1 Models of New Physics with Dijets Robert M. Harris Fermilab HEP Group Talk at Texas Tech April 20, 2006.

Slides:



Advertisements
Similar presentations
Kiwoon Choi PQ-invariant multi-singlet NMSSM
Advertisements

Electroweak Symmetry Breaking from D-branes Joshua Erlich College of William & Mary Title U Oregon, May 22, 2007 w/ Chris Carone, Marc Sher, Jong Anly.
Extra Dimensions of Space-Time String theory suffers conformal anomaly that makes theory inconsistent --> get rid of it Conformal anomaly ~ (D-26) for.
Black Holes and Particle Species Gia Dvali CERN Theory Division and New York University.
HL-2 April 2004Kernfysica: quarks, nucleonen en kernen1 Outline lecture (HL-2) Quarkonium Charmonium spectrum quark-antiquark potential chromomagnetic.
The Standard Model and Beyond [Secs 17.1 Dunlap].
Hep-ph/ , with M. Carena (FNAL), E. Pontón (Columbia) and C. Wagner (ANL) New Ideas in Randall-Sundrum Models José Santiago Theory Group (FNAL)
The minimal B-L model naturally realized at TeV scale Yuta Orikasa(SOKENDAI) Satoshi Iso(KEK,SOKENDAI) Nobuchika Okada(University of Alabama) Phys.Lett.B676(2009)81.
Compelling Questions of High Energy Physics? What does the future hold? Persis S. Drell Physics Department Cornell University.
Higgs Boson Mass In Gauge-Mediated Supersymmetry Breaking Abdelhamid Albaid In collaboration with Prof. K. S. Babu Spring 2012 Physics Seminar Wichita.
ATLAS Experiment at CERN. Why Build ATLAS? Before the LHC there was LEP (large electron positron collider) the experiments at LEP had observed the W and.
The Elementary Particles Santa Rosa Junior College Physics 4D – Younes Ataiiyan May 11 th 2006 Stephen Ngamate and Thomas Mutunga.
Chiral freedom and the scale of weak interactions.
Richard Howl The Minimal Exceptional Supersymmetric Standard Model University of Southampton UK BSM 2007.
4 th Generation Leptons in Minimal Walking Technicolor Theory Matti Heikinheimo University of Jyväskylä.
1 Discovering New Physics with the LHC Nadia Davidson Supervisor: Elisabetta Barberio EPP Nobel Prize for Physics in 2010:
Smashing the Standard Model: Physics at the CERN LHC
P461 - particles I1 all fundamental with no underlying structure Leptons+quarks spin ½ while photon, W, Z, gluons spin 1 No QM theory for gravity Higher.
Chiral freedom and the scale of weak interactions.
30 August 04Lorenzo Feligioni1 Searches for Techniparticles at DØ Lorenzo Feligioni Boston University for the DØ collaboration.
CUSTODIAL SYMMETRY IN THE STANDARD MODEL AND BEYOND V. Pleitez Instituto de Física Teórica/UNESP Modern Trends in Field Theory João Pessoa ─ Setembro 2006.
The Ideas of Unified Theories of Physics Tareq Ahmed Mokhiemer PHYS441 Student.
Physics with ATLAS and CMS Are there new symmetries or extra-dimensions? What is dark matter? Where does mass come from? The two big multi-purpose experiments.
Chiral freedom and the scale of weak interactions.
.. Particle Physics at a Crossroads Meenakshi Narain Brown University.
Modern Physics LECTURE II.
 Collaboration with Prof. Sin Kyu Kang and Prof. We-Fu Chang arXiv: [hep-ph] submitted to JHEP.
Kaluza-Klein gluon production at the LHC
Option 212: UNIT 2 Elementary Particles Department of Physics and Astronomy SCHEDULE 26-Jan pm LRB Intro lecture 28-Jan pm LRBProblem solving.
Center for theoretical Physics at BUE
Joseph Haley Joseph Haley Overview Review of the Standard Model and the Higgs boson Creating Higgs bosons The discovery of a “Higgs-like” particle.
Sigma model and applications 1. The linear sigma model (& NJL model) 2. Chiral perturbation 3. Applications.
1 Introduction to Dijet Resonance Search Exercise John Paul Chou, Eva Halkiadakis, Robert Harris, Kalanand Mishra and Jason St. John CMS Data Analysis.
School of Arts & Sciences Dean’s Coffee Presentation SUNY Institute of Technology, February 4, 2005 High Energy Physics: An Overview of Objectives, Challenges.
Low scale gravity mediation in warped extra dimensions and collider phenomenology on sector hidden sector LCWS 06, March 10, Bangalore Nobuchika.
Hep-ph/ , with M. Carena (FNAL), E. Pontón (Columbia) and C. Wagner (ANL) Light KK modes in Custodially Symmetric Randall-Sundrum José Santiago Theory.
Heavy resonances in the top quark sector: from hadron colliders to the ILC Germán Rodrigo Beijing, March 2010.
Wednesday, Apr. 23, 2003PHYS 5326, Spring 2003 Jae Yu 1 PHYS 5326 – Lecture #24 Wednesday, Apr. 23, 2003 Dr. Jae Yu Issues with SM picture Introduction.
The Hierarchy Problem and New Dimensions at a Millimeter Ye Li Graduate Student UW - Madison.
1 Supersymmetry Yasuhiro Okada (KEK) January 14, 2005, at KEK.
Low scale supergravity mediation in brane world scenario and hidden sector phenomenology Phys.Rev.D74:055005,2006 ( arXiv: hep-ph/ ) ACFA07 in Beijing:
1 Probing New Physics with Dijets at CMS Robert M. Harris Fermilab HEP Seminar Johns Hopkins University March 26, 2008.
Electroweak Symmetry Breaking without Higgs Bosons in ATLAS Ryuichi Takashima Kyoto University of Education For the ATLAS Collaboration.
STANDARD MODEL class of “High Energy Physics Phenomenology” Mikhail Yurov Kyungpook National University November 15 th.
SUSY and Superstrings Masahiro Yamaguchi Tohoku University Asian School Particles, Strings and Cosmology (NasuLec) September 25-28, Japan.
Latest New Phenomena Results from Alexey Popov (IHEP, Protvino) For the DO Collaboration ITEP, Moscow
Compelling Scientific Questions The International Linear Collider will answer key questions about matter, energy, space and time We now sample some of.
The Search For Supersymmetry Liam Malone and Matthew French.
ELECTROWEAK UNIFICATION Ryan Clark, Cong Nguyen, Robert Kruse and Blake Watson PHYS-3313, Fall 2013 University of Texas Arlington December 2, 2013.
Standard Model - Standard Model prediction (postulated that neutrinos are massless, consistent with observation that individual lepton flavors seemed to.
03/31/2006S. M. Lietti - UED Search at SPRACE 1 Universal Extra Dimensions Search at SPRACE S. M. Lietti DOSAR Workshop at U.T. Arlington.
Constructing 5D Orbifold GUTs from Heterotic Strings w/ R.J. Zhang and T. Kobayashi Phys. Lett. B593, 262 (2004) & Nucl. Phys. B704, 3 (2005) w/ A. Wingerter.
1 New Physics with Dijets at CMS Selda Esen and Robert M. Harris Fermilab Kazim Gumus and Nural Akchurin Texas Tech Physics Colloquium at Texas Tech April.
Physics 222 UCSD/225b UCSB Lecture 12 Chapter 15: The Standard Model of EWK Interactions A large part of today’s lecture is review of what we have already.
10/29/2007Julia VelkovskaPHY 340a Lecture 4: Last time we talked about deep- inelastic scattering and the evidence of quarks Next time we will talk about.
Charge asymmetry: a theory appraisal Germán Rodrigo Brugge, May 31 - June 4, 2010.
1 Probing New Physics with Jets at the LHC Robert M. Harris Fermilab Los Alamos Seminar November 28, 2007.
Jim Olsen Princeton University Colloquium of the School of Physics and Astronomy Queen Mary University of London January 17, 2014 Nature of the New Boson:
A boost for a whole life M.V. Chizhov (Sofia University and JINR) Dedicated to the memory of my teacher Prof. Mateev.
1 Dijet Resonances Kazım Z. Gümüş and Nural Akchurin Texas Tech University Selda Esen and Robert M. Harris Fermilab PRS JETMET Meeting July 6, 2005.
Nick Evans University of Southampton
Abd Elrahman Ahmed Elsaid
From Last Time… Discussed the weak interaction
The symmetry of interactions
The MESSM The Minimal Exceptional Supersymmetric Standard Model
Search For New Physics Chary U of S.
From Last Time… Discussed the weak interaction
From Last Time… Discussed the weak interaction
Lecture 12 Chapter 15: The Standard Model of EWK Interactions
Presentation transcript:

1 Models of New Physics with Dijets Robert M. Harris Fermilab HEP Group Talk at Texas Tech April 20, 2006

Robert Harris, Fermilab2 Outline l Questions of the Standard Model l Dijet Resonances and Quark Contact Interactions l Models of New Physics with Dijets è Compositeness: Excited Quarks è Superstrings: E 6 diquarks è Extra SU(3): Axigluons and Colorons è Technicolor: Color Octet Technirhos è GUTS: W’ & Z’ è Extra Dimensions: Randall-Sundrum Gravitons l Model-less Motivation l Conclusions

Robert Harris, Fermilab3 Beyond the Standard Model l The Standard Model raises questions. l Why three nearly identical generations of quarks and leptons? è Like the periodic table of the elements, does this suggest an underlying physics? l What causes the flavor differences within a generation? è Or mass difference between generations? l How do we unify the forces ?  , Z and W are unified already. è Can we include gluons ? è Can we include gravity ? è Why is gravity so weak ? l These questions suggest there will be new physics beyond the standard model. è We will search for new physics with dijets. ? ? ?

Robert Harris, Fermilab4 Models of New Physics with Dijets l Two types of observations will be considered. è Dijet resonances are new particles beyond the standard model. è Quark contact Interactions are new interactions beyond the standard model. l Dijet resonances are found in models that try to address some of the big questions of particle physics beyond the SM, the Higgs, or Supersymmetry  Why Flavor ?  Technicolor or Topcolor  Octet Technirho or Coloron  Why Generations ?  Compositeness  Excited Quarks  Why So Many Forces ?  Grand Unified Theory  W’ & Z’  Can we include Gravity ?  Superstrings  E6 Diquarks  Why is Gravity Weak ?  Extra Dimensions  RS Gravitions l Quark contact interactions result from most new physics involving quarks. è Quark compositeness is the most commonly sought example.

Robert Harris, Fermilab5 Dijet Resonances l New particles that decay to dijets è Produced in “s-channel” è Parton - Parton Resonances à Observed as dijet resonances.  Many models have small width  à Similar dijet resonance shapes. X q, q, g Time Space Mass Rate Breit- Wigner  M 11 11 22 11 11 1+1+ ½+½ J P qq0.01SingletZ ‘Heavy Z q1q2q1q2 0.01SingletW ‘Heavy W qq,gg0.01SingletGR S Graviton qq,gg0.01Octet  T8 Octet Technirho qq0.05OctetCColoron qq0.05OctetAAxigluon qg0.02Tripletq*Excited Quark ud0.004TripletDE 6 Diquark Chan  / (2M) ColorXModel Name

Robert Harris, Fermilab6 Quark Contact Interactions New physics at large scale  è Composite Quarks è New Interactions l Modelled by contact interaction  Intermediate state collapses to a point for dijet mass << . l Observable Consequences è Has effects at high dijet mass. è Higher rate than standard model. è Angular distributions can be different from standard model. à This is true for the canonical model of a contact among left- handed quarks by Eichten, Lane and Peskin. Quark Contact Interaction  M ~  Composite QuarksNew Interactions M ~  Dijet Mass <<  q q q q q q q q

Robert Harris, Fermilab7 Compositeness: Excited Quarks Baur, Spira & Zerwas, PRD42,815(1990) l Motivation è Three nearly identical generations suggests compositeness. Periodic table ? è Compositeness is also historically motivated.  Matter  Molecules  Atoms  Nucleons  Quarks  Preons ? l If quarks are composite particles then excited states, q*, are expected è Excited quarks are produced when a ground state quark absorbs a gluon.  q* decay to the ground state q by emitting any gauge boson: , W, Z or g  The dijet process is qg  q*  qg, and cross section is large (color force). l J = 1/2 and J =3/2 are possible, but searches have been done for J = 1/2. è For example, imagine a non-relativistic model with two preons, one S=0, the other S=1/2, ground state L=0, excited state L=1, J=1/2. l Lagrangian is of magnetic moment type (see Review of Particle Physics)  Usually the couplings f, f s, f’ are set to 1, and  is set to q* mass M.

Robert Harris, Fermilab8 l Superstrings, supersymmetric string theories, claim to be a theory of everything è They unify gravity with other forces and claim all particles are string excitations. l They require 10 dimensions, 6 of which must be compactified (curled up). è One attractive compactification proposal leads to 27 fields in the fundamental representation of E 6. è This Grand Unified Theory breaks down via SO(10) and SU(5) to the Standard Model: SU(3) C x SU(2) L x U(1) Y. l Model has color triplet, charge ±1/3, scalar diquarks: D.  1 st generation production and decay: ud  D  ud. è Yukawa type Lagrangian with each generation: , is usually assumed to be an electromagnetic strength coupling: = e. è Cross section is large because u and d are valence quarks of proton. à Would be two orders of magnitude larger if color strength couplings were considered! Superstrings: E 6 Diquarks Angelopoulous, Ellis, Kowalski, Nanopoulos, Tracas & Zwirner

Robert Harris, Fermilab9 Extra SU(3): Axigluons and Colorons l Chiral Color was proposed by Frampton & Glashow è “We regard chiral color as a logical alternative to the standard model that is neither more nor less compelling”. è Fundamental gauge groups are SU(3) L x SU(3) R x SU(2) L x U(1) Y è Breaks down to SM plus color octet of massive axial-vector gluons: Axigluons. è Axigluons couple to quark anti-quark pairs with usual color strength. è LHC cross sections are large despite needing an anti-quark from the proton. l Colorons exist in many models. è Topcolor, Topcolor Extended Technicolor, and Flavor Universal Colorons è Last model by Chivukula, Cohens and Simmons is like Chiral Color “sans spin” è Gauge group simply has another SU(3): SU(3) 1 x SU(3) 2 x SU(2) L x U(1) Y è Breaks down to the SM plus a color octet of massive vector gluons: Colorons. è Colorons couple strongly to quark anti-quark pairs.  Cross sections are same as axigluons if the additional mixing angle cot 

Robert Harris, Fermilab10 Technicolor: Color Octet Technirhos (Ken Lane, hep-ph/ ) l Technicolor has been around a long time and is not dead. è Originally proposed as a model of dynamical electroweak symmetry breaking: à The Higgs boson is not a fundamental scalar. à Higgs is a technipion that is a bound state of two technifermions interacting via technicolor. à Theorists have analogies why this is better than a fundamental scalar. ð Cooper Pairs in Superconductivity, QCD naturally breaking symmetries, etc.  Minimal model has at least a single family of technifermions that bind to form color singlet  T,  T, and  T, etc.  One family model has both color triplet techniquarks and color singlet technileptons, and in this model there are color octet technirhos,  T8. l Extended Technicolor attempts to generate flavor dynamically è Quark & lepton masses come from emitting and absorbing ETC gauge bosons. è The model tries to address a difficult problem, but is far from complete. l Color Octet Technirhos are produced via mixing with gluons  Dijet production at LHC is q qbar, gg  g   T8  g  q qbar, gg. è Mixing reduces the size of cross section compared to other colored resonances

Robert Harris, Fermilab11 GUTS: W’ and Z’ l W’ is a heavy W boson è One model is the W R boson in left-right symmetric models. à Gauge group is SU(3) C x SU(2) L x SU(2) R X U(1) à Seeks to provide a spontaneous origin for parity violation in weak interactions. è Also a W’ in “alternative left-right model” in E 6 GUT. è We consider the Sequential Standard Model (SSM) W’ à W’ is same as W but more massive. à LHC cross section is same as W scaled by (M W /M W’ ) 2. Small. l Z’ boson is a heavy Z boson è These are common features of models of new physics. è GUTS frequently produce an extra U(1) symmetry when they break down to SM. à Each U(1) gives a new Z’ è We consider the Sequential Standard Model (SSM) à Z’ is same as Z but more massive. à LHC cross section is same as for Z scaled by (M Z /M Z’ ) 2. Small.

Robert Harris, Fermilab12 Extra Dimensions: Randall-Sundrum Gravitons l Randall-Sundrum Model  Adds 1 small extra dimension   Warps spacetime by exp(-2kr c  ) è Results in a possible solution to Plank scale hierarchy problem. l Predicts Graviton Resonances, G. è Massive spin-2 particles  G  fermion pairs, boson pairs l Model has two parameters è Mass of lightest graviton resonance è Coupling parameter k / M PL à Usually considered to be 0.1 or less. l Dijet production at LHC  q qbar, gg  G  q qbar, gg. è Cross section small except at low mass where benefits from gg process. gravity localized at  =0, exponentially weaker at  =  Solution to Hierarchy Problem Masses of particles on our brane exponentially reduced from Planck scale masses m 0. m = m 0 exp(-kr c  ) Planck brane Our brane

Robert Harris, Fermilab13 Model-less Motivation l Theoretical Motivation è The many models of dijet resonances are ample theoretical motivation. è But experimentalists should not be biased by theoretical motivations... l Experimental Motivation è The LHC collides partons (quarks, antiquarks and gluons). à LHC is a parton-parton resonance factory in a previously unexplored region à Motivation to search for dijet resonances and contact interactions is obvious ð We must do it. è We search for generic dijet resonances, not specific models. à Nature may surprise us with unexpected new particles. à One search encompasses ALL narrow dijet resonances. è We search for deviations in dijet angular distributions vs. dijet mass à Now the search is focused on a model of quark contact interactions. à It will also be applicable for generic parton contact interactions. à And essential for confirming and understanding any resonances seen.

Robert Harris, Fermilab14 Conclusions l There is a long list of new physics models that produce dijets. l Perhaps no single model of physics with dijets is compelling enough to warrant a dedicated search. l But the breadth of possibilities increases our chances of finding new physics. l This is because so many phenomena couple to quarks, anti-quarks and gluons. l Lets not invest too much effort in any particular model: nature’s choice may not have been anticipated by us. “There is more underneath heaven on earth, Horatio, than is dreamed of in your philosophy” William Shakespeare