Higgs Mass from D-Terms: a Litmus Test

We explore supersymmetric theories in which the Higgs mass is boosted by the non-decoupling D-terms of an extended $U(1)_X$ gauge symmetry, defined here to be a general linear combination of hypercharge, baryon number, and lepton number. Crucially, the gauge coupling, $g_X$, is bounded from below to accommodate the Higgs mass, while the quarks and leptons are required by gauge invariance to carry non-zero charge under $U(1)_X$. This induces an irreducible rate, $\sigma$BR, for $pp \rightarrow X \rightarrow \ell\ell$ relevant to existing and future resonance searches, and gives rise to higher dimension operators that are stringently constrained by precision electroweak measurements. Combined, these bounds define a maximally allowed region in the space of observables, ($\sigma$BR, $m_X$), outside of which is excluded by naturalness and experimental limits. If natural supersymmetry utilizes non-decoupling D-terms, then the associated $X$ boson can only be observed within this window, providing a model independent `litmus test' for this broad class of scenarios at the LHC. Comparing limits, we find that current LHC results only exclude regions in parameter space which were already disfavored by precision electroweak data.Comment: 7 pages, 9 figure

Molecular Gas in Spiral Galaxies

In this review, I highlight a number of recent surveys of molecular gas in nearby spiral galaxies. Through such surveys, more complete observations of the distribution and kinematics of molecular gas have become available for galaxies with a wider range of properties (e.g., brightness, Hubble type, strength of spiral or bar structure). These studies show the promise of both interferometers and single-dish telescopes in advancing our general understanding of molecular gas in spiral galaxies. In particular, I highlight the contributions of the recent BIMA Survey of Nearby Galaxies (SONG).Comment: 8 pages, 1 figure. To appear in the proceedings of the 4th Cologne-Bonn-Zermatt-Symposium, "The Dense Interstellar Medium in Galaxies", which was held in Zermatt, Switzerland in September 200

A Collective Breaking of R-Parity

Supersymmetric theories with an R-parity generally yield a striking missing energy signature, with cascade decays concluding in a neutralino that escapes the detector. In theories where R-parity is broken the missing energy is replaced with additional jets or leptons, often making traditional search strategies ineffective. Such R-parity violation is very constrained, however, by resulting B and L violating signals, requiring couplings so small that LSPs will decay outside the detector in all but a few scenarios. In theories with additional matter fields, R-parity can be broken collectively, such that R-parity is not broken by any single coupling, but only by an ensemble of couplings. Cascade decays can proceed normally, with each step only sensitive to one or two couplings at a time, but B and L violation requires the full set, yielding a highly suppressed constraint. s-channel production of new scalar states, typically small for standard RPV, can be large when RPV is broken collectively. While missing energy is absent, making these models difficult to discover by traditional SUSY searches, they produce complicated many object resonances (MORes), with many different possible numbers of jets and leptons. We outline a simple model and discuss its discoverability at the LHC.Comment: 28 pages, 10 figure

(De)Constructing a Natural and Flavorful Supersymmetric Standard Model

Using the framework of deconstruction, we construct simple, weakly-coupled supersymmetric models that explain the Standard Model flavor hierarchy and produce a flavorful soft spectrum compatible with precision limits. Electroweak symmetry breaking is fully natural; the mu-term is dynamically generated with no B mu-problem and the Higgs mass is easily raised above LEP limits without reliance on large radiative corrections. These models possess the distinctive spectrum of superpartners characteristic of "effective supersymmetry": the third generation superpartners tend to be light, while the rest of the scalars are heavy.Comment: 36 pages, 4 figures ; v2: references added, expanded discussion of FCNC

Single-Scale Natural SUSY

We consider the prospects for natural SUSY models consistent with current data. Recent constraints make the standard paradigm unnatural so we consider what could be a minimal extension consistent with what we now know. The most promising such scenarios extend the MSSM with new tree-level Higgs interactions that can lift its mass to at least 125 GeV and also allow for flavor-dependent soft terms so that the third generation squarks are lighter than current bounds on the first and second generation squarks. We argue that a common feature of almost all such models is the need for a new scale near 10 TeV, such as a scale of Higgsing or confinement of a new gauge group. We consider the question whether such a model can naturally derive from a single mass scale associated with supersymmetry breaking. Most such models simply postulate new scales, leaving their proximity to the scale of MSSM soft terms a mystery. This coincidence problem may be thought of as a mild tuning, analogous to the usual mu problem. We find that a single mass scale origin is challenging, but suggest that a more natural origin for such a new dynamical scale is the gravitino mass, m_{3/2}, in theories where the MSSM soft terms are a loop factor below m_{3/2}. As an example, we build a variant of the NMSSM where the singlet S is composite, and the strong dynamics leading to compositeness is triggered by masses of order m_{3/2} for some fields. Our focus is the Higgs sector, but our model is compatible with a light stop (with the other generation squarks heavy, or with R-parity violation or another mechanism to hide them from current searches). All the interesting low-energy mass scales, including linear terms for S playing a key role in EWSB, arise dynamically from the single scale m_{3/2}. However, numerical coefficients from RG effects and wavefunction factors in an extra dimension complicate the otherwise simple story.Comment: 32 pages, 3 figures; version accepted by JHE

Investigation of the obscuring circumnuclear torus in the active galaxy Mrk231

Here we report on observations of powerful hydroxyl (OH) line emissions that trace the obscuring material within the circumnuclear environment of the galaxy Markarian 231. The hydroxyl (mega)-maser emission shows the characteristics of a rotating, dusty, molecular torus (or thick disk) located between 30 and 100 pc from the central engine. We now have a clear view of the physical conditions, the kinematics and the spatial structure of this material on intermediate size scales, confirming the main tenets of unification models.Comment: 10 pages, including 3 Figures, published in Nature Vol 421 2003; the published pdf--file and higher quality images are available at http://www.astro.rug.nl/~hrkloeck/np/pubmrk231.htm

Theory of disk accretion onto supermassive black holes

Accretion onto supermassive black holes produces both the dramatic phenomena associated with active galactic nuclei and the underwhelming displays seen in the Galactic Center and most other nearby galaxies. I review selected aspects of the current theoretical understanding of black hole accretion, emphasizing the role of magnetohydrodynamic turbulence and gravitational instabilities in driving the actual accretion and the importance of the efficacy of cooling in determining the structure and observational appearance of the accretion flow. Ongoing investigations into the dynamics of the plunging region, the origin of variability in the accretion process, and the evolution of warped, twisted, or eccentric disks are summarized.Comment: Mostly introductory review, to appear in "Supermassive black holes in the distant Universe", ed. A.J. Barger, Kluwer Academic Publishers, in pres

Incidence, Seasonality and Mortality Associated with Influenza Pneumonia in Thailand: 2005–2008

Data on the incidence, seasonality and mortality associated with influenza in subtropical low and middle income countries are limited. Prospective data from multiple years are needed to develop vaccine policy and treatment guidelines, and improve pandemic preparedness.During January 2005 through December 2008, we used an active, population-based surveillance system to prospectively identify hospitalized pneumonia cases with influenza confirmed by reverse transcriptase–polymerase chain reaction or cell culture in 20 hospitals in two provinces in Thailand. Age-specific incidence was calculated and extrapolated to estimate national annual influenza pneumonia hospital admissions and in-hospital deaths.Influenza was identified in 1,346 (10.4%) of pneumonia patients of all ages, and 10 influenza pneumonia patients died while in the hospital. 702 (52%) influenza pneumonia patients were less than 15 years of age. The average annual incidence of influenza pneumonia was greatest in children less than 5 years of age (236 per 100,000) and in those age 75 or older (375 per 100,000). During 2005, 2006 and 2008 influenza A virus detection among pneumonia cases peaked during June through October. In 2007 a sharp increase was observed during the months of January through April. Influenza B virus infections did not demonstrate a consistent seasonal pattern. Influenza pneumonia incidence was high in 2005, a year when influenza A(H3N2) subtype virus strains predominated, low in 2006 when A(H1N1) viruses were more common, moderate in 2007 when H3N2 and influenza B co-predominated, and high again in 2008 when influenza B viruses were most common. During 2005–2008, influenza pneumonia resulted in an estimated annual average 36,413 hospital admissions and 322 in-hospital pneumonia deaths in Thailand.Influenza virus infection is an important cause of hospitalized pneumonia in Thailand. Young children and the elderly are most affected and in-hospital deaths are more common than previously appreciated. Influenza occurs year-round and tends to follow a bimodal seasonal pattern with substantial variability. The disease burden varies significantly from year to year. Our findings support a recent Thailand Ministry of Public Health (MOPH) decision to extend annual influenza vaccination to older adults and suggest that children should also be targeted for routine vaccination

Growth, cell division and sporulation in mycobacteria

Bacteria have the ability to adapt to different growth conditions and to survive in various environments. They have also the capacity to enter into dormant states and some bacteria form spores when exposed to stresses such as starvation and oxygen deprivation. Sporulation has been demonstrated in a number of different bacteria but Mycobacterium spp. have been considered to be non-sporulating bacteria. We recently provided evidence that Mycobacterium marinum and likely also Mycobacterium bovis bacillus Calmette–Guérin can form spores. Mycobacterial spores were detected in old cultures and our findings suggest that sporulation might be an adaptation of lifestyle for mycobacteria under stress. Here we will discuss our current understanding of growth, cell division, and sporulation in mycobacteria

Natural SUSY Predicts: Higgs Couplings

We study Higgs production and decays in the context of natural SUSY, allowing for an extended Higgs sector to account for a 125 GeV lightest Higgs boson. Under broad assumptions, Higgs observables at the LHC depend on at most four free parameters with restricted numerical ranges. Two parameters suffice to describe MSSM particle loops. The MSSM loop contribution to the diphoton rate is constrained from above by direct stop and chargino searches and by electroweak precision tests. Naturalness, in particular in demanding that rare B decays remain consistent with experiment without fine-tuned cancellations, provides a lower (upper) bound to the stop contribution to the Higgs-gluon coupling (Higgs mass). Two parameters suffice to describe Higgs mixing, even in the presence of loop induced non-holomorphic Yukawa couplings. Generic classes of MSSM extensions, that address the fine-tuning problem, predict sizable modifications to the effective bottom Yukawa, yb. Non-decoupling gauge extensions enhance yb, while a heavy SM singlet reduces yb. A factor of 4-6 enhancement in the diphoton rate at the LHC, compared to the SM prediction, can be accommodated. The ratio of the enhancements in the diphoton vs. the WW and ZZ channels cannot exceed 1.4. The h to bbbar rate in associated production cannot exceed the SM rate by more than 50%.Comment: 31 pages, 11 figure