3,994 research outputs found
LHCb detector status and commissioning
The LHCb detector status and commissioning is presented.Comment: HCP06 proceedings for reference
Further studies on Bose-Einstein correlations in W-pair decays
Bose-Einstein correlations in W-pair decays are studied using data collected by the ALEPH detector at centre-of-mass energies up to 208 GeV. The analysis presented is based on the comparison of selected events to "mixed" events constructed from the hadronic parts of selected events using the distribution. The data distribution is consistent with predicted when the Bose-Einstein correlations are present only for pions coming from the same W. The JETSET model with the Bose-Einstein correlations between pions from di erent W's is disfavoured
LEP asymmetries and fits of the Standard Model
The lepton and quark asymmetries measured at LEP are presented. The results
of the Standard Model fits to the electoweak data presented at this conference
are given. The top mass obtained from the fit to the LEP data is
GeV; it is when also the
collider, and data are included.Comment: ps file,8 pages, LAPP-EXP-94.0
Virtual effects of light gauginos and higgsinos: a precision electroweak analysis of split supersymmetry
We compute corrections to precision electroweak observables in supersymmetry
in the limit that scalar superpartners are very massive and decoupled. This
leaves charginos and neutralinos and a Standard Model-like Higgs boson as the
only states with unknown mass substantially affecting the analysis. We give
complete formulas for the chargino and neutralino contributions, derive simple
analytic results for the pure gaugino and higgsino cases, and study the general
case. We find that in all circumstances, the precision electroweak fit improves
when the charginos and neutralinos are near the current direct limits. Larger
higgsino and gaugino masses worsen the fit as the theory predictions
asymptotically approach those of the Standard Model. Since the Standard Model
is considered by most to be an adequate fit to the precision electroweak data,
an important corollary to our analysis is that all regions of parameter space
allowed by direct collider constraints are also allowed by precision
electroweak constraints in split supersymmetry.Comment: 22 pages, 5 figures, v2: typos fixed and note adde
Initial-Final-State Interference in the Z line-shape
The uncertainty in the determination of the Z line-shape parameters coming
from the precision of the calculation of the Initial-State Radiation and
Initial--Final-State Interference is 2 10**(-4) for the total cross section
sigma zero(had) at the Z peak, 0.15 MeV for the Z mass M Z, and 0.1 MeV for the
Z width Gamma Z. Corrections to Initial--Final-State Interference beyond
\Order{\alpha^1} are discussed.Comment: 10 pages LaTeX including 2 PostScript figure
Accessory spleen mimicking pancreatic tumour: evaluation by 99mTc-labelled colloid SPECT/CT study. Report of two cases and a review of nuclear medicine methods utility
The accessory spleen is a common congenital anomaly, typically asymptomatic and harmless to the patient. However, in some clinical cases, this anomaly becoÂmes significant as it can be mistaken for a tumour or lymph node and be missed during a therapeutic splenectomy.
There are nuclear medicine modalities which can be applied in the identification and localisation of an accessory spleen. They include scintigraphy with radiolabelled colloids or heat damaged red blood cells, which are trapped in the splenic tissue. Modern techniques, including hybrid imaging, enable simultaneous structure and tracer distribution evaluations. Additionally, radiation-guided surgery can be used in cases where the accessory spleen, which is usually small (not exceeding 1 cm) and difficult to find among other tissues, has to be removed.
In the study, we would like to present 2 cases of patients in which the malignancy had to be excluded for the reason that the multiple accessory spleens were very closely related to the pancreas. There was a lack of certainty in the multi-phase computed tomography (CT) evaluation; however, this situation was clearly resolved by using the 99mTc-stannous colloid single photon emission computed tomography/ CT study. We would also like to briefly analyse the clinical applications of nuclear medicine in case of an accessory spleen
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