Measurement of the Top Quark Mass With 2012 CMS Data

The mass of the top quark was an active topic of research at CMS using 2011 data, and remains so as the 2012 data analysis campaign proceeds. Here we discuss some of the earliest results on the top mass using 2012 sqrt(s) = 8 TeV CMS data, including measurements of the top mass from semileptonic t\bar{t} decays and the lifetime of the B-hadron, as well as a measurement of the top-antitop mass difference.Comment: 4 pages, 8 figures; to appear in Proceedings of 2nd Annual LHC

Exact Half-BPS Black Hole Entropies in CHL Models from Rademacher Series

The microscopic spectrum of half-BPS excitations in toroidally compactified heterotic string theory has been computed exactly through the use of results from analytic number theory. Recently, similar quantities have been understood macroscopically by evaluating the gravitational path integral on the M-theory lift of the AdS2 near-horizon geometry of the corresponding black hole. In this paper, we generalize these results to a subset of the CHL models, which include the standard compactification of IIA on $K3\times T^2$ as a special case. We begin by developing a Rademacher-like expansion for the Fourier coefficients of the partition functions for these theories, which are modular forms for congruence subgroups. We then interpret these results in a macroscopic setting by evaluating the path integral for the reduced-rank $\mathcal{N} = 4$ supergravities described by these CFTs.Comment: 29 pages, no figures. v2: Footnote + citation adde

Measurement of the Top Quark Mass From Dileptonic ttˉt\bar{t} Decays With 2012 CMS Data

We present a measurement of the top quark mass using 19.7 $\pm$ 0.5 fb$^{-1}$ of $\sqrt{s} = 8$ TeV CMS data. In particular, we study dileptonic $t\bar{t}$ decays, in which a top-antitop pair decays to a final state containing two electrons or muons. We use the Analytical Matrix Weighting Technique (AMWT), and have performed the first blind top mass measurement at CMS. The mass of the top quark is measured as $m_t = 172.47 \pm 0.17(\text{stat}) \pm 1.40(\text{syst})$ GeV.Comment: 4 pages, 4 figures, to appear in the Proceedings of the 7th International Workshop on Top Quark Physic

Inclusive Production Through AdS/CFT

It has been shown that AdS/CFT calculations can reproduce certain exclusive 2->2 cross sections in QCD at high energy, both for near-forward and for fixed-angle scattering. In this paper, we extend prior treatments by using AdS/CFT to calculate the inclusive single-particle production cross section in QCD at high center-of-mass energy. We find that conformal invariance in the UV restricts the cross section to have a characteristic power-law falloff in the transverse momentum of the produced particle, with the exponent given by twice the conformal dimension of the produced particle, independent of incoming particle types. We conclude by comparing our findings to recent LHC experimental data from ATLAS and ALICE, and find good agreement.Comment: JHEP version. Discussion, appendix, figures, and tables added. Conclusions and key results unchange

The Transportation Dividend: Transit Investments and the Massachusetts Economy

As home to America's first subway, Boston has been a transit-oriented city for more than a century. In fact, much of our regional economic success is due to the connectivity that a transit system provides. It is no coincidence that the area served by the MBTA houses almost 70 percent of the state's population, offers 74 percent of the jobs, and generates 84 percent of Massachusetts's gross domestic product. The MBTA is the backbone of our economy and any successful strategy for continued growth and prosperity for the region must begin with smart investment in this system.Luckily, the calculus is straightforward as the benefits from our transit system far outweigh the costs we dedicate to support it. A new report from A Better City, made possible through support from both the Barr Foundation and The Boston Foundation, measured the MBTA's performance and economic impact. It found that through travel time and cost savings, vehicular crashes avoided and reduced auto emissions, the MBTA provides an estimated $11.4 billion in value to Greater Boston each year for both transit users and non-users alike. Boston residents experience all of these benefits from the T's annual operating budget of approximately$2 billion.The report also considered the alternative, examining what would it cost if our transit system did not exist. Our economy would require the capital cost of nearly 2,300 additional lane miles of roads and 400,000 more parking spaces. If we needed to build that today, the cost for this vehicular infrastructure would be over $15 billion. The MBTA is a bargain today and for the future

Integrating plant- and animal-based perspectives for more effective restoration of biodiversity

Ecological restoration of modified and degraded landscapes is an important challenge for the 21st century, with potential for major gains in the recovery of biodiversity. However, there is a general lack of agreement between plant- and animal-based approaches to restoration, both in theory and practice. Here, we review these approaches, identify limitations from failing to effectively integrate their different perspectives, and suggest ways to improve outcomes for biodiversity recovery in agricultural landscapes. We highlight the need to strengthen collaboration between plant and animal ecologists, to overcome disciplinary and cultural differences, and to achieve a more unified approach to restoration ecology. Explicit consideration of key ecosystem functions, the need to plan at multiple spatial and temporal scales, and the importance of plant–animal interactions can provide a bridge between plant- and animal-based methods. A systematic approach to restoration planning is critical to achieving effective biodiversity outcomes while meeting long-term social and economic needs