Nested, asymmetric H-He circumstellar shells in the Type Icn/Ibn SN 2024abvb

Abstract

Interacting transients probe mass loss in the final stages of stellar evolution; however, the geometry and timing of multi-episode mass loss remain poorly constrained. SN 2024abvb is a nearby interacting event with transitional Ibn/Icn spectroscopic properties and multi-epoch polarimetry, offering a rare opportunity to study structured circumstellar material (CSM). We aim to characterise the kinematics, composition and geometry of the CSM around SN 2024abvb and to identify plausible progenitor/ejection scenarios that can produce the observed spectro-polarimetric evolution. We present high-resolution (VLT/UVES and VLT/X-Shooter) optical/NIR spectroscopy across several epochs, complemented by broadband polarimetry and spectropolarimetry (VLT/FORS2 and NOT/ALFOSC). Line identifications, velocity decompositions and polarimetric time-series are used to trace multiple kinematic components and changes in scattering geometry. The high-resolution spectra reveal multiple narrow CSM components composed of He, C and O with absorption minima at $\sim 150-400$ km s${}^{-1}$ and additional faster material up to $\sim 2000$ \kms. Low-velocity Balmer absorptions are present, indicating distant H-rich material, a first in SNe Ibn/Icn. Polarimetry shows a marked evolution ($P\sim 1\%$ near peak, $\lesssim 0.5\%$ after $\sim 1$ week, rising to $\sim 1.5\%$ at $\sim 20$ d with $\sim 50^{\circ }$ position-angle rotation and to $\sim 4\%$ at $\sim 30$ d, stronger in the blue), implying a time-variable, wavelength-dependent scattering/obscuration component. The combination of kinematics and polarimetric behaviour is consistent with multiple, concentric toroidal shells with differing orientations and partial dust content.

Accepted on 07/04/2026 - 16 pages, 14 figures, 6 pages in appendix

References in corpus (82)

• Measuring Reddening with SDSS Stellar Spectra and Recalibrating SFD
• A Comprehensive Measurement of the Local Value of the Hubble Constant with 1 km/s/Mpc Uncertainty from the Hubble Space Telescope and the SH0ES Team
• The Zwicky Transient Facility: System Overview, Performance, and First Results
• Overview of the DESI Legacy Imaging Surveys
• ATLAS: A High-Cadence All-Sky Survey System
• X-shooter, the new wide band intermediate resolution spectrograph at the ESO Very Large Telescope
• Common Envelope Evolution: Where we stand and how we can move forward
• Mass Loss: Its Effect on the Evolution and Fate of High-Mass Stars
• Formation of Double Neutron Star Systems
• The Effects of Binary Evolution on the Dynamics of Core Collapse and Neutron-Star Kicks
• Tidal Disruption Events
• Type Iax Supernovae: A New Class of Stellar Explosion
• Design and operation of the ATLAS Transient Science Server
• A faint type of supernova from a white dwarf with a helium-rich companion
• An atmospheric radiation model for Cerro Paranal. I. The optical spectral range
• K-corrections and Extinction Corrections for Type Ia Supernovae
• A Circumbinary Disk in the Final Stages of Common Envelope and the Core-Degenerate Scenario for Type Ia Supernovae
• Stellar Streams Discovered in the Dark Energy Survey
• High Density Circumstellar Interaction in the Luminous Type IIn SN 2010jl: The first 1100 days
• The Most Luminous Supernovae
• The Fast, Luminous Ultraviolet Transient AT2018cow: Extreme Supernova, or Disruption of a Star by an Intermediate-Mass Black Hole?
• An investigation into the prominence of spiral galaxy bulges
• Broad emission lines from opaque electron-scattering environment of SN 1998S
• Massive stars exploding in a He-rich circumstellar medium. I. Type Ibn (SN 2006jc-like) events
• Interacting Supernovae: Types IIn and Ibn
• Have the Elusive Progenitors of Supernovae Type Ia Been Discovered?
• The Palomar Transient Factory Core-Collapse Supernova Host-Galaxy Sample. I. Host-Galaxy Distribution Functions and Environment-Dependence of CCSNe
• Massive stars exploding in a He-rich circumstellar medium III. SN 2006jc: IR echoes from new and old dust in the progenitor CSM
• A Neutron Star Binary Merger Model for GW170817/GRB170817a/SSS17a
• EC-SNe from super-AGB progenitors: theoretical models vs. observations
• A WC/WO star exploding within an expanding carbon-oxygen-neon nebula
• Detection of CO and Dust Emission in Near-Infrared Spectra of SN 1998S
• A mass-dependent slope of the galaxy size-mass relation out to z~3: further evidence for a direct relation between median galaxy size and median halo mass
• Inferring supernova IIb/Ib/Ic ejecta properties from light curves and spectra: Correlations from radiative-transfer models
• Massive stars exploding in a He-rich circumstellar medium. II. The transitional case of SN 2005la
• The physical properties of AM CVn stars: new insights from Gaia DR2
• The prevalence and influence of circumstellar material around hydrogen-rich supernova progenitors
• Observational properties of extreme supernovae
• The Type Icn SN 2021csp: Implications for the Origins of the Fastest Supernovae and the Fates of Wolf-Rayet Stars
• Massive stars exploding in a He-rich circumstellar medium. IV. Transitional Type Ibn Supernovae
• Electron-capture supernovae exploding within their progenitor wind
• Asymmetries in the Type IIn SN2010jl
• On the formation of neutron stars via accretion-induced collapse in binaries
• SN 2011hw: Helium-Rich Circumstellar Gas and the Luminous Blue Variable to Wolf-Rayet Transition in Supernova Progenitors
• Supersolar Ni/Fe production in the Type IIP SN 2012ec
• The Dual-Axis Circumstellar Environment of the Type IIn Supernova 1997eg
• PS1-12sk is a Peculiar Supernova From a He-rich Progenitor System in a Brightest Cluster Galaxy Environment
• Properties of Type Ibn Supernovae: Implications for the Progenitor Evolution and the Origin of a Population of Rapid Transients
• Nested Dust Shells around the Wolf-Rayet Binary WR 140 observed with JWST
• SN2010jp (PTF10aaxi): A Jet-Driven Type II Supernova
• Investigating the diversity of supernovae type Iax: A MUSE and NOT spectroscopic study of their environments
• The radial distribution of core-collapse supernovae in spiral host galaxies
• Supernova Impostors and other Gap Transients
• SN 2015U: A Rapidly Evolving and Luminous Type Ibn Supernova
• Characterization of Low Surface Brightness structures in annotated deep images
• The Diverse Properties of Type Icn Supernovae Point to Multiple Progenitor Channels
• Rapidly evolving faint transients from stripped-envelope electron-capture supernovae
• The Nearby Type Ibn Supernova 2015G: Signatures of Asymmetry and Progenitor Constraints
• The Progenitors of Calcium-Strong Transients
• A radio-detected Type Ia supernova with helium-rich circumstellar material
• A New View of the Size-Mass Distribution of Galaxies: Using $r_{20}$ and $r_{80}$ instead of $r_{50}$
• OGLE-2013-SN-079: a lonely supernova consistent with a helium shell detonation
• LISA and the Existence of a Fast-Merging Double Neutron Star Formation Channel
• Stable nickel production in Type Ia supernovae: A smoking gun for the progenitor mass?
• The BlackGEM telescope array I: Overview
• The lowest of the low: discovery of SN 2019gsc and the nature of faint Iax supernovae
• Nebular spectroscopy of SN 2014J: Detection of stable nickel in near infrared spectra
• Measuring an off-Center Detonation through Infrared Line Profiles: The peculiar Type Ia Supernova SN~2020qxp/ASASSN-20jq
• SN 2020kyg and the rates of faint Iax Supernovae from ATLAS
• Tips and Tricks in linear imaging polarimetry of extended sources with FORS2 at the VLT
• Mass-transferring binary stars as progenitors of interacting hydrogen-free supernovae
• Polarimetry of Hydrogen-Poor Superluminous Supernovae
• Post-dynamical inspiral phase of common envelope evolution: Binary orbit evolution and angular momentum transport
• Strategies for optimal sky subtraction in the low surface brightness regime
• SN 2021foa, a transitional event between a Type IIn (SN 2009ip-like) and a Type Ibn supernova
• A cosmic formation site of silicon and sulphur revealed by a new type of supernova explosion
• Extragalactic Stellar Tidal Streams in the Dark Energy Survey
• Photometry and spectroscopy of the Type Icn supernova 2021ckj: The diverse properties of the ejecta and circumstellar matter of Type Icn SNe
• SN 2016dsg: A Thermonuclear Explosion Involving A Thick Helium Shell
• JWST and Ground-based Observations of the Type Iax Supernovae SN 2024pxl and SN 2024vjm: Evidence for Weak Deflagration Explosions
• Probing gas and dust in the tidal tail of NGC 5221 with the type Ia supernova iPTF16abc
• Insights into the Properties of Type Ibn/Icn Supernovae and Their Progenitor Channels through X-ray Emission