15797229
Self-tuning of the cosmological constant and Einstein Gravity on the brane
We show that a self-tuning mechanism of the cosmological constant could work in 5D non-compact space-time. The standard model matter fields live only on the 4D brane. The change of vacuum energy on the brane just gives rise to dynamical shifts of the profiles of the background metric and a bulk scalar field in the extra dimension, keeping 4D space-time flat. To obtain the Newtonian potential on the brane, we introduce an additional brane-localized 4D Einstein-Hilbert term.
15739165
SO(10)-like Superstring Standard Model with R-parity from the Heterotic String
We construct a supersymmetric standard model in the context of the Z_{12-I} orbifold compactification of the E_8 x E_8' heterotic string theory. The gauge group is SU(3)_c x SU(2)_L x U(1)_Y x U(1)^4 x [SO(10) x U(1)^3]' with sin^2\theta_W = 3/8. We obtain three families of SO(10) spinor-like chiral matter states, and Higgs doublets. All other extra states are exactly vector-like under the standard model gauge symmetry. There are numerous standard model singlets, many of which get VEVs such that only the standard model gauge symmetry survives and desired Yukawa couplings can be generated at lower energies. In particular, all vector-like exotic states achieve superheavy masses and the R-parity can be preserved.
119316975
GMSB at a stable vacuum and MSSM without exotics from heterotic string
Abstract We show that it is possible to introduce the confining hidden sector gauge group SU ( 5 ) ′ with the chiral matter 10 0 ′ plus 5 ¯ 0 ′ , which are neutral under the standard model gauge group, toward a gauge mediated supersymmetry breaking (GMSB) in a Z 12 − I orbifold compactification of E 8 × E 8 ′ heterotic string. Three families of MSSM result without exotics. We also find a desirable matter parity P (or R-parity) assignment. We note that this model contains the spectrum of the Lee–Weinberg model which has a nice solution of the μ problem.
18138135
Neutrino masses from discrete gauge symmetries
Abstract We investigate a model with an extra Z 2 gauge symmetry in the Standard Model. The symmetry gives a structure to the mass matrix for the neutrinos. With two extra Higgs singlets and two extra singlet right-handed neutrinos we can build a model that fits the requirements of the MSW solution of the Solar neutrino problem. With a third singlet right-handed neutrino it is also possible to have a 10 eV neutrino.
14574575
Effective Gauss-Bonnet interaction in Randall-Sundrum compactification
The effective gravitational interaction below the Planck scale in the Randall-Sundrum world is shown to be the Gauss-Bonnet term. In this theory we find that there exists another static solution with a positive bulk cosmological constant. Also, there exist solutions for a positive visible sector cosmological constant, which is needed for a later Friedmann-Robertson-Walker universe.
119883211
Conflicts between B-violating phenomena in supergravity models
Abstract We show that there is an incompatibility between matter stability and cosmological baryon production in standard N = 1 supergravity models. This discrepancy emerges from the bound on the reheating temperature T rh ⩽ 10 10 GeV which comes from the restriction on the gravitino decay after inflation. Some weird possibilities to bypass the controversy are also analyzed.
118189799
The millimeter-wave bolometric interferometer (MBI) for observing the cosmic microwave background polarization
119259465
‘Stop’ that ambulance! New physics at the LHC?
A bstractA number of LHC searches now display intriguing excesses. Most prominently, the measurement of the W+W− cross-section has been consistently ∼ 20% higher than the theoretical prediction across both ATLAS and CMS for both 7 and 8 TeV runs. More recently, supersymmetric searches for final states containing two or three leptons have also seen more events than predicted in certain signal regions. We show that a supersymmetric model containing a light stop, winos and binos can consistently match the data. We perform a fit to all measurements and searches that may be sensitive to our model and find a reduction in the log-likelihood of 15.4 compared to the Standard Model which corresponds to 3.5-σ once the extra degrees of freedom in the fit are considered.
10579423
Pileup subtraction for jet shapes.
Jets in high energy hadronic collisions often contain the fingerprints of the particles that produced them. Those fingerprints, and thus the nature of the particles that produced the jets, can be read off with the help of quantities known as jet shapes. Jet shapes are, however, severely affected by pileup, the accumulation in the detector of the residues of the many simultaneous collisions taking place in the Large Hadron Collider (LHC). We introduce a method to correct for pileup effects in jet shapes. Relative to earlier, limited approaches, the key advance resides in its full generality, achieved through a numerical determination, for each jet, of a given shape's susceptibility to pileup. The method rescues the possibility of using jet shapes in the high pileup environment of current and future LHC running, as we show with examples of quark-gluon discrimination and top tagging.
119291744
Neutrino masses and mixings in the baryon triality constrained minimal supersymmetric standard model
We discuss how the experimental neutrino oscillation data can be realized in the framework of the baryon triality ($B_3$) constrained supersymmetric Standard Model (cSSM). We show how to obtain phenomenologically viable solutions, which are compatible with the recent WMAP observations. We present results for the hierarchical, inverted and degenerate cases which illustrate the possible size and structure of the lepton number violating couplings. We work with a new, as yet unpublished version of SOFTSUSY, where we implemented full one--loop neutrino masses. Finally, we shortly discuss some phenomenological implications at the LHC.
13595363
CheckMATE: Confronting your favourite new physics model with LHC data
Abstract In the first three years of running, the LHC has delivered a wealth of new data that is now being analysed. With over 20 fb−1 of integrated luminosity, both ATLAS and CMS have performed many searches for new physics that theorists are eager to test their model against. However, tuning the detector simulations, understanding the particular analysis details and interpreting the results can be a tedious task. Check mate (Check Models At Terascale Energies) is a program package which accepts simulated event files in many formats for any model. The program then determines whether the model is excluded or not at 95% C.L. by comparing to many recent experimental analyses. Furthermore the program can calculate confidence limits and provide detailed information about signal regions of interest. It is simple to use and the program structure allows for easy extensions to upcoming LHC results in the future. Program summary Program title: CheckMATE Catalogue identifier: AEUT_v1_0 Program summary URL: http://cpc.cs.qub.ac.uk/summaries/AEUT_v1_0.html Program obtainable from: CPC Program Library, Queen’s University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 179960 No. of bytes in distributed program, including test data, etc.: 6089336 Distribution format: tar.gz Programming language: C++, Python. Computer: PC, Mac. Operating system: Linux, Mac OS. RAM: Bytes Classification: 11.9. External routines: ROOT, Python, Delphes (included with the distribution) Nature of problem: The LHC has delivered a wealth of new data that is now being analysed. Both ATLAS and CMS have performed many searches for new physics that theorists are eager to test their model against. However, tuning the detector simulations, understanding the particular analysis details and interpreting the results can be a tedious and repetitive task. Solution method: CheckMATE is a program package which accepts simulated event files in many formats for any model. The program then determines whether the model is excluded or not at 95% C.L. by comparing to many recent experimental analyses. Furthermore the program can calculate confidence limits and provide detailed information about signal regions of interest. It is simple to use and the program structure allows for easy extensions to upcoming LHC results in the future. Restrictions: Only a subset of available experimental results have been implemented. Additional comments: Checkmate is built upon the tools and hard work of many people. If Checkmate is used in your publication it is extremely important that all of the following citations are included, • Delphes 3 [1]. • FastJet [2, 3]. • Anti-kt jet algorithm [4]. • C L s prescription [5]. • In analyses that use the MT2 kinematical discriminant we use the Oxbridge Kinetics Library [6, 7] and the algorithm developed by Cheng and Han [8]. • All experimental analyses that were used to set limits in the study. • The Monte Carlo event generator that was used. Running time: The running time scales about linearly with the number of input events provided by the user. The detector simulation/analysis of 20000 events needs about 50 s/1 s for a single core calculation on an Intel Core i5-3470 with 3.2 GHz and 8 GB RAM. References: [1] J. de Favereau, C. Delaere, P. Demin, A. Giammanco, V. Lematre, et al., DELPHES 3, A modular framework for fast simulation of a generic collider experiment arXiv:1307.6346 . [2] M. Cacciari, G.P. Salam, G. Soyez, FastJet User Manual, Eur. Phys. J. C72 (2012) 1896. arXiv:1111.6097 , http://dx.doi.org/10.1140/epjc/s10052-012-1896-2 . [3] M. Cacciari, G.P. Salam, Dispelling the N3 myth for the k t jet-finder, Phys. Lett. B641 (2006) 57–61. arXiv:hep-ph/0512210 , http://dx.doi.org/10.1016/j.physletb.2006.08.037 . [4] M. Cacciari, G.P. Salam, G. Soyez, The Anti-k(t) jet clustering algorithm, JHEP 0804 (2008) 063. arXiv:0802.1189 , http://dx.doi.org/10.1088/1126-6708/2008/04/063 . [5] A.L. Read, Presentation of search results: the cl’s technique, Journal of Physics G: Nuclear and Particle Physics 28 (10) (2002) 2693. URL http://stacks.iop.org/0954-3899/28/i=10/a=313 [6] C. Lester, D. Summers, Measuring masses of semiinvisibly decaying particles pair produced at hadron colliders, Phys. Lett. B463 (1999) 99–103. arXiv:hep-ph/9906349 , http://dx.doi.org/10.1016/S0370-2693(99)00945-4 . [7] A. Barr, C. Lester, P. Stephens, m(T2): The Truth behind the glamour, J. Phys. G29 (2003) 2343–2363. arXiv:hep-ph/0304226 , http://dx.doi.org/10.1088/0954-3899/29/10/304 . [8] H.-C. Cheng, Z. Han, Minimal Kinematic Constraints and m(T2), JHEP 0812 (2008) 063. arXiv:0810.5178 , http://dx.doi.org/10.1088/1126-6708/2008/12/063 .