Electronics calibration board for the ATLAS liquid argon calorimeters Colas, J.; Dumont-Dayot, N.; Marchand, J.F. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
08/2008, Letnik:
593, Številka:
3
Journal Article
Recenzirano
To calibrate the energy response of the ATLAS liquid argon calorimeter, an electronics calibration board has been designed; it delivers a signal whose shape is close to the calorimeter ionization ...current signal with amplitude up to 100
mA in 50
Ω with 16
bit dynamic range. The amplitude of this signal is designed to be uniform over all calorimeters channels, stable in time and with an integral linearity much better that the electronics readout. The various R&D phases and most of the difficulties met are discussed and illustrated by many measurements. The custom design circuits are described and the layout of the ATLAS calibration board presented. The procedure used to qualify the boards is explained and the performance obtained illustrated: a dynamic range up to 3
TeV in three energy scales with an integral linearity better than 0.1% in each of them, a response uniformity better than 0.2% and a stability better than 0.1%. The performance of the board is well within the ATLAS requirements. Finally, in situ measurements done on the ATLAS calorimeter are shown to validate these performances.
In the rabbit, a p59 protein included in the untransformed, non-DNA binding, "8-9S," steroid receptor complexes binds heat shock protein M(r) approximately 90,000 (hsp90). Sequence data Lebeau, M. ...C., Massol, N., Herrick, J., Faber, L. E., Renoir, J. M., Radanyi, C. & Baulieu, E. E. (1992) J. Biol. Chem. 267, 4281-4284 and hydrophobic cluster analysis delineate, from the N terminus, two successive domains closely related to the immunosuppressant FK506 binding immunophilin FKBP (FK506 binding protein), consistent with recent purification of the human p56 immunophilin cognate protein by FK506 affinity chromatography Yem, A. W., Tomasselli, A. G., Heinrikson, R. L., Zurcher-Neely, H., Ruff, V. A., Johnson, R. A. & Deibel, M. R., Jr. (1992) J. Biol. Chem. 267, 2868-2871. The first FKBP-like domain demonstrates all structural characteristics known to be necessary for immunosuppressant binding and for peptidylprolyl cis-trans isomerase (rotamase) activity. Hence, p59 is a "hsp binding immunophilin" (HBI). It is thus speculated that hsp binding immunophilin may help the assembly/disassembly mechanisms involved in steroid receptor trafficking and activity and participate in the poorly understood hsp90 function. ATP/GTP binding likely occurs within the second FKBP-like domain, near the FK506 binding site on the FKBP template. A third domain detected by the hydrophobic cluster analysis method is distantly structurally related to the two first FKBP-like domains and is followed by the C-terminal part of the protein, which contains a calmodulin binding consensus sequence. Hsp binding immunophilin may be involved in a number of immunological, endocrinological, and chaperone-mediated pathways.
The primary sequence of the rabbit liver cDNA coding for protein p59 has been determined. The protein binds to the 90-kDa
heat shock protein (hsp 90) and is associated with it, including when hsp 90 ...participates in hetero-oligomeric complexes of
untransformed mammalian steroid receptors that sediment at 8-10 S. The cloned cDNA codes for an open reading frame of 458
amino acids defining a yet unknown protein. However, 55% amino acid homology to peptidyl-prolyl isomerase is found between
amino acids 41 and 137, suggesting rotamase activity for p59, which speculatively may apply to bound hsp 90 and thus be implied
in the intracellular trafficking of hetero-oligomeric forms of steroid hormone receptors. A polyclonal antibody derived from
the COOH-terminal peptide 441-458 demonstrates a good affinity for rabbit, rat, and human "p59" protein. It interacts with
at least one epitope, available in 8-10 S untransformed steroid receptor complexes and different from that recognized by the
monoclonal antibody KN382/EC-1.
This paper reports inclusive and differential measurements of the $t\bar{t}$ charge asymmetry $A_{\textrm{C}}$ in 20.3 fb$^{-1}$ of $\sqrt{s} = 8$ TeV $pp$ collisions recorded by the ATLAS experiment ...at the Large Hadron Collider at CERN. Three differential measurements are performed as a function of the invariant mass, transverse momentum and longitudinal boost of the $t\bar{t}$ system. The $t\bar{t}$ pairs are selected in the single-lepton channels ($e$ or $\mu$) with at least four jets, and a likelihood fit is used to reconstruct the $t\bar{t}$ event kinematics. A Bayesian unfolding procedure is performed to infer the asymmetry at parton level from the observed data distribution. The inclusive $t\bar{t}$ charge asymmetry is measured to be $A_{\textrm{C}} = 0.009 \pm 0.005$ (stat.$+$syst.). The inclusive and differential measurements are compatible with the values predicted by the Standard Model.
The inclusive jet cross-section is measured in proton-proton collisions at a centre-of-mass energy of 7 TeV using a data set corresponding to an integrated luminosity of 4.5 fb$^{-1}$ collected with ...the ATLAS detector at the Large Hadron Collider in 2011. Jets are identified using the anti-$k_t$ algorithm with radius parameter values of 0.4 and 0.6. The double-differential cross-sections are presented as a function of the jet transverse momentum and the jet rapidity, covering jet transverse momenta from 100 GeV to 2 TeV. Next-to-leading-order QCD calculations corrected for non-perturbative effects and electroweak effects, as well as Monte Carlo simulations with next-to-leading-order matrix elements interfaced to parton showering, are compared to the measured cross-sections. A quantitative comparison of the measured cross-sections to the QCD calculations using several sets of parton distribution functions is performed.
A search is presented for a narrow diboson resonances decaying to $WW$ or $WZ$ in the final state where one $W$ boson decays leptonically (to an electron or a muon plus a neutrino) and the other ...$W/Z$ boson decays hadronically. The analysis is performed using an integrated luminosity of 20.3 fb$^{-1}$ of $pp$ collisions at $\sqrt{s}$ = 8 TeV collected by the ATLAS detector at the LHC. No evidence for resonant diboson production is observed, and resonance masses below 700 GeV and 1490 GeV are excluded at 95% confidence level for the spin-2 Randall-Sundrum bulk graviton $G^*$ with coupling constant of 1.0 and the extended gauge model $W'$ boson respectively.
Studies of the spin and parity quantum numbers of the Higgs boson in the $WW^\ast \to e \nu \mu \nu$ final state are presented, based on proton-proton collision data collected by the ATLAS detector ...at the Large Hadron Collider, corresponding to an integrated luminosity of 20.3 fb$^{-1}$ at a centre-of-mass energy of $\sqrt{s}=8$ TeV. The Standard Model spin-parity $J^{CP} = 0^{++}$ hypothesis is compared with alternative hypotheses for both spin and CP. The case where the observed resonance is a mixture of the Standard-Model-like Higgs boson and CP-even ($J^{CP} = 0^{++}$) or CP-odd ($J^{CP} = 0^{+-}$) Higgs boson in scenarios beyond the Standard Model is also studied. The data are found to be consistent with the Standard Model prediction and limits are placed on alternative spin and CP hypotheses, including CP mixing in different scenarios.
PDF
