Peer Revenue Impact factor: volatile

Papers

Fresh from arXiv, typeset properly. Highlighted words trade on the market.

Physics

Watch Physics

Monday 6 July

Instrumentation and Detectors

Detection of scintillation light in noble gases with wavelength-shifting optical fibers

S.R. Soleti, S. Torelli, G. Martínez-Lema et al. (+110 more)

Wavelength-shifting (WLS) techniques enable particle detectors based on noble gases, whose scintillation light is predominantly emitted in the vacuum-ultraviolet. We investigate WLS fibers coated with tetraphenyl butadiene (TPB) for scintillation light detection in gaseous xenon and argon at pressures up to 8.5 bar, motivated by future high-pressure xenon time-projection chambers of the NEXT program. Two detector configurations are studied: an elongated high-pressure vessel with four PTFE panels equipped with WLS fibers read by temperature-stabilized SiPMs, and a compact box-shaped detector operated at 1 bar Xe with WLS fibers read out by PMTs. Both operate with continuous gas purification. The detector response is characterized using cosmic muons and alpha particles from a $^{241}$Am source. With the SiPM setup, we measure a light collection efficiency (LCE) of ${1.18 \pm 0.01~\mathrm{(sta.)}~^{+0.07}_{-0.09}~\mathrm{(sys.)}~\%}$ for xenon and ${1.07 \pm 0.01~\mathrm{(sta.)}~^{+0.06}_{-0.08}~\mathrm{(sys.)}~\%}$ for argon. With PMT readout, we measure a LCE of ${0.45 \pm 0.01~\mathrm{(sta.)} \pm 0.05~\mathrm{(sys.)}~\%}$ in xenon, in agreement with the SiPM result once photon detection efficiency is accounted for. Average scintillation waveforms in xenon and argon are studied to assess the time structure of the emitted light. Cosmic-muon measurements yield a mean energy required to produce a scintillation photon $45\pm7~\mathrm{(sta.)}~^{+4}_{-5}~\mathrm{(sys.)}~\mathrm{eV}$ at 1.5 bar, in agreement with the literature. The results demonstrate that TPB-coated WLS fiber systems can reliably detect scintillation light in high-pressure gaseous noble detectors, with a LCE representing an upper limit for realistic large-scale TPCs, where additional photon losses from materials and fiber attenuation are expected.
Read the full abstract

All authors S.R. Soleti, S. Torelli, G. Martínez-Lema, H. Almazán, A. Beck, A. Castillo, M. del Barrio-Torregrosa, P. Dietz, C. Echeverria, L. Gurriana, Y. Ifergan, I. Israelashvili, F. Lopez, F. Monrabal, E. Oblak, J. Pelegrin, J.G.M. Saraiva, M. Seemann, L. Arazi, J.J. Gómez-Cadenas, V. Álvarez, I.J. Arnquist, F. Auria-Luna, S. Ayet, Y. Ayyad, C.D.R. Azevedo, F. Ballester, J.E. Barcelon, J.M. Benlloch-Rodríguez, F.I.G.M. Borges, A. Brodoline, E. Church, M. Cid, X. Cid, C.A.N. Conde, C. Cortes-Parra, F.P. Cossío, R. Coupe, E. Dey, M. Elorza, R. Esteve, R. Felkai, L.M.P. Fernandes, P. Ferrario, F.W. Foss, Z. Freixa, J. García-Barrena, J.W.R. Grocott, R. Guenette, J. Hauptman, C.A.O. Henriques, J.A. Hernando Morata, P. Herrero-Gómez, V. Herrero, C. Hervés Carrete, A.F.B. Isabel, B.J.P. Jones, F. Kellerer, L. Larizgoitia, A. Larumbe, P. Lebrun, N. López-March, R. Madigan, R.D.P. Mano, A. Marauri, A.P. Marques, J. Martín-Albo, A. Martínez, M. Martínez-Vara, R.L. Miller, K. Mistry, J. Molina-Canteras, C.M.B. Monteiro, F.J. Mora, K.E. Navarro, P. Novella, D.R. Nygren, I. Osborne, J. Palacio, B. Palmeiro, A. Para, A. Pazos, M. Pérez Maneiro, M. Querol, J. Renner, I. Rivilla, C. Rogero, L. Rogers, B. Romeo, C. Romo-Luque, E. Ruiz-Chóliz, P. Saharia, F.P. Santos, J.M.F. dos Santos, I. Shomroni, A.L.M. Silva, P.A.O.C. Silva, A. Simón, M. Sorel, J. Soto-Oton, J.M.R. Teixeira, S. Teruel-Pardo, J.F. Toledo, C. Tonnelé, J. Torrent, A. Trettin, P.R.G. Valle, M. Vanga, P. Vázquez Cabaleiro, J.F.C.A. Veloso, J.D. Villamil, J. Waiton, A. Yubero-Navarro

Astrophysics of Galaxies

MICONIC: The spatial relationship between star formation and the AGN in Centaurus A revealed by JWST/MIRI

O. C. Jones, M. L. Jones, D. Dicken et al. (+21 more)

Centaurus A (Cen A), the nearest active radio galaxy, hosts a warped dust disc formed in a gas-rich merger. We present JWST/MIRI imaging in three filters, F560W, F770W, and F1130W, of this central disc over a ~4 x 2 kpc region to characterise its resolved mid-infrared stellar populations. The images reveal a system of extended dusty structures, previously identified with Spitzer as an "oval dusty shell", now resolved into multiple loop-like features that are brightest in F1130W and closely associated with the warped disc. Colour-magnitude and colour-colour diagnostics reveal a distinct population of 928 red point sources with strong infrared excess, accounting for ~36 per cent of sources with high-quality photometry in all three bands, spatially confined to the disc. These sources exhibit rising mid-infrared spectral slopes indicative of emission from warm dust. Their colours and spatial distribution are consistent with a population dominated by embedded young stellar objects, tracing recent (~10^5-10^6 yr) star formation within the disc. The strong geometric alignment of these sources with the disc, together with the lack of correlation with the radio jet, suggests that star formation in the central regions of Cen A is primarily regulated by merger-accreted gas, with no strong evidence for AGN jet-ISM interactions.
Read the full abstract

All authors O. C. Jones, M. L. Jones, D. Dicken, G. S. Wright, M. García Marín, A. Alonso Herrero, P. Guillard, K. Justtanont, M. Meixner, A. Labiano, D. Rouan, P. van der Werf, L. Pantoni, V. A. Buiten, T. Böker, G. Östlin, L. Evangelista, M. Baes, L. Colina, L. Hermosa Muñoz, Th. Henning, M. Güdel, T. P. Ray, P.-O. Lagage

Physics and Society · Cross-listed from q-bio.QM

Parenclitic hypergraphs and their application in personalized cancer therapy

K. K. H. Manjunatha, D. Aleja, F. Liu et al. (+16 more)

Understanding the differences between individual instances of the same complex system remains a central challenge, particularly in biological contexts. Parenclitic networks constitute a suitable means to detect deviations in correlations with respect to reference populations. Here, we introduce parenclitic hypergraphs, a general framework for identifying anomalies in higher-order correlations across arbitrary interaction orders. After validating the method on synthetic datasets and benchmark ones, we apply it to patient-derived cancer organoids, capturing temporal changes in gene expression between healthy and cancerous tissues as the disease progresses. Our approach not only reproduces known oncogenic signatures, but also reveals a previously unrecognized candidate therapeutic target. Since organoids are generated from individual patients, our method provides, for the first time, a viable protocol for personalized cancer therapy based on higher-order correlation patterns. These findings offer a novel, systems-level strategy for precision oncology grounded in complex systems theory.
Read the full abstract

All authors K. K. H. Manjunatha, D. Aleja, F. Liu, M. Zhang, Y. Qi, L. Minati, G.-Q. Sun, S. Zhuang, C. Cai, J. Li, R. Criado, M. Romance del Rio, D. Papo, Y.-J. Ma, F. Fang, C. I. del Genio, Z. Zhao, H. Gao, S. Boccaletti

Quantum Physics

Noise-limited secret key agreement with twin optical physically unclonable functions

Georgios M. Nikolopoulos

We investigate the use of twin optical fingerprints derived from correlated physical unclonable functions (PUFs), as a hardware-based platform for cryptographic key generation and distribution. Each fingerprint is associated with a random, yet reproducible speckle pattern, generated when coherent light is scattered by a disordered optical structure. We consider a pair of correlated optical PUFs, and study the conditions under which two honest parties can establish a common secret key, despite fabrication-induced variability and environmental noise. An explicit information-theoretic key-agreement protocol is developed, incorporating secure sketches, error reconciliation, and privacy amplification. We quantify information leakage due to public helper data, and derive lower bounds on the length of the final secret key. The analysis identifies the noise regimes in which secure key agreement is feasible, and examines the performance of both practical and near-capacity reconciliation schemes. Finally, we discuss how twin optical PUFs could be integrated into quantum key distribution (QKD) networks, as a mechanism for establishing an initial pre-shared secret key between two honest users, without relying on computational assumptions or trusted third parties.
Read the full abstract

High Energy Physics (Phenomenology)

Beyond Half-Life Limits: Robust Operator-Level Interpretation of Multi-Isotope Neutrinoless Double-Beta Decay

K. Ishidoshiro

Current and future neutrinoless double-beta decay ($0\nu\beta\beta$) searches are usually characterized by half-life limits or projected sensitivities. For operator-level interpretation, however, the relevant question is not only the strength of the limit, but also the stability of the inferred constraints on low-energy lepton-number-violating (LNV) coefficients under changes of isotope and nuclear matrix-element (NME) method. Using $\nu$DoBe, we convert half-life limits or projected sensitivities into limits on low-energy LNV coefficients for several choices of isotope, operator class, and NME method. We then compare the resulting limits across isotopes and NME methods. We quantify the stability by the spread of coefficient limits in non-observation scenarios and, for single-operator post-discovery benchmarks, by the spread of isotope-to-isotope half-life ratios. For the operator examples considered in this paper, the light-Majorana exchange mechanism gives the most stable interpretation. The selected dimension-six operators remain reasonably robust, while the short-range dimension-nine examples show a stronger dependence on isotope and NME-method choices. The same hierarchy appears in post-discovery benchmarks based on isotope-to-isotope half-life ratios: the reliability of such tests depends on whether the predicted half-life pattern remains stable across NME methods. A multi-isotope $0\nu\beta\beta$ program therefore provides information beyond half-life reach by testing the stability of the operator interpretation. This spread-based analysis provides a practical way to identify which low-energy operator scenarios are suitable for isotope-ratio tests after a possible discovery, and which require more care before being connected to ultraviolet models of lepton-number violation.
Read the full abstract

High Energy Physics (Theory)

Revisiting the Wess-Zumino-Witten Term in Nuclear and Quark Matter under Magnetic Fields and Rotation

Markus A. G. Amano, Minoru Eto, Muneto Nitta et al. (+1 more)

We study anomalous Wess-Zumino-Witten terms associated with the chiral anomaly in dense QCD matter under magnetic fields and rotation. By introducing electromagnetic, baryon number, and isospin background gauge fields, we write down the topological couplings of neutral mesons for the $N_f=2$ and $N_f=3$ cases. The resulting terms contain characteristic contributions proportional to $\vec{B} \cdot \vec{\nabla} \phi$ and $\vec{\Omega} \cdot \vec{\nabla} \phi$, where $\phi$ denotes $\pi^0$, $\eta$, or $\eta'$. These results are relevant to chiral soliton lattices in dense rotating matter.
Read the full abstract

All authors Markus A. G. Amano, Minoru Eto, Muneto Nitta, Shin Sasaki

Superconductivity

$H-T$ Phase diagram of CeRh$_{2}$As$_{2}$: Refinement of the parity-switch scenario

Changhee Lee and P. M. R. Brydon

The superconductivity of CeRh$_2$As$_2$ has drawn attention due to its first-order transition in magnetic fields. At first glance, the multiple superconducting (SC) phases as well as the first-order transition appear consistent with the parity-switch scenario, which emphasizes the role of strong Rashba spin-orbit coupling enabled by the locally non-centrosymmetric crystal structure. However, experimental phase diagrams exhibit notable deviations from this simple picture: thermodynamic measurements reveal a nearly vertical phase boundary of the high-field SC phase despite the orbital depairing effect, while transport measurements show that the initial slope of the high-field SC phase is steeper than that of the low-field SC phase. Here, we show that these discrepancies can be understood by considering the combined effects of nonsymmorphic band structure and coexisting antiferromagnetic order. We demonstrate that the symmetry-enforced electronic structure around the Dirac node and type-II Van Hove saddle points near the X point in the Brillouin zone boundary becomes more anisotropic with increased interlayer hopping amplitude, and this anisotropic band structure naturally accounts for the anomalous initial slope of the odd-parity SC phase. Meanwhile, a phenomenological theory incorporating coexisting antiferromagnetism explains the nearly vertical thermodynamic phase boundary as a consequence of field-enhanced odd-parity superconductivity enabled by the over-suppression of Pauli depairing.
Read the full abstract

Cosmology and Nongalactic Astrophysics

Inverse-k Primordial Oscillations from a Symbolic Regression Search

Ze-Yu Peng, Qing-Yu Lan and Yun-Song Piao

Oscillatory features in the primordial power spectrum, potential signatures of new physics in the early universe, are usually searched for using fixed templates. In this work, we perform a template-free search for primordial features using symbolic regression. We find that both Planck and the combined Planck+ACT+SPT-3G datasets independently select an inverse-$k$ oscillation, $\cos(B/k)$ with $B\simeq4\,\mathrm{Mpc}^{-1}$, as the leading low-complexity feature. Comparing this inverse-$k$ template with standard linear and logarithmic oscillating templates, we find that it fits the data best, showing a weak preference for a non-zero amplitude. Our results show that symbolic regression as a powerful machine learning technique can provide an interpretable, model-independent approach to cosmological discovery.
Read the full abstract

Optics

Focusing and light collection effects on plasma-induced frequency-resolved optical switching (PI-FROSt) traces

M. Guerras, Í. J. Sola, B. Alonso et al. (+4 more)

Plasma-Induced Frequency-Resolved Optical Switching (PI-FROSt) is a promising and recently proposed phase-matching-free technique for characterising ultrafast pulses across broad spectral ranges. We investigate the mechanisms of PI-FROSt trace formation through numerical simulations and experimental validation. The results reveal that trace characteristics are highly sensitive to the relative focusing geometry between pump and probe pulses, as well as the spatial region selected for signal collection. Depending on these conditions, the interplay between plasma defocusing and positive lens-like nonlinear effects causes either intensity depletion or enhancement in the probe beam, flipping the PI-FROSt trace. Simulations demonstrate that optimal gate stability also depends strongly on the focusing scheme and the collecting region. This study highlights that precise spatial and temporal optimisation is essential to properly exploit the benefits of this broadband pulse characterisation technique.
Read the full abstract

All authors M. Guerras, Í. J. Sola, B. Alonso, E. Conejero Jarque, I. Lopez-Quintas, J. San Roman, A. Crego

Instrumentation and Methods for Astrophysics

HRMOS: A High-Resolution Multi-Object Spectrograph for the VLT

Laura Magrini, Thomas Bensby, Sofia Randich et al. (+174 more)

This White Paper presents the scientific rationale and instrument concept for HRMOS (High-Resolution Multi-Object Spectrograph), a next-generation instrument proposed for the ESO Very Large Telescope within the VLT 2030 roadmap. Current and planned facilities offer either multi-object spectroscopy or ultra-high spectral resolution, but not both. HRMOS fills this gap by combining very high spectral resolution, multi-object capability, and radial-velocity stability, enabling transformative studies in Galactic and extragalactic astrophysics. The baseline design provides a resolving power of R = 80000, radial-velocity precision of 10 m s-1 (goal: 5 m s-1), simultaneous observations of 50-60 targets, and broad optical coverage down to 385 nm. These capabilities enable precise measurements of elemental abundances, isotopic ratios, line profiles, and radial velocities for large stellar samples, including crowded fields, star clusters, the Galactic bulge, and nearby dwarf galaxies. HRMOS will address key questions on the age of the oldest stellar populations through nucleocosmochronology, the formation and survival of planetary systems, the assembly history of the Milky Way and satellites, the origin of the heaviest elements, stellar evolution, and the chemical and dynamical properties of the interstellar and circumgalactic medium. It will bridge large spectroscopic surveys and the next generation of extremely large telescopes, with strong synergies with 4MOST, Gaia, TESS, PLATO, the proposed Haydn mission, and future ELT instruments. Building on VLT/FLAMES heritage, HRMOS represents a strategic investment for European astronomy in the 2030s.
Read the full abstract

All authors Laura Magrini, Thomas Bensby, Sofia Randich, Andrea Bianco, Oscar Gonzalez, Emma Fernandez-Alvar, Sergio G. Sousa, Letizia Caito, Marco Riva, Vardan Adibekyan, Anish M. Amarsi, Maria Teresa Belmonte, Maria Benito, Christian P. Clear, Camilla Danielski, Valentina D'Orazi, Riano Giribaldi, Camilla J. Hansen, Vanessa Hill, Robin D. Jeffries, Georges Kordopatis, Andrea Miglio, Dinko Milakovic, Germano Sacco, Jose Schiappacasse-Ulloa, Asa Skuladottir, Rodolfo Smiljanic, Maria Tsantaki, Almudena Arcones, Jose Maria Arroyo-Polonio, Martina Baratella, Beatriz Barbuy, John R. Barnes, Giuseppina Battaglia, Holger Baumgardt, Katia Biazzo, Manuela Bischetti, Angela Bragaglia, Tobias Buck, Sven Buder, Sema Caliskan, Gabriele Cescutti, Andrew Collier Cameron, Ryan Cooke, Sergio Cristallo, Francesco Damiani, Arnas Drazdauskas, Heitor Ernandes, Antonio Frasca, Mark Gieles, Valeria Grisoni, Moira Jardine, Evan N. Kirby, Jonas Klevas, Andreas Korn, Ioanna Koutsouridou, Cis Lagae, Nadege Lagarde, Romain Lucchesi, Francesca Lucertini, Luca Malavolta, Fabiola Marino, Tadafumi Matsuno, Thibault Merle, Sapna Mishra, Marta Molero, Mario Montalto, Michele Moresco, Alessio Mucciarelli, Domenico Nardiello, Valerio Nascimbeni, Brunella Nisini, Joana Oliveira, Elenia Pacetti, Marco Palla, Marco Pignatari, Danae Polychroni, Federico Rizzuti, Donatella Romano, Stefania Salvadori, Luca Sbordone, Emanuele Spitoni, Matthew R. Standing, Grazina Tautvaivsiene, Yuan-Sen Ting, Andrea Travascio, Diego Turrini, Sophie Van Eck, Kim Venn, Diego Vescovi, C. Clare Worley, Nick Wright, Robert Yates, Alice Zocchi, Laura Affer, Carlos Allende, Paul Barklem, Michele Bellazzini, Serena Benatti, Leda Berni, Francesco Borsa, Maurizio Busso, Tiago Campante, Roberta Carini, Brad Carter, Giada Casali, Mario Damasso, Elisa Delgado Mena, Ignacio Del Moral Castro, Silvano Desidera, Maria Pia Di Mauro, Ana Escorza, Sergio Fonte, Elena Franciosini, Xiaoting Fu, Paolo Giacobbe, Terese Thidemann Hansen, Henrik Hartman, Keith Hawkins, Neda Heidari, Krzysztof Helminiak, H. Jens Hoeijmakers, Stavro Lambrov Ivanovski, Pascale Jablonka, Chiaki Kobayashi, Arunas Kucinskas, Carmela Lardo, Sebastiano Ledda, Alesandra Lehtmets, Karin Lind, João J.G. Lima, Sara Lucatello, Fatemeh Zahra Majidi, Sarah Martell, Anna McLeod, Sergio Molinari, Stephanie Monty, Benjamin Montet, Michael T. Murphy, Henryka Netzel-Iłkiewicz, Belinda Nicholson, Patrick Palmeri, Luca Pasquini, Lorenzo Pino, Romolo Politi, Francesca Primas, Pascal Quinet, Monica Rainer, Heleri Ramler, Yassin Rany Khalil, Martina Rossi, Eugenio Schisano, Federico Sestito, Paolo Simonetti, Arianna Vasini, Silvia Vicente, Carlos Viscasillas Vazquez, Manuela Zocchi, Michele Zusi, Andrea Baruffolo, Martin Black, Anna Brucalassi, Simone D'Auria, Vincenzo De Caprio, Michele Frangiamore, Enrico Giro, Robert J. Harris, Alen Khanbekyan, Enrique Joven, Tom Louth, Matteo Munari, Graham J. Murray, Luis Fernando Rodriguez Ramos, Bernardo Salasnich, William Taylor, Andrea Tozzi, Steven Watson

Quantum Physics

How Hard Is Quantum Advantage? A Cloud Microphysics Stress Test for Variational Quantum Models

Felix Herbort, Ellen Sarauer, Daniel Ohl de Mello et al. (+7 more)

Quantum machine learning (QML) could have the potential to leverage advantages of quantum over classical computing but still lacks strong evidence of actual improvements and scalability, partly due to phenomena such as barren plateaus. In this paper, we employ a hybrid quantum neural network (QNN) on a dataset on cloud microphysics, containing processes for phase transitions of water in the atmosphere and its related temperature changes, which are highly relevant for accurate climate predictions and projections. To reach optimal performance of our QNNs, we employ a rich and trainable frequency spectrum together with expressivity enhancing classical postprocessing. We find that our QNNs strongly benefit from extensive hyperparameter optimization and thereby demonstrate the feasibility of applying QNNs to complex physical systems. At the same time, the QNNs are outperformed by classical baselines in the form of simple fully-connected neural networks. We discuss identified bottlenecks of this class of quantum models to learn the full complexity of the cloud microphysics dataset to show that there is a need to further understand and improve variational quantum models for machine learning such that they might fill the gap where classical models fail or are inefficient.
Read the full abstract

All authors Felix Herbort, Ellen Sarauer, Daniel Ohl de Mello, Paul Christiansen, Steffen Hien, Cedric Brügmann, Dieter Jaksch, Veronika Eyring, Martin Kiffner, Mierk Schwabe

Quantum Physics

Error Mitigation in Bosonic Systems via Virtual Distillation

Leonardo Finocchiaro, Marco Robbio, Diogo Gomes et al. (+5 more)

Virtual distillation is a promising error-mitigation technique that exploits multiple copies of a noisy quantum state to estimate observables as if measured on a purified state. Although originally introduced in the context of bosonic many-body systems under the name of virtual cooling, its development and applications have largely focused on qubit-based quantum computation. Here, we establish a framework for virtual distillation in bosonic quantum information processing and continuous-variable quantum computing. Building on a diagonalization of cyclic shift operators implemented with passive linear-optical interferometers, we derive experimentally accessible protocols for estimating virtually distilled expectation values of observables relevant to bosonic architectures. In particular, we show how to recover noise-mitigated expectation values of number operators, phase-shift operators, and arbitrary quadratures from multi-copy measurements. For number operators, we further demonstrate the estimation of virtually distilled correlators of arbitrary order through the characteristic function of the photon-number distribution. We apply the framework to states affected by photon loss and dephasing, two of the dominant noise mechanisms in bosonic quantum computation, and quantify the resulting suppression of noise contributions. Our results extend virtual distillation beyond its original setting and provide a practical route toward error-mitigated measurements in bosonic quantum processors using experimentally available linear-optical resources.
Read the full abstract

All authors Leonardo Finocchiaro, Marco Robbio, Diogo Gomes, David Gunn, Adithi Udupa, Axel M. Eriksson, Leonardo Novo, Giulia Ferrini

Optics

When Reflection and Transmission Amplitude Coefficients Exceed Unity: Evanescent Waves, Resonances, and Optical Modes

Raúl de la Fuente

The reflection and transmission of propagating harmonic waves in linear optical systems have been widely discussed in the literature and are generally well understood. In passive systems involving only propagating waves, energy conservation constrains measurable quantities such as reflectance and transmittance, as well as the corresponding amplitude coefficients. However, when evanescent or damped waves are present, the reflection and transmission coefficients of the field amplitude may exhibit atypical behaviour, with the real or imaginary parts being much larger than one or even unbounded. In this study, we analyse this phenomenon in several simple optical configurations, including dielectric-metal interfaces, surface-plasmon-resonance prism couplers, plasmonic microcavities, step-index slab waveguides and prism-coupled waveguides. We demonstrate that these large amplitude coefficients naturally arise from extending reflection and transmission coefficients to evanescent or damped waves. On the other hand, they are not directly associated with measurable reflectance or transmittance and, therefore, do not conflict with energy conservation. Instead, they provide a useful formal description of resonant field enhancement, modal excitation and coupling processes in plasmonic and dielectric optical systems.
Read the full abstract

Biological Physics

Stochastic First-Passage Theory of HIV Viral Rebound Following Latent Reservoir Reactivation

Mesfin Asfaw Taye

In our earlier work, we modeled the stochastic initiation of HIV rebound by treating latent-cell reactivation as a Poisson-driven process during antiretroviral-therapy (ART) washout, immune modulation, and therapeutic perturbation~\cite{Taye2025CM}. That framework characterized activation survival, cumulative hazards, waiting-time laws, and expected viral-load trajectories. However, the endpoint observed in analytical treatment interruption (ATI) studies is not the hidden time of first successful reactivation. It is the first time at which plasma virus exceeds an assay-defined detection threshold. Here we reformulate post-treatment rebound as a stochastic first-passage problem, with $T_{\rm reb}=\inf\{t\ge t_w:V(t)\ge V_{\rm det}\}$. Successful reactivation events arrive with a time-dependent intensity, and each event seeds an exponentially expanding viral lineage. The total plasma viral load is therefore a Poisson shot-noise process, and rebound corresponds to its first threshold crossing. In the rare-reactivation regime, this crossing is dominated by the earliest successful lineage. Rebound timing then separates into two components: a stochastic waiting time for reservoir reactivation and a deterministic growth delay to detectability. This separation gives a shifted-hazard survival law and yields closed-form rebound-time distributions for constant activation, ART-washout-dependent activation, immune-periodic activation, Cox-process activation, and heterogeneous-reservoir activation. The same formulation also provides a likelihood suitable for the interval-censored sampling structure of ATI trials.
Read the full abstract

General Relativity and Quantum Cosmology

A stepping stone toward detecting gravitational wave memory: a cumulative analysis with the full $(\ell=2, m=0)$ spherical harmonic using events from GWTC-4.0 and GWTC-5.0

Maria Rosselló-Sastre, Sascha Husa, Yumeng Xu et al. (+3 more)

We perform Bayesian model selection to test for the presence of the $(\ell=2,m=0)$ spherical harmonic mode in gravitational wave events that have previously been identified as binary black hole mergers. As our signal model we use the quasi-circular, non-precessing IMRPhenomTHM_20 waveform model, which includes the oscillatory and displacement memory contributions. Including the oscillatory component of the (2,0) mode increases the signal-to-noise ratio and evidence for this mode, compared to testing only for the presence of gravitational wave memory. Our analysis thus constitutes a natural stepping stone toward detecting gravitational wave memory. We perform our analysis for the binary black hole signals identified in the GWTC-4.0 catalog, and for selected GWTC-5.0 events. In our Bayesian model comparison we find a cumulative $\log_{10}\mathcal{B}=1.38\pm0.79$ in favor of the presence of the (2,0) mode for the GWTC-4.0 catalog. We also stack the signal-to-noise ratio of the full (2,0) mode and of its individual contributions, obtaining results consistent with previous studies and reaching $\mathrm{SNR}_{\mathrm{memory}} = 0.89^{+0.29}_{-0.11}$ after approximately 7.5 months of O4a observations. In addition, we study the precessing candidate GW241127_061008, and find no additional evidence for the (2,0) mode when precession is included in IMRPhenomTPHM_20. Overall, our results provide an assessment of the observational support for the (2,0) mode in current gravitational wave data and allow us to discuss prospects for its future detection. We find that decisive statistical evidence will likely require a larger catalog, with an optimistic estimated number of events of $N_{\mathrm{events}} = 166^{+82}_{-55}$, based on the specific assumptions adopted in this work. We also expect that decisive evidence will require a more extensive waveform systematics study.
Read the full abstract

All authors Maria Rosselló-Sastre, Sascha Husa, Yumeng Xu, Jorge Valencia, Joan Llobera-Querol, Antoni Ramos-Buades

High Energy Physics (Theory)

Entropy bounds, Geroch process, and the sign of deformation parameter

Bijan Bagchi, Akshat Pandey, Parmest Roy et al. (+1 more)

Based on Geroch's process of dropping a system into a black hole from the vicinity of the horizon, we investigate in this paper the influence of deformation on the Bekenstein entropy bound both for (3+1) and (2+1) dimensions in the context of a generalized uncertainty principle (GUP). While providing a coherent framework that sets an upper limit on the entropy across dimensions we show, within a semiclassical treatment, that while a negative GUP deformation yields a universal relaxation of the bound, a positive deformation tightens it. Our results may be interpreted as a response to Planck-scale modifications of the near-horizon redshift.
Read the full abstract

All authors Bijan Bagchi, Akshat Pandey, Parmest Roy, Sauvik Sen

Astrophysics of Galaxies

FRANZ: Framework for analytical one-zone blastwave dynamics

Leonard E. C. Romano

(abridged) We develop a flexible analytical framework for modeling blastwave evolution in arbitrary environments and use it to investigate how large-scale galactic structure affects the dynamics and morphology of evolved SNRs and SBs. We introduce FRANZ (FRamework for ANalytical one-Zone blastwave dynamics), a modular thin-shell model that follows the local evolution of a shock-surface segment in environments characterized by arbitrary density, velocity and gravitational fields. After validating the model against well-established analytical results, we apply it to study the effects of vertical stratification, galactic shear and dense galactic substructure on blastwave evolution. FRANZ reproduces the classical evolution of blastwaves in uniform media while extending to complex environments. We derive criteria for disk break out in stratified media, characterize the timescales on which differential rotation deforms blastwaves and identify a new mechanism, by which it can suppress the momentum coupling in continuously-driven blastwaves. Interactions with dense filaments modify both shock-surface morphology and dynamics and confound the interpretation of the expansion history of observed remnants, which depends on the density distribution prior to the onset of explosions, which is fundamentally inaccessible from the observed state. In highly structured media with a high volume-filling factor of diffuse gas, ages inferred from the observed state may be systematically overestimated. FRANZ provides a computationally inexpensive and extensible framework for studying blastwaves in realistic galactic environments. It offers a useful complement to numerical simulations for interpreting observations of evolved SNRs and SBs and for developing improved models of stellar feedback in large-scale simulations.
Read the full abstract

Quantum Physics

Quantum orientation, Noether structure, composition of systems and operations

Heinz-Jürgen Schmidt

In this paper we argue that, in addition to the statistical structure of quantum theory, another structure, referred to here as the “Noether structure," is necessary to describe the composition of systems and to define completely positive operations. A Noether structure reflects the dual role of Hermitian operators as observables on the one hand and as generators of symmetry transformations on the other. This idea has been expressed in a similar form in the works of Alfsen and Shultz, who investigated the conditions under which the Jordan product can be extended to an associative product of operator algebras. Our investigations into the Noether structure and the composition of systems are limited to the finite-dimensional case and establish a connection to completely positive operations. In the case of pure operations, the latter can be characterized as orientation-preserving maps.
Read the full abstract

Soft Condensed Matter

Size Effect of Monovalent Ions on Polyelectrolyte Brushes

Xianggui Zhou, Nengjie Cao, Xiang-Meng Jia et al. (+2 more)

The conformation of polyelectrolyte (PE) brushes is highly sensitive to external conditions, particularly salt concentration and ion-specific effects. As salt concentration increases, PE brushes transition from an osmotic brush regime at low salt ($H \propto c_\mathrm{s}^{0}$) to a salted brush regime at high salt ($H \propto c_\mathrm{s}^{-1/3}$). However, deviations from this ideal scaling behavior are frequently observed in molecular simulations. In this work, we employ coarse-grained molecular dynamics simulations to systematically investigate how the sizes of counterions and co-ions affect the structural evolution and scaling behavior of PE brushes over a broad range of salt concentrations. Our results show that counterion size plays a dominant role in regulating ion penetration and coordination with PE monomers. At low salt concentration, smaller counterions penetrate more easily into the brush, leading to enhanced local charge compensation and stronger brush collapse. At high salt concentration, however, the brush height becomes largely insensitive to counterion size, while deviations from the classical scaling relation emerge. On the other hand, co-ion size mainly affects the system indirectly by modifying ion distributions and the local electrostatic environment. Smaller co-ions weaken local charge compensation and suppress brush collapse, with this effect becoming more pronounced at high salt concentration. When the sizes of counterions and co-ions are reduced simultaneously, the system exhibits a coupled response. Collectively, this work provides a microscopic understanding of how ion size and salt concentration jointly govern the structural response of PE brushes and the emergence of non-classical scaling behavior in realistic solution environments.
Read the full abstract

All authors Xianggui Zhou, Nengjie Cao, Xiang-Meng Jia, Jinyuan Mao, Jiajia Zhou

Quantum Physics

Photonic Cluster State Generation from a Quantum Dot Emitting in the Telecom C-band

Giora Peniakov, Reza Hekmati, Johannes Michl et al. (+9 more)

Photonic cluster states are a key resource for photonic quantum information processing. So far, deterministic generation of these states has been limited to the near-infrared wavelength range. To achieve quantum advantage in communication while maintaining compatibility with silicon photonics, operation in the telecom wavelength range is required. In this work, we demonstrate deterministic cluster state generation directly in the telecom C-band. This is achieved through repetitive excitation of a hole spin confined in an indium-arsenide quantum dot subjected to an external magnetic field. We characterize the quantum process that generates the cluster state by measuring its process map, obtaining a fidelity of $\mathrm{F} = 0.71 \pm 0.01$ to the ideal case. As part of this characterization, we observe spin–photon polarization entanglement with a negativity of $\mathrm{N} = 0.27 \pm 0.02$. The emitted photons exhibit indistinguishability of at least 83%, demonstrating the potential for future fusion gates necessary for photonic cluster state generation beyond linear connectivity.
Read the full abstract

All authors Giora Peniakov, Reza Hekmati, Johannes Michl, Mohamed Helal, Moritz Meinecke, Jochen Kaupp, Yorick Reum, Martin Kamp, Monika Emmerling, Andreas Theo Pfenning, Sven Hoefling, Tobias Huber-Loyola

Cosmology and Nongalactic Astrophysics

Collisionless damping of the gravitational instability in fuzzy dark matter: spectral shape and quantum-to-thermal crossover

Yosuke Matsumoto, Kohji Yoshikawa and Naoki Yoshida

We present a quantum-kinetic linear theory of the gravitational instability in the context of fuzzy dark matter universe. Starting from the Wigner transport equation, we apply Landau's approach to the linearized Wigner–Poisson system and derive a kinetic dispersion relation that incorporates quantum effects exactly by introducing the plasma dispersion function. The growth rate as a function of wavenumber is characterized by a dimensionless quantum-to-thermal ratio $\alpha = k_{\mathrm{qJ}}/k_{\mathrm J}$, where $k_{\mathrm{qJ}}$ and $k_{\mathrm J}$ represent the quantum and thermal Jeans wavenumbers, respectively. We derive an analytic expression for the spectral slope at the cutoff wavenumber, revealing that the spectral shape undergoes a sharp transition across $\alpha \sim 0.5$. This implies a crossover from a thermally dominated kinetic regime, in which collisionless damping occurs via phase mixing and Landau resonance, to a regime dominated by quantum pressure. By applying these results to fuzzy dark matter, we show that the cutoff scale and its spectral shape depend sensitively on both the particle mass and the initial velocity dispersion, suggesting a method for simultaneously constraining these parameters through observations of the matter power spectrum. This framework provides a theoretical basis for future studies on the transition from early-phase thermal states to the formation of Bose-Einstein condensates in galactic structures.
Read the full abstract

Astrophysics of Galaxies

Shared star formation in the Milky Way and Magellanic Clouds

Xunchuan Liu and Yu Cheng

We investigate the structural and evolutionary similarities between star formation patterns in different environments by comparing the dense clump populations in the Milky Way (MW) from the ATLASGAL survey with those from the Herschel HERITAGE survey in the Magellanic Clouds (MCs). Our analysis reveals that MW and MC clumps behave as physical analogs, sharing consistent dust temperature distributions, mass spectra, and luminosity evolutionary trends. We establish that the warmest MC clumps and the most distant MW clumps share an identical fiducial parent structure bounded by a natural spatial scale of $\sim 1$~parsec, serving as the direct precursors to open clusters. Closer MW clumps are resolved into discrete sub-clumps, whereas colder MC clumps suffer from peripheral envelope mass blending. Furthermore, the global spatial layout of clumps in the LMC and the MW shares a remarkably similar pattern when adjusting for galaxy size, suggesting a nested, hierarchical distribution. The clump-based star formation rates are calibrated to be $\sim 0.4~M_\odot\,\rm yr^{-1}$ for the LMC and $\sim 0.1~M_\odot\,\rm yr^{-1}$ for the SMC, confirming that the LMC is currently experiencing an active, ongoing star formation burst captured within a short ($< 10^6$~yr) snapshot timescale.
Read the full abstract

Optics

Ultra-high-speed line-scan Raman imaging

Qingyi Wu, Xusheng Tang, Francesco Masia et al. (+7 more)

Raman spectroscopic imaging has emerged as a potent tool due to its non-invasive nature and capability for chemical composition analysis. Line-scan Raman spectroscopy accelerates imaging speed by two orders of magnitude compared to point detection Raman methods. However, further enhancements in imaging speed were constrained by the readout speed of typically used charge-coupled device (CCD) spectroscopic detectors. We developed an ultra-fast line-scan Raman imaging technique based on recently available complementary metal-oxide-semiconductor (CMOS) detectors with low cost and read noise, and fast readout during exposure combined with a global shutter. Employing a high-efficiency transmissiongrating imaging spectrometer, we demonstrate imaging speeds up to two orders of magnitude faster than traditional line scan Raman imaging techniques and up to four orders of magnitude faster than point scan Raman methods, achieving Raman imaging up to 80 kHz spectral rate. We demonstrate that this technology is applicable to a variety of samples, including microplastics, biological cells, and tablets, creating images in an extremely short time frame, showcasing exceptional detection capabilities and the ability to reveal detailed information.
Read the full abstract

All authors Qingyi Wu, Xusheng Tang, Francesco Masia, Peng Liang, Hao Peng, Lindong Shang, Yuntong Wang, Yue Qu, Wolfgang Langbein, Bei Li

Mesoscale and Nanoscale Physics

A Unified Electrostatic-to-Spin Framework for Asymmetric Multi-Gate CMOS Quantum Devices

Zeheng Wang, Yan Liu, Yue Hao et al. (+1 more)

In advanced complementary metal-oxide-semiconductor (CMOS) quantum chips, compact gate stacks make it difficult to connect lithographic geometry, electrostatic confinement and many-electron spin filling in one transparent model. This connection is central to design-technology co-optimization (DTCO). Here we develop a reduced-order analytical framework for asymmetric multigate silicon quantum-dot devices. Its electrostatic core, the Poisson-kernel coupled-interface Green-function (PK-GF) model, agrees with an independent finite-volume solution at the millivolt scale for the matched two-dimensional problem, without fitting to that solution. We then pass the gate-derived confinement, rather than a harmonic or fitted potential, to a spin-valley many-body calculation for a jellybean quantum dot with N = 2-17 electrons at B = 5 T. The unrestricted Hartree-Fock (UHF) solution supports occupation-dependent, Wigner-molecule-like charge localization but likely overestimates spin polarization. Complete active-space configuration interaction (CASCI) supports a low-spin branch within the tested active spaces, which aligns with the experiments. The workflow therefore connects CMOS layout, device electrostatics, and potential-determined quantum observables, providing an auditable modelling layer for CMOS-based qubit design and DTCO.
Read the full abstract

All authors Zeheng Wang, Yan Liu, Yue Hao, Genquan Han

Instrumentation and Methods for Astrophysics

Star-Planet Interactions: The Instrumentation Perspective

H. Korhonen, P. Figueira, B. Montet et al. (+4 more)

Star-Planet Interactions (SPIs) produce observable phenomena across the electromagnetic spectrum, from X-ray and ultraviolet emission tracing magnetic activity and atmospheric escape to optical, infrared, and radio signatures probing stellar variability, planetary atmospheres, and magnetospheric interactions. This work reviews the current observational capabilities for SPI research, focusing on the instruments and facilities currently used, or technically capable of being used, for SPI studies. Particular emphasis is placed on the instrumental characteristics required to detect often weak and transient SPI signatures, as well as on the observational challenges associated with such measurements. The chapter concludes with an outlook on upcoming facilities that are expected to enhance our ability to detect, characterise, and understand SPI phenomena in the coming years.
Read the full abstract

All authors H. Korhonen, P. Figueira, B. Montet, S.P. Jarvinen, H. Vedantham, S. Narendranath, P. Chaturvedi

Quantum Gases

Bloch-sphere rotations in driven double-well for ultracold atoms

Michele Modugno, Marco Fattori and Giulio Pettini

We show that, by using suitable protocols for a non-interacting condensate in a driven double-well, one can achieve controlled rotations about arbitrary axes in the equatorial plane of the Bloch sphere, composed with fast rotations about the $z$-axis. Specifically, we investigate the dynamics induced by a spatially linear time-periodic potential, by means of numerical simulations. We also provide an explicit two-level model that accurately captures the microscopic evolution of the driven system, with the full time-dependent evolution operator obtained using a Floquet-based approach. The analysis is carried out using as a reference a recently realized experimental platform consisting of arrays of double-well potentials based on Beat-Note Superlattices, to which the proposed control scheme is directly applicable.
Read the full abstract

High Energy Physics (Phenomenology)

Pion Distribution Amplitudes from Functional QCD

Lei Chang, Wei-jie Fu, Chuang Huang et al. (+2 more)

We present the first functional QCD calculation of the pion distribution amplitude (DA) using the large-momentum effective theory within the functional renormalisation group (fRG) approach. With only the strong coupling and current quark masses as inputs, we compute the quasi-DA from first-principles QCD correlation functions. By pushing the pion momentum up to $P_z = 4.5\ \mathrm{GeV}$, the quasi-DA becomes fully saturated, rendering the extrapolation errors to the light-cone limit negligible. The resulting second-order moment $\langle \xi^2 \rangle_\pi = 0.267$ is significantly smaller than existing lattice-LaMET determinations and lies in a range consistent with other nonperturbative approaches.
Read the full abstract

All authors Lei Chang, Wei-jie Fu, Chuang Huang, Jan M. Pawlowski, Yang-yang Tan

Soft Condensed Matter

Unveiling Structural Bottlenecks of Dynamic Disorder in a Density-Tunable Glass Former: From Strong to Fragile Regimes

Shubham Kumar and Shinji Saito

Fragility characterizes how rapidly a glass-forming liquid slows down upon supercooling, but whether strong and fragile behaviors arise from the same microscopic relaxation mechanism remains unclear. Here, we address this question using a density-tunable soft-repulsive binary mixture spanning distinct fragility regimes and analyze particle jump dynamics within the framework of dynamic disorder. Across these regimes, we show that increasing fragility leads to progressively broader cage-lifetime distributions and increasingly non-exponential survival probabilities, revealing non-Poisson cage-to-jump statistics governed by fluctuating jump rates and slowly evolving structural variables. To characterize their structural origin, we first identify the neighbor ranks most strongly coupled to jump motion using Kullback-Leibler divergence and Pearson correlation analyses. We then introduce a structural slowness parameter that combines these neighbor-distance fluctuations into a reduced slow coordinate for constructing the slow-fluctuation survival probability. A comparison with the actual survival probability shows that localized neighbor-distance fluctuations control the jump rate in the strong regime, whereas extended neighbor rearrangements become relevant in the intermediate and fragile regimes, increasing the effective dimensionality of the slow-variable space. In the fragile regime, distance-based descriptors alone become insufficient at the lowest temperature, where the Voronoi free volume captures additional cage-volume fluctuations in the rate-controlling slow variable. Point-to-set correlations grow with fragility, but the spatial extent of the slow variables exceeds the point-to-set length. These results show that fragility changes the structural bottleneck for microscopic rate fluctuations, linking dynamic disorder and multidimensional slow variables.
Read the full abstract

Chemical Physics

Anomalous Peak Formation in the Second Stability Zone of Quadrupole Mass Filters: Role of Non-linear Resonances Induced by Single Rod Defects

Archisman Sinha, Pintu Mandal and Nabanita Deb

Operating a quadrupole mass filter (QMF) within its second stability zone offers superior mass resolving power but introduces extreme sensitivity to structural imperfections. While symmetric misalignments are well-documented, this work combines analytical modeling with SIMION trajectory simulations to investigate the unaddressed electrodynamic impact of a completely localized, asymmetric defect on a single rod. Unlike diagonally symmetric perturbations, which reduce the four-fold rotational symmetry to two-fold symmetry while maintaining a smooth stability landscape, a single-rod defect breaks the remaining symmetry, giving rise to pronounced transmission ridges within the second stability zone. Spatial multipole expansion reveals that this structural breakdown injects odd-parity harmonics – dominated by the hexapole A3 field – which couple the orthogonal transverse equations of motion. By tracking secular indices through explicit zone-II Floquet projection mappings, we demonstrate that these asymmetric fields drive destructive, higher-order nonlinear secular resonances. Ions traversing these precise parametric coordinates undergo rapid amplitude growth and collide with adjacent electrodes, establishing critical geometric tolerance frameworks and operating conditions for high-performance mass spectrometry.
Read the full abstract

Physics and Society

Bursty Arrivals, Smooth Sojourns: Non-Poissonian Temporal Dynamics in a Logistics Warehouse

Alfonso de Miguel-Arribas and Yamir Moreno

Warehouses are central nodes in logistics networks: they buffer material flows, synchronize heterogeneous actors, and absorb temporal mismatches between inbound and outbound operations. Yet most warehouse analyses still rely on aggregate performance indicators or on queueing assumptions in which event timing is stationary and approximately memoryless. Here we use one month of high-resolution pallet-level data from a large Spanish warehouse to characterize arrivals, departures, and outbound residence times from a statistical-physics perspective. Inter-arrival and inter-departure times are strongly heterogeneous and compatible with heavy-tailed, non-Poissonian behavior, whereas outbound sojourn times are more naturally described by a log-normal distribution, suggesting constrained service mechanisms with a characteristic operational scale. Disaggregation by logistics flow reveals systematic differences in burstiness, memory, and distributional similarity. A renewal-based aging analysis uncovers recurrent weekly accumulation and clearance cycles in the outbound buffer zone. Finally, a Little's-Law-inspired activity–sojourn scaling identifies two operational regimes: a near-linear baseline under regular turnover and a reproducible off-baseline branch associated with weekend accumulation and Monday dispatches. These results provide a compact diagnostic framework for temporal complexity in warehouse operations and show how limited but high-resolution industrial data can reveal operational structure invisible to aggregate throughput statistics.
Read the full abstract