Search for the Higgs Boson at the ATLAS Experiment
Lead Research Organisation:
University of Warwick
Department Name: Physics
Abstract
Over a century of study has led physicists to develop the Standard Model theory (SM) of the building blocks of matter and the forces among them. This combines the strong force which binds quarks into nuclei, the weak force which explains radioactivity and the electromagnetic force which holds electrons in atoms. To date, it is the most accurately tested scientific theory, verified to a few parts per billion! Given this amazing success you may wonder why scientists have any doubts about the theory. However, one piece is missing: understanding the generation of mass. Despite all of the SM's testable predictions, it cannot predict any particle's mass (and by extension cannot explain your or my weight). This challenge inspires theories ranging from tweaks of the SM, to more outlandish, but possibly true, theories which require a plethora of new particles, possibly accounting for dark matter. In 1964 Peter Higgs, now Edinburgh professor emeritus, proposed an elegant solution to the mass generation problem requiring only one new particle. This 'boson' grabs hold of other particles and the stronger it holds on, the heavier they become. The eponymous Higgs boson has been a holy grail of fundamental science ever since. Although the Higgs boson was devised to generate mass, its own mass is unspecified. Scientists worldwide have searched for it unsuccessfully, ruling out large mass ranges and driving the search to increasingly high energies. Evidence from other precision data now predicts that if the SM Higgs boson exists, it can be found at the Large Hadron Collider (LHC) at the European Centre for Particle Physics (CERN) which will collide protons in a 27km underground ring at unprecedented energies in 2008. There, we should find the long-awaited SM Higgs boson or, possibly, a boson with unexpected properties revealing that more complex dynamics occur in nature, prompting an entire re-think or extension of the SM. If it exists, my proposed programme will discover the SM Higgs boson in the experimentally favoured low mass range. If not, I may find nature's Higgs surrogate. My careful study will identify which of these scenarios is realised. I will search data from the ATLAS experiment at LHC, analysing 10 billion catalogued collisions, a task likened to finding one phone number in a 1000 directories. However, this is no random search since we know how to look for this 'number': we can do the equivalent of finding out the person's surname by looking for known characteristics of the Higgs boson in data! Theoretical understanding of the boson and experimental skill will pinpoint it in the midst of the maelstrom of activity in energetic proton collisions. I will build and lead a team in the Oxford ATLAS group to find the Higgs boson in its decay to two tau leptons or bottom quarks. With careful analysis of the data, these will provide distinctive experimental fingerprints. Simulations show that these decays will yield the five statistical standard deviations 'gold standard' of convincing discovery. The combination of the group's expertise and my in-depth experience from the USA's Tevatron collider will provide a firm foundation for each member of the team to study one element of the signature. For example by homing in on datasets which contain signatures of known particles which decay like the Higgs boson, the identification algorithms can be honed. Finding the tau lepton or bottom quark requires algorithms which I will base on my experience of precision measurements in the bottom quark sector. These studies will characterise the ATLAS hardware enabling us to search the phonebooks of nature which the experiment provides. We cannot be sure that the Standard Model Higgs boson exists, but we can be certain that the hunt for the Higgs will be a fascinating journey whose destination may prove Peter Higgs right, or even more excitingly, that nature is richer and more complex than he imagined.
People |
ORCID iD |
Sinead Farrington (Principal Investigator / Fellow) |
Publications
Collaboration T
(2008)
The ATLAS Experiment at the CERN Large Hadron Collider
in Journal of Instrumentation
Aad G
(2010)
Readiness of the ATLAS liquid argon calorimeter for LHC collisions
in The European Physical Journal C
Aad G
(2010)
Observation of a Centrality-Dependent Dijet Asymmetry in Lead-Lead Collisions at s NN = 2.76 TeV with the ATLAS Detector at the LHC
in Physical Review Letters
Aad G
(2010)
The ATLAS Simulation Infrastructure
in The European Physical Journal C
Aad G
(2010)
Performance of the ATLAS detector using first collision data
in Journal of High Energy Physics
Aad G
(2010)
Readiness of the ATLAS Tile Calorimeter for LHC collisions
in The European Physical Journal C
Aad G
(2010)
Search for New Particles in Two-Jet Final States in 7 TeV Proton-Proton Collisions with the ATLAS Detector at the LHC
in Physical Review Letters
Aad G
(2010)
Drift Time Measurement in the ATLAS Liquid Argon Electromagnetic Calorimeter using Cosmic Muons
in The European Physical Journal C
Aad G
(2010)
Charged-particle multiplicities in pp interactions at s = 900 GeV measured with the ATLAS detector at the LHC
in Physics Letters B
Aad G
(2010)
The ATLAS Inner Detector commissioning and calibration
in The European Physical Journal C
Aad G
(2010)
Commissioning of the ATLAS Muon Spectrometer with cosmic rays
in The European Physical Journal C
Aad G
(2011)
Search for neutral MSSM Higgs bosons decaying to t + t - pairs in proton-proton collisions at s = 7 TeV with the ATLAS detector
in Physics Letters B
Aad G
(2011)
Charged-particle multiplicities in pp interactions measured with the ATLAS detector at the LHC
in New Journal of Physics
Aaltonen T
(2011)
Improved determination of the sample composition of dimuon events produced in $p\bar{p}$ collisions at $\sqrt{s}=1.96$ TeV
in The European Physical Journal C
Aaltonen T
(2011)
Measurement of the top-quark mass in the lepton+jets channel using a matrix element technique with the CDF II detector
in Physical Review D
Aad G
(2011)
A search for new physics in dijet mass and angular distributions in pp collisions at \sqrt{s}=7 TeV measured with the ATLAS detector
in New Journal of Physics
Aad G
(2011)
Measurement of Dijet Azimuthal Decorrelations in p p Collisions at s = 7 TeV
in Physical Review Letters
Aaltonen T
(2011)
Search for B(s)(0) ? µ+ µ- and B(0) ? µ+ µ- decays with CDF II.
in Physical review letters
Aad G
(2011)
Search for Diphoton Events with Large Missing Transverse Energy in 7 TeV Proton-Proton Collisions with the ATLAS Detector
in Physical Review Letters
Aaltonen T
(2011)
Top-quark mass measurement using events with missing transverse energy and jets at CDF.
in Physical review letters
Aad G
(2011)
Search for a Standard Model Higgs Boson in the H ? Z Z ? l + l - ? ? ¯ Decay Channel with the ATLAS Detector
in Physical Review Letters
Aad G
(2011)
Search for high mass dilepton resonances in pp collisions at s = 7 TeV with the ATLAS experiment
in Physics Letters B
Aad G
(2011)
Measurement of the W charge asymmetry in the W ? µ ? decay mode in pp collisions at s = 7 TeV with the ATLAS detector
in Physics Letters B
Aad G
(2011)
Measurement of inclusive jet and dijet cross sections in proton-proton collisions at 7 TeV centre-of-mass energy with the ATLAS detector
in The European Physical Journal C
Aad G
(2011)
Search for dilepton resonances in pp collisions at vs=7 TeV with the ATLAS detector.
in Physical review letters
Aad G
(2011)
Studies of the performance of the ATLAS detector using cosmic-ray muons
in The European Physical Journal C
Aaltonen T
(2011)
Measurement of the cross section for prompt isolated diphoton production in p p ¯ collisions at s = 1.96 TeV
in Physical Review D
Aad G
(2011)
Measurement of W? and Z? production in proton-proton collisions at $ \sqrt {s} = 7 $ TeV with the ATLAS detector
in Journal of High Energy Physics
Aad G
(2011)
Search for heavy long-lived charged particles with the ATLAS detector in pp collisions at s = 7 TeV
in Physics Letters B
Aad G
(2011)
Search for new phenomena in final states with large jet multiplicities and missing transverse momentum using $\sqrt {s}$ = 7 TeV pp collisions with the ATLAS detector
in Journal of High Energy Physics
Aaltonen T
(2011)
Measurement of the t t ¯ production cross section in p p ¯ collisions at s = 1.96 TeV using events with large missing transverse energy and jets
in Physical Review D
Aaltonen T
(2011)
Observation of the ?(b)(0) baryon.
in Physical review letters
Aad G
(2011)
Search for supersymmetric particles in events with lepton pairs and large missing transverse momentum in $\sqrt{s}=7~\mbox{TeV}$ proton-proton collisions with the ATLAS experiment
in The European Physical Journal C
Aaltonen T
(2011)
Search for new dielectron resonances and Randall-Sundrum gravitons at the collider detector at Fermilab.
in Physical review letters
Aad G
(2011)
Measurement of the W + W - Cross Section in s = 7 TeV p p Collisions with ATLAS
in Physical Review Letters
Aad G
(2011)
Measurement of multi-jet cross sections in proton-proton collisions at a 7 TeV center-of-mass energy
in The European Physical Journal C
Aaltonen T
(2011)
First search for multijet resonances in sqrt(s) = 1.96 TeV pp collisions.
in Physical review letters
Aad G
(2011)
Search for supersymmetry in pp collisions at s = 7 TeV in final states with missing transverse momentum and b-jets
in Physics Letters B
Aad G
(2011)
Study of jet shapes in inclusive jet production in p p collisions at s = 7 TeV using the ATLAS detector
in Physical Review D
Aad G
(2011)
Properties of jets measured from tracks in proton-proton collisions at center-of-mass energy s = 7 TeV with the ATLAS detector
in Physical Review D
Aaltonen T
(2011)
Measurement of branching ratio and B s 0 lifetime in the decay B s 0 ? J / ? f 0 ( 980 ) at CDF
in Physical Review D
Aad G
(2011)
Measurement of the inclusive isolated prompt photon cross-section in pp collisions at s = 7 TeV using 35 pb - 1 of ATLAS data
in Physics Letters B
Aad G
(2011)
Measurement of dijet production with a veto on additional central jet activity in pp collisions at $ \sqrt {s} = 7 $ TeV using the ATLAS detector
in Journal of High Energy Physics
Aad G
(2011)
Limits on the production of the standard model Higgs boson in pp collisions at $\sqrt{s} = 7$ TeV with the ATLAS detector
in The European Physical Journal C
Aaltonen T
(2011)
Search for a heavy toplike quark in pp collisions at vs=1.96 TeV.
in Physical review letters
Aaltonen T
(2011)
Measurement of the B(s)0 lifetime in fully and partially reconstructed B(s)0?D(s)(-)(?p(-))X decays in p¯p collisions at vs=1.96 TeV.
in Physical review letters
Description | Higgs boson searches for tau leptons yielded observation in 2015. |
Exploitation Route | Fundamental science understanding. |
Sectors | Other |