{"publication":"The Astrophysical Journal","researchdata_availability":"no","article_number":"28","title":"Detection of knots in the type Iax supernova remnant Pa 30","day":"10","fulldoi":"https://doi.org/10.3847/1538-4357/ae9cb2","date_published":"2026-10-10T00:00:00Z","oa":1,"publication_identifier":{"eissn":["1538-4357"],"issn":["0004-637X"]},"user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","scopus_import":"1","tmp":{"name":"Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)","legal_code_url":"https://creativecommons.org/licenses/by/4.0/legalcode","image":"/images/cc_by.png","short":"CC BY (4.0)"},"corr_author":"1","article_type":"original","_id":"23151","oa_version":"Published Version","year":"2026","arxiv":1,"language":[{"iso":"eng"}],"PlanS_conform":"1","acknowledgement":"We thank Jim Fuller, SR Kulkarni, David Charbonneau, Paul Duffell, Abigail Polin, Miranda Pikus, Tony Piro, Lars Bildsten, Eliot Quartert, and Rob Fesen for helpful discussions. This work was supported by NASA through the NASA Hubble Fellowship grant HST-HF2-51527.001-A awarded by the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., for NASA, under contract NAS5-26555.\r\n\r\nFacility: Gemini:Gillett (GMOS-N) - .\r\n\r\nSoftware: astropy (Astropy Collaboration et al. 2013, 2018), scipy (P. Virtanen et al. 2020), emcee (D. Foreman-Mackey et al. 2013), DRAGONS (K. Labrie et al. 2023), DS9 (W. A. Joye & E. Mandel 2003).","DOAJ_listed":"1","volume":1010,"type":"journal_article","file":[{"date_created":"2026-10-19T06:57:17Z","success":1,"checksum":"a31da77f9197b832da52caf1417a87de","access_level":"open_access","content_type":"application/pdf","file_size":34494943,"creator":"dernst","file_name":"2026_AstrophysicalJour_Cunningham.pdf","relation":"main_file","date_updated":"2026-10-19T06:57:17Z","file_id":"23163"}],"external_id":{"arxiv":["2610.06424"]},"supplementarymaterial":"yes","quality_controlled":"1","OA_place":"publisher","status":"public","date_created":"2026-10-18T22:01:51Z","das_tickbox":"0","OA_type":"gold","issue":"1","date_updated":"2026-10-19T06:59:28Z","publication_status":"published","month":"10","has_accepted_license":"1","publisher":"IOP Publishing","department":[{"_id":"IlCa"}],"file_date_updated":"2026-10-19T06:57:17Z","article_processing_charge":"Yes","abstract":[{"lang":"eng","text":"We present deep, narrowband Gemini North/GMOS images of the Pa 30 nebula that reveal rich small-scale\r\nstructure in the ejecta filaments. In [S II], the number of detected filaments increases by about an order of\r\nmagnitude compared to previous studies. The imaging further reveals that the filaments are not smooth radial\r\nstreaks, but instead are composed of cascades of knots or clumps. The images in [O III] yield the first confirmation\r\nthat previously detected diffuse [O III] emission in fact originates from the same [S II] filaments. We measure a\r\nnebula center consistent with the position of the central star, indicating that the remnant has not received a large\r\ntransverse kick. The 3σ upper limit on the velocity of the stellar kick is ≲100 km s\r\n−1\r\n. Cross-sectional profiles of\r\nthe filaments in [S II] and [O III] show a central peak on top of a nebula background, the latter being likely due to\r\ndiffuse emission or unresolved filaments. The median [S II] width of 0.7 is slightly broader than the 0.50 seeing,\r\nproviding some evidence of partially resolved filaments and implying a characteristic knot diameter of ∼1016 cm.\r\nThe ≈1″ widths measured in [O III] are consistent with the poorer seeing of the oxygen images. The discovery of\r\nthis clumpy substructure provides a new observational constraint on models for the origin and evolution of the\r\nremarkable filamentary ejecta of Pa 30."}],"license":"https://creativecommons.org/licenses/by/4.0/","citation":{"mla":"Cunningham, Tim, et al. “Detection of Knots in the Type Iax Supernova Remnant Pa 30.” <i>The Astrophysical Journal</i>, vol. 1010, no. 1, 28, IOP Publishing, 2026, doi:<a href=\"https://doi.org/10.3847/1538-4357/ae9cb2\">10.3847/1538-4357/ae9cb2</a>.","chicago":"Cunningham, Tim, Ilaria Caiazzo, John C. Raymond, and Scott J. Kenyon. “Detection of Knots in the Type Iax Supernova Remnant Pa 30.” <i>The Astrophysical Journal</i>. IOP Publishing, 2026. <a href=\"https://doi.org/10.3847/1538-4357/ae9cb2\">https://doi.org/10.3847/1538-4357/ae9cb2</a>.","apa":"Cunningham, T., Caiazzo, I., Raymond, J. C., &#38; Kenyon, S. J. (2026). Detection of knots in the type Iax supernova remnant Pa 30. <i>The Astrophysical Journal</i>. IOP Publishing. <a href=\"https://doi.org/10.3847/1538-4357/ae9cb2\">https://doi.org/10.3847/1538-4357/ae9cb2</a>","ieee":"T. Cunningham, I. Caiazzo, J. C. Raymond, and S. J. Kenyon, “Detection of knots in the type Iax supernova remnant Pa 30,” <i>The Astrophysical Journal</i>, vol. 1010, no. 1. IOP Publishing, 2026.","ama":"Cunningham T, Caiazzo I, Raymond JC, Kenyon SJ. Detection of knots in the type Iax supernova remnant Pa 30. <i>The Astrophysical Journal</i>. 2026;1010(1). doi:<a href=\"https://doi.org/10.3847/1538-4357/ae9cb2\">10.3847/1538-4357/ae9cb2</a>","short":"T. Cunningham, I. Caiazzo, J.C. Raymond, S.J. Kenyon, The Astrophysical Journal 1010 (2026).","ista":"Cunningham T, Caiazzo I, Raymond JC, Kenyon SJ. 2026. Detection of knots in the type Iax supernova remnant Pa 30. The Astrophysical Journal. 1010(1), 28."},"ddc":["520"],"intvolume":"      1010","doi":"10.3847/1538-4357/ae9cb2","author":[{"last_name":"Cunningham","full_name":"Cunningham, Tim","first_name":"Tim"},{"orcid":"0000-0002-4770-5388","id":"8ae5b6e7-2a03-11ee-914d-b58ed7a3b47d","last_name":"Caiazzo","first_name":"Ilaria","full_name":"Caiazzo, Ilaria"},{"last_name":"Raymond","full_name":"Raymond, John C.","first_name":"John C."},{"last_name":"Kenyon","first_name":"Scott J.","full_name":"Kenyon, Scott J."}]}