Strongly Coupled Semi-Direct Mediation of Supersymmetry Breaking

Strongly coupled semi-direct gauge mediation models of supersymmetry breaking through massive mediators with standard model charges are investigated by means of composite degrees of freedom. Sizable mediation is realized to generate the standard model gaugino masses for a small mediator mass without breaking the standard model symmetries.Comment: 7 pages; v2: the model generalized, gaugino mass corrected; v3: explanations expanded, references adde

Simplified R-Symmetry Breaking and Low-Scale Gauge Mediation

We argue that some of the difficulties in constructing realistic models of low-scale gauge mediation are artifacts of the narrow set of models that have been studied. In particular, much attention has been payed to the scenario in which the Goldstino superfield in an O'Raifeartaigh model is responsible for both supersymmetry breaking and R-symmetry breaking. In such models, the competing problems of generating sufficiently massive gauginos while preserving an acceptably light gravitino can be quite challenging. We show that by sharing the burdens of breaking supersymmetry and R-symmetry with a second field, these problems are easily solved even within the O'Raifeartaigh framework. We present explicit models realizing minimal gauge mediation with a gravitino mass in the eV range that are both calculable and falsifiable.Comment: 31 pages, 4 figures, references added, minor change

One-Loop Anomaly Mediated Scalar Masses and (g-2)_mu in Pure Gravity Mediation

We consider the effects of non-universalities among sfermion generations in models of Pure Gravity Mediation (PGM). In PGM models and in many models with strongly stabilized moduli, the gravitino mass may be O(100) TeV, whereas gaugino masses, generated through anomalies at 1-loop, remain relatively light O(1) TeV. In models with scalar mass universality, input scalar masses are generally very heavy (m_0 \simeq m_{3/2}) resulting in a mass spectrum resembling that in split supersymmetry. However, if one adopts a no-scale or partial no-scale structure for the K\"ahler manifold, sfermion masses may vanish at the tree level. It is usually assumed that the leading order anomaly mediated contribution to scalar masses appears at 2-loops. However, there are at least two possible sources for 1-loop scalar masses. These may arise if Pauli-Villars fields are introduced as messengers of supersymmetry breaking. We consider the consequences of a spectrum in which the scalar masses associated with the third generation are heavy (order m_{3/2}) with 1-loop scalar masses for the first two generations. A similar spectrum is expected to arise in GUT models based on E_7/SO(10) where the first two generations of scalars act as pseudo-Nambu-Goldstone bosons. Explicit breaking of this symmetry by the gauge couplings then generates one-loop masses for the first two generations. In particular, we show that it may be possible to reconcile the g_mu - 2 discrepancy with potentially observable scalars and gauginos at the LHC.Comment: 30 pages, 30 figure

Aplikasi Crowdsource Pada Sistem Pencarian Tutor Berbasis Web Dan Android

Nowadays, students are having difficulties looking for tutoringservices. The obstacles are, for example, difficulty to find thetutor, fee that does not fit to the budget, and inflexible schedule.Furthermore, tutors are having difficulties looking for studentswho need his or her service.Due to these reasons, this thesis is intended to create a systemwith web and Android apps that can facilitate tutors and studentsin meeting and holding learning activities. This application can beused by a student looking for an appropriate tutor and also by atutor listing matching students. This application can display themeeting location with the help of Google Map. Based on thequestionnaire result, it can be concluded that most of the usersare satisfied with the application

Non-thermal Gravitino Dark Matter in Gauge Mediation

We show that gravitinos produced by decays of a supersymmetry breaking scalar field (the pseudo-moduli field) can naturally explain the observed abundance of dark matter in a certain class of the gauge mediation models. We study the decay processes as well as cosmological constraints on this scenario in detail, particularly focusing on different behavior of the real and imaginary components of the pseudo-moduli field. Cosmologically viable scenario emerges when the gravitino and the pseudo-moduli masses are O(10-100) MeV and O(100) GeV, respectively.Comment: 32 pages, 10 figure

Patterns of Soft Masses from General Semi-Direct Gauge Mediation

We give a general formulation of semi-direct gauge mediation of supersymmetry breaking where the messengers interact with the hidden sector only through a weakly gauged group. Using this general formulation, we provide an explicit proof that the MSSM gaugino masses are vanishing to leading order in the gauge couplings. On the other hand, the MSSM sfermion masses have, generically, a non-vanishing leading contribution. We discuss how such a mechanism can successfully be combined with other mediation schemes which give tachyonic sfermions, such as sequestered anomaly mediation and some direct gauge mediation models.Comment: 26 pages, 5 figures; v2: refs added; v3: minor corrections, clarifications added, mainly in section

ATLAS Z Excess in Minimal Supersymmetric Standard Model

Recently the ATLAS collaboration reported a 3 sigma excess in the search for the events containing a dilepton pair from a Z boson and large missing transverse energy. Although the excess is not sufficiently significant yet, it is quite tempting to explain this excess by a well-motivated model beyond the standard model. In this paper we study a possibility of the minimal supersymmetric standard model (MSSM) for this excess. Especially, we focus on the MSSM spectrum where the sfermions are heavier than the gauginos and Higgsinos. We show that the excess can be explained by the reasonable MSSM mass spectrum.Comment: 13 pages, 7 figures; published versio

Cosmic Ray Spectra in Nambu-Goldstone Dark Matter Models

We discuss the cosmic ray spectra in annihilating/decaying Nambu-Goldstone dark matter models. The recent observed positron/electron excesses at PAMELA and Fermi experiments are well fitted by the dark matter with a mass of 3TeV for the annihilating model, while with a mass of 6 TeV for the decaying model. We also show that the Nambu-Goldstone dark matter models predict a distinctive gamma-ray spectrum in a certain parameter space.Comment: 16 pages, 4 figure

Origin of light hydrocarbons in recent carbonate oolites in relation to the problem of petroleum genesis in carbonate rocks

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