In-situ Determination of the ATLAS Muon Performance

The ATLAS detector allows for the precise and efficient reconstruction of muons. Muon tracks are reconstructed with 97% efficiency with a momentum resolution of approximately 2-3% over most of the kinematic range and better than 10% for transverse momenta up to 1 TeV and |η| <2.7. We present methods to measure the performance of the muon identification during the operation of the ATLAS detector using muons from Z and J/ψdecays

QCD results using jets and photons in ATLAS

Measurements of jet and photon production performed with data collected during 2010 with the ATLAS detector at the LHC are surveyed. They are compared to leading-order and next-to-leading-order calculations, providing a breadth of tests of QCD at a new energy regime. Agreement is generally found with the most sophisticated calculations, except in regions of phase space where the calculations are expected to reach certain limitations. For those observables for which they are available, next-to-leading-order calculations matched to parton showers are shown to exhibit a large dependence on the choice of parton shower tune, comparable in size to the estimated uncertainties of the perturbative calculations

Study of jet shapes in inclusive jet production in pp collisions at √s=7 TeV using the ATLAS detector

Jet shapes have been measured in inclusive jet production in proton-proton collisions at √s=7  TeV using 3  pb^(-1) of data recorded by the ATLAS experiment at the LHC. Jets are reconstructed using the anti-k_t algorithm with transverse momentum 30  GeV<pT<600  GeV and rapidity in the region |y|<2.8. The data are corrected for detector effects and compared to several leading-order QCD matrix elements plus parton shower Monte Carlo predictions, including different sets of parameters tuned to model fragmentation processes and underlying event contributions in the final state. The measured jets become narrower with increasing jet transverse momentum and the jet shapes present a moderate jet rapidity dependence. Within QCD, the data test a variety of perturbative and nonperturbative effects. In particular, the data show sensitivity to the details of the parton shower, fragmentation, and underlying event models in the Monte Carlo generators. For an appropriate choice of the parameters used in these models, the data are well described

Search for a Standard Model Higgs Boson in the H → ZZ → ℓ^+ℓ^-vv Decay Channel with the ATLAS Detector

A search for a heavy standard model Higgs boson decaying via H→ZZ→ℓ^+ℓ^-νν̅ , where ℓ=e, μ, is presented. It is based on proton-proton collision data at √s=7  TeV, collected by the ATLAS experiment at the LHC in the first half of 2011 and corresponding to an integrated luminosity of 1.04  fb^(-1). The data are compared to the expected standard model backgrounds. The data and the background expectations are found to be in agreement and upper limits are placed on the Higgs boson production cross section over the entire mass window considered; in particular, the production of a standard model Higgs boson is excluded in the region 340<m_H<450  GeV at the 95% confidence level

FORTY YEARS OF BEHAVIOR ANALYSIS IN MEXICO: A REVIEW OF THE MEXICAN JOURNAL OF BEHAVIOR ANALYSIS

The present paper shows a current review of the Mexican Journal of Behavior Analysis (MJBA). The review includes a brief historical summary of the Mexican Society of Behavior Analysis, along with some aspects about the academic and social context of behavior analysis in Mexico which are mentioned in order to understand the origin of MJBA. The paper presents the number of articles published in English and Spanish, an analysis of the articles related to human and non-human behavior, basic and applied research. The paper also reports the first authors’ university affiliation with higher percentage of articles published.Keywords: behavior analysis in Mexico, Mexican Journal of Behavior Analysis, Mexican Society of Behavior Analysi

Fracturas estallido de columna toracolumbar: Evaluación clinicoradiológica y terapéutica de 90 casos

Presentamos un estudio retrospectivo de 90 fracturas toracolumbares tipo estallido con un seguimiento mínimo de 12 meses. Se realizó tratamiento ortopédico en 43 casos y en 47 se indicó una artrodesis instrumentada. Realizamos una evaluación clínico-radiológica en base al dolor residual y evolución del ángulo de cifosis con el objetivo de valorar el tratamiento ortopédico como opción terapéutica y la necesidad de distinguir fracturas estallido con afectación de 2 ó 3 columnas. No apreciamos diferencias estables significativas en el dolor y la lesión de las tres columnas. El aumento de cifosis angular media en las fracturas estallido estable no operadas es de 4.7º y de 5.2º en las fracturas estallido inestables tratadas ortopédicamente. Observamos una alta incidencia de complicaciones relacionadas con la fijación (21%) cuando la fractura asentaba en la charnela y se instrumentaba a un solo nivel. El tratamiento ortopédico es una opción aceptable en las fracturas estallido en pacientes neurológicamente indemnes.Ninety burst fractures of the thoracolumbar spine were retrospectively assessed with a minum follow-up of 12 months. Conservative treatment was indicated in 43 cases, and reduction and surgical stabilization in 47. The aim was to compare the two treatment modalities according to fracture stability. Clinical and radiological evaluation included chronic pain and kyphotic angle progression. No statistical differences were found between stable and unstable fractures as to chronic pain. The kyphotic angle average progression for stable burst fractures was 4.7º and 5.2º for unstable fractures conservatively treated. There was a high rate of complications related to instrumentation (21%) particularly when the fracture was at the thoracolumbar junction and a single level was fixed. The orthopaedic treatment is an acceptable alternative treatment for stable burst fractures without neurological injury

Measurement of the inclusive isolated prompt photon cross section in pp collisions at √s=7 TeV with the ATLAS detector

A measurement of the cross section for the inclusive production of isolated prompt photons in pp collisions at a center-of-mass energy √s=7  TeV is presented. The measurement covers the pseudorapidity ranges |η^γ|<1.37 and 1.52≤|η^γ|<1.81 in the transverse energy range 15≤E_T^γ<100  GeV. The results are based on an integrated luminosity of 880  nb^(-1), collected with the ATLAS detector at the Large Hadron Collider. Photon candidates are identified by combining information from the calorimeters and from the inner tracker. Residual background in the selected sample is estimated from data based on the observed distribution of the transverse isolation energy in a narrow cone around the photon candidate. The results are compared to predictions from next-to-leading-order perturbative QCD calculations

The X-ray spectral properties of the AGN population in the XMM-Newton bright serendipitous survey

We present here a detailed X-ray spectral analysis of the AGN belonging to the XMM-Newton bright survey (XBS) that comprises more than 300 AGN up to redshift ~ 2.4. We performed an X-ray analysis following two different approaches: by analyzing individually each AGN X-ray spectrum and by constructing average spectra for different AGN types. From the individual analysis, we find that there seems to be an anti correlation between the spectral index and the sources' hard X-ray luminosity, such that the average photon index for the higher luminosity sources (> 10E44 erg/s) is significantly flatter than the average for the lower luminosity sources. We also find that the intrinsic column density distribution agrees with AGN unified schemes, although a number of exceptions are found (3% of the whole sample), which are much more common among optically classified type 2 AGN. We also find that the so-called "soft-excess", apart from the intrinsic absorption, constitutes the principal deviation from a power-law shape in AGN X-ray spectra and it clearly displays different characteristics, and likely a different origin, for unabsorbed and absorbed AGN. Regarding the shape of the average spectra, we find that it is best reproduced by a combination of an unabsorbed (absorbed) power law, a narrow Fe Kalpha emission line and a small (large) amount of reflection for unabsorbed (absorbed) sources. We do not significantly detect any relativistic contribution to the line emission and we compute an upper limit for its equivalent width (EW) of 230 eV at the 3 sigma confidence level. Finally, by dividing the type 1 AGN sample into high- and low-luminosity sources, we marginally detect a decrease in the narrow Fe Kalpha line EW and in the amount of reflection as the luminosity increases, the "so-called" Iwasawa-Taniguchi effect.Comment: 42 pages, 15 figures, accepted for publication in Astronomy and Astrophysic

Late differentiation syndrome in acute promyelocytic leukemia: a challenging diagnosis

Detailed knowledge about differentiation syndrome (DS) has remained limited. There are 2 large studies conducted by the Spanish workgroup PETHEMA (Programa Español de Tratamientos en Hematología; Spanish Program on Hematology Treatments) and the European group trial (LPA 96-99 and APL 93) in which the incidence, characteristics, prognostic factors and outcome of patients developing DS are evaluated. Both have described the median time of DS development between 10 and 12 days. The severity of the DS has been evaluated in the study conducted by PETHEMA, and severe DS usually occurs at the beginning of the treatment (median of 6 days), as compared with moderate DS (median of 15 days). We report here in two cases of late severe DS, with late diagnosis due to both time and form of presentation. We discuss the physiopathology, clinical presentation, prophylaxis and treatment of DS

Radial distribution of stars, gas and dust in SINGS galaxies. I. Surface photometry and morphology

We present ultraviolet through far-infrared surface brightness profiles for the 75 galaxies in the Spitzer Infrared Nearby Galaxies Survey (SINGS). The imagery used to measure the profiles includes GALEX UV data, optical images from KPNO, CTIO and SDSS, near-IR data from 2MASS, and mid- and far-infrared images from Spitzer. Along with the radial profiles, we also provide multi-wavelength asymptotic magnitudes and several non-parametric indicators of galaxy morphology: the concentration index (C_42), the asymmetry (A), the Gini coefficient (G) and the normalized second-order moment of the brightest 20% of the galaxy's flux (M_20). Our radial profiles show a wide range of morphologies and multiple components (bulges, exponential disks, inner and outer disk truncations, etc.) that vary not only from galaxy to galaxy but also with wavelength for a given object. In the optical and near-IR, the SINGS galaxies occupy the same regions in the C_42-A-G-M_20 parameter space as other normal galaxies in previous studies. However, they appear much less centrally concentrated, more asymmetric and with larger values of G when viewed in the UV (due to star-forming clumps scattered across the disk) and in the mid-IR (due to the emission of Polycyclic Aromatic Hydrocarbons at 8.0 microns and very hot dust at 24 microns).Comment: 66 pages in preprint format, 14 figures, published in ApJ. The definitive publisher authenticated version is available online at http://dx.doi.org/10.1088/0004-637X/703/2/156