Open Access. Powered by Scholars. Published by Universities.®
Physical Sciences and Mathematics Commons™
Open Access. Powered by Scholars. Published by Universities.®
- Keyword
-
- High energy physics phenomenology (21)
- Neutralinos (8)
- EDM (5)
- CP phases (4)
- CP violation (4)
-
- High energy physics (4)
- LHC (4)
- CP violating phases (3)
- Gauge supersymmetry (3)
- Global supersymmetry (3)
- Higgs sector (3)
- PAMELA (3)
- SU(5) (3)
- Supergravity models (3)
- Vectorlike multiplets (3)
- WMAP (3)
- Yukawa couplings (3)
- B quark mass (2)
- Cancellation mechanism (2)
- Effective Lagrangian (2)
- Electric dipole moment (2)
- Electroweak symmetry (2)
- Gluinos (2)
- Higgs couplings (2)
- LHC-7 (2)
- Lagrangian (2)
- Loop corrections (2)
- MSSM (2)
- Muon anomaly (2)
- Neutrinos (2)
Articles 1 - 30 of 94
Full-Text Articles in Physical Sciences and Mathematics
Ultraviolet Finiteness Of All Quantum Loops In Gauge Supersymmetry, Pran Nath, R. Arnowitt
Ultraviolet Finiteness Of All Quantum Loops In Gauge Supersymmetry, Pran Nath, R. Arnowitt
Pran Nath
The arbitrary n-point Green's functions of spontaneously broken gauge supersymmetry are shown to be ultraviolet finite to arbitrary loop order for N>~2 (where 4N is the number of Fermi coordinates) when the spontaneous breaking preserves global supersymmetry.
Supersymmetry Signals In Leptonic Decays Of W And Z Bosons, R. Arnowitt, Pran Nath
Supersymmetry Signals In Leptonic Decays Of W And Z Bosons, R. Arnowitt, Pran Nath
Pran Nath
It is shown that opposite-sign dilepton events from Z decay represent an excellent signal for supersymmetry if mW̃Z/2 in certain kinematic domains where the standard-model background from Z→τ⁺τ⁻ is absent. Excess of monoleptonic events from W→W̃γ̃ consistent with UA1 cuts is also computed. Comparison with existing data is made.
Chromoelectric Dipole Moment Of The Top Quark In Models With Vectorlike Multiplets, Tarek Ibrahim, Pran Nath
Chromoelectric Dipole Moment Of The Top Quark In Models With Vectorlike Multiplets, Tarek Ibrahim, Pran Nath
Pran Nath
The chromoelectric dipole moment of the top quark is calculated in a model with a vectorlike multiplet, which mixes with the third generation in an extension of the minimal supersymmetric standard model. Such mixings allow for new CP violating phases. Including these new CP phases, the chromoelectric dipole moment that generates an electric dipole of the top in this class of models is computed. The top chromoelectric dipole moment operator arises from loops involving the exchange of the W, the Z, as well as from the exchange involving the charginos, the neutralinos, the gluino, and the vectorlike multiplet and their …
U(1) Problem: Current Algebra And The Θ Vacuum, Pran Nath, R. Arnowitt
U(1) Problem: Current Algebra And The Θ Vacuum, Pran Nath, R. Arnowitt
Pran Nath
The effective Lagrangian which gives a full solution of the U(1) problem is obtained from the 1/N expansion of quantum chromodynamics. This Lagrangian satisfies all the anomalous n-point Ward identities for arbitrary q2, and includes chiral and SU(3) breaking. The relationship between the η′ mass and the θ dependence of the vacuum energy in the absence of quarks and the form of the strong CP violation in the effective-Lagrangian framework are deduced.
Top Quark Electric Dipole Moment In A Minimal Supersymmetric Standard Model Extension With Vectorlike Multiplets, Tarek Ibrahim, Pran Nath
Top Quark Electric Dipole Moment In A Minimal Supersymmetric Standard Model Extension With Vectorlike Multiplets, Tarek Ibrahim, Pran Nath
Pran Nath
The electric dipole moment (EDM) of the top quark is calculated in a model with a vector like multiplet which mixes with the third generation in an extension of the minimal supersymmetric standard model. Such mixings allow for new CP violating phases. Including these new CP phases, the EDM of the top in this class of models is computed. The top EDM arises from loops involving the exchange of the W, the Z as well as from the exchange involving the charginos, the neutralinos, the gluino, and the vector like multiplet and their superpartners. The analysis of the EDM of …
Neutron And Electron Electric Dipole Moment In N=1 Supergravity Unification, Tarek Ibrahim, Pran Nath
Neutron And Electron Electric Dipole Moment In N=1 Supergravity Unification, Tarek Ibrahim, Pran Nath
Pran Nath
An analysis of the neutron EDM and of the electron EDM in minimal N=1 supergravity unification with two CP-violating phases is given. For the neutron the analysis includes the complete one loop gluino, chargino, and neutralino exchange diagrams for the electric dipole and the chromoelectric dipole operators, and also the contribution of the purely gluonic dimension-six operator. It is shown that there exist significant regions in the six-dimensional parameter space of the model where cancellations between the gluino and the chargino exchanges reduce the electric and the chromoelectric contributions, and further cancellations among the electric, the chromoelectric, and the purely …
Neutralino Exchange Corrections To The Higgs Boson Mixings With Explicit Cp Violation, Tarek Ibrahim, Pran Nath
Neutralino Exchange Corrections To The Higgs Boson Mixings With Explicit Cp Violation, Tarek Ibrahim, Pran Nath
Pran Nath
A calculus for the derivatives of the eigenvalues of the neutralino mass matrix with respect to the CP violating background fields is developed and used to compute the mixings among the CP even and the CP odd Higgs sectors arising from the inclusion of the neutralino sector consisting of the neutralino, the Z boson, and the neutral Higgs bosons (χi⁰-Z-h⁰-H⁰) exchange in the loop contribution to the effective potential including the effects of large CP violating phases. Along with the top squark, bottom squark, tau slepton and chargino–W–charged-Higgs-boson (χ⁺-W-H⁺) contributions computed previously the present analysis completes the one loop corrections …
Probing Supergravity Grand Unification In The Brookhaven G-2 Experiment, Utpal Chattopadhyay, Pran Nath
Probing Supergravity Grand Unification In The Brookhaven G-2 Experiment, Utpal Chattopadhyay, Pran Nath
Pran Nath
A quantitative analysis of aμ≡1/2(g-2)μ within the framework of supergravity grand unification and radiative breaking of the electroweak symmetry is given. It is found that aμSUSY is dominated by the chiral interference term from the light chargino exchange, and that this term carries a signature which correlates strongly with the sign of μ. Thus as a rule aμSUSY>0 for μ>0 and aμSUSYμtanβ∼1. At the quantitative level it is shown that if the E821 BNL experiment can reach the expected sensitivity of 4×10⁻1⁰ and there is a reduction in the hadronic error by a factor of 4 or more, …
Weak Isospin Violations In Charged And Neutral Higgs Couplings From Supersymmetric Loop Corrections, Tarek Ibrahim, Pran Nath
Weak Isospin Violations In Charged And Neutral Higgs Couplings From Supersymmetric Loop Corrections, Tarek Ibrahim, Pran Nath
Pran Nath
The supersymmetric QCD and the supersymmetric electroweak loop corrections to the violations of weak isospin to Yukawa couplings are investigated. Specifically it involves an analysis of the supersymmetric (SUSY) loop corrections to the Higgs couplings to the third generation quarks and leptons. Here we analyze the SUSY loop corrections to the charged Higgs couplings which are then compared with the supersymmetric loop corrections to the neutral Higgs couplings previously computed. It is found that the weak isospin violations can be quite significant, i.e., as much as 40–50% or more of the total loop correction to the Yukawa coupling. The effects …
Large Τ And Τ Neutrino Electric Dipole Moments In Models With Vectorlike Multiplets, Tarek Ibrahim, Pran Nath
Large Τ And Τ Neutrino Electric Dipole Moments In Models With Vectorlike Multiplets, Tarek Ibrahim, Pran Nath
Pran Nath
It is shown that the electric dipole moment of the τ lepton several orders of magnitude larger than predicted by the standard model can be generated from mixings in models with vectorlike mutiplets. The electric dipole moment (EDM) of the τ lepton arises from loops involving the exchange of the W, the charginos, the neutralinos, the sleptons, the mirror leptons, and the mirror sleptons. The EDM of the Dirac τ neutrino is also computed from loops involving the exchange of the W, the charginos, the mirror leptons, and the mirror sleptons. A numerical analysis is presented, and it is shown …
Modular Invariant Soft Breaking, Wmap, Dark Matter, And Sparticle Mass Limits, Utpal Chattopadhyay, Pran Nath
Modular Invariant Soft Breaking, Wmap, Dark Matter, And Sparticle Mass Limits, Utpal Chattopadhyay, Pran Nath
Pran Nath
An analysis of soft breaking under the constraint of modular invariance is given. The role of dilaton and moduli dependent front factors in achieving a modular invariant Vsoft is emphasized. Further, it is shown that in string models tanβ is no longer a free parameter but is determined in terms of αstring and the other soft parameters by the constraints of modular invariance and radiative electroweak symmetry breaking. The above framework is then used to analyze the neutralino relic density consistent with the Wilkinson Microwave Anisotropy Probe (WMAP) data at self-dual points in the Kähler and complex structure moduli. One …
Landscape Of Supersymmetric Particle Mass Hierarchies And Their Signature Space At The Cern Large Hadron Collider, Daniel Feldman, Zuowei Liu, Pran Nath
Landscape Of Supersymmetric Particle Mass Hierarchies And Their Signature Space At The Cern Large Hadron Collider, Daniel Feldman, Zuowei Liu, Pran Nath
Pran Nath
The minimal supersymmetric standard model with soft breaking has a large landscape of supersymmetric particle mass hierarchies. This number is reduced significantly in well-motivated scenarios such as minimal supergravity and alternatives. We carry out an analysis of the landscape for the first four lightest particles and identify at least 16 mass patterns, and provide benchmarks for each. We study the signature space for the patterns at the CERN Large Hadron Collider by analyzing the lepton+ (jet≥2) + missing PT signals with 0, 1, 2, and 3 leptons. Correlations in missing PT are also analyzed. It is found that even with …
R-B In Supergravity Grand Unification With Nonuniversal Soft Supersymmetry Breaking, Tarakeshwar Dasgupta, Pran Nath
R-B In Supergravity Grand Unification With Nonuniversal Soft Supersymmetry Breaking, Tarakeshwar Dasgupta, Pran Nath
Pran Nath
An analysis of supersymmetric contributions to Rb in supergravity grand unification with nonuniversal boundary conditions on soft supersymmetry breaking in the scalar sector is given. Effects on Rb of Planck scale corrections on gaugino masses are also analyzed. It is found that there exist regions of the parameter space where positive corrections to Rb of size ∼1σ can be gotten. The region of the parameter space where enhancement of Rb occurs is identified. Predictions of sparticle masses for the maximal Rb case are given. The analysis has implications for the discovery of supersymmetric particles at colliders.
Sensitivity Of Supersymmetric Dark Matter To The B Quark Mass, Mario E. Gomez, Tarek Ibrahim, Pran Nath, Solveig Skadhauge
Sensitivity Of Supersymmetric Dark Matter To The B Quark Mass, Mario E. Gomez, Tarek Ibrahim, Pran Nath, Solveig Skadhauge
Pran Nath
An analysis of the sensitivity of supersymmetric dark matter to variations in the b quark mass is given. Specifically we study the effects on the neutralino relic abundance from supersymmetric loop corrections to the mass of the b quark. It is known that these loop corrections can become significant for large tanβ. The analysis is carried out in the framework of MSUGRA and we focus on the region where the relic density constraints are satisfied by resonant annihilation through the s-channel Higgs poles. We extend the analysis to include CP phases taking into account the mixing of the CP-even and …
Neutron And Lepton Electric Dipole Moments In The Minimal Supersymmetric Standard Model, Large Cp Violating Phases, And The Cancellation Mechanism, Tarek Ibrahim, Pran Nath
Neutron And Lepton Electric Dipole Moments In The Minimal Supersymmetric Standard Model, Large Cp Violating Phases, And The Cancellation Mechanism, Tarek Ibrahim, Pran Nath
Pran Nath
An analysis of the electric dipole moment (EDM) of the neutron and of the lepton in the minimal supersymmetric standard model (MSSM) with the most general allowed set of CP violating phases without generational mixing is given. The analysis includes the contributions from the gluino, the chargino and the neutralino exchanges to the electric dipole operator, the chromoelectric dipole operator, and the CP violating purely gluonic dimension six operator. It is found that the EDMs depend only on certain combinations of the CP phases. The independent set of such phases is classified. The analysis of the EDMs given here provides …
Event Rates In Dark Matter Detectors For Neutralinos Including Constraints From B →Sγ Decay, Pran Nath, R. Arnowitt
Event Rates In Dark Matter Detectors For Neutralinos Including Constraints From B →Sγ Decay, Pran Nath, R. Arnowitt
Pran Nath
Event rates for neutralino-nucleus scattering are studied including the constraint arising from the recent CLEO results on b→sγ using the cold hot dark matter (CHDM) model. It is found that the CLEO results strongly affect the supersymmetric spectrum and the event rates. The analysis given here uses the accurate method for the computation of the relic density and leads to a dip in the event rate when the neutralino mass is ∼MZ/2 due to the Z pole and ∼mh/2 due to the Higgs pole. The effect of the new Δq determinations on event rates is also discussed.
Yukawa Couplings And Quark And Lepton Masses In An So(10) Model With A Unified Higgs Sector, Pran Nath, Raza M. Syed
Yukawa Couplings And Quark And Lepton Masses In An So(10) Model With A Unified Higgs Sector, Pran Nath, Raza M. Syed
Pran Nath
Fermion mass generation for the third generation is considered within a unified Higgs model with a single pair of vector-spinor 144+144̅ of Higgs multiplets. Extending a previous work it is shown that much larger masses can arise for all the third generation fermions from mixing with 45 and 120 matter multiplets via the cubic couplings 16·45·144̅ and 16·120·144 in addition to the quartic couplings. Further, it is found that values of tanβ as low as 10 can allow for a b-τ-t unification consistent with the current data. The quartic and cubic couplings naturally lead to Dirac as well as Majorana …
Intermediate Mass Scale In Rank-Six Superstring Models, R. Arnowitt, Pran Nath
Intermediate Mass Scale In Rank-Six Superstring Models, R. Arnowitt, Pran Nath
Pran Nath
The current experimental lower limit on proton lifetime from the decay mode p→ν¯+K⁺ is used to obtain a limit on the intermediate mass scale in superstring-inspired models with rank-six groups. It is shown that the intermediate mass scale breaking in these models can be as low as 1×101⁴ GeV without violating current proton-decay data, provided the Yukawa couplings of superstring models are no larger than the corresponding couplings in SU(5) supergravity models. Scalar-quark masses are then larger than 1 TeV and the photino mass is no more than a few gigaelectronvolts.
Symmetry Breaking In Three-Generation Calabi-Yau Manifolds, Pran Nath, R. Arnowitt
Symmetry Breaking In Three-Generation Calabi-Yau Manifolds, Pran Nath, R. Arnowitt
Pran Nath
The spontaneous breaking of [SU(3)]3 symmetry to SU(3)×SU(2)×U(1) due to nonrenormalizable interactions in the three-generation Calabi-Yau superstring model is considered. It is seen that these models lead naturally to intermediate scales MI∼101⁵ GeV with simultaneous formation of N and νc vacuum expectation values (VEV’s). The lowest-lying extrema automatically preserve matter parity and hence protect the model against too rapid proton decay. Models with matter parity also protect against electroweak Higgs VEV’s from forming at MI. The intermediate mass scale produces some particles with mass O(MI). It also implies the existence of others with mass ∼1 TeV, which are possibly accessible …
Supersymmetric Discovery Potential And Benchmarks For Early Runs At √S=7 Tev At The Lhc, Baris Altunkaynak, Michael Holmes, Pran Nath, Brent D. Nelson, Gregory Peim
Supersymmetric Discovery Potential And Benchmarks For Early Runs At √S=7 Tev At The Lhc, Baris Altunkaynak, Michael Holmes, Pran Nath, Brent D. Nelson, Gregory Peim
Pran Nath
We carry out an analysis of the potential of the Large Hadron Collider (LHC) to discover supersymmetry in runs at √s=7 TeV with an accumulated luminosity of (0.1–2) fb⁻1 of data. The analysis is done with both minimal supergravity and supergravity models with nonuniversal soft breaking. Benchmarks for early discovery with (0.1–2) fb⁻1 of data are given. We provide an update of b-tagging efficiencies in PGS 4 appropriate for LHC analyses. A large number of signature channels are analyzed, and it is shown that each of the models exhibited are discoverable at the 5σ level or more above the standard …
Pamela Positron Excess As A Signal From The Hidden Sector, Daniel Feldman, Zuowei Liu, Pran Nath
Pamela Positron Excess As A Signal From The Hidden Sector, Daniel Feldman, Zuowei Liu, Pran Nath
Pran Nath
The recent positron excess observed in the PAMELA satellite experiment strengthens previous experimental findings. We give here an analysis of this excess in the framework of the Stueckelberg extension of the standard model which includes an extra U(1)ₓ gauge field and matter in the hidden sector. Such matter can produce the right amount of dark matter consistent with the Wilkinson Microwave Anisotropy Probe (WMAP) constraints. Assuming the hidden sector matter to be Dirac fermions it is shown that their annihilation can produce the positron excess with the right positron energy dependence seen in the HEAT, AMS, and the PAMELA experiments. …
Masses Of Superpartners Of Quarks, Leptons, And Gauge Mesons In Supergravity Grand Unified Theories, R. Arnowitt, A. H. Chamseddine, Pran Nath
Masses Of Superpartners Of Quarks, Leptons, And Gauge Mesons In Supergravity Grand Unified Theories, R. Arnowitt, A. H. Chamseddine, Pran Nath
Pran Nath
A class of "realistic" supergravity grand-unified-theory models possessing two W-inos and two Z-inos which lie above and below W± and Z⁰ mass, respectively, are examined. A lower bound on the W-ino mass of ≃ 30 GeV is obtained with an upper bound of ≃ 250 GeV on the Higgs mass. It is shown that the Z⁰ decays prominantly into two W-inos if the mass of the W-ino<~MW/2. The superpartners of quarks and leptons are shown to be approximately degenerate and in some models have mass ≲ 100 GeV.
Low Mass Gluino Within The Sparticle Landscape, Implications For Dark Matter, And Early Discovery Prospects At Lhc-7, Ning Chen, Daniel Feldman, Zuowei Liu, Pran Nath, Gregory Peim
Low Mass Gluino Within The Sparticle Landscape, Implications For Dark Matter, And Early Discovery Prospects At Lhc-7, Ning Chen, Daniel Feldman, Zuowei Liu, Pran Nath, Gregory Peim
Pran Nath
We analyze supergravity models that predict a low mass gluino within the landscape of sparticle mass hierarchies. The analysis includes a broad class of models that arise in minimal and in nonminimal supergravity unified frameworks and in extended models with additional U(1)Xn hidden sector gauge symmetries. Gluino masses in the range (350–700) GeV are investigated. Masses in this range are promising for early discovery at the LHC at √s=7 TeV (LHC-7). The models exhibit a wide dispersion in the gaugino-Higgsino eigencontent of their lightest supersymmetric particles and in their associated sparticle mass spectra. A signature analysis is carried out and …
Nucleon Decay In Supergravity Unified Theories, Pran Nath, A. H. Chamseddine, R. Arnowitt
Nucleon Decay In Supergravity Unified Theories, Pran Nath, A. H. Chamseddine, R. Arnowitt
Pran Nath
A general analysis of nucleon decay in supergravity unified models is given including the full set of W-gaugino, gluino, and Z-gaugino dressing diagrams (with gauge as well as Yukawa interactions at vertices) of LLLL and RRRR dimension-five operators generated by Higgs-triplet exchange. The analysis is carried out within the framework of a model-independent formalism of SU(2)×U(1) breaking in supergravity models. Full symmetry-breaking effects on the vertices as well as all the allowed mass splittings of the supersymmetric particles that enter the dressing diagrams (i.e., W gauginos, Z gauginos, scalar quarks, and scalar leptons) are included. L-R mixing effects on scalar-quark–scalar-lepton …
Superconnections In Extended Supergravity, R. Arnowitt, Pran Nath
Superconnections In Extended Supergravity, R. Arnowitt, Pran Nath
Pran Nath
Closed-form solution for the superspace connections of extended supergravity in terms of supervielbeine are given for arbitrary values of N, and deSitter parameter e. A reduction procedure from the Riemannian geometry is used to deduce the desired solutions
Stueckelberg Z ' Extension With Kinetic Mixing And Millicharged Dark Matter From The Hidden Sector, Daniel Feldman, Zuowei Liu, Pran Nath
Stueckelberg Z ' Extension With Kinetic Mixing And Millicharged Dark Matter From The Hidden Sector, Daniel Feldman, Zuowei Liu, Pran Nath
Pran Nath
An analysis is given of the Stueckelberg extension of the standard model with a hidden sector gauge group U(1)X where the mass growth for the extra gauge boson occurs via the Stueckelberg mechanism, and where the kinetic mixing in the U(1)X×U(1)Y sector is included. Such a kinetic mixing is generic in a broad class of supergravity and string models. We carry out a detailed global fit of the model with the precision CERN LEP data on and off the Z pole, with χ2 within 1% of the χ2 of the standard model fit. Further, it is shown that, in the …
Locally Supersymmetric Grand Unification, A. H. Chamseddine, R. Arnowitt, Pran Nath
Locally Supersymmetric Grand Unification, A. H. Chamseddine, R. Arnowitt, Pran Nath
Pran Nath
A locally supersymmetric grand unification program is proposed which couples the N=1 supergravity multiplet to an arbitrary grand unified gauge group with any number of left-handed chiral multiplets and a gauge vector multiplet. A specific model is discussed where it is shown that not only do the gravitational interactions eliminate the degeneracy of the vacuum state encountered in global supersymmetry, but simultaneously they can break both supersymmetry and SU(2) ⊗ U(1) down to a residual SU(3)c⊗U(1) symmetry at ∼300 GeV.
Spontaneous Symmetry Breaking Of Gauge Supersymmetry, R. Arnowitt, Pran Nath
Spontaneous Symmetry Breaking Of Gauge Supersymmetry, R. Arnowitt, Pran Nath
Pran Nath
Spontaneous symmetry breaking of gauge supersymmetry to global supersymmetry is seen to determine in part the internal-symmetry gauge group through the equations RAB=λgAB. For the case λ≠0 the determination is complete, the resultant group being the U(1) Maxwell-Einstein coordinate group. For λ=0, spontaneous breaking automatically requires parity breakdown in the vacuum, and is consistent with SU(2) ⊗ U(10 ⊗ color.
Origin Of Internal Symmetry, R. Arnowitt, Pran Nath
Origin Of Internal Symmetry, R. Arnowitt, Pran Nath
Pran Nath
The possibility that the internal-symmetry group is a consequence of the gauge invariance of a theory (rather than being phenomenologically chosen) is suggested. For a fully unified theory where all interactions are determined by the gauge invariance, this could come about as a consequence of spontaneous (or dynamical) breakdown. Thus the vacuum state after symmetry breakdown may preserve only a subgroup of a larger arbitrary group of the original unbroken equations. The above suggestion appears to be at least partly realized within the framework of gauge supersymmetry where the local gauge invariance determines all interactions via the field equations RAB …
Supersymmetric Dark Matter And Yukawa Unification, Utpal Chattopadhyay, Achille Corsetti, Pran Nath
Supersymmetric Dark Matter And Yukawa Unification, Utpal Chattopadhyay, Achille Corsetti, Pran Nath
Pran Nath
An analysis of supersymmetric dark matter under the Yukawa unification constraint is given. The analysis utilizes the recently discovered region of the parameter space of models with gaugino mass nonuniversalities where large negative supersymmetric corrections to the b quark mass appear to allow b-τ unification for a positive μ sign consistent with the b⃗s+γ and gμ-2 constraints. In the present analysis we use the revised theoretical determination of aμSM [aμ=(gμ-2)/2] in computing the difference aμexpt-aμSM which takes into account a reevaluation of the light by light contribution, which has a positive sign. The analysis shows that the region of parameter …