antonelli, Lucio; Baldini, Luca H.; Baumgartner, Wayne; Bellazzini, Ronaldo; Bianchi, Stefano D.; Bongiorno, Stephen; Bonino, Raffaella; Brez, Alessandro; Bucciantini, Niccolo; Capitanio, Fiamma; Castellano, Simone; Cavazzuti, Elisabetta; Chen, Chien-Ting; Ciprini, Stefano; Costa, Enrico; De Rosa, Alessandra; Del Monte, Ettore; Di Gesu, Laura; Di Lalla, Niccolo; Donnarumma, Immacolata; Dovciak, Michal R.; Ehlert, Steven; Enoto, Teruaki; Evangelista, Yuri; Fabiani, Sergio; Ferrazzoli, Riccardo A.; Garcia, Javier; Gunji, Shuichi; Hayashida, Kiyoshi; Iwakiri, Wataru G.; Jorstad, Svetlana; Kaaret, Philip; Karas, Vladimir; Kitaguchi, Takao J.; Kolodziejczak, Jeffery; Krawczynski, Henric; Latronico, Luca; Liodakis, Ioannis; Maldera, Simone; Manfreda, Alberto; Marin, Frederic; Marinucci, Andrea P.; Marscher, Alan; Matt, Giorgio; Mitsuishi, Ikuyuki; Mizuno, Tsunefumi; Negro, Michela; Ng, Chi-Yung L.; O'Dell, Stephen; Omodei, Nicola; Oppedisano, Chiara; Papitto, Alessandro G.; Pavlov, George L.; Peirson, Abel; Perri, Matteo; Pesce-Rollins, Melissa; Petrucci, Pierre-Olivier; Possenti, Andrea; Puccetti, Simonetta D.; Ramsey, Brian; Rankin, John; Ratheesh, Ajay J.; Roberts, Oliver W.; Romani, Roger; Sgro, Carmelo; Slane, Patrick; Soffitta, Paolo; Spandre, Gloria A.; Sunyaev, Rashid A.; Swartz, Douglas; Tamagawa, Toru; Tavecchio, Fabrizio; Tawara, Yuzuru F.; Tennant, Allyn E.; Thomas, Nicholas; Tombesi, Francesco; Trois, Alessio; Turolla, Roberto; Vink, Jacco C.; Weisskopf, Martin; Wu, Kinwah; Zane, Silvia; IXPE Collaboration.--This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited., The radiation from accreting X-ray pulsars was expected to be highly polarized, with some estimates for the polarization degree of up to 80%. However, phase-resolved and energy-resolved polarimetry of X-ray pulsars is required in order to test different models and to shed light on the emission processes and the geometry of the emission region. Here we present the first results of the observations of the accreting X-ray pulsar Vela X-1 performed with the Imaging X-ray Polarimetry Explorer. Vela X-1 is considered to be the archetypal example of a wind-accreting, high-mass X-ray binary system, consisting of a highly magnetized neutron star accreting matter from its supergiant stellar companion. The spectropolarimetric analysis of the phase-averaged data for Vela X-1 reveals a polarization degree (PD) of 2.3% ± 0.4% at the polarization angle (PA) of −47fdg3 ± 5fdg4. A low PD is consistent with the results obtained for other X-ray pulsars and is likely related to the inverse temperature structure of the neutron star atmosphere. The energy-resolved analysis shows the PD above 5 keV reaching 6%–10% and a ∼90° difference in the PA compared to the data in the 2–3 keV range. The phase-resolved spectropolarimetric analysis finds a PD in the range 0%–9% with the PA varying between −80° and 40°. © 2023. The Author(s). Published by the American Astronomical Society., The Imaging X-ray Polarimetry Explorer (IXPE) is a joint US and Italian mission. The US contribution is supported by the National Aeronautics and Space Administration (NASA) and led and managed by its Marshall Space Flight Center (MSFC), with industry partner Ball Aerospace (contract NNM15AA18C). The Italian contribution is supported by the Italian Space Agency (Agenzia Spaziale Italiana, ASI) through contract ASI-OHBI-2017-12-I.0, agreements ASI-INAF-2017-12-H0 and ASI-INFN-2017.13-H0, and its Space Science Data Center (SSDC) with agreements ASI-INAF-2022-14-HH.0 and ASI-INFN 2021-43-HH.0, and by the Istituto Nazionale di Astrofisica (INAF) and the Istituto Nazionale di Fisica Nucleare (INFN) in Italy. This research used data products provided by the IXPE Team (MSFC, SSDC, INAF, and INFN) and distributed with additional software tools by the High-Energy Astrophysics Science Archive Research Center (HEASARC), at NASA Goddard Space Flight Center (GSFC). We acknowledge support from the RSF grant 19-12-00423 (SST), the Academy of Finland grants 333112, 349144, 349373, and 349906 (JP, SST), the German Academic Exchange Service (DAAD) travel grant 57525212 (VD, VFS), and the German Research Foundation (DFG) grant WE 1312/53-1 (VFS)., With funding from the Spanish government through the "Severo Ochoa Centre of Excellence" accreditation (CEX2021-001131-S).

Published
2023
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2. X-ray polarization evidence for a 200-year-old flare of Sgr A .

Author

Marin F, Churazov E, Khabibullin I, Ferrazzoli R, Di Gesu L, Barnouin T, Di Marco A, Middei R, Vikhlinin A, Costa E, Soffitta P, Muleri F, Sunyaev R, Forman W, Kraft R, Bianchi S, Donnarumma I, Petrucci PO, Enoto T, Agudo I, Antonelli LA, Bachetti M, Baldini L, Baumgartner WH, Bellazzini R, Bongiorno SD, Bonino R, Brez A, Bucciantini N, Capitanio F, Castellano S, Cavazzuti E, Chen CT, Ciprini S, De Rosa A, Del Monte E, Di Lalla N, Doroshenko V, Dovčiak M, Ehlert SR, Evangelista Y, Fabiani S, Garcia JA, Gunji S, Hayashida K, Heyl J, Ingram A, Iwakiri W, Jorstad SG, Kaaret P, Karas V, Kitaguchi T, Kolodziejczak JJ, Krawczynski H, La Monaca F, Latronico L, Liodakis I, Maldera S, Manfreda A, Marinucci A, Marscher AP, Marshall HL, Massaro F, Matt G, Mitsuishi I, Mizuno T, Negro M, Ng CY, O'Dell SL, Omodei N, Oppedisano C, Papitto A, Pavlov GG, Peirson AL, Perri M, Pesce-Rollins M, Pilia M, Possenti A, Poutanen J, Puccetti S, Ramsey BD, Rankin J, Ratheesh A, Roberts OJ, Romani RW, Sgrò C, Slane P, Spandre G, Swartz D, Tamagawa T, Tavecchio F, Taverna R, Tawara Y, Tennant AF, Thomas NE, Tombesi F, Trois A, Tsygankov SS, Turolla R, Vink J, Weisskopf MC, Wu K, Xie F, and Zane S

Abstract

The centre of the Milky Way Galaxy hosts a black hole with a solar mass of about 4 million (Sagittarius A * (Sgr A)) that is very quiescent at present with a luminosity many orders of magnitude below those of active galactic nuclei 1 . Reflection of X-rays from Sgr A * by dense gas in the Galactic Centre region offers a means to study its past flaring activity on timescales of hundreds and thousands of years 2 . The shape of the X-ray continuum and the strong fluorescent iron line observed from giant molecular clouds in the vicinity of Sgr A * are consistent with the reflection scenario 3-5 . If this interpretation is correct, the reflected continuum emission should be polarized 6 . Here we report observations of polarized X-ray emission in the direction of the molecular clouds in the Galactic Centre using the Imaging X-ray Polarimetry Explorer. We measure a polarization degree of 31% ± 11%, and a polarization angle of -48° ± 11°. The polarization angle is consistent with Sgr A * being the primary source of the emission, and the polarization degree implies that some 200 years ago, the X-ray luminosity of Sgr A * was briefly comparable to that of a Seyfert galaxy., (© 2023. The Author(s), under exclusive licence to Springer Nature Limited.)

Published
2023
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3. Vela pulsar wind nebula X-rays are polarized to near the synchrotron limit.

Author

Xie F, Di Marco A, La Monaca F, Liu K, Muleri F, Bucciantini N, Romani RW, Costa E, Rankin J, Soffitta P, Bachetti M, Di Lalla N, Fabiani S, Ferrazzoli R, Gunji S, Latronico L, Negro M, Omodei N, Pilia M, Trois A, Watanabe E, Agudo I, Antonelli LA, Baldini L, Baumgartner WH, Bellazzini R, Bianchi S, Bongiorno SD, Bonino R, Brez A, Capitanio F, Castellano S, Cavazzuti E, Ciprini S, De Rosa A, Del Monte E, Di Gesu L, Donnarumma I, Doroshenko V, Dovčiak M, Ehlert SR, Enoto T, Evangelista Y, Garcia JA, Hayashida K, Heyl J, Iwakiri W, Jorstad SG, Karas V, Kitaguchi T, Kolodziejczak JJ, Krawczynski H, Liodakis I, Maldera S, Manfreda A, Marin F, Marinucci A, Marscher AP, Marshall HL, Massaro F, Matt G, Mitsuishi I, Mizuno T, Ng CY, O'Dell SL, Oppedisano C, Papitto A, Pavlov GG, Peirson AL, Perri M, Pesce-Rollins M, Petrucci PO, Possenti A, Poutanen J, Puccetti S, Ramsey BD, Ratheesh A, Sgró C, Slane P, Spandre G, Tamagawa T, Tavecchio F, Taverna R, Tawara Y, Tennant AF, Thomas NE, Tombesi F, Tsygankov SS, Turolla R, Vink J, Weisskopf MC, Wu K, and Zane S

Abstract

Pulsar wind nebulae are formed when outflows of relativistic electrons and positrons hit the surrounding supernova remnant or interstellar medium at a shock front. The Vela pulsar wind nebula is powered by a young pulsar (B0833-45, aged 11,000 years) 1 and located inside an extended structure called Vela X, which is itself inside the supernova remnant 2 . Previous X-ray observations revealed two prominent arcs that are bisected by a jet and counter jet 3,4 . Radio maps have shown high linear polarization of 60% in the outer regions of the nebula 5 . Here we report an X-ray observation of the inner part of the nebula, where polarization can exceed 60% at the leading edge-approaching the theoretical limit of what can be produced by synchrotron emission. We infer that, in contrast with the case of the supernova remnant, the electrons in the pulsar wind nebula are accelerated with little or no turbulence in a highly uniform magnetic field., (© 2022. The Author(s), under exclusive licence to Springer Nature Limited.)

Published
2022
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4. Polarized x-rays constrain the disk-jet geometry in the black hole x-ray binary Cygnus X-1.

Author

Krawczynski H, Muleri F, Dovčiak M, Veledina A, Rodriguez Cavero N, Svoboda J, Ingram A, Matt G, Garcia JA, Loktev V, Negro M, Poutanen J, Kitaguchi T, Podgorný J, Rankin J, Zhang W, Berdyugin A, Berdyugina SV, Bianchi S, Blinov D, Capitanio F, Di Lalla N, Draghis P, Fabiani S, Kagitani M, Kravtsov V, Kiehlmann S, Latronico L, Lutovinov AA, Mandarakas N, Marin F, Marinucci A, Miller JM, Mizuno T, Molkov SV, Omodei N, Petrucci PO, Ratheesh A, Sakanoi T, Semena AN, Skalidis R, Soffitta P, Tennant AF, Thalhammer P, Tombesi F, Weisskopf MC, Wilms J, Zhang S, Agudo I, Antonelli LA, Bachetti M, Baldini L, Baumgartner WH, Bellazzini R, Bongiorno SD, Bonino R, Brez A, Bucciantini N, Castellano S, Cavazzuti E, Ciprini S, Costa E, De Rosa A, Del Monte E, Di Gesu L, Di Marco A, Donnarumma I, Doroshenko V, Ehlert SR, Enoto T, Evangelista Y, Ferrazzoli R, Gunji S, Hayashida K, Heyl J, Iwakiri W, Jorstad SG, Karas V, Kolodziejczak JJ, La Monaca F, Liodakis I, Maldera S, Manfreda A, Marscher AP, Marshall HL, Mitsuishi I, Ng CY, O'Dell SL, Oppedisano C, Papitto A, Pavlov GG, Peirson AL, Perri M, Pesce-Rollins M, Pilia M, Possenti A, Puccetti S, Ramsey BD, Romani RW, Sgrò C, Slane P, Spandre G, Tamagawa T, Tavecchio F, Taverna R, Tawara Y, Thomas NE, Trois A, Tsygankov S, Turolla R, Vink J, Wu K, Xie F, and Zane S

Abstract

A black hole x-ray binary (XRB) system forms when gas is stripped from a normal star and accretes onto a black hole, which heats the gas sufficiently to emit x-rays. We report a polarimetric observation of the XRB Cygnus X-1 using the Imaging X-ray Polarimetry Explorer. The electric field position angle aligns with the outflowing jet, indicating that the jet is launched from the inner x-ray-emitting region. The polarization degree is 4.01 ± 0.20% at 2 to 8 kiloelectronvolts, implying that the accretion disk is viewed closer to edge-on than the binary orbit. These observations reveal that hot x-ray-emitting plasma is spatially extended in a plane perpendicular to, not parallel to, the jet axis.

Published
2022
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5. Polarized x-rays from a magnetar.

Author

Taverna R, Turolla R, Muleri F, Heyl J, Zane S, Baldini L, González-Caniulef D, Bachetti M, Rankin J, Caiazzo I, Di Lalla N, Doroshenko V, Errando M, Gau E, Kırmızıbayrak D, Krawczynski H, Negro M, Ng M, Omodei N, Possenti A, Tamagawa T, Uchiyama K, Weisskopf MC, Agudo I, Antonelli LA, Baumgartner WH, Bellazzini R, Bianchi S, Bongiorno SD, Bonino R, Brez A, Bucciantini N, Capitanio F, Castellano S, Cavazzuti E, Ciprini S, Costa E, De Rosa A, Del Monte E, Di Gesu L, Di Marco A, Donnarumma I, Dovčiak M, Ehlert SR, Enoto T, Evangelista Y, Fabiani S, Ferrazzoli R, Garcia JA, Gunji S, Hayashida K, Iwakiri W, Jorstad SG, Karas V, Kitaguchi T, Kolodziejczak JJ, La Monaca F, Latronico L, Liodakis I, Maldera S, Manfreda A, Marin F, Marinucci A, Marscher AP, Marshall HL, Matt G, Mitsuishi I, Mizuno T, Ng SC, O'Dell SL, Oppedisano C, Papitto A, Pavlov GG, Peirson AL, Perri M, Pesce-Rollins M, Pilia M, Poutanen J, Puccetti S, Ramsey BD, Ratheesh A, Romani RW, Sgrò C, Slane P, Soffitta P, Spandre G, Tavecchio F, Tawara Y, Tennant AF, Thomas NE, Tombesi F, Trois A, Tsygankov SS, Vink J, Wu K, and Xie F

Abstract

Magnetars are neutron stars with ultrastrong magnetic fields, which can be observed in x-rays. Polarization measurements could provide information on their magnetic fields and surface properties. We observed polarized x-rays from the magnetar 4U 0142+61 using the Imaging X-ray Polarimetry Explorer and found a linear polarization degree of 13.5 ± 0.8% averaged over the 2- to 8-kilo-electron volt band. The polarization changes with energy: The degree is 15.0 ± 1.0% at 2 to 4 kilo-electron volts, drops below the instrumental sensitivity ~4 to 5 kilo-electron volts, and rises to 35.2 ± 7.1% at 5.5 to 8 kilo-electron volts. The polarization angle also changes by 90° at ~4 to 5 kilo-electron volts. These results are consistent with a model in which thermal radiation from the magnetar surface is reprocessed by scattering off charged particles in the magnetosphere.

Published
2022
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6. Polarized blazar X-rays imply particle acceleration in shocks.

Author

Liodakis I, Marscher AP, Agudo I, Berdyugin AV, Bernardos MI, Bonnoli G, Borman GA, Casadio C, Casanova VC, Cavazzuti E, Rodriguez Cavero N, Di Gesu L, Di Lalla N, Donnarumma I, Ehlert SR, Errando M, Escudero J, Garcı A-Comas M, Agı S-González B, Husillos C, Jormanainen J, Jorstad SG, Kagitani M, Kopatskaya EN, Kravtsov V, Krawczynski H, Lindfors E, Larionova EG, Madejski GM, Marin F, Marchini A, Marshall HL, Morozova DA, Massaro F, Masiero JR, Mawet D, Middei R, Millar-Blanchaer MA, Myserlis I, Negro M, Nilsson K, O'Dell SL, Omodei N, Pacciani L, Paggi A, Panopoulou GV, Peirson AL, Perri M, Petrucci PO, Poutanen J, Puccetti S, Romani RW, Sakanoi T, Savchenko SS, Sota A, Tavecchio F, Tinyanont S, Vasilyev AA, Weaver ZR, Zhovtan AV, Antonelli LA, Bachetti M, Baldini L, Baumgartner WH, Bellazzini R, Bianchi S, Bongiorno SD, Bonino R, Brez A, Bucciantini N, Capitanio F, Castellano S, Ciprini S, Costa E, De Rosa A, Del Monte E, Di Marco A, Doroshenko V, Dovčiak M, Enoto T, Evangelista Y, Fabiani S, Ferrazzoli R, Garcia JA, Gunji S, Hayashida K, Heyl J, Iwakiri W, Karas V, Kitaguchi T, Kolodziejczak JJ, La Monaca F, Latronico L, Maldera S, Manfreda A, Marinucci A, Matt G, Mitsuishi I, Mizuno T, Muleri F, Ng SC, Oppedisano C, Papitto A, Pavlov GG, Pesce-Rollins M, Pilia M, Possenti A, Ramsey BD, Rankin J, Ratheesh A, Sgró C, Slane P, Soffitta P, Spandre G, Tamagawa T, Taverna R, Tawara Y, Tennant AF, Thomas NE, Tombesi F, Trois A, Tsygankov S, Turolla R, Vink J, Weisskopf MC, Wu K, Xie F, and Zane S

Abstract

Most of the light from blazars, active galactic nuclei with jets of magnetized plasma that point nearly along the line of sight, is produced by high-energy particles, up to around 1 TeV. Although the jets are known to be ultimately powered by a supermassive black hole, how the particles are accelerated to such high energies has been an unanswered question. The process must be related to the magnetic field, which can be probed by observations of the polarization of light from the jets. Measurements of the radio to optical polarization-the only range available until now-probe extended regions of the jet containing particles that left the acceleration site days to years earlier 1-3 , and hence do not directly explore the acceleration mechanism, as could X-ray measurements. Here we report the detection of X-ray polarization from the blazar Markarian 501 (Mrk 501). We measure an X-ray linear polarization degree Π X of around 10%, which is a factor of around 2 higher than the value at optical wavelengths, with a polarization angle parallel to the radio jet. This points to a shock front as the source of particle acceleration and also implies that the plasma becomes increasingly turbulent with distance from the shock., (© 2022. The Author(s).)

Published
2022
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7. Full-shell x-ray optics development at NASA Marshall Space Flight Center.

Author

Kilaru K, Ramsey BD, Baumgartner WH, Bongiorno SD, Broadway DM, Champey PR, Davis JM, O'Dell SL, Elsner RF, Gaskin JA, Johnson S, Kolodziejczak JK, Roberts OJ, Swartz DA, and Weisskopf MC

Abstract

NASA's Marshall Space Flight Center (MSFC) maintains an active research program toward the development of high-resolution, lightweight, grazing-incidence x-ray optics to serve the needs of future x-ray astronomy missions such as Lynx. MSFC development efforts include both direct fabrication (diamond turning and deterministic computer-controlled polishing) of mirror shells and replication of mirror shells (from figured, polished mandrels). Both techniques produce full-circumference monolithic (primary + secondary) shells that share the advantages of inherent stability, ease of assembly, and low production cost. However, to achieve high-angular resolution, MSFC is exploring significant technology advances needed to control sources of figure error including fabrication- and coating-induced stresses and mounting-induced distortions.

Published
2019
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