Radion/Dilaton-Higgs Mixing Phenomenology in Light of the LHC

Motivated by the bulk mixing $\xi R_5 H^{\dagger}H$ between a massive radion and a bulk scalar Higgs in warped extra dimensions, we construct an effective four dimensional action that---via the AdS/CFT correspondence---describes the most general mixing between the only light states in the theory, the dilaton and the Higgs. Due to conformal invariance, once the Higgs scalar is localized in the bulk of the extra-dimension the coupling between the dilaton and the Higgs kinetic term vanishes, implying a suppressed coupling between the dilaton and massive gauge bosons. We comment on the implications of the mixing and couplings to Standard Model particles. Identifying the recently discovered 125 GeV resonance with the lightest Higgs-like mixed state $\phi_{-}$, we study the phenomenology and constraints for the heaviest radion-like state $\phi_{+}$. In particular we find that in the small mixing scenario with a radion-like state $\phi_{+}$ in the mass range [150,250] GeV, the diphoton channel can provide the best chance of discovery at the LHC if the collaborations extend their searches into this energy range.Comment: 28 pages, 6 figures; v2: version published in JHE

CCD QE in the Soft X-ray Range

e2v has previously provided back-illuminated CCDs for several solar observation projects, resulting in a number of key articles on CCD QE in the soft X-ray region. To update these, e2v has arranged for tests on X-ray optimised EMCCDs at a synchrotron. These have shown QE of at least 45% from 40 eV to 2000 eV, with Enhanced process devices having significantly higher QE than Basic process. The measured values were similar to data published from the SDO SXI mission, showing that the e2v process has been stable over many years. The soft X-ray QE measurements show a reasonable fit to the simple layer model for energies > 600 eV. For energies < 100 eV, measurements show slightly lower QE than the model prediction for both Basic and Enhanced processes. For energies 100 eV to 600 eV, measurements show a reasonable fit to the model for the Basic process, but less improvement from the Enhanced process than the model predicts. Comparing the ~80% typical QE for UV-optimised CCDs at 385 nm with the 45% QE measured at 120 eV in this study, there is a discrepancy in QE for two photon energies with the same absorption length measured on CCDs from the same back-thinning process (one type with AR coating, one type without)

Characterization of Chromosomal Inversions Using Anti-Parallel Probes

A method for the characterization of chromosomal inversions using anti-parallel probes is described. Reporter species are attached to oligonucleotide strands designed such that they may hybridize to portions of only one of a pair of single-stranded sister chromatids which may be prepared by the CO-FISH procedure. If an inversion has occurred, these marker probes will be detected on the second sister chromatid at the same location as the inversion on the first chromatid. Further, one or more reporter species are replaced with anti-parallel probes that hybridize at known locations along the second sister chromatid such that the position and size of the inversion may be identified/estimated

The Sugarcane genome sequencing effort: An overview of the strategy, goals and existing data : [Abstract W538]

Sugarcane is a major feedstock used for biofuel production worldwide. Sugarcane cultivars (Saccharum spp) are derived from interspecific hybridization obtained a century ago by crossing Saccharum officinarum (2n=8x=80) and S. spontaneum (2n=5x=40 to 2n=16x=128). The challenge in a sugarcane genome sequencing project is the size (10 Gb) and complexity of its genome structure that is highly polyploid and aneuploid (2n= ca 110 to 120) with a complete set of homo(eo)logous genes predicted to range from 10 to 12 copies (alleles). A initial strategy is to capture much of the gene-rich recombinationally-active euchromatin. The Sugarcane Genome Sequencing Initiative (SUGESI) was envisaged to join efforts to produce a reference sequence of one sugarcane cultivar using a combination of approaches, including BAC sequencing and whole genome shot-gun approaches. Cultivar R570 was chosen since it is the most intensively characterized to date. We expect that around 4-5 thousand BAC sequences can cover the monoploid euchromatic genome of this cultivar. BAC selection is underway using overgo and EST hybridization data. A next step is to sequence cultivars of interest to breeding programs. Under the shot-gun approach gene rich regions are being targeted for genotypes that are parents of mapping populations. This should allow the identification of very large numbers of polymorphic markers that are expected to assist genome assembly. Pilot experiments are underway to define the best technologies for gene-rich region or promoter identification. A database is under construction (http://sugarcanegenome.org). The initiative is led by researchers in Australia, Brazil, China, France, South Africa and United States. (Texte intégral

The Spatial Correlation of Bent-Tail Galaxies and Galaxy Clusters

We have completed a deep radio continuum survey covering 86 square degrees of the Spitzer-South Pole Telescope deep field to test whether bent-tail galaxies are associated with galaxy clusters. We present a new catalogue of 22 bent-tail galaxies and a further 24 candidate bent-tail galaxies. Surprisingly, of the 8 bent-tail galaxies with photometric redshifts, only two are associated with known clusters. While the absence of bent-tail sources in known clusters may be explained by effects such as sensitivity, the absence of known clusters associated with most bent-tail galaxies casts doubt upon current models of bent-tail galaxies.Comment: Accepted by MNRA

Implications of diphoton searches for a Radion in the Bulk-Higgs Scenario

In this work we point out that the apparent diphoton excess initially presented by the ATLAS and CMS collaborations could have originated from a radion in the bulk Higgs scenario within a warped extra dimension. In this scenario the couplings of the radion to massive gauge bosons are suppressed, allowing it to evade existing searches. In the presence of mixing with the Higgs, due to the strong constraints from diboson searches, only points near what we denominate the alignment region were able to explain the diphoton signal and evade other experimental constraints. In light of the new measurements presented at ICHEP 2016 by both LHC collaborations, which do not confirm the initial diphoton excess, we study the current and future collider constraints on a radion within the bulk-Higgs scenario. We find that searches in the diphoton channel provide the most powerful probe of this scenario and already exclude large regions of parameter space, particularly for smaller warp factors. The radion has a sizeable branching ratio into top pairs and this channel may also give competitive constraints in the future. Finally, diHiggs searches can provide a complementary probe in the case of non-zero radion-Higgs mixing but strong alignment.Comment: 20 pages, 12 figures. Several changes including consequences from ICHEP2016. Final version accepted by journa