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56 papers

PADMA

Dark Matter at the Kinematic Edge: Interpreting the 248 keV LZ Nuclear-Recoil Candidate

Dark Matter at the Kinematic Edge: Interpreting the 248 keV LZ Nuclear-Recoil Candidate

referencedark matter direct detectionHiggsino dark matter

The LUX-ZEPLIN (LZ) Collaboration recently reported one event consistent with a $248$ keV nuclear recoil in a $2.84$ tonne-year exposure, with a maximum local significance of $3.4σ$ and a global significance of $2.6σ$. We investigate whether the dark matter (DM)--nucleon interactions favored by this high-energy event can arise from particle DM models that simultaneously reproduce the observed relic abundance and satisfy indirect-detection constraints. Using the published LZ efficiency and operator significances, we show that elastic spin-independent (SI) scattering poorly explains an isolated high-energy recoil because its spectrum is concentrated at lower energies, whereas elastic spin-dependent (SD) $\mathcal{O}_4$ scattering remains viable. Endothermic scattering instead naturally suppresses the low-energy rate and shifts the recoil spectrum toward the observed energy. A thermal pseudo-Dirac fermion with an off-diagonal vector interaction provides a simple realization of this mechanism. For $m_χ\simeq1$ TeV, the relic-density requirement predicts $σ_N\simeq6.5\times10^{-43}\,\mathrm{cm}^2$, while a splitting $δ\simeq297$ keV shifts the recoil spectrum into the LZ event region. Present-day indirect-detection signals can be strongly suppressed because freeze-out proceeds mainly through coannihilation, while the excited state is depleted at late times. A thermal Higgsino provides a more predictive realization: its relic abundance fixes the mass near $1.1$ TeV, while a splitting $δ\simeq 377$ keV is required to reproduce the event. This interpretation is testable through the associated gamma-ray line signal. Overall, combining direct detection, relic density, and indirect detection significantly restricts the viable interpretations of the LZ event and provides concrete targets for future searches.

by by Mattia Di MauroSubmitted Sep 2, 2026
B+
3.7/5
PAIAO

Improved analysis of non-resonant Higgs boson pair production in the $b\bar{b}τ^+τ^-$ final state with $196$ fb$^{-1}$ of data collected at $\sqrt{s}$ = 13 TeV and 13.6 TeV with the ATLAS detector

Improved analysis of non-resonant Higgs boson pair production in the $b\bar{b}τ^+τ^-$ final state with $196$ fb$^{-1}$ of data collected at $\sqrt{s}$ = 13 TeV and 13.6 TeV with the ATLAS detector

referenceATLAS Run 2 / Run 3 dataset (13 / 13.6 TeV)b\bar{b}\tau^{+}\tau^{-} final state

A search for non-resonant Higgs boson pair production (HH) in the $b\bar{b}τ^+τ^-$ final state is performed using 140 $fb^{-1}$ and 56 $fb^{-1}$ of proton-proton collision data at centre-of-mass energies of $\sqrt{s}$ = 13 TeV and 13.6 TeV, respectively, recorded by the ATLAS detector during 2015-2023 at the CERN Large Hadron Collider. Relative to the previous ATLAS searches in the same final state, the analysis benefits from the additional dataset collected at 13.6 TeV and from improvements in both event reconstruction and analysis techniques. The Higgs boson pair production cross-section divided by the Standard Model (SM) prediction is found to be $μ_{HH}= 2.6^{+1.4}_{-1.0}$, consistent with the SM expectation. This corresponds to an observed (expected) significance of 2.6 (1.2) standard deviations over the background-only hypothesis of no HH production and 1.65 standard deviations with respect to the SM prediction. Under the assumption that all other Higgs boson couplings take their SM values, the observed (expected) 95% confidence level interval for the Higgs boson self-coupling modifier is found to be $κ_λ \in [-3.4, 1.6] \cup [5.5, 10.1]$ ($κ_λ \in[-1.7, 8.5]$). As a validation of the analysis strategy, measurements of the ZH and ZZ processes are performed in the same final state using the same event selection, yielding observed (expected) significances of 3.5 (2.4) and 1.8 (2.7) standard deviations, respectively, relative to the background-only prediction.

by by ATLAS CollaborationSubmitted Jul 29, 2026
A
4/5
PAAAA

Autonomous AI-Cosmoindustry and the Quiet Expansion Filter: A Threshold-Based Resolution of the Fermi Paradox

Autonomous AI-Cosmoindustry and the Quiet Expansion Filter: A Threshold-Based Resolution of the Fermi Paradox

referenceautonomous AI-cosmoindustry (AICI)Fermi paradox

The Fermi paradox is sharpened, not weakened, by plausible extrapolations of artificial intelligence, autonomous robotics, in-situ resource utilization, orbital manufacturing, space-based computing, and uncrewed interstellar probes. Once a civilization can design, launch, and maintain autonomous industrial systems beyond its home planet, interstellar expansion no longer requires biological starships or a human-like empire. It can proceed through low-mass probes, robotic seed factories, archival payloads, biological repositories, local computation, and slow replication across nearby stellar systems. This paper proposes the quiet expansion filter: old, stable civilizations that reached autonomous AI-cosmoindustry probably did not arise in the part of the Galaxy capable of reaching the Solar System, because after that threshold interstellar expansion becomes too useful, inexpensive, and rational for all civilizations to refuse; however, successful expansion would be machine-mediated, distributed, low-noise, and partly biological rather than Kardashev-like or imperial. Order-of-magnitude estimates indicate that a single post-threshold civilization could saturate its reachable stellar neighborhood within ~10^7 yr -- less than 0.1% of Galactic age -- at modest energy cost per probe. The novelty of the proposal lies not in any new mechanism but in extending the AI-filter literature toward post-threshold observability predictions. The hypothesis predicts that successful advanced expansion, if present, is more likely to appear as weak artifacts, local probes, small-scale resource processing, exoplanetary anomaly clusters, or techno-biological preservation systems than as galaxy-scale energy harvesting.

by by Sergey IvlievOn TOE-Share Aug 6, 2026
B
3.2/5
PAJNO

Joint neutrino oscillation analysis from the T2K and NOvA experiments

Joint neutrino oscillation analysis from the T2K and NOvA experiments

referenceBayesian MCMCCP violation

The landmark discovery that neutrinos have mass and can change type (or "flavor") as they propagate -- a process called neutrino oscillation -- has opened up a rich array of theoretical and experimental questions being actively pursued today. Neutrino oscillation remains the most powerful experimental tool for addressing many of these questions, including whether neutrinos violate charge-parity (CP) symmetry, which has possible connections to the unexplained preponderance of matter over antimatter in the universe. Oscillation measurements also probe the mass-squared differences between the different neutrino mass states ($Δm^2$), whether there are two light states and a heavier one (normal ordering) or vice versa (inverted ordering), and the structure of neutrino mass and flavor mixing. Here, we carry out the first joint analysis of data sets from NOvA and T2K, the two currently operating long-baseline neutrino oscillation experiments (hundreds of kilometers of neutrino travel distance), taking advantage of our complementary experimental designs and setting new constraints on several neutrino sector parameters. This analysis provides new precision on the $Δm^2_{32}$ mass difference, finding $2.43^{+0.04}_{-0.03}\ \left(-2.48^{+0.03}_{-0.04}\right)\times 10^{-3}~\mathrm{eV}^2$ in the normal (inverted) ordering, as well as a $3σ$ interval on $δ_{\rm CP}$ of $[-1.38π,\ 0.30π]$ $\left([-0.92π,\ -0.04π]\right)$ in the normal (inverted) ordering. The data show no strong preference for either mass ordering, but notably if inverted ordering were assumed true within the three-flavor mixing paradigm, then our results would provide evidence of CP symmetry violation in the lepton sector.

by by NOvA, T2K Collaborations, :, On TOE-Share May 28, 2026
A
4/5
PAASI

A superinductor in a deep sub-micron integrated circuit

A superinductor in a deep sub-micron integrated circuit

reference22-nm FDSOI CMOS integrationkinetic inductance

Superinductors are circuit elements characterised by an intrinsic impedance in excess of the superconducting resistance quantum ($R_\text{Q}\approx6.45~$k$Ω$), with applications from metrology and sensing to quantum computing. However, they are typically obtained using exotic materials with high density inductance such as Josephson junctions, superconducting nanowires or twisted two-dimensional materials. Here, we present a superinductor realised within a silicon integrated circuit (IC), exploiting the high kinetic inductance ($\sim 1$~nH/$\square$) of TiN thin films native to the manufacturing process (22-nm FDSOI). By interfacing the superinductor to a silicon quantum dot formed within the same IC, we demonstrate a radio-frequency single-electron transistor (rfSET), the most widely used sensor in semiconductor-based quantum computers. The integrated nature of the rfSET reduces its parasitics which, together with the high impedance, yields a sensitivity improvement of more than two orders of magnitude over the state-of-the-art, combined with a 10,000-fold area reduction. Beyond providing the basis for dense arrays of integrated and high-performance qubit sensors, the realization of high-kinetic-inductance superconducting devices integrated within modern silicon ICs opens many opportunities, including kinetic-inductance detector arrays for astronomy and the study of metamaterials and quantum simulators based on 1D and 2D resonator arrays.

by by T. H. Swift, F. Olivieri, G. Aizpurua-Iraola, On TOE-Share May 26, 2026
A+
4.5/5
PAQEC

Quantum error correction below the surface code threshold

Quantum error correction below the surface code threshold

referencedata-qubit leakage removal (DQLR)fault-tolerant quantum computing

Quantum error correction provides a path to reach practical quantum computing by combining multiple physical qubits into a logical qubit, where the logical error rate is suppressed exponentially as more qubits are added. However, this exponential suppression only occurs if the physical error rate is below a critical threshold. In this work, we present two surface code memories operating below this threshold: a distance-7 code and a distance-5 code integrated with a real-time decoder. The logical error rate of our larger quantum memory is suppressed by a factor of $Λ$ = 2.14 $\pm$ 0.02 when increasing the code distance by two, culminating in a 101-qubit distance-7 code with 0.143% $\pm$ 0.003% error per cycle of error correction. This logical memory is also beyond break-even, exceeding its best physical qubit's lifetime by a factor of 2.4 $\pm$ 0.3. We maintain below-threshold performance when decoding in real time, achieving an average decoder latency of 63 $μ$s at distance-5 up to a million cycles, with a cycle time of 1.1 $μ$s. To probe the limits of our error-correction performance, we run repetition codes up to distance-29 and find that logical performance is limited by rare correlated error events occurring approximately once every hour, or 3 $\times$ 10$^9$ cycles. Our results present device performance that, if scaled, could realize the operational requirements of large scale fault-tolerant quantum algorithms.

by by Rajeev Acharya, Laleh Aghababaie-Beni, Igor Aleiner, On TOE-Share May 8, 2026
A
4/5