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Beauty physics at the ultrahigh energies of the ELOISATRON (Euroasiatic Long Intersecting Superconducting Accelerator Synchrotron)

Description: The potential for experimentally studying B physics at the proposed INFN 100 TeV ELOISATRON (Euroasiatic Long Intersecting Superconducting Accelerator Synchrotron) is compared with possibilities at 40 TeV at the Superconducting Super Collider. The effect of the increase in center of mass energy on the production and decay of B mesons has been investigated, particularly with respect to the accummulation of large samples of B hadron decays necessary for the detection of CP violating effects. 13 refs., 7 figs., 1 tab.
Date: February 1, 1988
Creator: Cox, B.
Partner: UNT Libraries Government Documents Department

Production and decay of heavy top quarks

Description: Experimental evidence indicates that the top quark exists and has a mass between 50 and 200 GeV/c{sup 2}. The decays of a top quark with a mass in this range are studied with emphasis placed on the mass region near the threshold for production of real W bosons. Topics discussed are: (1) possible enhancement of strange quark production when M{sub W} + m{sub s} < m{sub t} < M{sub W} + m{sub b}; (2) exclusive decays of T mesons to B and B{asterisk} mesons using the non-relativistic quark model; (3) polarization of intermediate W's in top quark decay as a source of information on the top quark mass. The production of heavy top quarks in an e{sup +}e{sup {minus}} collider with a center-of-mass energy of 2 TeV is studied. The effective-boson approximation for photons, Z{sup 0}'s and W's is reviewed and an analogous approximation for interfaces between photons and Z{sup 0}'s is developed. The cross sections for top quark pair production from photon-photon, photon-Z{sup 0}, Z{sup 0}Z{sup 0}, and W{sup +}W{sup {minus}} fusion are calculated using the effective-boson approximation. Production of top quarks along with anti-bottom quarks via {gamma}W{sup +} and Z{sup 0}W{sup +} fusion is studied. An exact calculation of {gamma}e{sup +} {yields} {bar {nu}}t{bar b} is made and compared with the effective-W approximation. 31 refs., 46 figs.
Date: August 1, 1989
Creator: Kauffman, R.P.
Partner: UNT Libraries Government Documents Department

CP violation

Description: Predictions for CP violation in the three generation Standard Model are reviewed based on what is known about the Cabibbo-Kobayashi-Maskawa matrix. Application to the K and B meson systems are emphasized. 43 refs., 13 figs.
Date: December 1, 1989
Creator: Gilman, F.J.
Partner: UNT Libraries Government Documents Department

Application of heavy-light methods to B meson physics

Description: The heavy-light method is applied to the study of the B meson spectrum, the pseudoscalar decay constant f{sub B}, the mixing (B) parameter, and exclusive semileptonic B meson decays. Preliminary results are discussed for f{sub B} and the B parameter at {beta} = 5.7 and {kappa} = 0.165 on a 12{sup 3} {times} 24 lattice and at {beta} = 5.9 and {kappa} = 0.158 on a 16{sup 3} {times} 32 lattice. 9 refs., 2 figs., 2 tabs.
Date: December 29, 1989
Creator: Eichten, E.; Hockney, G. & Thacker, H.B.
Partner: UNT Libraries Government Documents Department

Preparing the database for future CP violation measurements with B-mesons at e/sup +/e/sup -/ machines

Description: We consider the contribution of e/sup /plus//e/sup /minus// machines to the measurement of CP violation in the B systems. Energy regions from the GAMMA(4S) to the Z/degree/ are considered, problems and prospects at each energy are reviewed.
Date: April 7, 1988
Creator: Byers, N.; Foley, K.; Goldberg, M.; Mistry, N & Shipsey, I.
Partner: UNT Libraries Government Documents Department

The physics of heavy flavors

Description: We review the physics of heavy quark flavors, including weak decays, onium, tau leptons, mixing, the Kobayashi-Maskawa matrix, and CP violation in B decay. 36 refs., 12 figs.
Date: December 1, 1987
Creator: Gilman, F.J.
Partner: UNT Libraries Government Documents Department

The physics program of a high-luminosity asymmetric B Factory at SLAC

Description: A high-luminosity asymmetric energy B Factory, proposed as an upgrade to the PEP storage ring at SLAC, provides the best opportunity to study CP violation as a means of testing the consistency of the Standard Model. If the phenomenon of CP violation is explained by the Standard Model simply through the non-zero angles and phase of the Kobayashi-Maskawa matrix, then there are precise relations between the K-M parameters and the various measurable CP-violating asymmetries in B meson decay. Should these consistency relations fail, the origin of CP violation must lie outside the Standard Model framework. Our measurements would then lead to the first experiment-driven extensions of the Standard Model. The B Factory will also carry out a varied, high-quality program of studies of other aspects of the physics of b quarks, as well as high-precision measurements in {tau} and charm physics. We describe a detailed series of measurements to be carried out in the first few years at a peak luminosity of 3 {times} 10{sup 33} cm{sup -2}sec{sup -1}, the initial luminosity goal of the B Factory, as well as the program accessible to a larger data sample.
Date: October 1, 1989
Partner: UNT Libraries Government Documents Department

CP violation in B and D decays

Description: Non-leptonic B decays offer the best opportunity to discover the violation of CP invariance outside the neutral K system. Employing the Standard Model one predicts - with reasonable confidence - CP asymmetries of up to 205 (or even more in some cases). The branching ratios for the individual exclusive modes of interest are not expected to exceed the 10/sup -3/ level in most cases; the identification of such decays poses non-trivial problems. It is shown that by summing intelligently over appropriate classes of decays one can greatly enhance statistics without jeopardizing the signal. Data that contain 10/sup 6/ produced B mesons would allow meaningful searches for CP violation. It is noted that ''New Physics'' could lead to CP asymmetries in D/sup 0/ decays of order 1%. Due to higher branching ratios one can search for such effects in samples of 10/sup 6/ produced D mesons. 7 refs.
Date: June 1, 1986
Creator: Bigi, I.I.
Partner: UNT Libraries Government Documents Department

Measurement of the B hadron lifetime

Description: Data from e/sup +/e/sup -/ collisions collected by the MAC detector at the SLAC storage ring PEP with a new vertex chamber having position resolution of 50 ..mu..m have been analyzed with a new method to make a determination of the lifetime of hadrons containing b-quarks. In addition, data collected with MAC before the vertex chamber was installed have been re-analyzed using the new method. The combined result for the B lifetime is tau/sub b/ = (1.16 +- 0.16(stat.) +- 0.07(syst.)ps) x (1 +- 0.15), where the last factor is the scale. 12 refs., 2 figs.
Date: September 1, 1986
Creator: Ash, W.W.; Band, H.R.; Bloom, E.D.; Bosman, M.; Camporesi, T.; Chadwick, G.B. et al.
Partner: UNT Libraries Government Documents Department

Semi-leptonic news

Description: We present our recent results for the semi-leptonic decays K {yields} {pi}e{nu}, D {yields} Ke{nu}, D {yields} {pi}e{nu} and some exploratory data on B {yields} De{nu} and B {yields} {pi}e{nu}. 20 refs., 5 figs., 2 tabs.
Date: January 1, 1989
Creator: Bernard, C.W. (California Univ., Santa Barbara, CA (USA). Inst. for Theoretical Physics); El-Khadra, A.X. & Soni, A. (Brookhaven National Lab., Upton, NY (USA))
Partner: UNT Libraries Government Documents Department

B physics at the Z sup 0 pole

Description: The SLC has been running at SLAC since April, and more than 100 Z{sup 0} events have been reconstructed. Shortly the new European facility at CERN-LEP-will also turn on, and by the end of the year we anticipate that more than 10,000 Z{sup 0} events will have been registered by each of the four LEP detectors. Most of the experimental facilities at these two machines are equipped with excellent particle tracking and identification. Some have close-in tracking devices which will provide unparalleled precision in trajectory reconstruction, and lead to the possibility of identifying a large proportion of the charmed and beauty particles. Not only does the Z{sup 0} pole offer a relatively large production cross section for e{sup +}e{sup {minus}} machines, but a large proportion of the events are b{bar b} pairs. One sees from this figure that a gain of six or more is obtained from running at the Z{sup 0}. An SLC producing 10{sup 5} events per year yields 20,000 b{bar b} events. Similarly, for LEP, over 200,000 b{bar b} events will become available per year. In addition, the planned upgrade for LEP will increase its luminosity by about an order of magnitude, and the SLC will run with polarized electron beams. The physics that may be studies from these event samples fall into two general categories: tests of the Standard Model; and studies of B mesons and B baryons, including lifetimes, mixing, spectroscopy, and CP violation. 8 refs., 8 figs., 1 tab.
Date: October 1, 1989
Creator: Atwood, W.B. & Mours, B.
Partner: UNT Libraries Government Documents Department

Mechanical and thermal behavior of a prototype support structure for a large silicon vertex detector (BCD)

Description: The Bottom Collider Detector (BCD) has been proposed as a device to study large numbers of events containing B mesons. To identify secondary vertices in hadronic events it will employ the most ambitious silicon strip tracking detector proposed to-date. This report will discuss results from measurements on a first mechanical/thermal model of the vertex detector support structure. The model that was built and used for the studies described here is made of brass. Brass was used because it is readily available and easily assembled by soft soldering, and, for appropriate thicknesses, it will behave similarly to the beryllium that will be used in the actual detector. The trough was built to full scale with the reinforcement webbing and the cooling channels in place. There were no detector modules in place. We plan, however, to install modules in the trough in the future. The purpose of the model was to address two concerns that have arisen about the proposed structure of the detector. The first is whether or not the trough will be stable enough. The trough must be very light in weight yet have a high degree of rigidity. Because of the 3m length of the detector there is question as to the stiffness of the proposed trough. The main concern is that there will sagging or movement of the trough in the middle region. The second problem is the heat load. There will be a great deal of heat generated by the electronics attached to the detector modules. So the question arises as to whether or not the silicon detectors can be kept cool enough so that when the actual experiment is run the readings will be valid. The heat may also induce motion by differential expansion of support components. 26 figs.
Date: August 23, 1989
Creator: Mulderink, H.; Michels, N.; Joestlein, H. (La Grange High School, IL (USA); Apple Valley High School, Rosemont, MN (USA) & Fermi National Accelerator Lab., Batavia, IL (USA))
Partner: UNT Libraries Government Documents Department

Heavy quarks and CP: Moriond 1985

Description: The presentations at the Fifth Moriond Workshop on Heavy Quarks, Flavor Mixing, and CP Violation (La Plagne, France, January 13-19, 1985) are summarized. The following topics are reviewed. What's New (beyond the top, top quarks, bottom quarks, charm quarks, strange quarks, and others); why is all this being done (strong interactions and hadron structure, and electroweak properties); and what next (facilities and can one see CP violation in the B-anti B system). 64 refs., 10 figs.
Date: March 1, 1985
Creator: Bjorken, J.D.
Partner: UNT Libraries Government Documents Department

Rare B decays and CP violation

Description: We review the physics motivation for studying rare B decays and the increasing possibility that cP violation can be experimentally observed in the B meson system. 29 refs., 3 figs.
Date: November 1, 1987
Creator: Gilman, F.J.
Partner: UNT Libraries Government Documents Department

Toponium and two-Higgs models

Description: Bounds from B/sup 0/ - anti B/sup 0/ mixing on charged-Higgs-boson masses and couplings in two-Higgs-doublet models are presented. These bounds are comparable to those obtained, with additional assumptions, from the neutral-K-system. The effects of the neutral Higgs bosons of these models on the spectrum and wave function of toponium are discussed. These effects could, in the future, lead to limits on, or the discovery of, these Higgs bosons. 8 refs., 3 figs.
Date: April 1, 1986
Creator: Franzini, P.J.
Partner: UNT Libraries Government Documents Department

Weak interactions at the SSC

Description: Prospects for the study of standard model weak interactions at the SSC are reviewed, with emphasis on the unique capability of the SSC to study the mechanism of electroweak symmetry breaking whether the associated new quanta are at the TeV scale or higher. Symmetry breaking by the minimal Higgs mechanism and by related strong interaction dynamical variants is summarized. A set of measurements is outlined that would calibrate the proton structure functions and the backgrounds to new physics. The ability to measure the three weak gauge boson vertex is found to complement LEP II, with measurements extending to larger Q/sup 2/ at a comparable statistical level in detectable decays. B factory physics is briefly reviewed as one example of a possible broad program of high statistics studies of sub-TeV scale phenomena. The largest section of the talk is devoted to the possible manifestations of symmetry breaking in the WW and ZZ production cross sections. Some new results are presented bearing on the ability to detect high mass WW and ZZ pairs. The principal conclusion is that although nonstandard model scenarios are typically more forgiving, the capability to study symmetry breaking in the standard model (and in related strong interaction dynamical variants) requires achieving the SSC design goals of ..sqrt.. s,L = 40Tev, 10/sup 33/cm/sup -2/sec/sup -1/. 28 refs., 5 figs.
Date: March 1, 1986
Creator: Chanowitz, M.S.
Partner: UNT Libraries Government Documents Department

Design and construction of a Vertex Chamber and measurement of the average B-Hadron lifetime

Description: Four parameters describe the mixing of the three quark generations in the Standard Model of the weak charged current interaction. These four parameters are experimental inputs to the model. A measurement of the mean lifetime of hadrons containing b-quarks, or B-Hadrons, constrains the magnitudes of two of these parameters. Measurement of the B-Hadron lifetime requires a device that can measure the locations of the stable particles that result from B-Hadron decay. This device must function reliably in an inaccessible location, and survive high radiation levels. We describe the design and construction of such a device, a gaseous drift chamber. Tubes of 6.9 mm diameter, having aluminized mylar walls of 100 ..mu..m thickness are utilized in this Vertex Chamber. It achieves a spatial resolution of 45 ..mu..m, and a resolution in extrapolation to the B-Hadron decay location of 87 ..mu..m. Its inner layer is 4.6 cm from e/sup +/e/sup -/ colliding beams. The Vertex Chamber is situated within the MAC detector at PEP. We have analyzed botht he 94 pb/sup -1/ of integrated luminosity accumulated at ..sqrt..s = 29 GeV with the Vertex Chamber in place as well as the 210 pb/sup -1/ accumulated previously. We require a lepton with large momentum transverse to the event thrust axis to obtain a sample of events enriched in B-Hadron decays. The distribution of signed impact parameters of all tracks in these events is used to measure the B-Hadron flight distance, and hence lifetime. 106 refs., 79 figs., 20 tabs.
Date: October 1, 1987
Creator: Nelson, H.N.
Partner: UNT Libraries Government Documents Department

B/sup 0/-anti B/sup 0/ mixing: A theoretical evaluation after ARGUS

Description: After an introduction into the phenomenology of B/sup 0/ -anti B/sup 0/ mixing is given, a rather detailed is presented on the theoretical concepts that are involved. An attempt is made to elucidate the discrepancy between different theoretical claims. CP violtion is touched only very briefly.
Date: January 1, 1988
Creator: Bigi, I.
Partner: UNT Libraries Government Documents Department

Predictions for CP violation

Description: Predictions for CP violation in the three-generation Standard Model are reviewed, especially as they pertain to the K and B meson systems. 39 refs., 19 figs.
Date: August 1, 1989
Creator: Gilman, F.J.
Partner: UNT Libraries Government Documents Department

Kaon decays

Description: A survey of rare and not so rare kaon decays is presented. The role of such decays both in testing the standard model and searching for new physics'' is discussed. 37 refs., 2 tabs.
Date: January 1, 1989
Creator: Marciano, W.J. (Brookhaven National Lab., Upton, NY (USA))
Partner: UNT Libraries Government Documents Department

General properties of an asymmetric B-factory lattice

Description: The type of collider considered for the production of B mesons consists of two rings in which unequal energy beams circulate. Criteria based on the beam-beam interaction are formulated and it is shown that they are consistent with lattices in which the synchrotron radiation occurs in the bending magnets only. However, the requirements imposed on the low energy ring dipole field and RF power may require the addition of horizontal wigglers in zero dispersion sections to control the damping time and of vertical wigglers in finite dispersion regions to adjust the shape of the beam at the crossing point. 9 refs., 1 fig.
Date: August 1, 1989
Creator: Autin, B.
Partner: UNT Libraries Government Documents Department

Getting maximum information from incomplete data on B yields charmonium-K sub S decays

Description: Tests of CP violation using B decays into CP eigenstates can be improved by using events normally rejected because of incomplete information. A search for lepton asymmetry in decays {Upsilon}(4S) {yields} B + {bar B} {yields} (K{sub S} + J/{psi}) + (lepton {sup {plus minus}} + X) can be improved by including other (c{bar c})K{sub S} events where the (c{bar c}) pair is not bound in a J/{psi} but in some other state like {psi}{prime} or {eta}{sub c} and where the lepton asymmetry is predicted to be the same as for (K{sub S} + J/{psi}), other (c{bar c})K{sub S} events which are not fully reconstructed and (c{bar c})K{sub L} events where the K{sub L} pair is not detected and which are predicted to have the opposite lepton asymmetry from corresponding K{sub S} events. The information from these additional events can give improved statistics if suitable cuts can be found to improve signal/noise. The opposite asymmetry predicted for K{sub L} events can test spurious lepton asymmetries due to systematic errors. 3 refs.
Date: September 18, 1989
Creator: Lipkin, H.J.
Partner: UNT Libraries Government Documents Department