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arXiv Open Access 2026
Illuminating the Physics of Cosmic Origin and Evolution: A UK Space Frontiers 2035 White Paper

Florian Beutler, Eva-Maria Mueller, Seshadri Nadathur et al.

Understanding the Universe's origins and evolution remains one of the most fundamental challenges in modern cosmology. This white paper explores three key science priorities in this field: unravelling the physics of cosmic inflation, investigating the accelerating expansion of the Universe, and precisely measuring the sum of the neutrino masses. Achieving these goals requires a dedicated survey to map the large-scale structure at high redshift in unprecedented detail. We describe how this can be achieved through a mission concept called SIRMOS, providing a high-throughput, highly multiplexed spectroscopic capability to obtain accurate redshifts for over 100 million galaxies over a wide sky area. Such a survey would leverage the deepest existing wide-area photometric catalogues for targeting, with spectra offering continuous 1.25-2.5~$μ$m wavelength coverage at moderate resolution, allowing precise redshift measurements in the $1<z<4$ range with minimal bias. We outline the scientific opportunities this presents. Recent years have seen significant advances in instrumentation, including digital micromirror devices, complex telescope mirrors, large detector arrays, and data processing pipelines. While these technologies have been demonstrated in terrestrial applications, such a survey is a unique opportunity to apply these proven capabilities in space to address fundamental questions in cosmology. Participation in such a mission will simultaneously deliver a compelling science case, help align UK Space Agency and STFC strategies, demonstrate the UK's growing capability in end-to-end space missions, and strengthen the national space economy through high-value industrial participation.

en astro-ph.IM, astro-ph.CO
S2 Open Access 2019
Neutrino–nuclear responses for astro-neutrinos, single beta decays and double beta decays

H. Ejiri, J. Suhonen, K. Zuber

Abstract Neutrino–nuclear responses associated with astro-neutrinos, single beta decays and double beta decays are crucial in studies of neutrino properties of interest for astro-particle physics. The present report reviews briefly recent studies of the neutrino–nuclear responses from both experimental and theoretical points of view in order to obtain a consistent understanding of the many facets of the neutrino–nuclear responses. Subjects discussed in this review include (i) experimental studies of neutrino–nuclear responses by means of single beta decays, charge-exchange nuclear reactions, muon- photon- and neutrino–nuclear reactions, and nucleon-transfer reactions, (ii) implications of and discussions on neutrino–nuclear responses for single beta decays, for astro-neutrinos, and for astro-neutrino nucleosynthesis, (iii) theoretical aspects of neutrino–nuclear responses for beta and double beta decays, for nuclear muon capture and for neutrino–nucleus scattering, and (iv) critical discussions on nucleonic and non-nucleonic spin–isospin correlations and renormalization (quenching or enhancement) effects on the axial weak coupling. Remarks are given on perspectives of experimental and theoretical studies of the neutrino–nuclear responses and on future experiments of double beta decays.

207 sitasi en Physics
arXiv Open Access 2025
Light scalars in light of UV/IR mixing: classicalization via synergy between Vainshtein and chameleon screenings

Florian Nortier

Effective field theories featuring light scalar fields play a pivotal role in addressing fundamental questions in (astro)particle physics and cosmology. However, such theories often confront hierarchy problems in the absence of a symmetry. Self-completion via classicalization offers a non-Wilsonian approach to ultraviolet (UV) completion, wherein new scalar self-interactions involving derivatives give rise to Vainshtein-like screening around energy-momentum sources. Rather than introducing new UV degrees of freedom to restore unitarity at high energies, these theories reshuffle their infrared (IR) degrees of freedom by generating extended semi-classical objects -- referred to as classicalons -- which decay into a multitude of soft particles. This mechanism incorporates non-localizable fields, thereby realizing a form of UV/IR mixing that is analogous to the dynamics of black holes in gravitational theories. In this article, having reviewed the fundamental principles of classicalization with a simple k-essence model, we then argue the necessity of maintaining a little hierarchy between the scalar mass and the scale of the first new resonances, thereby illustrating the impact of UV/IR mixing on hierarchy problems. Additionally, we investigate the effects of a scalar potential and couplings to fermions on the Vainshtein screening mechanism. We discuss that a chameleon-like screening mechanism must accompany the Vainshtein screening to preserve the integrity of classicalon solutions.

en hep-ph, astro-ph.CO
arXiv Open Access 2025
Deep Learning in Astrophysics

Yuan-Sen Ting

Deep learning has generated diverse perspectives in astronomy, with ongoing discussions between proponents and skeptics motivating this review. We examine how neural networks complement classical statistics, extending our data analytical toolkit for modern surveys. Astronomy offers unique opportunities through encoding physical symmetries, conservation laws, and differential equations directly into architectures, creating models that generalize beyond training data. Yet challenges persist as unlabeled observations number in billions while confirmed examples with known properties remain scarce and expensive. This review demonstrates how deep learning incorporates domain knowledge through architectural design, with built-in assumptions guiding models toward physically meaningful solutions. We evaluate where these methods offer genuine advances versus claims requiring careful scrutiny. - Neural architectures overcome trade-offs between scalability, expressivity, and data efficiency by encoding physical symmetries and conservation laws into network structure, enabling learning from limited labeled data. - Simulation-based inference and anomaly detection extract information from complex, non-Gaussian distributions where analytical likelihoods fail, enabling field-level cosmological analysis and systematic discovery of rare phenomena. - Multi-scale neural modeling bridges resolution gaps in astronomical simulations, learning effective subgrid physics from expensive high-fidelity runs to enhance large-volume calculations where direct computation remains prohibitive. - Emerging paradigms-reinforcement learning for telescope operations, foundation models learning from minimal examples, and large language model agents for research automation-show promise though are still developing in astronomical applications.

en astro-ph.IM, astro-ph.CO
arXiv Open Access 2025
Constraining Cosmology with Double-source-plane Strong Gravitational Lenses from the AGEL Survey

Duncan J. Bowden, Nandini Sahu, Anowar J. Shajib et al.

Double-source-plane strong gravitational lenses (DSPLs), with two sources at different redshifts, are independent cosmological probes of the dark energy equation of state parameter $w$ and the matter density parameter $Ω_{\rm m}$. We present the lens model for the DSPL AGEL035346$-$170639 and infer cosmological constraints from this system for flat $Λ$ cold dark matter and flat $w$CDM cosmologies. From the joint posterior of $w$ and $Ω_{\rm m}$ in the flat $w$CDM cosmology, we extract the following median values and 1$σ$ uncertainties: $w = -1.52^{+0.49}_{-0.33}$ and $Ω_{\rm m} = 0.192^{+0.305}_{-0.131}$ from AGEL0353 alone. Combining our measurements with two previously analyzed DSPLs, we present the joint constraint on these parameters from a sample of three, the largest galaxy-scale DSPL sample used for cosmological measurement to date. The combined precision of $w$ from three DSPLs is higher by 15% over AGEL0353 alone. Combining DSPL and cosmic microwave background (CMB) measurements improves the precision of $w$ from CMB-only constraints by 39%, demonstrating the complementarity of DSPLs with the CMB. Despite their promising constraining power, DSPLs are limited by sample size, with only a handful discovered so far. Although ongoing and near-future wide-area sky surveys will increase the number of known DSPLs by up to two orders of magnitude, these systems will still require dedicated high-resolution imaging and spectroscopic follow-ups like those presented in this paper. Our ASTRO 3D Galaxy Evolution with Lenses collaboration is undertaking such follow-up campaigns for several newly discovered DSPLs and will provide cosmological measurements from larger samples of DSPLs in the future.

en astro-ph.CO
arXiv Open Access 2024
Updates on the density of states method in finite temperature symplectic gauge theories

David Mason, Ed Bennett, Biagio Lucini et al.

First-order phase transitions in the early universe have rich phenomenological implications, such as the production of a potentially detectable signal of stochastic relic background gravitational waves. The hypothesis that new, strongly coupled dynamics, hiding in a new dark sector, could be detected in this way, via the telltale signs of its confinement/deconfinement phase transition, provides a fascinating opportunity for interdisciplinary synergy between lattice field theory and astro-particle physics. But its viability relies on completing the challenging task of providing accurate theoretical predictions for the parameters characterising the strongly coupled theory. Density of states methods, and in particular the linear logarithmic relaxation (LLR) method, can be used to address the intrinsic numerical difficulties that arise due the meta-stable dynamics in the vicinity of the critical point. For example, it allows one to obtain accurate determinations of thermodynamic observables that are otherwise inaccessible, such as the free energy. In this contribution, we present an update on results of the analysis of the finite temperature deconfinement phase transition in a pure gauge theory with a symplectic gauge group, $Sp(4)$, by using the LLR method. We present a first analysis of the properties of the transition in the thermodynamic limit, and provide a road map for future work, including a brief preliminary discussion that will inform future publications.

en hep-lat, astro-ph.CO
arXiv Open Access 2023
Constraints on monopole-dipole potential from the tests of gravity

Tanmay Kumar Poddar, Debashis Pachhar

Ultralight Axion Like Particle (ALP) can mediate a long range monopole-dipole macroscopic force between Earth and Sun if Earth is treated as a polarized source. There are about $10^{42}$ number of polarized electrons in Earth due to the presence of the geomagnetic field. The monopole-dipole interactions between electrons in Earth and nucleons in Sun can influence the perihelion precession of Earth, gravitational light bending and Shapiro time delay. The contribution of monopole-dipole potential is limited to be no larger than the measurement uncertainty. We obtain the first bound on monopole-dipole strength from single astrophysical observations. The perihelion precession of Earth puts the stronger bound on monopole-dipole coupling strength as $g_Sg_P\lesssim 1.75\times 10^{-16}$ for the ALP of mass $m_a\lesssim 1.35\times 10^{-18}~\rm{eV}$. We also obtain constraints on monopole-dipole coupling strength as $g_Sg_P\lesssim 5.61\times 10^{-38}$ from two different astrophysical observations such as the perihelion precession of the planet and the red giant branch. The bound is three orders of magnitude stronger than the Eöt-Wash experiment and one order of magnitude stronger than the $(\rm{Lab})^N_S\times (\rm{Astro})^e_P$ limit.

en hep-ph, astro-ph.CO
S2 Open Access 2021
Radiation Therapy for Small-Cell Lung Cancer: ASCO Guideline Endorsement of an ASTRO Guideline.

M. Daly, Nofisat Ismaila, R. Decker et al.

PURPOSE The American Society for Radiation Oncology (ASTRO) produced an evidence-based guideline on radiation therapy (RT) for small-cell lung cancer (SCLC). Because of the relevance of this topic to ASCO membership, ASCO reviewed the guideline, applying a set of procedures and policies used to critically examine guidelines developed by other organizations. METHODS The ASTRO guideline on RT for SCLC was reviewed for developmental rigor by methodologists. Then, an ASCO Expert Panel reviewed the content and the recommendations. RESULTS The ASCO Expert Panel determined that the recommendations from ASTRO guideline on RT for SCLC, published in June 2020, are clear, thorough, and based upon the most relevant scientific evidence. ASCO endorsed ASTRO guideline on RT for SCLC with a few discussion points. RECOMMENDATIONS Recommendations addressed thoracic radiotherapy for limited-stage SCLC, role of stereotactic body radiotherapy in stage I or II node-negative SCLC, prophylactic cranial radiotherapy, and thoracic consolidation for extensive-stage SCLC.Additional information is available at www.asco.org/thoracic-cancer-guidelines.

49 sitasi en Medicine
S2 Open Access 2022
Astro-mT5: Entity Extraction from Astrophysics Literature using mT5 Language Model

Madhusudan Ghosh, Payel Santra, SK Asif Iqbal et al.

Scientific research requires reading and extracting relevant information from existing scientific literature in an effective way. To gain insights over a collection of such scientific documents, extraction of entities and recognizing their types is considered to be one of the important tasks. Numerous studies have been conducted in this area of research. In our study, we introduce a framework for entity recognition and identification of NASA astrophysics dataset, which was published as a part of the DEAL SharedTask. We use a pre-trained multilingual model, based on a natural language processing framework for the given sequence labeling tasks. Experiments show that our model, Astro-mT5, out-performs the existing baseline in astrophysics related information extraction.

S2 Open Access 2022
K-ASTRO: Structure-Aware Adaptation of LLMs for Code Vulnerability Detection

Yifan Zhang, Junwen Yang, Huihui Dong et al.

Large Language Models (LLMs) are transforming software engineering tasks, including code vulnerability detection-a critical area of software security. However, existing methods often rely on resource-intensive models or graph-based techniques, limiting their accessibility and practicality. This paper introduces K-ASTRO, a lightweight Transformer model that combines semantic embeddings from LLMs with structural features of Abstract Syntax Trees (ASTs) to improve both efficiency and accuracy in code vulnerability detection. Our approach introduces an AST-based augmentation technique inspired by mutation testing, a structure-aware attention mechanism that incorporates augmented AST features, and a joint adaptation pipeline to unify code semantics and syntax. Experimental results on three large-scale datasets, including BigVul, DiverseVul, and PrimeVul-demonstrate state-of-the-art performance while enabling rapid inference on CPUs with minimal training time. By offering a scalable, interpretable, and efficient solution, K-ASTRO bridges the gap between LLM advancements and practical software vulnerability detection, providing open-sourced tools to foster further research.

5 sitasi en Computer Science
S2 Open Access 2022
Astro-COLIBRI 2—An Advanced Platform for Real-Time Multi-Messenger Discoveries

P. Reichherzer, F. Schüssler, V. Lefranc et al.

The study of flaring astrophysical events in the multi-messenger approach requires instantaneous follow-up observations to better understand the nature of these events through complementary observational data. We present Astro-COLIBRI as a platform that integrates specific tools in the real-time multi-messenger ecosystem. The Astro-COLIBRI platform bundles and evaluates alerts about transients from various channels. It further automates the coordination of follow-up observations by providing and linking detailed information through its comprehensible graphical user interface. We present the functionalities with documented examples of Astro-COLIBRI usage through the community since its public release in August 2021. We highlight the use cases of Astro-COLIBRI for planning follow-up observations by professional and amateur astronomers, as well as checking predictions from theoretical models.

4 sitasi en Physics
S2 Open Access 2021
Astro-COLIBRI—The COincidence LIBrary for Real-time Inquiry for Multimessenger Astrophysics

P. Reichherzer, F. Schüssler, V. Lefranc et al.

Astro-COLIBRI is a novel tool that evaluates alerts of transient observations in real time, filters them by user-specified criteria, and puts them into their multiwavelength and multimessenger context. Through fast generation of an overview of persistent sources as well as transient events in the relevant phase space, Astro-COLIBRI contributes to an enhanced discovery potential of both serendipitous and follow-up observations of the transient sky. The software’s architecture comprises a Representational State Transfer Application Programming Interface, both a static and a real-time database, a cloud-based alert system, as well as a website and apps for iOS and Android as clients for users. The latter provide a graphical representation with a summary of the relevant data to allow for the fast identification of interesting phenomena along with an assessment of observing conditions at a large selection of observatories around the world.

19 sitasi en Physics
S2 Open Access 2020
ACR–ASTRO Practice Parameter for the Performance of Stereotactic Body Radiation Therapy

S. Chao, L. Dad, L. Dawson et al.

Aim/Objectives/Background: To standardize the practice of stereotactic body radiation therapy (SBRT), the American College of Radiology (ACR) and the American Society for Radiation Oncology (ASTRO) cooperatively developed the practice parameter for SBRT. SBRT is a treatment technique that delivers radiation dose to a well-defined extracranial target in 5 fractions or less and usually employs a higher dose per fraction than used in conventional radiation. Methods: The ACR–ASTRO Practice Parameter for the Performance of Stereotactic Body Radiation Therapy was revised according to the process described on the ACR website (“The Process for Developing ACR Practice Parameters and Technical Standards,” www.acr.org/ClinicalResources/Practice-Parameters-and-Technical-Standards) by the Committee on Practice Parameters of the ACR Commission on Radiation Oncology in collaboration with the ASTRO. Both societies then reviewed and approved the document. Results: Given the complexities of SBRT, a separate document was created to develop a technical standard for the medical physics of SBRT (ACR–AAPM Technical Standard for Medical Physics Performance Monitoring of Stereotactic Body Radiation Therapy). Workflow, qualifications and responsibilities of personnel, specifications, documentation, quality control/safety/improvement, simulation/treatment, and follow-up were addressed in this practice parameter. Conclusions: This practice parameter assists practitioners in providing safe and appropriate SBRT treatment and care for patients when clinically indicated. As technologies and techniques continue to evolve, this document will be reviewed, revised and renewed accordingly to a 5 year or sooner timeline specified by the ACR.

42 sitasi en Medicine
arXiv Open Access 2021
To H0 or not to H0?

George Efstathiou

This paper investigates whether changes to late time physics can resolve the `Hubble tension'. It is argued that many of the claims in the literature favouring such solutions are caused by a misunderstanding of how distance ladder measurements actually work and, in particular, by the inappropriate use of a distance ladder H0 prior. A dynamics-free inverse distance ladder shows that changes to late time physics are strongly constrained observationally and cannot resolve the discrepancy between the SH0ES data and the base LCDM cosmology inferred from Planck. We propose a statistically rigorous scheme to replace the use of H0 priors

en astro-ph.CO

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