Dark Matter in Gauge Mediation from Emergent Supersymmetry

We investigated the viability of neutralino dark matter in the gauge mediation from emergent supersymmetry proposal. In this proposal, supersymmetry is broken at Planck scale and consequently, the gravitino is superheavy and completely decouples from the low energy theory. Squarks and sleptons obtain their soft masses dominantly through gauge mediation with other mechanisms highly suppressed. The lightest supersymmetric partner, in contrast to traditional gauge mediation, is a neutralino which is also a dark matter candidate. By explicit calculation of the low energy spectra, the parameter space was constrained using the WMAP observed relic density of dark matter, LEP2 Higgs mass bounds, collider bounds on supersymmetric partners and exotic B-meson decays. We found that the model has intriguing hybrid features such as a nearly gauge-mediated spectrum (the exception being the superheavy gravitino) but with a dominant mSUGRA-like bino-stau coannihilation channel and at large $\tan \beta$, A-resonance-like annihilation.Comment: 14 pages, 4 figure

Use of personal child health records in the UK: findings from the millennium cohort study.

OBJECTIVES: The personal child health record (PCHR) is a record of a child's growth, development, and uptake of preventive health services, designed to enhance communication between parents and health professionals. We examined its use throughout the United Kingdom with respect to recording children's weight and measures of social disadvantage and infant health. DESIGN: Cross sectional survey within a cohort study. SETTING: UK. PARTICIPANTS: Mothers of 18,503 children born between 2000 and 2002, living in the UK at 9 months of age. MAIN OUTCOME MEASURES: Proportion of mothers able to produce their child's PCHR; proportion of PCHRs consulted containing record of child's last weight; effective use of the PCHR (defined as production, consultation, and child's last weight recorded). RESULTS: In all, 16,917 (93%) mothers produced their child's PCHR and 15,138 (85%) mothers showed effective use of their child's PCHR. Last weight was recorded in 97% of PCHRs consulted. Effective use was less in children previously admitted to hospital, and, in association with factors reflecting social disadvantage, including residence in disadvantaged communities, young maternal age, large family size (four or more children; incidence rate ratio 0.87; 95% confidence interval 0.83 to 0.91), and lone parent status (0.88; 0.86 to 0.91). CONCLUSIONS: Use of the PCHR is lower by women living in disadvantaged circumstances, but overall the record is retained and used by a high proportion of all mothers throughout the UK in their child's first year of life. PCHR use is endorsed in the National Service Framework for Children and has potential benefits which extend beyond the direct care of individual children

Radiative corrections to the semileptonic and hadronic Higgs-boson decays H -> W W/Z Z -> 4 fermions

The radiative corrections of the strong and electroweak interactions are calculated for the Higgs-boson decays H -> WW/ZZ -> 4f with semileptonic or hadronic four-fermion final states in next-to-leading order. This calculation is improved by higher-order corrections originating from heavy-Higgs-boson effects and photonic final-state radiation off charged leptons. The W- and Z-boson resonances are treated within the complex-mass scheme, i.e. without any resonance expansion or on-shell approximation. The calculation essentially follows our previous study of purely leptonic final states. The electroweak corrections are similar for all four-fermion final states; for integrated quantities they amount to some per cent and increase with growing Higgs-boson mass M_H, reaching 7-8% at M_H \sim 500 GeV. For distributions, the corrections are somewhat larger and, in general, distort the shapes. Among the QCD corrections, which include corrections to interference contributions of the Born diagrams, only the corrections to the squared Born diagrams turn out to be relevant. These contributions can be attributed to the gauge-boson decays, i.e. they approximately amount to \alpha_s/\pi for semileptonic final states and 2\alpha_s/\pi for hadronic final states. The discussed corrections have been implemented in the Monte Carlo event generator PROPHECY4F.Comment: 29 pages, LaTeX, 30 postscript figure

Is "just-so" Higgs splitting needed for t-b-\tau Yukawa unified SUSY GUTs?

Recent renormalization group calculations of the sparticle mass spectrum in the Minimal Supersymmetric Standard Model (MSSM) show that t-b-\tau Yukawa coupling unification at M_{\rm GUT} is possible when the mass spectra follow the pattern of a radiatively induced inverted scalar mass hierarchy. The calculation is entirely consistent with expectations from SO(10) SUSY GUT theories, with one exception: it seems to require MSSM Higgs soft term mass splitting at M_{\rm GUT}, dubbed "just-so Higgs splitting" (HS) in the literature, which apparently violates the SO(10) gauge symmetry. Here, we investigate three alternative effects: {\it i}). SO(10) D-term splitting, {\it ii}). inclusion of right hand neutrino in the RG calculation, and {\it iii}). first/third generation scalar mass splitting. By combining all three effects (the DR3 model), we find t-b-\tau Yukawa unification at M_{\rm GUT} can be achieved at the 2.5% level. In the DR3 case, we expect lighter (and possibly detectable) third generation and heavy Higgs scalars than in the model with HS. In addition, the light bottom squark in DR3 should be dominantly a right state, while in the HS model, it is dominantly a left state.Comment: 21 pages with 11 .eps figures; revised version added two reference

Graviton production with 2 jets at the LHC in large extra dimensions

We study Kaluza-Klein (KK) graviton production in the large extra dimensions model via 2 jets plus missing transverse momentum signatures at the LHC. We make predictions for both the signal and the dominant Zjj and Wjj backgrounds, where we introduce missing P_T-dependent jet selection cuts that ensure the smallness of the 2-jet rate over the 1-jet rate. With the same jet selection cuts, the distributions of the two jets and their correlation with the missing transverse momentum provide additional evidence for the production of an invisible massive object.Comment: 8 pages, 10 figures, 1 table; Version to be printed in JHE

Significant association of a M129V independent polymorphism in the 5\prime UTR of the PRNP gene with sporadic Creutzfeldt-Jakob disease in a large German case-control study

Background: A single nucleotide polymorphism (SNP) in the coding region of the prion protein gene (PRNP) at codon 129 has been repeatedly shown to be an associated factor to sporadic Creutzfeldt-Jakob disease (sCJD), but additional major predisposing DNA variants for sCJD are still unknown. Several previous studies focused on the characterisation of polymorphisms in PRNP and the prion-like doppel gene (PRND), generating contradictory results on relatively small sample sets. Thus, extensive studies are required for validation of the polymorphisms in PRNP and PRND.Methods: We evaluated a set of nine SNPs of PRNP and one SNP of PRND in 593 German sCJD patients and 748 German healthy controls. Genotyping was performed using MALDI-TOF mass spectrometry.Results: In addition to PRNP 129, we detected a significant association between sCJD and allele frequencies of six further PRNP SNPs. No significant association of PRND T174M with sCJD was shown. We observed strong linkage disequilibrium within eight adjacent PRNP SNPs, including PRNP 129. However, the association of sCJD with PRNP 1368 and PRNP 34296 appeared to be independent on the genotype of PRNP 129. We additionally identified the most common haplotypes of PRNP to be over-represented or under-represented in our cohort of patients with sCJD.Conclusion: Our study evaluated previous findings of the association of SNPs in the PRNP and PRND genes in the largest cohorts for association study in sCJD to date, and extends previous findings by defining for the first time the haplotypes associated with sCJD in a large population of the German CJD surveillance study

Detecting an invisible Higgs boson at Fermilab Tevatron and CERN LHC

In this paper, we study the observability of an invisible Higgs boson at Fermilab Tevatron and CERN LHC through the production channel q \bar{q} \to Z H \to \ell^+\ell^-+ \ptmiss , where \ptmiss is reconstructed from the $\ell^+\ell^-$ with $\ell=e$ or $\mu$. A new strategy is proposed to eliminate the largest irreducible background, namely $q \bar{q} \to Z(\to \ell^+\ell^-) Z(\to \nu \bar\nu)$. This strategy utilizes the precise measurements of $q \bar{q} \to Z(\to \ell^+\ell^-) Z(\to \ell^+\ell^-)$. For $m_H=120$ GeV and with luminosity $30 fb^{-1}$ at Tevatron, a $5\sigma$ observation of the invisible Higgs boson is possible. For $m_H=114 \sim 140$ GeV with only $10 fb^{-1}$ luminosity at LHC, a discovery signal over $5\sigma$ can be achieved.Comment: 4 Revtex pages including 2 figure