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Integrand-reduction techniques for NLO and beyond
http://ilcdoc.linearcollider.org/record/63002
After a brief general introduction about the integrand-reduction method, we will review the main features of the GoSam 2.0 automated framework for one-loop calculations and illustrate its application to SM processes involving the production of massive particles in conjunction with jets and photons. These results have been obtained by interfacing GoSam with different Monte Carlo frameworks, thus combining the NLO calculation with parton shower effects. In the second part of the presentation, we will focus on the applications of GoSam beyond NLO. The code has already been used within NNLO calculations for the computation of real-virtual contributions and for the evaluation of the hard functions needed by approximate NNLO and resummation techniques. We will finally briefly discuss a promising approach for the reduction of scattering amplitudes beyond one loop based on integrand reduction via multivariate polynomial division.Ossola, GiovanniTue, 19 Jan 2016 10:29:23 GMThttp://ilcdoc.linearcollider.org/record/630022016NNLO QCD corrections for Z boson plus jet production
http://ilcdoc.linearcollider.org/record/63001
We discuss the next-to-next-to-leading order (NNLO) QCD corrections to Z boson production in association with a jet including all partonic channels at all color levels and including the leptonic decay of the Z boson. We focus on the optimization of the numerical evaluation of the double-real contribution and demonstrate that our procedure for spreading the Monte Carlo integration over $\mathcal{O}(1000)$ cores and recombining the results afterwards lead to stable results with sensible error estimates. We apply representative cuts on the jet and charged lepton transverse momenta and pseudorapidities at LHC energies and present the transverse momentum and rapidity distributions of the charged leptons.Ridder, A Gehrmann-DeTue, 19 Jan 2016 10:29:23 GMThttp://ilcdoc.linearcollider.org/record/630012016NLO efforts in Herwig++
http://ilcdoc.linearcollider.org/record/63000
With the advent and recent extension of the BLHA standard to interface Monte Carlo event generators and one-loop matrix element providers, the Herwig++ event generator has expanded its range of applicability to a multitude of underlying hard processes at NLO QCD. The new NLO development is centered around the Matchbox framework, which turns fixed NLO QCD calculations into parton shower matched calculations - to be matched to the two parton shower variants of Herwig++. Matchbox provides thereby for the automated setup of the underlying fixed NLO QCD calculations and the interface to the one-loop matrix element providers, as well as for an efficient and automated multi-channel phase space sampling, and forms the basis for the NLO capabilities of the new release of Herwig++. Along with several other new features and developments, the new release marks the end of distinguishing Herwig++ and (Fortran) HERWIG, and constitutes the first major release of version 7 of the Herwig event generator.Reuschle, ChristianTue, 19 Jan 2016 10:29:23 GMThttp://ilcdoc.linearcollider.org/record/630002016Four-loop relation between the $\bar{\rm MS}$ and on-shell quark mass
http://ilcdoc.linearcollider.org/record/62998
In this contribution we discuss the four-loop relation between the on-shell and $\bar{\rm MS}$ definition of heavy quark masses which is applied to the top, bottom and charm case. We also present relations between the $\bar{\rm MS}$ quark mass and various threshold mass definitions and discuss the uncertainty at next-to-next-to-next-to-leading order.Marquard, PeterMon, 18 Jan 2016 10:27:35 GMThttp://ilcdoc.linearcollider.org/record/629982016Higher-order corrections to the splitting functions from differential equations in QCD
http://ilcdoc.linearcollider.org/record/62997
We report on the status an ab initio computation of the time-like splitting functions at next-to-next-to-leading order in QCD. Time-like splitting functions govern the collinear kinematics of inclusive hadron production in $e^+e^-$ annihilation and the evolution of the parton fragmentation distributions. Current knowledge about them at three loops has been inferred by means of crossing symmetry from their related space-like counterparts, the deep-inelastic structure functions and parton densities. In this approach certain parts of the off-diagonal quark-gluon splitting function are left undetermined, which calls for an independent calculation from first principles. We outline the method for calculating master integrals from differential equations which are required to attack the problem.Gituliar, OFri, 15 Jan 2016 10:22:30 GMThttp://ilcdoc.linearcollider.org/record/629972016The 750 GeV diphoton LHC excess and Extra Z's in Heterotic-String Derived Models
http://ilcdoc.linearcollider.org/record/62996
The ATLAS and CMS collaborations recently recorded possible di-photon excess at 750 GeV and a less significant di-boson excess around 1.9 TeV. Such excesses may be produced in heterotic-string derived Z' models, where the di-photon excess may be connected with the Standard Model singlet scalar responsible for the Z' symmetry breaking, whereas the di-boson excess arises from production of the extra vector boson. Additional vector-like states in the string Z' model are instrumental to explain the relatively large width of the di-photon events and mandated by anomaly cancellation to be in the vicinity of the Z' breaking scale. Wilson line breaking of the non-Abelian gauge symmetries in the string models naturally gives rise to dark matter candidates. Future collider experiments will discriminate between the high-scale heterotic-string models, which preserve the perturbative unification paradigm indicated by the Standard Model data, versus the low scale string models. We also discuss the possibility for the production of the di-photon events with high scale $U(1)_{Z^\prime}$ breaking.Faraggi, Alon EFri, 15 Jan 2016 10:22:29 GMThttp://ilcdoc.linearcollider.org/record/629962016Future Collider Signatures of the Possible 750 GeV State
http://ilcdoc.linearcollider.org/record/62995
If the recent indications of a possible state $\Phi$ with mass $\sim 750$ GeV decaying into two photons reported by ATLAS and CMS in LHC collisions at 13 TeV were to become confirmed, the prospects for future collider physics at the LHC and beyond would be affected radically, as we explore in this paper. Even minimal scenarios for the $\Phi$ resonance and its $\gamma \gamma$ decays require additional particles with masses $\gtrsim \frac12 m_\Phi$. We consider here two benchmark scenarios that exemplify the range of possibilities: one in which $\Phi$ is a singlet scalar or pseudoscalar boson whose production and $\gamma \gamma$ decays are due to loops of coloured and charged fermions, and another benchmark scenario in which $\Phi$ is a superposition of (nearly) degenerate CP-even and CP-odd Higgs bosons in a (possibly supersymmetric) two-Higgs doublet model also with additional fermions to account for the $\gamma \gamma$ decay rate. We explore the implications of these benchmark scenarios for the production of $\Phi$ and its new partners at colliders in future runs of the LHC and beyond, at higher-energy $pp$ colliders and at $e^+ e^-$ and $\gamma \gamma$ colliders, with emphasis on the bosonic partners expected in the doublet scenario and the fermionic partners expected in both scenarios.Djouadi, AbdelhakFri, 15 Jan 2016 10:22:27 GMThttp://ilcdoc.linearcollider.org/record/629952016Search for Sphalerons in Proton-Proton Collisions
http://ilcdoc.linearcollider.org/record/62994
In a recent paper, Tye and Wong (TW) have argued that sphaleron-induced transitions in high-energy proton-proton collisions should be enhanced compared to previous calculations, based on a construction of a Bloch wave function in the periodic sphaleron potential and the corresponding pass band structure. Here we convolute the calculations of TW with parton distribution functions and simulations of final states to explore the signatures of sphaleron transitions at the LHC and possible future colliders. We calculate the increase of sphaleron transition rates in proton-proton collisions at centre-of-mass energies of 13/14/33/100 TeV for different sphaleron barrier heights, while recognising that the rates have large overall uncertainties. We use a simulation to show that LHC searches for microscopic black holes should have good efficiency for detecting sphaleron-induced final states, and discuss their experimental signatures and observability in Run 2 of the LHC and beyond. We recast the early ATLAS Run-2 search for microscopic black holes to constrain the rate of sphaleron transitions at 13 TeV, deriving a significant limit on the sphaleron transition rate for the nominal sphaleron barrier height of 9 TeV.Ellis, JohnFri, 15 Jan 2016 10:22:27 GMThttp://ilcdoc.linearcollider.org/record/629942016NNNLO determination of the bottom-quark mass from non-relativistic sum rules
http://ilcdoc.linearcollider.org/record/62993
The mass of the bottom quark can be determined with high precision from moments of the pair-production cross section sigma(e+ e- -> b bbar) near threshold. We present the first complete NNNLO determination from non-relativistic sum rules, obtaining a bottom-quark mass of mb^PS(2 GeV) = (4.532 +0.013 -0.039) GeV in the potential-subtracted scheme. For the mass in the MSbar scheme we find mb^MS(mb^MS) = (4.203 +0.016 -0.034) GeV using the recently computed four-loop correction to the scheme conversion.Beneke, MartinWed, 13 Jan 2016 10:18:59 GMThttp://ilcdoc.linearcollider.org/record/629932016The growing toolbox of perturbative QCD
http://ilcdoc.linearcollider.org/record/62991
Advances in perturbative QCD techniques have been crucial for the successful interpretation of the data collected in Run I of LHC, and for the discovery of the Higgs boson. I will very briefly highlight some recent additions to the QCD toolbox, and note how these new tools are likely to be essential for future precision physics, both in Run II at the LHC, and in view of future hadron and lepton colliders.Magnea, LorenzoTue, 12 Jan 2016 10:17:06 GMThttp://ilcdoc.linearcollider.org/record/629912016Dominant $\mathcal{O}(\alpha_s\alpha)$ corrections to Drell-Yan processes in the resonance region
http://ilcdoc.linearcollider.org/record/62990
Apart from the well-known NNLO QCD and NLO electroweak corrections to W- and Z-boson production at hadron colliders, the most important fixed-order corrections are given by the mixed QCD-electroweak corrections of $\mathcal{O}(\alpha_s\alpha)$. The knowledge of these corrections is of particular importance to control the theoretical uncertainties in the upcoming high-precision measurements of the W-boson mass and the effective weak mixing angle at the LHC. Since these observables are dominated by the phase-space regions of resonant W/Z bosons, we address the $\mathcal{O}(\alpha_s\alpha)$ corrections in the framework of an expansion about the W/Z poles. Retaining only the leading, resonant contribution in the so-called pole approximation, the corrections can be classified into factorizable and non-factorizable contributions. In this article we review our calculation of the numerically dominant corrections which arise from factorizable corrections of "initial-final" type, i.e. they combine the QCD corrections to the production with the large electroweak corrections to the decay of the W/Z boson. Moreover, we compare our results to simpler approximate combinations of electroweak and QCD corrections based on naive products of NLO QCD and electroweak correction factors and using leading-logarithmic approximations for QED final-state radiation. Finally, we estimate the shift in the W-boson mass that results from the $\mathcal{O}(\alpha_s\alpha)$ corrections to the transverse-mass distribution.Dittmaier, StefanTue, 12 Jan 2016 10:17:06 GMThttp://ilcdoc.linearcollider.org/record/629902016Neutralino Pair Production at the Photon-Photon Collider for the $\tilde{\tau}$-Coannihilation Scenario
http://ilcdoc.linearcollider.org/record/62989
Supersymmetry (SUSY) is a theory that gives an explanation for the strong and electroweak interactions from the grand unification scale down to the weak scale. The search for supersymmetric particles still continues at full speed at the LHC without success. The main tasks at the ILC is complementing the LHC result and also search for new physics. In this study, the neutralino pair production via photon-photon collision is studied for the $\tilde{t}$-coannihilation scenario in the context of MSSM at the ILC. In the calculation, all the possible one-loop diagrams are taken into account for the photon-photon interaction. We present the production cross section and distribution of various observables for the lightest and next-to-lightest neutralino pairs for benchmark models which are specifically presented in the light of LHC8 data analysis, employing these benchmark models for neutralino pair production could show the potential of the ILC concerning the dark matter searches in supersymmetry.Sonmez, NasufMon, 11 Jan 2016 10:15:23 GMThttp://ilcdoc.linearcollider.org/record/629892016Charged Higgs Pair Production in THDM Through Photon-photon Collisions at the ILC
http://ilcdoc.linearcollider.org/record/62988
In this study, the charged Higgs pair production is analyzed for the minimal extension of the standard model called two-higgs-doublet model. The process $\gamma\gamma\rightarrow H^+H^-$ is calculated at the tree level for the ILC and the numerical analysis is presented for various parameters. The production rate of the charged Higgs boson pair as a function of center-of-mass (CM) energy and the differential cross section as a function of angle between photon and positive charged Higgs boson is presented. The cross section gets high at the low charged Higgs mass and low CM energies. The total integrated cross section of the process is also calculated at a $e^+e^-$-collider by convoluting the $\gamma\gamma\rightarrow H^+H^-$ subprocess with the photon luminosity of the backscattered photons. The total integrated cross section peaks around $\sqrt{s}=650 \;\text{GeV}$ and have a value of $1.4 \;\text{pb}$ for $m_{H^\pm}=100\;\text{GeV/c}^2$. Charged Higgs detection is very important sign for the new physics and the results shows the potential of the ILC for the search of the new physics signals.Sonmez, NasufMon, 11 Jan 2016 10:15:23 GMThttp://ilcdoc.linearcollider.org/record/629882016Heavy Neutrinos at Future Colliders
http://ilcdoc.linearcollider.org/record/62987
We discuss the current status and future prospects of heavy neutrino searches at the energy frontier, which might play an important role in vindicating the simplest seesaw paradigm as the new physics responsible for neutrino mass generation. After summarizing the current search limits and potential improvements at hadron colliders, we highlight the unparalleled sensitivities achievable in the clean environment of future lepton colliders.Dev, P S BhupalFri, 08 Jan 2016 10:10:20 GMThttp://ilcdoc.linearcollider.org/record/629872016Higgs boson production in the $U(1)_{B-L}$ model at the ILC
http://ilcdoc.linearcollider.org/record/62986
In the framework of the minimal $U(1)_{B-L}$ extension of the Standard Model, we investigate the Higgs boson production processes $e^{+}e^{-}\rightarrow ZH$, $e^{+}e^{-}\rightarrow \nu_{e}\bar{\nu_{e}}H$, $e^{+}e^{-}\rightarrow t\bar{t}H$, $e^{+}e^{-}\rightarrow ZHH$ and $e^{+}e^{-}\rightarrow \nu_{e}\bar{\nu_{e}}HH$ at the International Linear Collider (ILC). We present the production cross sections, the relative corrections and compare our results with the expected experimental accuracies for Higgs decay channel $H\rightarrow b\bar{b}$. In the allowed parameter space, we find that the effects of the three single Higgs boson production processes might approach the observable threshold of the ILC, and that the Higgs signal strengths $\mu_{b\bar{b}}$ of the two double Higgs boson production processes are all out of the observable threshold of the ILC so that the effects will be difficult to be observed at the ILC.Han, JinzhongTue, 05 Jan 2016 10:05:00 GMThttp://ilcdoc.linearcollider.org/record/629862016Constraining Natural SUSY via the Higgs Coupling and the Muon Anomalous Magnetic Moment Measurements
http://ilcdoc.linearcollider.org/record/62985
We use the Higgs coupling and the muon anomalous magnetic moment measurements to constrain the parameter space of the natural supersymmetry (SUSY) in the Generalized Minimal Supergravity (GmSUGRA) model. We scan the parameter space of the GmSUGRA model with small electroweak fine-tuning measure ($\Delta_{\rm EW} \leq 100$). The parameter space after applying various sparticle mass bounds, Higgs mass bounds, B-physics bounds, the muon magnetic moment constraint, and the Higgs coupling constraint from measurements at HL-LHC, ILC, and CEPC, is shown in the planes of various interesting model parameters and sparticle masses. Our study indicates that the Higgs coupling and muon anomalous magnetic moment measurements can constrain the parameter space effectively. It is shown that $\Delta_{\rm EW}\sim$ 30, consistence with all constraints, and having supersymmetric contributions to the muon anomalous magnetic moment within 1$\sigma$ can be achieved. The precision of $k_b$ and $k_{\tau}$ measurements at CEPC can bound $m_A$ to be above 1.2 TeV and 1.1 TeV respectively. The combination of the Higgs coupling measurement and muon anomalous magnetic moment measurement constrain $\tilde{e}_R$ mass to be in the range from 0.6 TeV to 2 TeV. The range of both $\tilde{e}_L$ and $\tilde{\nu}_e$ masses is 0.4 TeV $\sim$ 1.2 TeV. In all cases, the $\tilde{\chi}_1^0$ mass needs to be small (mostly $\leq$ 400 GeV). The comparison of bounds in the $\tan\beta - m_A$ plane shows that the Higgs coupling measurement is complementary to the direct collider searches for heavy Higgs when constraining the natural SUSY. A few mass spectra in the typical region of parameter space after applying all constraints are shown as well.Li, TianjunTue, 05 Jan 2016 10:05:00 GMThttp://ilcdoc.linearcollider.org/record/629852016A data-driven approach to pile-up at high luminosity
http://ilcdoc.linearcollider.org/record/62984
We discuss recent results on pile-up based on a data-driven jet-mixing method. We illustrate prospects for experimental searches and precision studies in high pile-up regimes at high-luminosity hadron colliders, showing how the jet mixing approach can be used, also outside tracker acceptances, to treat correlation observables and effects of hard jets from pile-up.Hautmann, FThu, 31 Dec 2015 09:56:19 GMThttp://ilcdoc.linearcollider.org/record/629842015Revisiting Scalar Quark Hidden Sector in Light of 750-GeV Diphoton Resonance
http://ilcdoc.linearcollider.org/record/62983
In this short note, we revisit the model of a CP-even singlet scalar resonance proposed in arXiv:1507.02483, where the resonance appears as the lightest composite state made of scalar quarks participating in hidden strong dynamics. We show that the model can consistently explain the excess of diphoton events with an invariant mass around 750GeV reported by both the ATLAS and CMS experiments. We also discuss the nature of the charged composite states in the TeV range which accompany to the neutral scalar. Due to inseparability of the dynamical scale and the mass of the resonance, the model also predicts signatures associated with the hidden dynamics such as leptons, jets along with multiple photons at future collider experiments. We also associate the TeV-scale dynamics behind the resonance with an explanation of dark matter.Chiang, Cheng-WeiThu, 31 Dec 2015 09:56:19 GMThttp://ilcdoc.linearcollider.org/record/629832016A Megaxion at 750 GeV as a First Hint of Low Scale String Theory
http://ilcdoc.linearcollider.org/record/62982
Low scale string models naturally have axion-like pseudoscalars which couple directly to gluons and photons (but not $W$s) at tree level. We show how they typically get tree level masses in the presence of closed string fluxes, consistent with the axion discrete gauge symmetry, in a way akin of the axion monodromy of string inflation and relaxion models. We discuss the possibility that the hints for a resonance at 750 GeV recently reported at ATLAS and CMS could correspond to such a heavy axion state (megaxion). Adjusting the production rate and branching ratios suggests the string scale to be of order $M_s$ ~ $7 - 10^4$ TeV, depending on the compactification geometry. If this interpretation was correct, one extra $Z'$ gauge boson could be produced before reaching the string threshold at LHC and future colliders.Ibanez, Luis EThu, 31 Dec 2015 09:56:19 GMThttp://ilcdoc.linearcollider.org/record/629822016SIMP Spectroscopy
http://ilcdoc.linearcollider.org/record/62981
We study the interactions between strongly interacting massive particle dark matter and the Standard Model via a massive vector boson that is kinetically mixed with the hypercharge gauge boson. The relic abundance is set by 3-to-2 self-interactions of the dark matter, while the interactions with the vector mediator enable kinetic equilibrium between the dark and visible sectors. We show that a wide range of parameters is phenomenologically viable and can be probed in various ways. Astrophysical and cosmological constraints are evaded due to the p-wave nature of dark matter annihilation into visible particles, while direct detection methods using electron recoils can be sensitive to parts of the parameter space. In addition, we propose performing spectroscopy of the strongly coupled dark sector at e+e- colliders, where the energy of a mono-photon can track the resonance structure of the dark sector. Alternatively, some resonances may decay back into Standard Model leptons or jets, realizing `hidden valley' phenomenology at the LHC and ILC in a concrete fashion.Hochberg, YonitTue, 29 Dec 2015 09:52:51 GMThttp://ilcdoc.linearcollider.org/record/629812015In vacuum diamond sensor scanner for beam halo measurements in the beam line at the KEK Accelerator Test Facility
http://ilcdoc.linearcollider.org/record/62980
The investigation of beam halo transverse distributions is important for the understanding of beam losses and the control of backgrounds in Future Linear Colliders (FLC). A novel in vacuum diamond sensor (DSv) scanner with four strips has been designed and developed for the investigation of the beam halo transverse distributions and also for the diagnostics of Compton recoil electrons after the interaction point (IP) of ATF2, a low energy (1.3 GeV) prototype of the final focus system for the ILC and CLIC linear collider projects. Using the DSv, a dynamic range of $\sim10^6$ has been successfully demonstrated and confirmed for the first time by simultaneous beam core ($\sim10^9$ electrons) and beam halo ($\sim10^3$ electrons) measurements at ATF2. This report presents the characterization, performance studies and tests of the diamond sensors using an $\alpha$ source as well as using the electron beams at PHIL, a low energy ($< 10$ MeV) photo-injector at LAL, and at ATF2. First beam halo measurement results using the DSv at ATF2 with different beam intensities and vacuum levels are also presented. Such measurements not only allow one to evaluate the different sources of beam halo generation but also to define the requirements for a suitable collimation system to be installed at ATF2, as well as to optimize its performance during future operation.Liu, ShanTue, 29 Dec 2015 09:52:51 GMThttp://ilcdoc.linearcollider.org/record/629802015How the $\gamma \gamma$ Resonance Stole Christmas
http://ilcdoc.linearcollider.org/record/62979
The experimental and theoretical implications of heavy di-gauge boson resonances that couple to, or are comprised of, new charged and strongly interacting matter are investigated. Observation and measurement of ratios of the resonant di-gauge boson channels $WW$, $ZZ$, $\gamma \gamma$, $Z \gamma$, and $gg$ in the form of di-jets, provide a rather direct -- and for some ratios a rather robust -- probe of the gauge representations of the new matter. For a spin-zero resonance with the quantum numbers of the vacuum, the ratios of resonant $WW$ and $ZZ$ to $\gamma \gamma$ channels, as well as the longitudinal versus transverse polarization fractions in the $WW$ and $ZZ$ channels, provide extraordinarily sensitive probes for possible mixing with the Higgs boson, while di-Higgs and di-top resonant channels, $hh$ and $tt$, provide somewhat less sensitivity. We present a survey of possible underlying models for di-gauge boson resonances by considering various limits for the mass of the new charged and strongly interacting matter fields as well as the confinement scale of new hyper-gauge interactions under which they may also be charged. In these limits, resonances may be included as elementary weakly coupled spin-zero states or can correspond to hyper-glueballs, hyper-onia, or pseudo-scalar hyper-mesons. For each of these cases, we make predictions for additional states that could be resonantly or pair-produced and observed at the Large Hadron Collider or in future collider experiments. Heavy di-gauge boson resonances can provide a unified explanation for a number of small discrepancies and excesses in reported data from the Large Hadron Collider.Craig, NathanielFri, 25 Dec 2015 09:46:12 GMThttp://ilcdoc.linearcollider.org/record/629792015Scalar singlets at present and future colliders
http://ilcdoc.linearcollider.org/record/62978
A scalar singlet, coupled to the other particles only through its mixing with the Higgs boson, appears in several motivated extensions of the Standard Model. The prospects for the discovery of a generic singlet at the various stages of the LHC, as well as at future high-energy colliders, are studied, and the reach of direct searches is compared with the precision attainable with Higgs couplings measurements. The results are then applied to the NMSSM and Twin Higgs.Buttazzo, DarioThu, 24 Dec 2015 09:44:27 GMThttp://ilcdoc.linearcollider.org/record/629782015Study on CEPC performances with different collision energies and geometric layouts
http://ilcdoc.linearcollider.org/record/62977
Circular Electron-Positron Collider(CEPC) is one of the largest plans in high energy physics study at China, which would serve as Higgs Factory firstly and then upgrade to a hadron collider. In this paper we give the 50km and 100km design in both single ring and double ring schemes, including $Z$ boson and $W$ boson and Higgs boson by using the optimized method. Also, we give the potential of CEPC running at $Z$ and $W$ poles. And we analysis the relationship of luminosity with circumference and filling factor, which gives a way to evaluate the choice of geometry. What's more, we compare the nominal performance of CEPC-SPPC and LHC and FCC.Xiao, MingThu, 24 Dec 2015 09:44:26 GMThttp://ilcdoc.linearcollider.org/record/629772015Gauge Mediated Mini-Split
http://ilcdoc.linearcollider.org/record/62976
We propose a simple model of split supersymmetry from gauge mediation. This model features gauginos that are parametrically a loop factor lighter than scalars, accommodates a Higgs boson mass of 125 GeV, and incorporates a simple solution to the $\mu-b_\mu$ problem. The gaugino mass suppression can be understood as resulting from collective symmetry breaking. Imposing collider bounds on $\mu$ and requiring viable electroweak symmetry breaking implies small $a$-terms and small $\tan \beta$ -- the stop mass ranges from $10^5$ to $10^8 \mbox{ GeV}$. In contrast with models with anomaly + gravity mediation (which also predict a one-loop loop suppression for gaugino masses), our gauge mediated scenario predicts aligned squark masses and a gravitino LSP. Gluinos, electroweakinos and Higgsinos can be accessible at the LHC and/or future colliders for a wide region of the allowed parameter space.Cohen, TimothyTue, 22 Dec 2015 09:40:50 GMThttp://ilcdoc.linearcollider.org/record/629762015