Multiepoch Detection of an Ultrafast Inflow in ESP 39607: Evidence for an Accretion Cascade
14 affiliations
- 1Eureka Scientific
- 2Yale University
- 3Universidad Diego Portales
- 4Space Science Institute
- 5INAF—Osservatorio Astronomico di Roma
- 6Yale Center for Astronomy & Astrophysics
- 7University of Geneva
- 8James Madison University
- 9University of Modena and Reggio Emilia
- 10California Institute of Technology
- 11INAF—Osservatorio di Astrofisica e Scienza dello Spazio di Bologna
- 12Max-Planck-Institut für Extraterrestrische Physik
- 13University of Maryland
- 14INAF—Istituto di Astrofisica e Planetologia Spaziali
Abstract
We present simultaneous XRISM, XMM-Newton, and NuSTAR observations of ESP 39607, a Seyfert 2 galaxy at z = 0.201. XRISM/Resolve reveals two absorption features near 4.7 and 4.9 keV in the observed frame, consistent with redshifted Fe xxv He α and Fe xxvi Ly α absorption from gas inflowing at v in ≃ 0.16 c . The high velocity identifies the absorber as an ultrafast inflow (UFI), which is detected at ∼3 σ –3.7 σ across different methods and continuum models. Photoionization modeling yields log ξ / erg s − 1 cm ≃ 3.7 –3.8 and a column density log N H , abs / cm − 2 ≃ 23.2 –23.8, the latter depending on the assumed metallicity. The inflow velocity and line properties are consistent with those reported from two earlier NuSTAR epochs, indicating that similar inflowing material was present over a baseline of at least 2.2 yr in the source rest frame. Across all three epochs, the combined detection significance of the UFI is 5.3 σ . Given the dynamical timescale of a few days at the inferred radius, R ≃ 49–77 R g , the multiyear evidence favors a scenario in which the inflow is continuously replenished, forming an accretion “cascade,” rather than a single long-lived cloud. With an estimated mass inflow rate of M ̇ in ≃ 0.3 –1.4 M ⊙ yr ⁻¹ , depending on metallicity, and a ratio M ̇ in / M ̇ acc ≃ 0.2 –1.0, the inflow could supply a substantial fraction of the accretion needed to power the central active galactic nucleus.
Related
- Episodic Accretion Drives an Ultrafast Outflow and CH ₃ CN Shock Chemistry in G24.33+0.14
- Effects of Alfvénicity on the compressible energy cascade in magnetohydrodynamic solar-wind turbulence: Evidence from Parker Solar Probe, Solar Orbiter, and WIND observations
- Evidence for an accretion-driven subpopulation of black holes in GWTC-5.0
- Planetary Accretion Is Less Frequent in Wide Binaries: Evidence from Metal-Enriched White Dwarfs in DESI DR1
- Planetary Accretion Is Less Frequent in Wide Binaries: Evidence from Metal-enriched White Dwarfs in DESI DR1
BibTeX
@article{peca2026multiepoch,
title = {{Multiepoch Detection of an Ultrafast Inflow in ESP 39607: Evidence for an Accretion Cascade}},
author = {Alessandro Peca and Michael J. Koss and Roberto Serafinelli and C. Megan Urry and Claudio Ricci and Keigo Fukumura and Massimo Gaspari and Elias Kammoun and Alessia Tortosa and Giulia Cerini and Peter G. Boorman and Richard Mushotzky and Quirino D’Amato},
journal = {The Astrophysical Journal},
year = {2026},
month = oct,
doi = {10.3847/1538-4357/aea573},
url = {https://iopscience.iop.org/article/10.3847/1538-4357/aea573},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - Multiepoch Detection of an Ultrafast Inflow in ESP 39607: Evidence for an Accretion Cascade
AU - Alessandro Peca
AU - Michael J. Koss
AU - Roberto Serafinelli
AU - C. Megan Urry
AU - Claudio Ricci
AU - Keigo Fukumura
AU - Massimo Gaspari
AU - Elias Kammoun
AU - Alessia Tortosa
AU - Giulia Cerini
AU - Peter G. Boorman
AU - Richard Mushotzky
AU - Quirino D’Amato
PY - 2026
DA - 2026/10/21
JO - The Astrophysical Journal
DO - 10.3847/1538-4357/aea573
UR - https://iopscience.iop.org/article/10.3847/1538-4357/aea573
AB - We present simultaneous XRISM, XMM-Newton, and NuSTAR observations of ESP 39607, a Seyfert 2 galaxy at z = 0.201. XRISM/Resolve reveals two absorption features near 4.7 and 4.9 keV in the observed frame, consistent with redshifted Fe xxv He α and Fe xxvi Ly α absorption from gas inflowing at v in ≃ 0.16 c . The high velocity identifies the absorber as an ultrafast inflow (UFI), which is detected at ∼3 σ –3.7 σ across different methods and continuum models. Photoionization modeling yields log ξ / erg s − 1 cm ≃ 3.7 –3.8 and a column density log N H , abs / cm − 2 ≃ 23.2 –23.8, the latter depending on the assumed metallicity. The inflow velocity and line properties are consistent with those reported from two earlier NuSTAR epochs, indicating that similar inflowing material was present over a baseline of at least 2.2 yr in the source rest frame. Across all three epochs, the combined detection significance of the UFI is 5.3 σ . Given the dynamical timescale of a few days at the inferred radius, R ≃ 49–77 R g , the multiyear evidence favors a scenario in which the inflow is continuously replenished, forming an accretion “cascade,” rather than a single long-lived cloud. With an estimated mass inflow rate of M ̇ in ≃ 0.3 –1.4 M ⊙ yr ⁻¹ , depending on metallicity, and a ratio M ̇ in / M ̇ acc ≃ 0.2 –1.0, the inflow could supply a substantial fraction of the accretion needed to power the central active galactic nucleus.
SN - 0004-637X
SN - 1538-4357
ER -