113 research outputs found
Combined Forward-Backward Asymmetry Measurements in Top-Antitop Quark Production at the Tevatron
The CDF and D0 experiments at the Fermilab Tevatron have measured the asymmetry between yields of forward- and backward-produced top and antitop quarks based on their rapidity difference and the asymmetry between their decay leptons. These measurements use the full data sets collected in proton-antiproton collisions at a center-of-mass energy of TeV. We report the results of combinations of the inclusive asymmetries and their differential dependencies on relevant kinematic quantities. The combined inclusive asymmetry is . The combined inclusive and differential asymmetries are consistent with recent standard model predictions
Search for Heavy Top-like Quarks t' -> Wq Using Lepton Plus Jets Events in 1.96 TeV Proton-Antiproton Collisions
We present the results of a search for pair production of a new heavy
top-like quark t' decaying to a W boson and another quark using the CDF II
detector in Run II of the Tevatron proton-antiproton collider. Using a data
sample corresponding to 760 pb^-1 of integrated luminosity, we fit the observed
spectrum of total transverse energy and reconstructed t' quark mass to a
combination of standard model processes and t' pair production. We see no
evidence for t' pair production, and we infer a lower limit of 256 GeV/c^2 on
the mass of the t' at 95% C.L. assuming standard strong couplings for the t'.Comment: 7 pages, 2 figure
MAGIC and H.E.S.S. detect VHE gamma rays from the blazar OT081 for the first time: a deep multiwavelength study
https://pos.sissa.it/395/815/pdfPublished versio
Broadband Multi-wavelength Properties of M87 during the 2017 Event Horizon Telescope Campaign
Abstract: In 2017, the Event Horizon Telescope (EHT) Collaboration succeeded in capturing the first direct image of the center of the M87 galaxy. The asymmetric ring morphology and size are consistent with theoretical expectations for a weakly accreting supermassive black hole of mass ∼6.5 × 109 M ⊙. The EHTC also partnered with several international facilities in space and on the ground, to arrange an extensive, quasi-simultaneous multi-wavelength campaign. This Letter presents the results and analysis of this campaign, as well as the multi-wavelength data as a legacy data repository. We captured M87 in a historically low state, and the core flux dominates over HST-1 at high energies, making it possible to combine core flux constraints with the more spatially precise very long baseline interferometry data. We present the most complete simultaneous multi-wavelength spectrum of the active nucleus to date, and discuss the complexity and caveats of combining data from different spatial scales into one broadband spectrum. We apply two heuristic, isotropic leptonic single-zone models to provide insight into the basic source properties, but conclude that a structured jet is necessary to explain M87’s spectrum. We can exclude that the simultaneous γ-ray emission is produced via inverse Compton emission in the same region producing the EHT mm-band emission, and further conclude that the γ-rays can only be produced in the inner jets (inward of HST-1) if there are strongly particle-dominated regions. Direct synchrotron emission from accelerated protons and secondaries cannot yet be excluded
Anelastic phenomena and Cr2N precipitation in a high nitrogen austenitic steel
Internal friction (IF) and dynamic modulus measurements on a high nitrogen (0.8 wt%) austenitic
steel in the temperature range from room temperature to 800 °C have been carried out by using a
vibrating reed technique with electrostatic excitation and frequency modulation detection of flexural
vibrations in the frequency range of kHz.
The IF spectrum of the as-prepared material shows a broad peak superimposed to an exponentially
increasing background. The discontinuous precipitation of Cr2N phase changes the characteristics of
the peak. The results have been discussed by considering interstitial-substitutional (i-s) interactions
Generic antiretrovirals for the treatment of HIV: A novel challenge for Western countries?
The introduction of generic antiretroviral medications in developing countries has resulted in significant CD4 cell restoration, HIV viral decline, and a noteworthy reduction in the time to initiation of therapy. Projection models have also predicted significant cost saving associated with the extensive diffusion of generic antiretrovirals in developed countries. However, some uncertainties on generics have recently been raised. These concerns mainly relate to the adequacy of the study design for bioequivalence testing, the potential for uncontrolled switching from one generic to another, and the loss of adherence if patients switched from fixed-dose coformulations to single components in order to incorporate the new generic drugs. In the present review, we deal with current evidence and potential controversial issues regarding generic antiretrovirals and their underlying economic implications and provide some proposals on how to favor the widespread diffusion of generics in HIV medicine. This may be particularly relevant considering that the safe, systematic switch from patented to generic antiretrovirals could potentially guarantee access to therapies for HIV-infected patients worldwide and lead to money savings that would compensate the expenditure increase resulting from new, innovative HIV drugs
SWEATERS Design Report
Scope of this document is to provide the instrument concept report and the rationale of the chosen architecture for the prototype of the Space WEATher Ena Radiation Sensors, namely SWEATERS
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