arXiv subjects

Ruchi Gupta

Publications and source records attributed to Ruchi Gupta.

8 recordsLinked to original sources

arXiv2021

Constraining off-shell production of axion-like particles with $Z\gamma$ and $WW$ differential cross-section measurements

This article describes a search for low-mass axion-like particles (ALPs) at the Large Hadron Collider (LHC). If ALPs were produced at the LHC via gluon-gluon fusion and decayed to bosons, the energy dependence of the measured diboson cross-sections would differ from the Standard Model expectation. Measurements of $WW$ and $Z\gamma$ differential cross-sections by the ATLAS collaboration are interpreted to constrain ALP couplings to $W$-, $Z$-bosons and photons assuming gluon-gluon-fusion production.

hep-ex↗

arXiv2020

The ABC130 barrel module prototyping programme for the ATLAS strip tracker

For the Phase-II Upgrade of the ATLAS Detector, its Inner Detector, consisting of silicon pixel, silicon strip and transition radiation sub-detectors, will be replaced with an all new 100 % silicon tracker, composed of a pixel tracker at inner radii and a strip tracker at outer radii. The future ATLAS strip tracker will include 11,000 silicon sensor modules in the central region (barrel) and 7,000 modules in the forward region (end-caps), which are foreseen to be constructed over a period of 3.5 years. The construction of each module consists of a series of assembly and quality control steps, which were engineered to be identical for all production sites. In order to develop the tooling and procedures for assembly and testing of these modules, two series of major prototyping programs were conducted: an early program using readout chips designed using a 250 nm fabrication process (ABCN-25) and a subsequent program using a follow-up chip set made using 130 nm processing (ABC130 and HCC130 chips). This second generation of readout chips was used for an extensive prototyping program that produced around 100 barrel-type modules and contributed significantly to the development of the final module layout. This paper gives an overview of the components used in ABC130 barrel modules, their assembly procedure and findings resulting from their tests.

physics.ins-det↗

arXiv2016

Parton level study of high ET jets in hard QCD processes at LHC

Inclusive jet production will dominate the high $Q^{2}$ final states at the LHC.~In this work we try to estimate the up-to-date expectations, for high $E_{T}$ jets and their expected origin from the various parton-parton scattering processes. For these studies we have used a standard Parton Distribution Function (PDF) and simulated millions of events with the PYTHIA8 event genertor. The results are compared with simulations for center-of-mass energies of 0.9 TeV, 2.36 TeV, 7 TeV and 14 TeV corresponding to existing and future LHC runs. We present some expectations for the relative cross sections of different quark flavours which indicates that eventually we might be able to measure the cross section for b-flavoured jets with reasonable accuracy up to an $E_T$ of a few TeV.

hep-ph↗

arXiv2009

Zero-spin-photon hypothesis: `Zero-spin-photon generation in pair-production and its subsequent decay into neutrino and antineutrino' - solves many-riddles of physics and universe

`What is work and what is heat' is re-investigated from the perspective of second law of thermodynamics. It is shown that the inevitable consequence of second law of thermodynamics and spin conservation necessitates the possible generation of zero spin photon in pair production process, and its subsequent decay explains the birth of neutrino and antineutrino. The proposed neutrino-genesis, solves many riddles of physics and universe. The riddles considered and explained are about: (i) mysterious neutrino (and antineutrino) and its bizarre properties such as handed-ness and parity-violation, (ii) questionable asymmetry/ excess of matter over antimatter, (iii) possibility of existence of antimatter world and (iv) parity (P) violation and aspects of CP and CPT violation or restoration in the universe.

physics.gen-ph↗

arXiv2005

On Possibility of Using High-Tc Ceramic-Superconductor as Junction-less Transistor towards Nano-miniaturization

High-Tc Type-II ceramic-superconductor at temperature T < Tc, under presence of magnetic-field B becomes non-superconducting if B exceeds a critical value Bc2. Thus at T < Tc, by application/absence of critical magnetic- field as a controlling device, these non-superconducting/superconductor states can be achieved for current-flow to two corresponding states of block/pass or off/on or 0/1. Thus it appears that there is a possibility of a new breed of transistors purely with high-Tc Type-II ceramic-superconductor; compact and without junctions & complexities. The proposed ceramic-superconductor-transistor (CST) seems in-principle to work well for switching purpose, but its use could also be extended for other electronic/computer devices too. The CST, being junction-less thus diffusion-less, could possibly be packed more closely (at nano-level) than the semi-conductor devices which has a limitation due to diffusion-layer-overlapping. A similar superconductor-device named Cryotron was invented at MIT half-a-century ago, but could not survive against semiconductor. CST is a rebirth of cryotron in different disguise & in new perspective.

physics.gen-ph↗

arXiv2005

A Novel General Theoretical Derivation of Newton-Experimental-Formula for Collision of Particles

An experimental formula, sometimes named as Newton-collision-formula, (v1-v2) = - e.(u1-u2) relating relative-velocities before & after impact of two bodies under linear-collision, is commonly used successfully for study of collision-dynamics. Although it seems possible as shown in text-books [1,2] to derive this relation, assuming (defining) e as ratio of impulses during restitution & deformation; but as yet, neither a good theoretical-basis nor a general-derivation of this formula based on obvious choice of energy-consideration, has been reported. In this brief-paper a relativistic-theoretical-basis is adopted and a general formula-derivation is given. It is shown, interestingly, that proof of the Newton-collision-formula is hidden in Einstein-special-relativity.

physics.gen-ph↗

arXiv2003

Is Second Law of Thermodynamics Violated for Electron Transition from Lower-Energy Level to Higher-Energy Level

Second law of thermodynamics is applied to a few electronic processes. It is seen that the second law of thermodynamics holds good for all except one mentioned here. The classical approach, based on exact equivalence of emission and absorption spectra, for electron transition from lower energy level (first orbit) to higher energy level (second orbit) violates the second law of thermodynamics. But since second law which implies irreversibility and is universally true, a new explanation of electron transition from lower to higher energy level is proposed which leads to better understanding of several topics such as Fraunhofer lines, Optical laser. Also, interestingly, it is shown that widely different fields such as second law of thermodynamics and special relativity are in fact closely linked to each other. Also, possible links between supersymmetry and new concept of quaternion mass are mentioned.

physics.gen-ph↗

arXiv2003

Predicting Response-Function Results of Electrical/Mechanical Systems Through Artificial Neural Network

In the present paper a newer application of Artificial Neural Network (ANN) has been developed i.e., predicting response-function results of electrical-mechanical system through ANN. This method is specially useful to complex systems for which it is not possible to find the response-function because of complexity of the system. The proposed approach suggests that how even without knowing the response-function, the response-function results can be predicted with the use of ANN to the system. The steps used are: (i) Depending on the system, the ANN-architecture and the input & output parameters are decided, (ii) Training & test data are generated from simplified circuits and through tactic-superposition of it for complex circuits, (iii) Training the ANN with training data through many cycles and (iv) Test-data are used for predicting the response-function results. It is found that the proposed novel method for response prediction works satisfactorily. Thus this method could be used specially for complex systems where other methods are unable to tackle it. In this paper the application of ANN is particularly demonstrated to electrical-circuit system but can be applied to other systems too.

cs.NE↗