Tests of a third generation multianode phototube Bonushkin, Y.; Dworkin, L.; Hauser, J. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
11/1996, Letnik:
381, Številka:
2
Journal Article
Recenzirano
We report on results of tests of the 16-channel Hamamatsu R5900-M16 photomultiplier tube for gain uniformity and stability, pixel uniformity, linearity, cross-talk, and quantum efficiency. These ...parameters are essential to our application; i.e., the read out of signals which are generated by the passage of ionizing particles through the scintillating strips of an electromagnetic shower maximum detector and which are carried to the photodetector by optical fibers. In all respects the R5900-M16 tube performance is found to be superior to that of earlier generations of multianode photomultiplier tubes.
Design features and test results of the CMS endcap muon chambers Acosta, D; Apollinari, G; Arisaka, K ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
11/2002, Letnik:
494, Številka:
1
Journal Article
Recenzirano
Presented are the main design features and performance results of the Cathode Strip Chambers for the CMS Endcap Muon system. Although the strips are unusually wide (up to
16
mm
) for the ...cathode-to-anode wire distance of
5
mm
, the six-plane structure of these chambers yields a spatial resolution of about
80
μm
, essentially uniform and independent of the strip width. In addition, the net spatial resolution of about one-tenth of the strip width at the hardware trigger level
(300
ns)
is obtained using a simple network of comparators. Time resolution achieved at the trigger level is
∼4
ns
(rms) that allows unambiguous tagging of bunch crossings which occur every
25
ns
. Aging test results, including those obtained with a recirculating gas system, are discussed; only minor aging affects were observed. The aging studies were performed with large-scale chambers;
700
m
of wire were irradiated for a dose up to
0.4
C/
cm
of the total accumulated charge.
Large CMS cathode strip chambers: design and performance Acosta, D; Apollinari, G; Blomquist, J ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
10/2000, Letnik:
453, Številka:
1
Journal Article
Recenzirano
Presented are the main design features of the large Cathode Strip Chambers (CSCs) for the CMS Endcap Muon System as well as the performance results obtained with the two full-scale 3.4×1.5 m
2 ...six-plane prototypes. The prototype performance was within the baseline requirements: (a) higher than 99% efficiency of muon track finding at the trigger level with more than 92% probability for bunch crossing identification and better than 2
mm spatial resolution, and (b) better than 150
μm spatial resolution in off-line.
We report on a search for direct Kaluza-Klein graviton production in a data sample of 84 pb(-1) of ppmacr; collisions at sqrts=1.8 TeV, recorded by the Collider Detector at Fermilab. We investigate ...the final state of large missing transverse energy and one or two high energy jets. We compare the data with the predictions from a (3+1+n)-dimensional Kaluza-Klein scenario in which gravity becomes strong at the TeV scale. At 95% confidence level (C.L.) for n=2, 4, and 6 we exclude an effective Planck scale below 1.0, 0.77, and 0.71 TeV, respectively.
We present the results of a search for pair production of scalar top quarks (t(1)) in an R-parity violating supersymmetry scenario in 106 pb(-1) of pp collisions at square root of s=1.8 TeV collected ...by the Collider Detector at Fermilab. In this mode each t(1) decays into a tau lepton and a b quark. We search for events with two tau's, one decaying leptonically (e or mu) and one decaying hadronically, and two jets. No candidate events pass our final selection criteria. We set a 95% confidence level lower limit on the t(1) mass at 122 GeV/c(2) for Br(t(1)-->tau b)=1.
We report on a search for a high mass, narrow width particle that decays directly to emu, etau, or microtau. We use approximately 110 pb(-1) of data collected with the Collider Detector at Fermilab ...from 1992 to 1995. No evidence of lepton flavor violating decays is found. Limits are set on the production and decay of sneutrinos with R-parity violating interactions.
We have searched for pair production of the supersymmetric partner of the top quark (stop) in 107 pb(-1) of pp collisions at square root of s=1.8 TeV collected by the Collider Detector at Fermilab ...(CDF). Each stop is assumed to decay into a lepton, bottom quark, and supersymmetric neutrino. Such a scenario would give rise to events with two leptons, two hadronic jets, and a substantial imbalance of transverse energy. No evidence of such a stop signal has been found. We exclude stop masses in the region (80</=m(t)</=135 GeV/c(2)) in the mass plane of stop versus sneutrino.
We present a search for associated production of the Upsilon(1S) and a vector boson in 83 pb(-1) of ppmacr; collisions at sqrts=1.8 TeV collected by the CDF experiment in 1994-1995. We find no ...evidence of the searched signal in the data, and set upper limits to the production cross sections.
We report a search for the production of long-lived charged massive particles in a data sample of 90 pb(-1) of square roots=1.8 TeV pp collisions recorded by the Collider Detector at Fermilab. The ...search uses the muonlike penetration and anomalously high ionization energy loss signature expected for such a particle to discriminate it from backgrounds. The data are found to agree with background expectations, and cross section limits of O(1) pb are derived using two reference models, a stable quark and a stable scalar lepton.
The exclusive gammaE(T) signal has a small standard model cross section and is thus a channel sensitive to new physics. This signature is predicted by models with a superlight gravitino or with large ...extra spatial dimensions. We search for such signals at the Collider Detector at Fermilab, using 87 pb(-1) of data at square root s=1.8 TeV, and extract 95% C.L. limits on these processes. A limit of 221 GeV is set on the scale |F|(1/2) in supersymmetric models. For 4, 6, and 8 extra dimensions, model-dependent limits on the fundamental mass scale M(D) of 0.55, 0.58, and 0.60 TeV, respectively, are found. We also specify a "pseudo-model-independent" method of comparing the results to theoretical predictions.
