--- OA_place: publisher OA_type: diamond _id: '19283' abstract: - lang: eng text: "Context. The presence of dips in the gravity mode period spacing versus period diagram of γ Doradus stars is now well established thanks to recent asteroseismic studies. Such Lorentzian-shaped inertial dips arise from the interaction of gravito-inertial modes in the radiative envelope of intermediate-mass main sequence stars with pure inertial modes in their convective core, and allow us to study stellar internal properties. This window onto stellar internal dynamics is extremely valuable in the context of the understanding of angular-momentum transport inside stars, as it allows us to probe rotation in their core.\r\n\r\nAims. We investigate the signature and the detectability of a differential rotation between the convective core and the near-core region inside γ Doradus stars from the properties of inertial dips.\r\n\r\nMethods. We studied the coupling between gravito-inertial modes in the radiative zone and pure inertial modes in the convective core in the sub-inertial regime, allowing for a two-zone differential rotation from the two sides of the core-to-envelope boundary. We solved the coupling equation numerically and matched the result to an analytical derivation of the Lorentzian dip properties. We then used typical values of measured near-core rotation and buoyancy travel time to infer ranges of parameters for which differential core to near-core rotation would be detectable in current Kepler data.\r\n\r\nResults. We show that increasing the convective core rotation with respect to the near-core rotation leads to a shift of the period of the observed dip to lower periods. In addition, the dip gets deeper and thinner as the convective core rotation increases. We demonstrate that such a signature is detectable in Kepler data, given appropriate dip-parameter ranges and near-core structural properties.\r\n\r\nConclusions. Studying the dip properties in asteroseismic data thus allows us to access core to near-core radial differential rotation and to better understand the transport of angular momentum at convective–radiative interfaces in intermediate-mass main sequence stars." acknowledgement: 'We thank the referee for very constructive and detailed comments that led to an improvement of the quality of our study. L.B. and L.B. gratefully acknowledge support from the European Research Council (ERC) under the Horizon Europe programme (Calcifer; Starting Grant agreement N°101165631). S. Mathis acknowledges support from the PLATO CNES grant at CEA/DAp and from the European Research Council through HORIZON ERC SyG Grant 4D-STAR 101071505. While partially funded by the European Union, views and opinions expressed are however those of the author only and do not necessarily reflect those of the European Union or the European Research Council. Neither the European Union nor the granting authority can be held responsible for them. L. Barrault thanks the members of the asteroseismology group of the Institute of Astronomy (IvS) of KU Leuven, in particular T. Van Reeth, M. Vanrespaille, Z. Guo and C. Aerts, for their warm welcome during a work visit in Spring 2024, and very insightful input on the present study. The authors thank also the members of the Asteroseismology and Stellar Dynamics group of the Institute of Science and Technology Austria (ISTA) for very useful discussion: K. M. Smith, L. Einramhof, S. Torres and A. Cristea.' article_number: A225 article_processing_charge: Yes article_type: original author: - first_name: Lucas full_name: Barrault, Lucas id: 4471a8fd-32c1-11ee-a9a4-fb670d398f64 last_name: Barrault - first_name: S. full_name: Mathis, S. last_name: Mathis - first_name: Lisa Annabelle full_name: Bugnet, Lisa Annabelle id: d9edb345-f866-11ec-9b37-d119b5234501 last_name: Bugnet orcid: 0000-0003-0142-4000 citation: ama: Barrault L, Mathis S, Bugnet LA. Constraining differential rotation in γ Doradus stars from the properties of inertial dips. Astronomy & Astrophysics. 2025;694. doi:10.1051/0004-6361/202451541 apa: Barrault, L., Mathis, S., & Bugnet, L. A. (2025). Constraining differential rotation in γ Doradus stars from the properties of inertial dips. Astronomy & Astrophysics. EDP Sciences. https://doi.org/10.1051/0004-6361/202451541 chicago: Barrault, Lucas, S. Mathis, and Lisa Annabelle Bugnet. “Constraining Differential Rotation in γ Doradus Stars from the Properties of Inertial Dips.” Astronomy & Astrophysics. EDP Sciences, 2025. https://doi.org/10.1051/0004-6361/202451541. ieee: L. Barrault, S. Mathis, and L. A. Bugnet, “Constraining differential rotation in γ Doradus stars from the properties of inertial dips,” Astronomy & Astrophysics, vol. 694. EDP Sciences, 2025. ista: Barrault L, Mathis S, Bugnet LA. 2025. Constraining differential rotation in γ Doradus stars from the properties of inertial dips. Astronomy & Astrophysics. 694, A225. mla: Barrault, Lucas, et al. “Constraining Differential Rotation in γ Doradus Stars from the Properties of Inertial Dips.” Astronomy & Astrophysics, vol. 694, A225, EDP Sciences, 2025, doi:10.1051/0004-6361/202451541. short: L. Barrault, S. Mathis, L.A. Bugnet, Astronomy & Astrophysics 694 (2025). corr_author: '1' date_created: 2025-03-02T23:01:53Z date_published: 2025-02-01T00:00:00Z date_updated: 2026-02-16T12:09:14Z day: '01' ddc: - '520' department: - _id: LiBu doi: 10.1051/0004-6361/202451541 external_id: isi: - '001424452400025' file: - access_level: open_access checksum: 568a5e5951f20483663df145a780fc3d content_type: application/pdf creator: dernst date_created: 2025-03-04T09:57:03Z date_updated: 2025-03-04T09:57:03Z file_id: '19288' file_name: 2025_AstronomyAstrophysics_Barrault.pdf file_size: 7438476 relation: main_file success: 1 file_date_updated: 2025-03-04T09:57:03Z has_accepted_license: '1' intvolume: ' 694' isi: 1 language: - iso: eng month: '02' oa: 1 oa_version: Published Version project: - _id: 914d8549-16d5-11f0-9cad-bbe6324c93a9 grant_number: '101165631' name: 'Unveiling the mysteries of stellar dynamics: a pioneering journey in magnetoasteroseismology' publication: Astronomy & Astrophysics publication_identifier: eissn: - 1432-0746 issn: - 0004-6361 publication_status: published publisher: EDP Sciences quality_controlled: '1' scopus_import: '1' status: public title: Constraining differential rotation in γ Doradus stars from the properties of inertial dips tmp: image: /images/cc_by.png legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0) short: CC BY (4.0) type: journal_article user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 volume: 694 year: '2025' ... --- OA_place: publisher OA_type: diamond PlanS_conform: '1' _id: '20454' abstract: - lang: eng text: "Context. γ Dor stars are ideal targets for studies of the innermost dynamical properties of stars, due to their rich asteroseismic spectrum of gravity modes. Integrating internal magnetism to the picture appears as the next milestone of detailed asteroseismic studies, for its prime importance on stellar evolution. The inertial dip in prograde dipole modes period-spacing pattern of γ Dors stands out as a unique window on the convective core structure and dynamics. Recent studies have highlighted the dependence of the dip structure on core density stratification, the contrast of the near-core Brunt-Väisälä frequency and rotation rate, as well as the core-to-near-core differential rotation. In addition, the effect of envelope magnetism has been derived on low-frequency magneto-gravito-inertial waves.\r\n\r\nAims. We revisited the inertial dip formation including core and envelope magnetism, and explored the probing power of this feature on dynamo-generated core fields.\r\n\r\nMethods. We considered as a first step a toroidal magnetic field with a bi-layer (core and envelope) Alfvén frequency. This configuration allowed us to revisit the coupling problem using our knowledge on both core magneto-inertial modes and envelope magneto-gravito-inertial modes. Using this configuration, we were able to stay in an analytical framework to exhibit the magnetic effects on the inertial dip shape and location. This configuration allowed a laboratory to be set up that moves us towards the comprehension of magnetic effects on the dip structure.\r\n\r\nResults. We show a shift of the inertial dip towards lower spin parameter values and a thinner dip with increasing core magnetic field’s strength, quite similar to the signature of differential rotation. The magnetic effects become sizeable when the ratio of the magnetic to the Coriolis effects is high enough. We explored the potential degeneracy of the magnetic effects with differential rotation. We studied the detectability of core magnetism, considering both observational constraints on the periods of the modes and potential gravito-inertial mode suppression." acknowledgement: 'We thank the referee for their comments and suggestions which allowed us to improve the quality of this manuscript. L. Barrault and L. Bugnet gratefully acknowledge support from the European Research Council (ERC) under the Horizon Europe programme (Calcifer; Starting Grant agreement N°101165631). S. Mathis acknowledges support from the PLATO CNES grant at CEA/DAp. S. Mathis and J.S.G. Mombarg acknowledge support from the European Research Council through HORIZON ERC SyG Grant 4D-STAR 101071505. While partially funded by the European Union, views and opinions expressed are however those of the authors only and do not necessarily reflect those of the European Union or the European Research Council. Neither the European Union nor the granting authority can be held responsible for them. L. Barrault thanks T. Van Reeth and C. Aerts for their invaluable teachings. The authors thank also the members of the Asteroseismology and Stellar Dynamics group of the Institute of Science and Technology Austria (ISTA) for very useful discussion: A. Cristea, L. Einramhof, K. M. Smith, S. Torres.' article_number: A253 article_processing_charge: No article_type: original arxiv: 1 author: - first_name: Lucas full_name: Barrault, Lucas id: 4471a8fd-32c1-11ee-a9a4-fb670d398f64 last_name: Barrault - first_name: Lisa Annabelle full_name: Bugnet, Lisa Annabelle id: d9edb345-f866-11ec-9b37-d119b5234501 last_name: Bugnet orcid: 0000-0003-0142-4000 - first_name: S. full_name: Mathis, S. last_name: Mathis - first_name: J. S.G. full_name: Mombarg, J. S.G. last_name: Mombarg citation: ama: 'Barrault L, Bugnet LA, Mathis S, Mombarg JSG. Exploring the probing power of γ Dor’s inertial dip for core magnetism: The case of a toroidal field. Astronomy & Astrophysics. 2025;701. doi:10.1051/0004-6361/202555213' apa: 'Barrault, L., Bugnet, L. A., Mathis, S., & Mombarg, J. S. G. (2025). Exploring the probing power of γ Dor’s inertial dip for core magnetism: The case of a toroidal field. Astronomy & Astrophysics. EDP Sciences. https://doi.org/10.1051/0004-6361/202555213' chicago: 'Barrault, Lucas, Lisa Annabelle Bugnet, S. Mathis, and J. S.G. Mombarg. “Exploring the Probing Power of γ Dor’s Inertial Dip for Core Magnetism: The Case of a Toroidal Field.” Astronomy & Astrophysics. EDP Sciences, 2025. https://doi.org/10.1051/0004-6361/202555213.' ieee: 'L. Barrault, L. A. Bugnet, S. Mathis, and J. S. G. Mombarg, “Exploring the probing power of γ Dor’s inertial dip for core magnetism: The case of a toroidal field,” Astronomy & Astrophysics, vol. 701. EDP Sciences, 2025.' ista: 'Barrault L, Bugnet LA, Mathis S, Mombarg JSG. 2025. Exploring the probing power of γ Dor’s inertial dip for core magnetism: The case of a toroidal field. Astronomy & Astrophysics. 701, A253.' mla: 'Barrault, Lucas, et al. “Exploring the Probing Power of γ Dor’s Inertial Dip for Core Magnetism: The Case of a Toroidal Field.” Astronomy & Astrophysics, vol. 701, A253, EDP Sciences, 2025, doi:10.1051/0004-6361/202555213.' short: L. Barrault, L.A. Bugnet, S. Mathis, J.S.G. Mombarg, Astronomy & Astrophysics 701 (2025). corr_author: '1' date_created: 2025-10-12T22:01:26Z date_published: 2025-09-01T00:00:00Z date_updated: 2026-02-19T09:32:04Z day: '01' ddc: - '520' department: - _id: LiBu - _id: GradSch doi: 10.1051/0004-6361/202555213 external_id: arxiv: - '2507.00308' isi: - '001585834500002' file: - access_level: open_access checksum: 2c209b33119af4a251bab4a418a21075 content_type: application/pdf creator: dernst date_created: 2025-10-13T07:05:55Z date_updated: 2025-10-13T07:05:55Z file_id: '20459' file_name: 2025_AstronomyAstrophysics_BarraultL.pdf file_size: 2503149 relation: main_file success: 1 file_date_updated: 2025-10-13T07:05:55Z has_accepted_license: '1' intvolume: ' 701' isi: 1 language: - iso: eng month: '09' oa: 1 oa_version: Published Version project: - _id: 914d8549-16d5-11f0-9cad-bbe6324c93a9 grant_number: '101165631' name: 'Unveiling the mysteries of stellar dynamics: a pioneering journey in magnetoasteroseismology' publication: Astronomy & Astrophysics publication_identifier: eissn: - 1432-0746 issn: - 0004-6361 publication_status: published publisher: EDP Sciences quality_controlled: '1' scopus_import: '1' status: public title: 'Exploring the probing power of γ Dor''s inertial dip for core magnetism: The case of a toroidal field' tmp: image: /images/cc_by.png legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0) short: CC BY (4.0) type: journal_article user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 volume: 701 year: '2025' ...