---
DOAJ_listed: '1'
OA_place: publisher
OA_type: gold
_id: '21714'
abstract:
- lang: eng
  text: Be stars are rapidly rotating main-sequence stars that play a crucial role
    in understanding stellar evolution and binary interactions. In this Letter, we
    propose a new formation scenario for black hole (BH) + Be star binaries (hereafter
    BHBe binaries), where the Be star is produced through the wind Roche lobe overflow
    (WRLOF) mechanism. Our analysis is based on numerical simulations of the WRLOF
    process in massive binaries, building on recent theoretical work. We demonstrate
    that the WRLOF model can efficiently form BHBe binaries under reasonable assumptions
    on stellar wind velocities. Using rapid binary population synthesis, we estimate
    the population of such systems in the Milky Way, predicting ∼1800−3200 currently
    existing BHBe binaries originating from the WRLOF channel. These systems are characterized
    by high eccentricities and exceptionally wide orbits, with typical orbital periods
    exceeding 1000 days and a peak distribution around ∼10,000 days. Due to their
    long orbital separations, these BHBe binaries are promising targets for future
    detection via astrometric and interferometric observations.
acknowledgement: We are deeply grateful to the anonymous referee for the insightful
  comments, which have significantly improved the quality of this work. The authors
  express their gratitude to Zhaoyu Zuo and I. El Mellah for sharing the grids of
  wind accretion efficiencies. Z.L. thanks Matthias U. Kruckow for detailed discussions
  about the BH formation. This work is supported by the Natural Science Foundation
  of China (grant Nos. 12125303, 12525304, 12288102, 12090040/3, 12473034, 12503044,
  12333008, 12433009, 12422305, 12273105, 12073070, 12173081), the Strategic Priority
  Research Program of the Chinese Academy of Sciences (grant Nos. XDB1160303, XDB1160201,
  XDB1160000), the National Key R&D Program of China (grant Nos. 2021YFA1600403 and
  2021YFA1600400), the CAS “Light of West China,” the Yunnan Revitalization Talent
  Support Program-Science & Technology Champion Project (No. 202305AB350003) and Young
  Talent project, the International Centre of Supernovae (ICESUN), Yunnan Key Laboratory
  of Supernova Research (Nos. 202302AN360001 and 202201BC070003), Yunnan Fundamental
  Research Projects (No. 202401AT070139), and the Natural Science Foundation of Henan
  Province (No. 242300420944). X.C. acknowledges the New Cornerstone Science Foundation
  through the XPLORER PRIZE. The authors gratefully acknowledge the “PHOENIX Supercomputing
  Platform” jointly operated by the Binary Population Synthesis Group and the Stellar
  Astrophysics Group at Yunnan Observatories, Chinese Academy of Sciences.
article_number: L42
article_processing_charge: Yes
article_type: original
arxiv: 1
author:
- first_name: Zhenwei
  full_name: Li, Zhenwei
  last_name: Li
- first_name: Shi
  full_name: Jia, Shi
  last_name: Jia
- first_name: Dandan
  full_name: Wei, Dandan
  id: 5dd129bd-0601-11ef-b325-833284687b76
  last_name: Wei
- first_name: Hongwei
  full_name: Ge, Hongwei
  last_name: Ge
- first_name: Hailiang
  full_name: Chen, Hailiang
  last_name: Chen
- first_name: Yangyang
  full_name: Zhang, Yangyang
  last_name: Zhang
- first_name: Xuefei
  full_name: Chen, Xuefei
  last_name: Chen
- first_name: Zhanwen
  full_name: Han, Zhanwen
  last_name: Han
citation:
  ama: 'Li Z, Jia S, Wei D, et al. Formation of Be stars via wind accretion: Case
    study on Black Hole + Be star binaries. <i>The Astrophysical Journal Letters</i>.
    2026;996(2). doi:<a href="https://doi.org/10.3847/2041-8213/ae3008">10.3847/2041-8213/ae3008</a>'
  apa: 'Li, Z., Jia, S., Wei, D., Ge, H., Chen, H., Zhang, Y., … Han, Z. (2026). Formation
    of Be stars via wind accretion: Case study on Black Hole + Be star binaries. <i>The
    Astrophysical Journal Letters</i>. IOP Publishing. <a href="https://doi.org/10.3847/2041-8213/ae3008">https://doi.org/10.3847/2041-8213/ae3008</a>'
  chicago: 'Li, Zhenwei, Shi Jia, Dandan Wei, Hongwei Ge, Hailiang Chen, Yangyang
    Zhang, Xuefei Chen, and Zhanwen Han. “Formation of Be Stars via Wind Accretion:
    Case Study on Black Hole + Be Star Binaries.” <i>The Astrophysical Journal Letters</i>.
    IOP Publishing, 2026. <a href="https://doi.org/10.3847/2041-8213/ae3008">https://doi.org/10.3847/2041-8213/ae3008</a>.'
  ieee: 'Z. Li <i>et al.</i>, “Formation of Be stars via wind accretion: Case study
    on Black Hole + Be star binaries,” <i>The Astrophysical Journal Letters</i>, vol.
    996, no. 2. IOP Publishing, 2026.'
  ista: 'Li Z, Jia S, Wei D, Ge H, Chen H, Zhang Y, Chen X, Han Z. 2026. Formation
    of Be stars via wind accretion: Case study on Black Hole + Be star binaries. The
    Astrophysical Journal Letters. 996(2), L42.'
  mla: 'Li, Zhenwei, et al. “Formation of Be Stars via Wind Accretion: Case Study
    on Black Hole + Be Star Binaries.” <i>The Astrophysical Journal Letters</i>, vol.
    996, no. 2, L42, IOP Publishing, 2026, doi:<a href="https://doi.org/10.3847/2041-8213/ae3008">10.3847/2041-8213/ae3008</a>.'
  short: Z. Li, S. Jia, D. Wei, H. Ge, H. Chen, Y. Zhang, X. Chen, Z. Han, The Astrophysical
    Journal Letters 996 (2026).
date_created: 2026-04-12T22:01:50Z
date_published: 2026-01-10T00:00:00Z
date_updated: 2026-04-16T06:26:18Z
day: '10'
ddc:
- '520'
department:
- _id: YlGo
doi: 10.3847/2041-8213/ae3008
external_id:
  arxiv:
  - '2512.18565'
file:
- access_level: open_access
  checksum: 09200c1cf405101abdd298ce80c9a90d
  content_type: application/pdf
  creator: dernst
  date_created: 2026-04-16T06:24:30Z
  date_updated: 2026-04-16T06:24:30Z
  file_id: '21741'
  file_name: 2026_AstrophysicalJourLetters_Li.pdf
  file_size: 5202345
  relation: main_file
  success: 1
file_date_updated: 2026-04-16T06:24:30Z
has_accepted_license: '1'
intvolume: '       996'
issue: '2'
language:
- iso: eng
month: '01'
oa: 1
oa_version: Published Version
publication: The Astrophysical Journal Letters
publication_identifier:
  eissn:
  - 2041-8213
  issn:
  - 2041-8205
publication_status: published
publisher: IOP Publishing
quality_controlled: '1'
scopus_import: '1'
status: public
title: 'Formation of Be stars via wind accretion: Case study on Black Hole + Be star
  binaries'
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: 996
year: '2026'
...
---
DOAJ_listed: '1'
OA_place: publisher
OA_type: gold
PlanS_conform: '1'
_id: '21997'
abstract:
- lang: eng
  text: 'The massive binary common envelope (CE) phase plays a pivotal role in the
    formation of close black hole (BH)/neutron star binaries, yet significant uncertainties
    remain in our understanding of this process. In this study, we aim to constrain
    the massive binary CE phase by systematically reconstructing three observed BH
    X-ray binaries (BHXBs): GRO J1655-40, SAX J1819.3-2525, and 4U 1543-47. Through
    comprehensive binary evolution simulations and parametric supernova modeling,
    we establish lower limits for the CE efficiency parameters under different energy
    considerations within the standard energy formalism. Specifically, we derive minimum
    values for three cases: α0.5U and αU, representing CE efficiencies with half and
    all of the internal energy contributing to the envelope ejection, respectively,
    and αH, accounting for the envelope’s enthalpy. Our analysis reveals that the
    self-consistent formation of these three BHXBs requires CE efficiency parameters
    satisfying α0.5U ≳ 6.7, αU ≳ 4.2, and αH ≳ 1.7. Notably, we find no viable solutions
    with CE efficiency values below unity, even when considering the most extreme
    scenarios, in which the envelope binding energy is significantly reduced through
    enthalpy inclusion. Our results strongly imply that either additional energy sources
    are required or the formalism itself must be revised. Furthermore, we quantitatively
    assess the impact of BH natal kicks on our results. A key finding is that 4U 1543-47’s
    formation requires substantial natal kicks (≳50 km s−1), as lower kick velocities
    are incompatible with isolated binary evolution.'
acknowledgement: We deeply thank the referee for a very careful reading and constructive
  comments that have led to the improvement of the manuscript. The authors are grateful
  to Poshak Gandhi for his valuable suggestions and feedback on this work. This work
  is supported by the Natural Science Foundation of China (grant Nos. 12125303, 12525304,
  12288102, 12473034, 12103028, 12333008, 12422305, 12090040/3, 12273105, 11703081,
  11422324, 12073070, and 12173081), the CAS Project for Young Scientists in Basic
  Research (YSBR-148), the Strategic Priority Research Program of the Chinese Academy
  of Sciences (grant Nos. XDB1160303, XDB1160201, and XDB1160000), the National Key
  R&D Program of China (grant Nos. 2021YFA1600403 and 2021YFA1600400), the Key Research
  Program of Frontier Sciences of CAS (No. ZDBS-LY-7005), the “CAS Light of West China”,
  the Yunnan Revitalization Talent Support Program-Science & Technology Champion Project
  (No. 202305AB350003) and Young Talent Project, the International Centre of Supernovae
  (ICESUN), Yunnan Key Laboratory of Supernova Research (Nos. 202302AN360001 and 202201BC070003),
  Yunnan Fundamental Research Projects (No. 202401AT070139), and the Natural Science
  Foundation of Henan Province (No. 242300420944). X.C. acknowledges the New Cornerstone
  Science Foundation through the XPLORER PRIZE. The authors gratefully acknowledge
  the “PHOENIX Supercomputing Platform” jointly operated by the Binary Population
  Synthesis Group and the Stellar Astrophysics Group at Yunnan Observatories, Chinese
  Academy of Sciences.
article_number: '31'
article_processing_charge: Yes
article_type: original
arxiv: 1
author:
- first_name: Zhenwei
  full_name: Li, Zhenwei
  last_name: Li
- first_name: Dandan
  full_name: Wei, Dandan
  id: 5dd129bd-0601-11ef-b325-833284687b76
  last_name: Wei
- first_name: Shi
  full_name: Jia, Shi
  last_name: Jia
- first_name: Hailiang
  full_name: Chen, Hailiang
  last_name: Chen
- first_name: Hongwei
  full_name: Ge, Hongwei
  last_name: Ge
- first_name: Zhuo
  full_name: Chen, Zhuo
  last_name: Chen
- first_name: Yangyang
  full_name: Zhang, Yangyang
  last_name: Zhang
- first_name: Xuefei
  full_name: Chen, Xuefei
  last_name: Chen
- first_name: Zhanwen
  full_name: Han, Zhanwen
  last_name: Han
citation:
  ama: 'Li Z, Wei D, Jia S, et al. A path to constraints on common envelope ejection
    in massive binaries: Full evolutionary reconstruction of three Black Hole X-ray
    binaries. <i>The Astrophysical Journal</i>. 2026;1004(1). doi:<a href="https://doi.org/10.3847/1538-4357/ae66fd">10.3847/1538-4357/ae66fd</a>'
  apa: 'Li, Z., Wei, D., Jia, S., Chen, H., Ge, H., Chen, Z., … Han, Z. (2026). A
    path to constraints on common envelope ejection in massive binaries: Full evolutionary
    reconstruction of three Black Hole X-ray binaries. <i>The Astrophysical Journal</i>.
    IOP Publishing. <a href="https://doi.org/10.3847/1538-4357/ae66fd">https://doi.org/10.3847/1538-4357/ae66fd</a>'
  chicago: 'Li, Zhenwei, Dandan Wei, Shi Jia, Hailiang Chen, Hongwei Ge, Zhuo Chen,
    Yangyang Zhang, Xuefei Chen, and Zhanwen Han. “A Path to Constraints on Common
    Envelope Ejection in Massive Binaries: Full Evolutionary Reconstruction of Three
    Black Hole X-Ray Binaries.” <i>The Astrophysical Journal</i>. IOP Publishing,
    2026. <a href="https://doi.org/10.3847/1538-4357/ae66fd">https://doi.org/10.3847/1538-4357/ae66fd</a>.'
  ieee: 'Z. Li <i>et al.</i>, “A path to constraints on common envelope ejection in
    massive binaries: Full evolutionary reconstruction of three Black Hole X-ray binaries,”
    <i>The Astrophysical Journal</i>, vol. 1004, no. 1. IOP Publishing, 2026.'
  ista: 'Li Z, Wei D, Jia S, Chen H, Ge H, Chen Z, Zhang Y, Chen X, Han Z. 2026. A
    path to constraints on common envelope ejection in massive binaries: Full evolutionary
    reconstruction of three Black Hole X-ray binaries. The Astrophysical Journal.
    1004(1), 31.'
  mla: 'Li, Zhenwei, et al. “A Path to Constraints on Common Envelope Ejection in
    Massive Binaries: Full Evolutionary Reconstruction of Three Black Hole X-Ray Binaries.”
    <i>The Astrophysical Journal</i>, vol. 1004, no. 1, 31, IOP Publishing, 2026,
    doi:<a href="https://doi.org/10.3847/1538-4357/ae66fd">10.3847/1538-4357/ae66fd</a>.'
  short: Z. Li, D. Wei, S. Jia, H. Chen, H. Ge, Z. Chen, Y. Zhang, X. Chen, Z. Han,
    The Astrophysical Journal 1004 (2026).
date_created: 2026-06-14T22:01:42Z
date_published: 2026-06-10T00:00:00Z
date_updated: 2026-06-19T09:58:52Z
day: '10'
ddc:
- '520'
department:
- _id: YlGo
doi: 10.3847/1538-4357/ae66fd
external_id:
  arxiv:
  - '2604.10440'
file:
- access_level: open_access
  checksum: bb76fbb51f8d2834cb79f19e7932e3bd
  content_type: application/pdf
  creator: dernst
  date_created: 2026-06-19T09:56:29Z
  date_updated: 2026-06-19T09:56:29Z
  file_id: '22099'
  file_name: 2026_AstrophysicalJour_Li.pdf
  file_size: 3386217
  relation: main_file
  success: 1
file_date_updated: 2026-06-19T09:56:29Z
has_accepted_license: '1'
intvolume: '      1004'
issue: '1'
language:
- iso: eng
month: '06'
oa: 1
oa_version: Published Version
publication: The Astrophysical Journal
publication_identifier:
  eissn:
  - 1538-4357
  issn:
  - 0004-637X
publication_status: published
publisher: IOP Publishing
quality_controlled: '1'
scopus_import: '1'
status: public
title: 'A path to constraints on common envelope ejection in massive binaries: Full
  evolutionary reconstruction of three Black Hole X-ray binaries'
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: 1004
year: '2026'
...