337 citations · 1.6k across the 31 of their papers we have counts for
31 papers
Search for quantum black hole production in lepton+jet final states using proton-proton collisions at = 13 TeV with the ATLAS detector
ATLAS Collaboration
A search for quantum black holes in electron+jet and muon+jet invariant mass spectra is performed with 140 fb of data collected by the ATLAS detector in proton-proton collis…
Dark Matter spikes around Sgr A* in -rays
Shyam Balaji, Divya Sachdeva, Filippo Sala +1
We use H.E.S.S. -ray observations of Sgr A* to derive novel limits on the Dark Matter (DM) annihilation cross-section. We quantify their dependence on uncertainties i) in the DM…
Planck Constraints and Gravitational Wave Forecasts for Primordial Black Hole Dark Matter Seeded by Multifield Inflation
Wenzer Qin, Sarah R. Geller, Shyam Balaji +2
We perform a Markov Chain Monte Carlo (MCMC) analysis of a simple yet generic multifield inflation model characterized by two scalar fields coupled to each other and nonminimally c…
Light scalar explanation for 18 TeV GRB 221009A
Shyam Balaji, Maura E. Ramirez-Quezada, Joseph Silk +1
Recent astrophysical transient Swift J1913.1+1946 may be associated with the -ray burst GRB 221009A. The redshift of this event is . Very high-energy -rays (up…
γ-Ray and ultra-high energy neutrino background suppression due to solar radiation
Shyam Balaji
The Sun emits copious amounts of photons and neutrinos in an approximately spatially isotropic distribution. Diffuse -rays and ultra-high energy (UHE) neutrinos from extragalact…
Improved stellar limits on a light CP-even scalar
Shyam Balaji, P. S. Bhupal Dev, Joseph Silk +1
We derive improved stellar luminosity limits on a generic light CP-even scalar field mixing with the Standard Model (SM) Higgs boson from the supernova SN1987A, the Sun, red gi…
Cosmological parameters from Planck data in SU(2), their local CDM values, and the modified photon Boltzmann equation
Ralf Hofmann, Janning Meinert, Shyam Sunder Balaji
A review of the spatially flat cosmological model SU(2), minimally induced by the postulate that the Cosmic Microwave Background (CMB) is subject to an SU(2) rather tha…
Observing nulling of primordial correlations via the 21 cm signal
Shyam Balaji, H. V. Ragavendra, Shiv K. Sethi +2
The 21cm line emitted by neutral hydrogen (HI) during the Dark Ages carries imprints of pristine primordial correlations. In models of inflation driven by a single, canonical scala…
Induced gravitational waves from slow-roll inflation after an enhancing phase
Shyam Balaji, Guillem Domenech, Joseph Silk
The primordial spectrum of fluctuations may present a large peak as a result of enhancing features during inflation. This may include, but is not limited to, bumps in the inflaton'…
Radio sky reveals primordial electron-proton interactions
Shyam Balaji, Maura E. Ramirez-Quezada, Celine Boehm
For several decades, astronomers have measured the electromagnetic emission in the universe from the lowest to the highest energies with incredible precision. The lowest end of the…
Induced gravitational waves from the cosmic coincidence
Shyam Balaji, Joseph Silk, Yi-Peng Wu
The induced gravitational wave (GW) background from enhanced primordial scalar perturbations is one of the most promising observational consequences of primordial black hole (PBH)…
Asymmetry in flavour changing electromagnetic transitions of vector-like quarks
Shyam Balaji
Vector-like quarks have been of interest for a plethora of experimentally motivated reasons and have come under increased investigation recently due to their inclusion to the Stand…
A search for the decays of stopped long-lived particles at TeV with the ATLAS detector
ATLAS Collaboration
A search for long-lived particles, which have come to rest within the ATLAS detector, is presented. The subsequent decays of these long-lived particles can produce high-momentum je…
Search for Higgs boson production in association with a high-energy photon via vector-boson fusion with decay into bottom quark pairs at =13 TeV with the ATLAS detector
ATLAS Collaboration
A search is presented for the production of the Standard Model Higgs boson in association with a high-energy photon. With a focus on the vector-boson fusion process and the dominan…
Cosmological bubble friction in local equilibrium
Shyam Balaji, Michael Spannowsky, Carlos Tamarit
In first-order cosmological phase transitions, the asymptotic velocity of expanding bubbles is of crucial relevance for predicting observables like the spectrum of stochastic gravi…
asymmetries in the rare top decays and
Shyam Balaji
The rare radiative flavour changing top decays and (and the even rarer and ) have been processes of interest for decades as they offer a key…
CP violation in neutral lepton transition dipole moment
Shyam Balaji, Maura Ramirez-Quezada, Ye-Ling Zhou
The violation in the neutrino transition electromagnetic dipole moment is discussed in the context of the Standard Model with an arbitrary number of right-handed singlet neutr…
Properties of Higgs Boson Interactions with Top Quarks in the and Processes Using with the ATLAS Detector
ATLAS Collaboration
A study of the properties of the interaction between the Higgs boson and top quarks is presented. Higgs bosons are identified via the diphoton decay channel ($H \rightarrow γγ…
Unified SU(4) theory for the and anomalies
Shyam Balaji, Michael A. Schmidt
We propose a chiral Pati-Salam theory based on the gauge group . The left-handed quarks and leptons are unified into a fundamental representati…
ATLAS data quality operations and performance for 2015-2018 data-taking
ATLAS Collaboration
The ATLAS detector at the Large Hadron Collider reads out particle collision data from over 100 million electronic channels at a rate of approximately kHz, with a recording r…
CP violation and circular polarisation in neutrino radiative decay
Shyam Balaji, Maura Ramirez-Quezada, Ye-Ling Zhou
The radiative decay of neutral fermions has been studied for decades but violation induced within such a paradigm has evaded attention. violation in these processes can p…
Combination of searches for invisible Higgs boson decays with the ATLAS experiment
ATLAS Collaboration
Dark matter particles, if sufficiently light, may be produced in decays of the Higgs boson. This Letter presents a statistical combination of searches for …
Measurement of the four-lepton invariant mass spectrum in 13 TeV proton-proton collisions with the ATLAS detector
ATLAS Collaboration
A measurement of the four-lepton invariant mass spectrum is made with the ATLAS detector, using an integrated luminosity of 36.1 fb of proton-proton collisions at …
More stringent constraints on the unitarised fermionic dark matter Higgs portal
Shyam Balaji, Archil Kobakhidze
We revisit the simplest model of Higgs portal fermionic dark matter. The dark matter in this scenario is thermally produced in the early universe due to the interactions with the H…