%A HL Marshall %A I Liodakis %A AP Marscher %A N Di Lalla %A SG Jorstad %A DE Kim %A R Middei %A M Negro %A N Omodei %A AL Peirson %A M Perri %A S Puccetti %A M Laurenti %A I Agudo %A G Bonnoli %A AV Berdyugin %A E Cavazzuti %A N Rodriguez Cavero %A I Donnarumma %A L Di Gesu %A J Jormanainen %A H Krawczynski %A E Lindfors %A G Madjeski %A F Marin %A F Massaro %A L Pacciani %A J Poutanen %A F Tavecchio %A PM Kouch %A FJ Aceituno %A MI Bernardos %A V Casanova %A M GarcÃa-Comas %A B AgÃs-González %A C Husillos %A A Marchini %A A Sota %A D Blinov %A IG Bourbah %A S Kielhmann %A E Kontopodis %A N Mandarakas %A S Romanopoulos %A R Skalidis %A A Vervelaki %A GA Borman %A EN Kopatskaya %A EG Larionova %A DA Morozova %A SS Savchenko %A AA Vasilyev %A AV Zhovtan %A C Casadio %A J Escudero %A J Kramer %A I Myserlis %A E Trainou %A R Imazawa %A M Sasada %A Y Fukazawa %A KS Kawabata %A M Uemura %A T Mizuno %A T Nakaoka %A H Akitaya %A JR Masiero %A D Mawet %A GV Panopoulou %A S Tinyanont %A M Kagitani %A V Kravtsov %A T Sakanoi %A M Dattolo %A M Gurwell %A G Keating %A R Rao %A WY Cheong %A HW Jeong %A S Kang %A SH Kim %A SS Lee %A E Angelakis %A A Kraus %A A Hales %A S Kameno %A R Kneissl %A H Messias %A H Nagai %A LA Antonelli %A M Bachetti %A L Baldini %A WH Baumgartner %A R Bellazzini %A S Bianchi %A SD Bongiorno %A R Bonino %A A Brez %A N Bucciantini %A F Capitanio %V 972 %T Observations of Low and Intermediate Spectral Peak Blazars with the Imaging X-Ray Polarimetry Explorer %N 1 %D 2024 %I American Astronomical Society %L discovery10197388 %J The Astrophysical Journal %X We present X-ray polarimetry observations from the Imaging X-ray Polarimetry Explorer (IXPE) of three low spectral peak and one intermediate spectral peak blazars, namely 3C 273, 3C 279, 3C 454.3, and S5 0716+714. For none of these objects was IXPE able to detect X-ray polarization at the 3σ level. However, we placed upper limits on the polarization degree at ∼10%-30%. The undetected polarizations favor models where the X-ray band is dominated by unpolarized photons upscattered by relativistic electrons in the jets of blazars, although hadronic models are not completely eliminated. We discuss the X-ray polarization upper limits in the context of our contemporaneous multiwavelength polarization campaigns. %O Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence, https://creativecommons.org/licenses/by/4.0/. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.