Standard

High Optical-to-X-Ray Polarization Ratio Reveals Compton Scattering in BL Lacertae’s Jet. / Agudo, Iván; Liodakis, Ioannis; Otero-Santos, Jorge; Middei, Riccardo; Marscher, Alan; Jorstad, Svetlana; Zhang, Haocheng; Li, Hui; Di Gesu, Laura; Romani, Roger W.; Kim, Dawoon E.; Fenu, Francesco; Marshall, Herman L.; Pacciani, Luigi; Pedrosa, Juan Escudero; Aceituno, Francisco José; Agís-González, Beatriz; Bonnoli, Giacomo; Casanova, Víctor; Morcuende, Daniel; Piirola, Vilppu; Sota, Alfredo; Kouch, Pouya M.; Lindfors, Elina; McCall, Callum; Jermak, Helen E.; Steele, Iain A.; Borman, George A.; Grishina, Tatiana S.; Hagen-Thorn, Vladimir A.; Kopatskaya, Evgenia N.; Larionova, Elena G.; Morozova, Daria A.; Savchenko, Sergey S.; Shishkina, Ekaterina V.; Troitskiy, Ivan S.; Troitskaya, Yulia V.; Vasilyev, Andrey A.; Zhovtan, Alexey V.; Myserlis, Ioannis; Gurwell, Mark; Keating, Garrett; Rao, Ramprasad; Kang, Sincheol; Lee, Sang-Sung; Kim, Sanghyun; Cheong, Whee Yeon; Jeong, Hyeon-Woo; Angelakis, Emmanouil; Kraus, Alexander; Blinov, Dmitry; Maharana, Siddharth; Bachev, Rumen; Jormanainen, Jenni; Nilsson, Kari; Fallah Ramazani, Vandad; Casadio, Carolina; Fuentes, Antonio; Traianou, Efthalia; Thum, Clemens; Gómez, José L.; Antonelli, Lucio Angelo; Bachetti, Matteo; 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 Lalla, Niccolò; Di Marco, Alessandro; Donnarumma, Immacolata; Doroshenko, Victor; Dovčiak, Michal; Ehlert, Steven R.; Enoto, Teruaki; Evangelista, Yuri; Fabiani, Sergio; Ferrazzoli, Riccardo; García, Javier A.; Gunji, Shuichi; Hayashida, Kiyoshi; Heyl, Jeremy; Iwakiri, Wataru; Kaaret, Philip; Karas, Vladimir; Kislat, Fabian; Kitaguchi, Takao; Kolodziejczak, Jeffery J.; Krawczynski, Henric; La Monaca, Fabio; Latronico, Luca; Maldera, Simone; Manfreda, Alberto; Marin, Frédéric; Marinucci, Andrea; Massaro, Francesco; Matt, Giorgio; Mitsuishi, Ikuyuki; Mizuno, Tsunefumi; Muleri, Fabio; 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; Pilia, Maura; Possenti, Andrea; Poutanen, Juri; Puccetti, Simonetta; Ramsey, Brian D.; Rankin, John; Ratheesh, Ajay; Roberts, Oliver J.; Sgrò, Carmelo; Slane, Patrick; Soffitta, Paolo; Spandre, Gloria; Swartz, Douglas A.; Tamagawa, Toru; Tavecchio, Fabrizio; Taverna, Roberto; Tawara, Yuzuru; Tennant, Allyn F.; Thomas, Nicholas E.; Tombesi, Francesco; Trois, Alessio; Tsygankov, Sergey S.; Turolla, Roberto; Vink, Jacco; Weisskopf, Martin C.; Wu, Kinwah; Xie, Fei; Zane, Silvia.

в: Astrophysical Journal Letters, Том 985, № 1, L15, 16.05.2025.

Результаты исследований: Научные публикации в периодических изданияхстатьяРецензирование

Harvard

Agudo, I, Liodakis, I, Otero-Santos, J, Middei, R, Marscher, A, Jorstad, S, Zhang, H, Li, H, Di Gesu, L, Romani, RW, Kim, DE, Fenu, F, Marshall, HL, Pacciani, L, Pedrosa, JE, Aceituno, FJ, Agís-González, B, Bonnoli, G, Casanova, V, Morcuende, D, Piirola, V, Sota, A, Kouch, PM, Lindfors, E, McCall, C, Jermak, HE, Steele, IA, Borman, GA, Grishina, TS, Hagen-Thorn, VA, Kopatskaya, EN, Larionova, EG, Morozova, DA, Savchenko, SS, Shishkina, EV, Troitskiy, IS, Troitskaya, YV, Vasilyev, AA, Zhovtan, AV, Myserlis, I, Gurwell, M, Keating, G, Rao, R, Kang, S, Lee, S-S, Kim, S, Cheong, WY, Jeong, H-W, Angelakis, E, Kraus, A, Blinov, D, Maharana, S, Bachev, R, Jormanainen, J, Nilsson, K, Fallah Ramazani, V, Casadio, C, Fuentes, A, Traianou, E, Thum, C, Gómez, JL, Antonelli, LA, Bachetti, M, Baldini, L, Baumgartner, WH, Bellazzini, R, Bianchi, S, Bongiorno, SD, Bonino, R, Brez, A, Bucciantini, N, Capitanio, F, Castellano, S, Cavazzuti, E, Chen, C-T, Ciprini, S, Costa, E, De Rosa, A, Del Monte, E, Di Lalla, N, Di Marco, A, Donnarumma, I, Doroshenko, V, Dovčiak, M, Ehlert, SR, Enoto, T, Evangelista, Y, Fabiani, S, Ferrazzoli, R, García, JA, Gunji, S, Hayashida, K, Heyl, J, Iwakiri, W, Kaaret, P, Karas, V, Kislat, F, Kitaguchi, T, Kolodziejczak, JJ, Krawczynski, H, La Monaca, F, Latronico, L, Maldera, S, Manfreda, A, Marin, F, Marinucci, A, Massaro, F, Matt, G, Mitsuishi, I, Mizuno, T, Muleri, F, Negro, M, Ng, C-Y, O’Dell, SL, Omodei, N, Oppedisano, C, Papitto, A, Pavlov, GG, Peirson, AL, Perri, M, Pesce-Rollins, M, Petrucci, P-O, Pilia, M, Possenti, A, Poutanen, J, Puccetti, S, Ramsey, BD, Rankin, J, Ratheesh, A, Roberts, OJ, Sgrò, C, Slane, P, Soffitta, P, Spandre, G, Swartz, DA, 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 & Zane, S 2025, 'High Optical-to-X-Ray Polarization Ratio Reveals Compton Scattering in BL Lacertae’s Jet', Astrophysical Journal Letters, Том. 985, № 1, L15. https://doi.org/10.3847/2041-8213/adc572

APA

Agudo, I., Liodakis, I., Otero-Santos, J., Middei, R., Marscher, A., Jorstad, S., Zhang, H., Li, H., Di Gesu, L., Romani, R. W., Kim, D. E., Fenu, F., Marshall, H. L., Pacciani, L., Pedrosa, J. E., Aceituno, F. J., Agís-González, B., Bonnoli, G., Casanova, V., ... Zane, S. (2025). High Optical-to-X-Ray Polarization Ratio Reveals Compton Scattering in BL Lacertae’s Jet. Astrophysical Journal Letters, 985(1), [L15]. https://doi.org/10.3847/2041-8213/adc572

Vancouver

Agudo I, Liodakis I, Otero-Santos J, Middei R, Marscher A, Jorstad S и пр. High Optical-to-X-Ray Polarization Ratio Reveals Compton Scattering in BL Lacertae’s Jet. Astrophysical Journal Letters. 2025 Май 16;985(1). L15. https://doi.org/10.3847/2041-8213/adc572

Author

Agudo, Iván ; Liodakis, Ioannis ; Otero-Santos, Jorge ; Middei, Riccardo ; Marscher, Alan ; Jorstad, Svetlana ; Zhang, Haocheng ; Li, Hui ; Di Gesu, Laura ; Romani, Roger W. ; Kim, Dawoon E. ; Fenu, Francesco ; Marshall, Herman L. ; Pacciani, Luigi ; Pedrosa, Juan Escudero ; Aceituno, Francisco José ; Agís-González, Beatriz ; Bonnoli, Giacomo ; Casanova, Víctor ; Morcuende, Daniel ; Piirola, Vilppu ; Sota, Alfredo ; Kouch, Pouya M. ; Lindfors, Elina ; McCall, Callum ; Jermak, Helen E. ; Steele, Iain A. ; Borman, George A. ; Grishina, Tatiana S. ; Hagen-Thorn, Vladimir A. ; Kopatskaya, Evgenia N. ; Larionova, Elena G. ; Morozova, Daria A. ; Savchenko, Sergey S. ; Shishkina, Ekaterina V. ; Troitskiy, Ivan S. ; Troitskaya, Yulia V. ; Vasilyev, Andrey A. ; Zhovtan, Alexey V. ; Myserlis, Ioannis ; Gurwell, Mark ; Keating, Garrett ; Rao, Ramprasad ; Kang, Sincheol ; Lee, Sang-Sung ; Kim, Sanghyun ; Cheong, Whee Yeon ; Jeong, Hyeon-Woo ; Angelakis, Emmanouil ; Kraus, Alexander ; Blinov, Dmitry ; Maharana, Siddharth ; Bachev, Rumen ; Jormanainen, Jenni ; Nilsson, Kari ; Fallah Ramazani, Vandad ; Casadio, Carolina ; Fuentes, Antonio ; Traianou, Efthalia ; Thum, Clemens ; Gómez, José L. ; Antonelli, Lucio Angelo ; Bachetti, Matteo ; 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 Lalla, Niccolò ; Di Marco, Alessandro ; Donnarumma, Immacolata ; Doroshenko, Victor ; Dovčiak, Michal ; Ehlert, Steven R. ; Enoto, Teruaki ; Evangelista, Yuri ; Fabiani, Sergio ; Ferrazzoli, Riccardo ; García, Javier A. ; Gunji, Shuichi ; Hayashida, Kiyoshi ; Heyl, Jeremy ; Iwakiri, Wataru ; Kaaret, Philip ; Karas, Vladimir ; Kislat, Fabian ; Kitaguchi, Takao ; Kolodziejczak, Jeffery J. ; Krawczynski, Henric ; La Monaca, Fabio ; Latronico, Luca ; Maldera, Simone ; Manfreda, Alberto ; Marin, Frédéric ; Marinucci, Andrea ; Massaro, Francesco ; Matt, Giorgio ; Mitsuishi, Ikuyuki ; Mizuno, Tsunefumi ; Muleri, Fabio ; 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 ; Pilia, Maura ; Possenti, Andrea ; Poutanen, Juri ; Puccetti, Simonetta ; Ramsey, Brian D. ; Rankin, John ; Ratheesh, Ajay ; Roberts, Oliver J. ; Sgrò, Carmelo ; Slane, Patrick ; Soffitta, Paolo ; Spandre, Gloria ; Swartz, Douglas A. ; Tamagawa, Toru ; Tavecchio, Fabrizio ; Taverna, Roberto ; Tawara, Yuzuru ; Tennant, Allyn F. ; Thomas, Nicholas E. ; Tombesi, Francesco ; Trois, Alessio ; Tsygankov, Sergey S. ; Turolla, Roberto ; Vink, Jacco ; Weisskopf, Martin C. ; Wu, Kinwah ; Xie, Fei ; Zane, Silvia. / High Optical-to-X-Ray Polarization Ratio Reveals Compton Scattering in BL Lacertae’s Jet. в: Astrophysical Journal Letters. 2025 ; Том 985, № 1.

BibTeX

@article{2f31cd43e691420b90b65de06db4c7b7,
title = "High Optical-to-X-Ray Polarization Ratio Reveals Compton Scattering in BL Lacertae{\textquoteright}s Jet",
abstract = "Blazars, supermassive black hole systems with highly relativistic jets aligned with the line of sight, are the most powerful long-lived emitters of electromagnetic emission in the Universe. We report here on a radio-to-gamma-ray multiwavelength campaign on the blazar BL Lacertae with unprecedented polarimetric coverage from radio to X-ray wavelengths. The observations caught an extraordinary event on 2023 November 10–18, when the degree of linear polarization of optical synchrotron radiation reached a record value of 47.5%. In stark contrast, the Imaging X-ray Polarimetry Explorer found that the X-ray (Compton scattering or hadron-induced) emission was polarized at less than 7.4% (3σ confidence level). We argue here that this observational result rules out a hadronic origin of the high-energy emission and strongly favors a leptonic (Compton scattering) origin, thereby breaking the degeneracy between hadronic and leptonic emission models for BL Lacertae and demonstrating the power of multiwavelength polarimetry to address this question. Furthermore, the multiwavelength flux and polarization variability, featuring an extremely prominent rise and decay of the optical polarization degree, is interpreted for the first time by the relaxation of a magnetic “spring” embedded in the newly injected plasma. This suggests that the plasma jet can maintain a predominant toroidal magnetic field component parsecs away from the central engine.",
author = "Iv{\'a}n Agudo and Ioannis Liodakis and Jorge Otero-Santos and Riccardo Middei and Alan Marscher and Svetlana Jorstad and Haocheng Zhang and Hui Li and {Di Gesu}, Laura and Romani, {Roger W.} and Kim, {Dawoon E.} and Francesco Fenu and Marshall, {Herman L.} and Luigi Pacciani and Pedrosa, {Juan Escudero} and Aceituno, {Francisco Jos{\'e}} and Beatriz Ag{\'i}s-Gonz{\'a}lez and Giacomo Bonnoli and V{\'i}ctor Casanova and Daniel Morcuende and Vilppu Piirola and Alfredo Sota and Kouch, {Pouya M.} and Elina Lindfors and Callum McCall and Jermak, {Helen E.} and Steele, {Iain A.} and Borman, {George A.} and Grishina, {Tatiana S.} and Hagen-Thorn, {Vladimir A.} and Kopatskaya, {Evgenia N.} and Larionova, {Elena G.} and Morozova, {Daria A.} and Savchenko, {Sergey S.} and Shishkina, {Ekaterina V.} and Troitskiy, {Ivan S.} and Troitskaya, {Yulia V.} and Vasilyev, {Andrey A.} and Zhovtan, {Alexey V.} and Ioannis Myserlis and Mark Gurwell and Garrett Keating and Ramprasad Rao and Sincheol Kang and Sang-Sung Lee and Sanghyun Kim and Cheong, {Whee Yeon} and Hyeon-Woo Jeong and Emmanouil Angelakis and Alexander Kraus and Dmitry Blinov and Siddharth Maharana and Rumen Bachev and Jenni Jormanainen and Kari Nilsson and {Fallah Ramazani}, Vandad and Carolina Casadio and Antonio Fuentes and Efthalia Traianou and Clemens Thum and G{\'o}mez, {Jos{\'e} L.} and Antonelli, {Lucio Angelo} and Matteo Bachetti and Luca Baldini and Baumgartner, {Wayne H.} and Ronaldo Bellazzini and Stefano Bianchi and Bongiorno, {Stephen D.} and Raffaella Bonino and Alessandro Brez and Niccol{\`o} Bucciantini and Fiamma Capitanio and Simone Castellano and Elisabetta Cavazzuti and Chien-Ting Chen and Stefano Ciprini and Enrico Costa and {De Rosa}, Alessandra and {Del Monte}, Ettore and {Di Lalla}, Niccol{\`o} and {Di Marco}, Alessandro and Immacolata Donnarumma and Victor Doroshenko and Michal Dov{\v c}iak and Ehlert, {Steven R.} and Teruaki Enoto and Yuri Evangelista and Sergio Fabiani and Riccardo Ferrazzoli and Garc{\'i}a, {Javier A.} and Shuichi Gunji and Kiyoshi Hayashida and Jeremy Heyl and Wataru Iwakiri and Philip Kaaret and Vladimir Karas and Fabian Kislat and Takao Kitaguchi and Kolodziejczak, {Jeffery J.} and Henric Krawczynski and {La Monaca}, Fabio and Luca Latronico and Simone Maldera and Alberto Manfreda and Fr{\'e}d{\'e}ric Marin and Andrea Marinucci and Francesco Massaro and Giorgio Matt and Ikuyuki Mitsuishi and Tsunefumi Mizuno and Fabio Muleri and Michela Negro and Chi-Yung Ng and O{\textquoteright}Dell, {Stephen L.} and Nicola Omodei and Chiara Oppedisano and Alessandro Papitto and Pavlov, {George G.} and Peirson, {Abel L.} and Matteo Perri and Melissa Pesce-Rollins and Pierre-Olivier Petrucci and Maura Pilia and Andrea Possenti and Juri Poutanen and Simonetta Puccetti and Ramsey, {Brian D.} and John Rankin and Ajay Ratheesh and Roberts, {Oliver J.} and Carmelo Sgr{\`o} and Patrick Slane and Paolo Soffitta and Gloria Spandre and Swartz, {Douglas A.} and Toru Tamagawa and Fabrizio Tavecchio and Roberto Taverna and Yuzuru Tawara and Tennant, {Allyn F.} and Thomas, {Nicholas E.} and Francesco Tombesi and Alessio Trois and Tsygankov, {Sergey S.} and Roberto Turolla and Jacco Vink and Weisskopf, {Martin C.} and Kinwah Wu and Fei Xie and Silvia Zane",
year = "2025",
month = may,
day = "16",
doi = "10.3847/2041-8213/adc572",
language = "English",
volume = "985",
journal = "Astrophysical Journal Letters",
issn = "2041-8205",
publisher = "IOP Publishing Ltd.",
number = "1",

}

RIS

TY - JOUR

T1 - High Optical-to-X-Ray Polarization Ratio Reveals Compton Scattering in BL Lacertae’s Jet

AU - Agudo, Iván

AU - Liodakis, Ioannis

AU - Otero-Santos, Jorge

AU - Middei, Riccardo

AU - Marscher, Alan

AU - Jorstad, Svetlana

AU - Zhang, Haocheng

AU - Li, Hui

AU - Di Gesu, Laura

AU - Romani, Roger W.

AU - Kim, Dawoon E.

AU - Fenu, Francesco

AU - Marshall, Herman L.

AU - Pacciani, Luigi

AU - Pedrosa, Juan Escudero

AU - Aceituno, Francisco José

AU - Agís-González, Beatriz

AU - Bonnoli, Giacomo

AU - Casanova, Víctor

AU - Morcuende, Daniel

AU - Piirola, Vilppu

AU - Sota, Alfredo

AU - Kouch, Pouya M.

AU - Lindfors, Elina

AU - McCall, Callum

AU - Jermak, Helen E.

AU - Steele, Iain A.

AU - Borman, George A.

AU - Grishina, Tatiana S.

AU - Hagen-Thorn, Vladimir A.

AU - Kopatskaya, Evgenia N.

AU - Larionova, Elena G.

AU - Morozova, Daria A.

AU - Savchenko, Sergey S.

AU - Shishkina, Ekaterina V.

AU - Troitskiy, Ivan S.

AU - Troitskaya, Yulia V.

AU - Vasilyev, Andrey A.

AU - Zhovtan, Alexey V.

AU - Myserlis, Ioannis

AU - Gurwell, Mark

AU - Keating, Garrett

AU - Rao, Ramprasad

AU - Kang, Sincheol

AU - Lee, Sang-Sung

AU - Kim, Sanghyun

AU - Cheong, Whee Yeon

AU - Jeong, Hyeon-Woo

AU - Angelakis, Emmanouil

AU - Kraus, Alexander

AU - Blinov, Dmitry

AU - Maharana, Siddharth

AU - Bachev, Rumen

AU - Jormanainen, Jenni

AU - Nilsson, Kari

AU - Fallah Ramazani, Vandad

AU - Casadio, Carolina

AU - Fuentes, Antonio

AU - Traianou, Efthalia

AU - Thum, Clemens

AU - Gómez, José L.

AU - Antonelli, Lucio Angelo

AU - Bachetti, Matteo

AU - Baldini, Luca

AU - Baumgartner, Wayne H.

AU - Bellazzini, Ronaldo

AU - Bianchi, Stefano

AU - Bongiorno, Stephen D.

AU - Bonino, Raffaella

AU - Brez, Alessandro

AU - Bucciantini, Niccolò

AU - Capitanio, Fiamma

AU - Castellano, Simone

AU - Cavazzuti, Elisabetta

AU - Chen, Chien-Ting

AU - Ciprini, Stefano

AU - Costa, Enrico

AU - De Rosa, Alessandra

AU - Del Monte, Ettore

AU - Di Lalla, Niccolò

AU - Di Marco, Alessandro

AU - Donnarumma, Immacolata

AU - Doroshenko, Victor

AU - Dovčiak, Michal

AU - Ehlert, Steven R.

AU - Enoto, Teruaki

AU - Evangelista, Yuri

AU - Fabiani, Sergio

AU - Ferrazzoli, Riccardo

AU - García, Javier A.

AU - Gunji, Shuichi

AU - Hayashida, Kiyoshi

AU - Heyl, Jeremy

AU - Iwakiri, Wataru

AU - Kaaret, Philip

AU - Karas, Vladimir

AU - Kislat, Fabian

AU - Kitaguchi, Takao

AU - Kolodziejczak, Jeffery J.

AU - Krawczynski, Henric

AU - La Monaca, Fabio

AU - Latronico, Luca

AU - Maldera, Simone

AU - Manfreda, Alberto

AU - Marin, Frédéric

AU - Marinucci, Andrea

AU - Massaro, Francesco

AU - Matt, Giorgio

AU - Mitsuishi, Ikuyuki

AU - Mizuno, Tsunefumi

AU - Muleri, Fabio

AU - Negro, Michela

AU - Ng, Chi-Yung

AU - O’Dell, Stephen L.

AU - Omodei, Nicola

AU - Oppedisano, Chiara

AU - Papitto, Alessandro

AU - Pavlov, George G.

AU - Peirson, Abel L.

AU - Perri, Matteo

AU - Pesce-Rollins, Melissa

AU - Petrucci, Pierre-Olivier

AU - Pilia, Maura

AU - Possenti, Andrea

AU - Poutanen, Juri

AU - Puccetti, Simonetta

AU - Ramsey, Brian D.

AU - Rankin, John

AU - Ratheesh, Ajay

AU - Roberts, Oliver J.

AU - Sgrò, Carmelo

AU - Slane, Patrick

AU - Soffitta, Paolo

AU - Spandre, Gloria

AU - Swartz, Douglas A.

AU - Tamagawa, Toru

AU - Tavecchio, Fabrizio

AU - Taverna, Roberto

AU - Tawara, Yuzuru

AU - Tennant, Allyn F.

AU - Thomas, Nicholas E.

AU - Tombesi, Francesco

AU - Trois, Alessio

AU - Tsygankov, Sergey S.

AU - Turolla, Roberto

AU - Vink, Jacco

AU - Weisskopf, Martin C.

AU - Wu, Kinwah

AU - Xie, Fei

AU - Zane, Silvia

PY - 2025/5/16

Y1 - 2025/5/16

N2 - Blazars, supermassive black hole systems with highly relativistic jets aligned with the line of sight, are the most powerful long-lived emitters of electromagnetic emission in the Universe. We report here on a radio-to-gamma-ray multiwavelength campaign on the blazar BL Lacertae with unprecedented polarimetric coverage from radio to X-ray wavelengths. The observations caught an extraordinary event on 2023 November 10–18, when the degree of linear polarization of optical synchrotron radiation reached a record value of 47.5%. In stark contrast, the Imaging X-ray Polarimetry Explorer found that the X-ray (Compton scattering or hadron-induced) emission was polarized at less than 7.4% (3σ confidence level). We argue here that this observational result rules out a hadronic origin of the high-energy emission and strongly favors a leptonic (Compton scattering) origin, thereby breaking the degeneracy between hadronic and leptonic emission models for BL Lacertae and demonstrating the power of multiwavelength polarimetry to address this question. Furthermore, the multiwavelength flux and polarization variability, featuring an extremely prominent rise and decay of the optical polarization degree, is interpreted for the first time by the relaxation of a magnetic “spring” embedded in the newly injected plasma. This suggests that the plasma jet can maintain a predominant toroidal magnetic field component parsecs away from the central engine.

AB - Blazars, supermassive black hole systems with highly relativistic jets aligned with the line of sight, are the most powerful long-lived emitters of electromagnetic emission in the Universe. We report here on a radio-to-gamma-ray multiwavelength campaign on the blazar BL Lacertae with unprecedented polarimetric coverage from radio to X-ray wavelengths. The observations caught an extraordinary event on 2023 November 10–18, when the degree of linear polarization of optical synchrotron radiation reached a record value of 47.5%. In stark contrast, the Imaging X-ray Polarimetry Explorer found that the X-ray (Compton scattering or hadron-induced) emission was polarized at less than 7.4% (3σ confidence level). We argue here that this observational result rules out a hadronic origin of the high-energy emission and strongly favors a leptonic (Compton scattering) origin, thereby breaking the degeneracy between hadronic and leptonic emission models for BL Lacertae and demonstrating the power of multiwavelength polarimetry to address this question. Furthermore, the multiwavelength flux and polarization variability, featuring an extremely prominent rise and decay of the optical polarization degree, is interpreted for the first time by the relaxation of a magnetic “spring” embedded in the newly injected plasma. This suggests that the plasma jet can maintain a predominant toroidal magnetic field component parsecs away from the central engine.

UR - http://arxiv.org/abs/2505.01832 http://dx.doi.org/10.3847/2041-8213/adc572

UR - https://www.mendeley.com/catalogue/095808d9-9869-3bae-baee-fefb230c2071/

U2 - 10.3847/2041-8213/adc572

DO - 10.3847/2041-8213/adc572

M3 - Article

VL - 985

JO - Astrophysical Journal Letters

JF - Astrophysical Journal Letters

SN - 2041-8205

IS - 1

M1 - L15

ER -

ID: 135564963