Current date: 2026-09-29

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Datestamp limit: 2026-09-29 (0 days ago)

Created/updated limit: 2026-09-22 (7 days ago)

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OAI-PMH request: http://export.arxiv.org/oai2?verb=ListRecords&from=2026-09-29&until=2026-09-29&set=physics&metadataPrefix=arXiv

Scoring abstracts

Number of records retrieved: 113

Keyword score statistics

score 9 -- 1 abstracts

score 6 -- 1 abstracts

score 4 -- 1 abstracts

score 3 -- 2 abstracts

score 2 -- 3 abstracts

in total -- 8 abstracts

Articles that appeared on 2026-09-29

[abstract 1 / 8] Wow! (score: 9)
arXiv:2609.31836 [pdf, ps, other]

Title: Discovery of minute-scale POLARIZATION angle rotation in a supermassive BLACK HOLE JET

Authors: Aristeidis Polychronakis, Ioannis Liodakis, Dmitry Blinov, Anastasia Glykopoulou, Sebastian Kiehlmann, Karan Pal, Georgios F. Paraschos, Lena Debbrecht, Swati Ravi, Herman L. Marshall,

Comments: Accepted for publication in ApJL, 9 pages, 5 figures

Subjects: astro-ph.HE

Created: 2026-09-25; Updated: 2026-09-29; Datestamp: 2026-09-29

Relativistic JETs from supermassive BLACK HOLEs oriented towards our line of sight called BLAZARs have puzzled the astronomical community for decades. Their fast JETs and preferential alignment creates a fog of RELATIVISTIC effects that obscures their true properties. Optical polarimetry - tracing the uniformity, direction, and evolution of the MAGNETic field in the JETs, has revealed a unique phenomenon to BLAZARs; coherent changes of the MAGNETic field manifesting as rotations of the POLARIZATION angle ($Ψ$). The origin of those rotations has been debated for decades with several proposed models to explain them. We detected an extremely fast - minute time-scale - rotation in the POLARIZATION angle of $\sim136^\circ$ over the span of about 80 minutes, making it the fastest known rotation by almost an order of magnitude. Our optical POLARIZATION observations combined with radio very long baseline interferometry allow us to reject different models of particle acceleration and strongly point to RELATIVISTIC effects and the interaction of standing and moving shock waves as the origin of the extreme POLARIZATION variations in JETs.

[abstract 2 / 8] Yes (score: 6)
arXiv:2609.31826 [pdf, ps, other]

Title: MUSE spectroscopy of the compact dual AGN in the $z=3.273$ radio-loud gravitational lens MG B2016+112

Authors: Jianghao Huyan, Júlia M. Sisk-Reynés, Daniel A. Schwartz, Varsha P. Kulkarni, Anna Barnacka, Adi Foord, Charlotte A. Eades,

Comments: 12 pages, 4 figures, 2 tables. Submitted to ApJL. Comments are welcome!

Subjects: astro-ph.GA

Created: 2026-09-25; Updated: 2026-09-29; Datestamp: 2026-09-29

Dual ACTIVE GALACTIC NUCLEi (AGN) are unique laboratories for studying how galaxy mergers trigger accretion onto supermassive BLACK HOLEs (SMBHs). However, at redshifts $z>1$, only few dual AGN are confirmed at projected separations $\gtrsim$ 1 kpc for the two SMBHs. We present archival MUSE spectroscopy of the three resolved lensed images of the radio-loud system MG B2016+112. At z = 3.273 and at a projected separation of 175 pc, this the most compact confirmed dual AGN at z > 1. We detect Ly$α$, C IV, N V, He II, and C III] emission across images A$--$C after correcting for ISM absorption at $z \sim 0$. We find that the Ly $α$, C IV, N V lines are affected by saturated absorption at $z \sim 3.27$. The He II / C III] emission-line ratios are consistent between images A and B but differ significantly from image C. We fit the C IV emission regions of images A$--$C by allowing for up to two Gaussians and use broad component to place lower limits on their respective SMBH masses: $\gtrsim 2 \times {10}^{7} M_\odot$, $\gtrsim 2.3 \times {10}^{7} M_\odot$, and $\gtrsim 1.5 \times {10}^{7} M_\odot$. Correcting for their strong lensing magnifications suggests Eddington ratios of $\lesssim$ 0.47, 0.51, and 0.04, respectively. Together with previous VLBI and X-ray analyses, our results provide strong, independent spectroscopic evidence that MG B2016+112 hosts two AGN. Our findings motivate deep, spatially resolved near-IR spectroscopy to independently revisit our mass estimates and determine the physical conditions of the host galaxy, which has likely undergone a major merger.

[abstract 3 / 8] Yes (score: 4)
arXiv:2609.31842 [pdf, ps, other]

Title: Correlated Signatures of Plasma Lensing in Fast Radio Bursts

Authors: Paz Beniamini, Pawan Kumar,

Comments: Submitted. Comments welcome

Subjects: astro-ph.HE

Created: 2026-09-25; Updated: 2026-09-29; Datestamp: 2026-09-29

Plasma lensing has been proposed to explain narrow spectra, multiple burst copies, frequency drifts, interference fringes, and POLARIZATION changes in fast radio bursts (FRBs). Because many of these features are not unique to lensing, a convincing identification requires several correlated observables to be reproduced by one lens model. We derive such relations for a one-dimensional Gaussian plasma lens near a fold caustic. We distinguish the phase separation of the merging images from their observable group-delay difference and identify three regimes: resolved burst copies, overlapping images with negligible mutual coherence, and coherent spectral interference. We connect the magnification, image delay, spectral-envelope width, fringe spacing, differential dispersion, time-frequency caustic curvature, and the brightness and ordering of the third image. We derive separate finite-source constraints from large fold magnification and from fringe visibility, and relate the wave-optics magnification scale to the plasma column of the lens. High-contrast fringes simultaneously constrain the source size and the mutual coherence of the two image fields, which limits the intrinsic coherence of the FRB radiation once the observed spectrum and instrumental bandpass are accounted for. We also derive the conditions for differential Faraday rotation in MAGNETized lenses. Finally, we show that clean lensing by a volume-filling turbulent screen requires fine tuning between rare strong fluctuations and caustic confusion, suggesting that sparse sheets, filaments, interfaces, or shocked clumps are more promising lensing structures.

[abstract 4 / 8] (score: 3)
arXiv:2609.31835 [pdf, ps, other]

Title: $\textit{Nāpōwawā`enakaulua}$: a close QUASAR pair at cosmic dawn in the Aether survey

Authors: Silvia Onorato, Emanuele Paolo Farina, Roberto Decarli, Klaudia Protušová, Elia Pizzati, Debora Pelliccia, Devin S. Chu, Larry Lindsey Kimura, Leinani Lozi, Emily Peavy, Fabrizio Arrigoni-Battaia, Eduardo Bañados, Aaron J. Barth, Silvia Belladitta, Manuela Bischetti, Sarah E. I. Bosman, Hyunseop Choi, Tiago Costa, Anna-Christina Eilers, Xiaohui Fan, Simona Gallerani, Thomas R. Geballe, Anniek J. Gloudemans, Eunchong Kim, Brian C. Lemaux, Weizhe Liu, Yoshiki Matsuoka, Chiara Mazzucchelli, Atsuko Nitta, Jan-Torge Schindler, Andrew W. Stephens, Hyewon Suh, Fabian Walter, Feige Wang, Jinyi Yang,

Comments: 15 pages, 4 figures, 1 table. Under review for publication in ApJL

Subjects: astro-ph.GA astro-ph.CO

Created: 2026-09-25; Updated: 2026-09-29; Datestamp: 2026-09-29

We present the discovery and first characterization of $\textit{Nāpōwawā`enakaulua}$: the most compact known QUASAR pair candidate in the Epoch of Reionization, with a projected separation of only $0.98^{\prime\prime}$ ($\approx 5.56$ pkpc at $z \sim 6.08$) and a velocity offset of $Δv \simeq 15 \text{ km s}^{-1}$. Using spectroscopy from JWST/NIRSpec IFU, as part of the $\textit{Aether survey}$, Gemini/GNIRS and GMOS we characterize the continuum and emission line properties of the two QUASARs, enabling constraints on their BLACK HOLE masses ($M_{\text{BH}} \simeq 1.5 \times 10^9$ and $4.0 \times 10^8\,M_\odot$), accretion states ($λ_{\text{Edd}} \simeq 1.23$ and $1.07$), and systemic redshifts ($z_{\rm sys} \simeq 6.0781$ and $6.0785$). We place this pair in the cosmological context by comparing the chance of occurrence to extrapolations of high-$z$ QUASAR clustering measurements at larger scales, resulting in a $\sim 2-3$ order of magnitude excess with respect to expectations. This excess hints at an underlying population of merger-triggered QUASAR pairs at cosmic dawn or to a denser-than-average galactic environment. $\textit{Nāpōwawā`enakaulua}$ thus represents a crucial signpost to investigate the mass assembly of the first massive galaxies and BLACK HOLEs.

[abstract 5 / 8] (score: 3)
arXiv:2609.31886 [pdf, ps, other]

Title: Negative and Positive Cascade Rates of Slow Alfvénic Turbulence in Switchback and Non-switchback Intervals: \emph{Wind} Observations

Authors: Sofiane Bourouaine,

Comments: Accepted for publication in the Astrophysical Journal Letters (ApJL)

Subjects: astro-ph.SR astro-ph.EP physics.plasm-ph physics.space-ph

Created: 2026-09-25; Updated: 2026-09-29; Datestamp: 2026-09-29

We estimate the turbulent cascade rate in imbalanced Alfvénic turbulence in the slow solar wind using a Politano--Pouquet-based approach that does not require an isotropic assumption. We analyze selected 8-hour intervals provided by \emph{Wind} spacecraft. These intervals are characterized by near-homogeneity, weak velocity shear, and imbalanced Alfvénic fluctuations, and are classified as switchback or non-switchback depending on the angular spread of the MAGNETic field relative to the mean field. Switchback intervals are identified by large MAGNETic-field rotations, whereas non-switchback intervals exhibit only small angular deviations. Our results show that non-switchback intervals exhibit a positive total cascade rate and power spectra consistent with a $-3/2$ scaling, indicative of a forward energy cascade. In contrast, switchback intervals are characterized by a negative total cascade rate (inverse cascade), and by steeper power spectra with a spectral index of approximately $-1.6$. This indicates that large MAGNETic-field rotations can substantially modify the scale-to-scale energy transfer in Alfvénic slow solar wind. The results suggest that switchbacks may be associated with additional physical processes, such as local instabilities, or RECONNECTion-related structures, that alter the direction and magnitude of the turbulent cascade. These findings may help explain previous reports of negative cascade rates in imbalanced Alfvénic solar-wind turbulence.

[abstract 6 / 8] (score: 2)
arXiv:2609.31762 [pdf, ps, other]

Title: Radiative properties and optical appearance of a thin accretion disk around a charged-PFDM BLACK HOLE

Authors: Taiyang Zhang, Zongyuan Qin, Qian Feng, Zheng-Wen Long,

Comments:

Subjects: astro-ph.HE

Created: 2026-09-24; Updated: 2026-09-29; Datestamp: 2026-09-29

Accretion onto MAGNETically charged BLACK HOLEs in a perfect fluid DARK MATTER (PFDM) background opens a new window for testing strong-field gravity. This paper investigates the radiative properties and optical appearance of a thin accretion disk surrounding a charged-PFDM BLACK HOLE. We numerically compute the radiative energy flux, temperature distribution, and radiative efficiency, and employ a ray-tracing method to construct the direct images, secondary images, redshift distribution, and observed flux. By comparing with the Schwarzschild and pure PFDM cases, we find that the thin-disk efficiency of the charged-PFDM BLACK HOLE lies between the two, with the MAGNETic charge partially counteracting the dark-matter-induced efficiency enhancement; for M87*, the efficiency is estimated to be 7\%--8\%. The optical appearance is predominantly governed by the PFDM parameter, while the MAGNETic charge plays only a marginal role. Larger inclination angles give rise to stronger Doppler asymmetry, producing the characteristic ``hat-like'' shape. These results provide falsifiable predictions for future high-resolution observations, such as those by ngEHT, to distinguish dark-matter environments from MAGNETic-charge effects.

[abstract 7 / 8] (score: 2)
arXiv:2609.31879 [pdf, ps, other]

Title: Not all spins of black-hole binaries formed in clusters are isotropic and not all spins of black-hole binaries formed in isolation are aligned

Authors: Sofia Dossena, Davide Gerosa, Tristan Bruel,

Comments: 16 pages, 11 figures

Subjects: astro-ph.HE gr-qc

Created: 2026-09-25; Updated: 2026-09-29; Datestamp: 2026-09-29

Spin directions are promising observables for distinguishing between the formation channels of merging stellar-mass binary BLACK HOLEs with gravitational-wave observations. In this work, we challenge the standard expectation that binaries formed via dynamical interactions in stellar clusters have isotropically distributed spins and that binaries formed in isolation have spins aligned with the orbital angular momentum. For dynamically formed binaries, we account for observational findings suggesting that the spins of stars in clusters may exhibit a preferred degree of alignment and construct a simple geometrical description of the resulting black-hole spin directions. This results in an analytical joint distribution for the polar angles of first-generation black-hole binaries, whose key feature is a correlation between the two spin-orbit tilts. We show that, under reasonable assumptions and independently of the initial spin configuration, spins are fully randomized after a single black-hole merger, implying that binaries formed through hierarchical mergers have isotropically distributed spin orientations. For isolated binaries, we introduce a simple model for spin evolution as a function of the natal kick imparted during the first SUPERNOVA explosion, while accounting for tidal interactions and mass-ratio reversal. The resulting distribution is also fully analytic. We investigate the impact of RELATIVISTIC spin precession, as well as that of the finite escape speed of clusters, on our geometrically derived distributions. Our results provide a simple analytical framework for modeling the spin directions of merging BLACK HOLEs in gravitational-wave population fits.

[abstract 8 / 8] (score: 2)
arXiv:2609.31943 [pdf, ps, other]

Title: Transport of Magnetic Fields by Thermohaline Convection in Crystallizing White Dwarfs

Authors: Nicolas Frazao Fernandes, J. R. Fuentes, Jim Fuller,

Comments: 26 pages, 17 figures

Subjects: astro-ph.SR physics.flu-dyn physics.plasm-ph

Created: 2026-09-25; Updated: 2026-09-29; Datestamp: 2026-09-29

The origins of strong MAGNETic fields observed in many white dwarfs are uncertain. Recent observations show that such fields are more common for white dwarfs with crystallized cores. Crystallization creates a destabilizing composition gradient that drives thermohaline convection in the star's fluid envelope, which may play an important role in MAGNETic field emergence. We perform 3D MAGNETohydrodynamical simulations of thermohaline convection with MAGNETic fields of various strengths and orientations, using the Boussinesq approximation in periodic Cartesian boxes. Our simulations suggest that thermohaline convection can generate MAGNETic fields when the MAGNETic Prandtl number is large (i.e., low MAGNETic diffusivity), but they are likely too weak to account for those observed in MAGNETic white dwarfs. However, the simulations indicate that strong MAGNETic fields can be advected outwards by the thermohaline convection without being destroyed, depending on the net MAGNETic flux. Hence, crystallization-induced thermohaline mixing may transport MAGNETic fields initially trapped in white dwarf interiors to their outer layers, allowing them to be observed. However, additional simulations using more realistic geometry and MAGNETic field configurations will be needed to confirm this possibility.