arXiv subjects

Sukanya Sinha

Publications and source records attributed to Sukanya Sinha.

16 recordsLinked to original sources

arXiv2026

AgentRivet: an automated system for producing Rivet routines from journal publications

Particle physics collider experiments provide Rivet routines as part of the analysis preservation strategy for model-independent measurements. Rivet is a C++ toolkit that allow new theoretical models to be compared to the measurements, thus aiding the development and tuning of Monte Carlo event generators as well as searches for physics beyond the Standard Model. However, analysis coverage is known to be incomplete, with only 39% of measurements having documented and publicly available Rivet routines. In this article, we design and implement an automated workflow based on Large Language Models with the goal of providing the missing routines. This multi-step workflow, referred to as AgentRivet, extracts the physics analysis information from published papers and writes the missing Rivet routines, with intermediate code- and physics- reviews as part of an autonomous quality control. We report the results obtained using commercial Large Language Models, provided by OpenAI, Anthropic, and Google, for two recent measurements from the ATLAS and CMS experiments. We find that AgentRivet produces competent Rivet routines with few syntax errors. The physics fidelity of the routines is reasonable and follows the explanations given in the relevant publications. Nevertheless, physics-implementation issues do arise and are investigated using the artefacts produced by AgentRivet. The majority of physics implementation issues arise from subtle-but-ambiguous definitions in the given publication, although some models struggle to implement complex observables even when clear definitions are given.

hep-ex↗

arXiv2026

Semi-visible Jets from Sneaky Dark Matter

In this paper, we compare two different ways of generating semi-visible jet signature in non-resonant production mode, and flag the potential advantages of the new generation approach we propose. In addition, we suggest a more efficient matrix element to parton shower matching configuration for this hadronic final state signature. Finally, we perform a reinterpretation study of the ATLAS search for t-channel semi-visible jet production and obtain collider limits on the sneaky DM scenario.

hep-ph↗

arXiv2026

Overview of the ESCAPE Dark Matter Test Science Project for Astronomers

The search for dark matter has been ongoing for decades within both astrophysics and particle physics. Both fields have employed different approaches and conceived a variety of methods for constraining the properties of dark matter, but have done so in relative isolation of one another. From an astronomer's perspective, it can be challenging to interpret the results of dark matter particle physics experiments and how these results apply to astrophysical scales. Over the past few years, the ESCAPE Dark Matter Test Science Project has been developing tools to aid the particle physics community in constraining dark matter properties; however, ESCAPE itself also aims to foster collaborations between research disciplines. This is especially important in the search for dark matter, as while particle physics is concerned with detecting the particles themselves, all of the evidence for its existence lies solely within astrophysics and cosmology. Here, we present a short review of the progress made by the Dark Matter Test Science Project and their applications to existing experiments, with a view towards how this project can foster complementary with astrophysical observations.

astro-ph.CO↗

arXiv2025

t-channel dark matter at the LHC -- a whitepaper

This report, summarising work achieved in the context of the LHC Dark Matter Working Group, investigates the phenomenology of $t$-channel dark matter models, spanning minimal setups with a single dark matter candidate and mediator to more complex constructions closer to UV-complete models. For each considered class of models, we examine collider, cosmological and astrophysical implications. In addition, we explore scenarios with either promptly decaying or long-lived particles, as well as featuring diverse dark matter production mechanisms in the early universe. By providing a unified analysis framework, numerical tools and guidelines, this work aims to support future experimental and theoretical efforts in exploring $t$-channel dark matter models at colliders and in cosmology.

hep-ph↗

arXiv2025

Probing the sensitivity of semi-visible jets to current LHC measurements using the CONTUR toolkit

Semi-visible jets arise from a hypothetical, strongly interacting ``dark sector'' -- a dark counterpart of quantum chromodynamics whose partial decays back to Standard Model particles introduce new types of collider BSM signature. CMS and ATLAS have have searched for semi-visible jets in the resonant and non-resonant production modes and set constraints on mediator mass values. In this work, indirect constraints on various model parameters, such as dark hadron masses and coupling strengths, are explored using LHC measurements.

hep-ph↗

arXiv2024

2B or not 2B, a study of bottom-quark-philic semi-visible jets

Semi-visible jets arise in strongly interacting dark sector, resulting in jets overlapping with the missing transverse momentum direction. The implementation of semi-visible jets is done using the Pythia Hidden Valley module to mimic the QCD sector showering in so-called dark shower. In this work, only heavy flavour Standard Model quarks are considered in dark shower, resulting in a much less ambiguous collider signature of semi-visible jets compared to the democratic production of all five quark flavours in dark shower. The constraints from available searches on this signature are presented, and it is shown the signal reconstruction can be improved by using variable-radius jets. Finally a search strategy is suggested.

hep-ph↗

arXiv2023

MITP Colours in Darkness workshop summary report

This report summarises the talks and discussions that took place over the course of the MITP Youngst@rs Colours in Darkness workshop 2023. All talks can be found at https://indico.mitp.uni-mainz.de/event/377/.

hep-ph↗

arXiv2022

Towards better discrimination and improved modelling of dark-sector showers

As no evidence for classic WIMP-based signatures of dark matter have been found at the LHC, several phenomenological studies have raised the possibility of accessing a strongly-interacting dark sector through new collider-event topologies. If dark mesons exist, their evolution and hadronization procedure are currently little constrained. They could decay promptly and result in QCD-like jet structures, even though the original decaying particles are dark sector ones; they could behave as semi-visible jets; or they could behave as completely detector-stable hadrons, in which case the final state is just the missing transverse momentum. In this contribution we will introduce a study performed to explore use of jet substructure methods to distinguish dark-sector from QCD jets in the first two scenarios, using observables in a IRC-safe linear basis, and discuss ways forward for this approach to dark-matter at the LHC.

hep-ph↗

arXiv2022

Theory, phenomenology, and experimental avenues for dark showers: a Snowmass 2021 report

In this work, we consider the case of a strongly coupled dark/hidden sector, which extends the Standard Model (SM) by adding an additional non-Abelian gauge group. These extensions generally contain matter fields, much like the SM quarks, and gauge fields similar to the SM gluons. We focus on the exploration of such sectors where the dark particles are produced at the LHC through a portal and undergo rapid hadronization within the dark sector before decaying back, at least in part and potentially with sizeable lifetimes, to SM particles, giving a range of possibly spectacular signatures such as emerging or semi-visible jets. Other, non-QCD-like scenarios leading to soft unclustered energy patterns or glueballs are also discussed. After a review of the theory, existing benchmarks and constraints, this work addresses how to build consistent benchmarks from the underlying physical parameters and present new developments for the PYTHIA Hidden Valley module, along with jet substructure studies. Finally, a series of improved search strategies is presented in order to pave the way for a better exploration of the dark showers at the LHC.

hep-ph↗

arXiv2021

Exploring Jet Substructure in Semi-visible jets

Semi-visible jets arise in strongly interacting dark sectors, where parton evolution includes dark sector emissions, resulting in jets overlapping with missing transverse momentum. The implementation of semi-visible jets is done using the Pythia Hidden valley module to duplicate the QCD sector showering. In this work, several jet substructure observables have been examined to compare semi-visible jets and light quark/gluon jets. These comparisons were performed using different dark hadron fraction in the semi-visible jets (signal). The extreme scenarios where signal consists either of entirely dark hadrons or visible hadrons offers a chance to understand the effect of the specific dark shower model employed in these comparisons. We attempt to decouple the behaviour of jet-substructure observables due to inherent semi-visible jet properties, from model dependence owing to the existence of only one dark shower model as mentioned above.

hep-ph↗

arXiv2003

Quantum Noise and Fluctuations in Gravitation and Cosmology

We give a short update of our research program on nonequilibrium statistical field theory applied to quantum processes in the early universe and black holes, as well as the development of stochastic gravity theory as an extension of semiclassical gravity and an intermediary in the 'bottom-up' approach to quantum gravity.

gr-qc↗

arXiv2002

Black Hole Fluctuations and Backreaction in Stochastic Gravity

We present a framework for analyzing black hole backreaction from the point of view of quantum open systems using influence functional formalism. We focus on the model of a black hole described by a radially perturbed quasi-static metric and Hawking radiation by a conformally coupled massless quantum scalar field. It is shown that the closed-time-path (CTP) effective action yields a non-local dissipation term as well as a stochastic noise term in the equation of motion, the Einstein-Langevin equation. Once the thermal Green's function in a Schwarzschild background becomes available to the required accuracy the strategy described here can be applied to obtain concrete results on backreaction. We also present an alternative derivation of the CTP effective action in terms of the Bogolyubov coefficients, thus making a connection with the interpretation of the noise term as measuring the difference in particle production in alternative histories.

gr-qc↗

arXiv1999

Notes on Black Hole Fluctuations and Backreaction

In these notes we prepare the ground for a systematic investigation into the issues of black hole fluctuations and backreaction by discussing the formulation of the problem, commenting on possible advantages and shortcomings of existing works, and introducing our own approach via a stochastic semiclassical theory of gravity based on the Einstein-Langevin equation and the fluctuation-dissipation relation for a self-consistent description of metric fluctuations and dissipative dynamics of the black hole with backreaction of its Hawking radiance.

gr-qc↗

arXiv1994

A Fluctuation-Dissipation Relation for Semiclassical Cosmology

Using the concept of open systems where the classical geometry is treated as the system and the quantum matter field as the environment, we derive a fluctuation-dissipation theorem for semiclassical cosmology. This theorem which exists under very general conditions for dissipations in the dynamics of the system, and the noise and fluctuations in the environment, can be traced to the formal mathematical relation between the dissipation and noise kernels of the influence functional depicting the open system, and is ultimately a consequence of the unitarity of the closed system. In particular, for semiclassical gravity, it embodies the backreaction effect of matter fields on the dynamics of spacetime. The backreaction equation derivable from the influence action is in the form of a Einstein-Langevin equation. It contains a dissipative term in the equation of motion for the dynamics of spacetime and a noise term related to the fluctuations of particle creation in the matter field. Using the well-studied model of a quantum scalar field in a Bianchi Type-I universe we illustrate how this Langevin equation and the noise term are derived and show how the creation of particles and the dissipation of anisotropy during the expansion of the universe can be understood as a manifestation of this fluctuation-dissipation relation.

gr-qc↗

arXiv1993

Minisuperspace as a Quantum Open System

We trace the development of ideas on dissipative processes in chaotic cosmology and on minisuperspace quantum cosmology from the time Misner proposed them to current research. We show 1) how the effect of quantum processes like particle creation in the early universe can address the issues of the isotropy and homogeneity of the observed universe, 2) how viewing minisuperspace as a quantum open system can address the issue of the validity of such approximations customarily adopted in quantum cosmology, and 3) how invoking statistical processes like decoherence and correlation when considered together can help to establish a theory of quantum fields in curved spacetime as the semiclassical limit of quantum gravity. {\it Dedicated to Professor Misner on the occasion of his sixtieth birthday, June 1992.} To appear in the Proceedings of a Symposium on {\it Directions in General Relativity}, College Park, May 1993, Volume 1, edited by B. L. Hu, M. P. Ryan and C. V. Vishveshwara (Cambridge University Press 1993)~~~~umdpp 93-60

gr-qc↗

arXiv1992

A Nonlinear Model of a Quantum Minisuperspace System with Back Reaction

We consider the quantum evolution of the space-independent mode of a $λϕ^4$ theory as a minisuperspace in the space of all $ϕ$. The motion of the wave packet in the minisuperspace is then compared to the motion of a wave packet in a larger minisuperspace consisting of the original minisuperspace plus one space-dependent mode. By comparing the motion of the two packets we develop criteria that tell us when the quantum evolution in the space-independent minisuperspace gives us useful information about the true evolution in the larger minisuperspace. These criteria serve as a toy model for similar(but much more complex) criteria that will tell us whether or when quantized gravitational minisuperspaces can possibly give any useful information about quantum gravity.

gr-qc↗