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Comparison of Tevatron C0 and F0 Lambertson beam impedance

Description: Both the longitudinal and transverse beam impedance measurements for the Tevatron C0 and F0 lambertsons are presented. The C0 lambertsons were designed for circulating beam to travel through the 1 inch high by 6 inch wide field region. In the F0 lambertsons, circulating beam passes through the 2.5 inch high by 4 in ch wide field free region. The more recently designed F0 lambertsons have significantly less impedance than the older C0 lambertsons. Transverse impedance scales as one over the diameter of the aperture cubed. The three C0 style lambertsons were recently removed from the Tevatron. Four of the F0 lambertsons remain. Nine of the F0 style lambertsons are in the Main Injector and three more are required for Numi.
Date: April 11, 2003
Creator: Fellenz, James L Crisp and Brian
Partner: UNT Libraries Government Documents Department

Analytic studies of the long range beam-beam tune shifts and chromaticities

Description: A formula is derived, which allows efficient analytical evaluation of the long range beam-beam tune shifts and chromaticities with amplitude. It assumes that the beams are infinitely short, oppositely charged, and with Gaussian transversal profile. The formula employs an infinite sum with favorable convergence rates, making it well suited especially for the long range case. For a deeper understanding of the beam-beam effects, the structure of the formula was analyzed. It is shown that the tune shifts and chromaticities change sign at certain values of the separation and/or amplitude, and folds in the footprints are predicted. Some special cases were studied in more detail. Applications to the Tevatron are presented, including some proposed compensation schemes.
Date: May 29, 2002
Creator: Erdelyi, Bela & Sen, Tanaji
Partner: UNT Libraries Government Documents Department

Recent results in search for new physics at the Tevatron (Run I)

Description: We present some new results on searches for new physics at the Tevatron Run 1 (1992-1996). The topics covered are searches for R-Parity violating and conserving mSUGRA, large extra dimensions in di-photon and monojet channels, leptoquark in jets + E{sub T} channel, and two model independent searches. All results were finalized during the past year.
Date: January 12, 2004
Creator: Zhou, John
Partner: UNT Libraries Government Documents Department

Impedances of Tevatron separators

Description: The impedances of the Tevatron separators are revisited and are found to be negligibly small in the few hundred MHz region, except for resonances at 22.5 MHz. The later are contributions from the power cables which may drive head-tail instabilities if the bunch is long enough.
Date: May 28, 2003
Creator: Ng, K. Y.
Partner: UNT Libraries Government Documents Department

A search for chargino-neutralino production at the Fermilab Tevatron Collider

Description: We have searched for evidence of supersymmetry with the Collider Detector at Fermilab using trilepton events in p{anti p} collisions at {radical}s = 1.8 TeV. In the Minimal Supersymmetric Standard Model (MSSM), we expect trilepton events from chargino-neutralino ({tilde {xi}}{sup {+-}}{sub 1}{tilde {xi}}{sup 0}{sub 2}) pair production, with subsequent decay into leptons. In all possible combinations of electron and muon channels, we observe no candidate events in 107 pb{sup -1} of data. We present limits on chargino and neutralino production within the framework of a supergravity inspired MSSM: {sigma}{sub {tilde {xi}}{sup {+-}}{sub 1}{tilde {xi}}{sup 0}{sub 2}} {center_dot} BR({tilde {xi}}{sup {+-}}{sub 1}{tilde {xi}}{sup 0}{sub 2} {yields} 3l + X) < 0.34 pb and M{sub {tilde {xi}}{sup {+-}}{sub 1}} > 81.5 GeV/c{sup 2} for tan {beta} = 2, {mu} = -600 GeV/c{sup 2} and M{sub {tilde q}} = M{sub {tilde g}}. We also present limits on a SU(5) x U(1) supergravity model and a 4 and 1/2 parameter Minimal SUGRA model.
Date: December 1, 1997
Creator: Tannenbaum, B.
Partner: UNT Libraries Government Documents Department

Jet Production at the Tevatron

Description: Inclusive jet cross section and dijet angular distribution results from the CDF and D0 collaborations are presented. The possibility that compositeness might be evident at high transverse energies is explored by both experiments. Using the angular distributions, the CDF analysis excludes at the 95% CL regions with {Lambda}{sup +} < 1.8 TeV and {Lambda}{sup -} < 1.6 TeV for a model where all quarks are allowed to be composite objects. The D0 preliminary result excludes at the 95% CL regions with {Lambda}{sup +} < 2.0 TeV for the same model.
Date: June 1, 1997
Creator: Nang, F. & Collaborations, CDF and D0
Partner: UNT Libraries Government Documents Department

Top Quark Mass Measurements from the Tevatron

Description: We review the measurements of the top quark mass by the CDF and D0 collaborations using Run I data in excess of 1.00 pb{sup -1}. The D0 collaboration has recently updated its measurement of the top quark mass in the lepton + jets channel. The world average of the top quark mass from the CDF and D0 measurements in the lepton + jets channel now stands at 175.6 {+-} 5.5 GeV/c{sup 2}.
Date: June 1, 1997
Creator: Raja, R. & Collaborations, CDF and D0
Partner: UNT Libraries Government Documents Department

New phenomena searches at the Tevatron

Description: We present here recent searches at the Tevatron for new phenomena. The superlight gravitino, scalar top and scalar bottom quarks searches are described in the framework of the supersymmetric models. We also discuss the new Tevatron limits on the second and third generations leptoquark masses.
Date: May 24, 1999
Creator: Nomerotski, A.
Partner: UNT Libraries Government Documents Department

Tevatron run-II beam collimation system

Description: Based on realistic Monte-Carlo simulations a two-stage beam collimation system is designed to minimize the beam loss in the Fermilab Tevatron for fixed target and collider Run II. Thin primary collimators are used to increase particle amplitude and their impact parameter on the down-stream secondary collimators. This results in a significant reduction of the total beam loss in the machine, decreases collimator overheating and mitigates requirements to colli-mator alignment. A set of collimators will originally be in-stalled for fixed target operation and for antiprotonbeam re-cycling studies. The collimation system improvement will continue into the collider Run II and intensity upgrade.
Date: April 13, 1999
Creator: al., Michael Church et
Partner: UNT Libraries Government Documents Department

Impedances and collective instabilities of the Tevatron at Run II

Description: The longitudinal and transverse coupling impedances of the Tevatron vacuum chamber are estimated and summed up. The resistive-wall impedances of the beam pipe and the laminations in the Lambertson magnets dominate below {approximately} 50 MHz. Then come the inductive parts of the bellows and BPM`s. The longitudinal and transverse collective instabilities, for both single bunch and multi bunches, are studied using Run II parameters. As expected the transverse coupled-bunch instability driven by the resistive-wall impedance is the most severe collective instability. However, it can be damped by a transverse damper designed for the correction of injection offsets. The power of such a damper has been studied.
Date: September 1, 1998
Creator: Ng, King-Yuen, FERMI
Partner: UNT Libraries Government Documents Department

Heavy flavor physics at the Tevatron

Description: We report on the status of top and b quark physics at the Fermilab Teva-tron collider. In particular, we summarize the knowledge obtained by CDF and D 6 O on the top quark mass and production cross-section. We also present some new interesting results obtained by CDF with the discovery of the Bc meson and a first low statistic measurement of sin(2{beta}) at an hadronic col-lider.
Date: November 1, 1998
Creator: Apollinari, G.
Partner: UNT Libraries Government Documents Department

Top and higgs at the Tevatron: Measurements, searches, prospects

Description: In this paper we summarize the status of Top Quark Physics and of searches for the Standard Model Higgs at the Tevatron. Results from both the CDF and D0 experiments are discussed and the prospects for the upcoming Run 2, in the year 2000, are outlined. Much work has been performed on these topics and due to the nature of these proceedings only a brief explanation can be offered here. For more details the reader should turn to the excellent sources listed in the reference section.
Date: May 11, 1999
Creator: Konigsberg, J.
Partner: UNT Libraries Government Documents Department

Inclusive jets at the Tevatron

Description: Results from CDF and D0 collaborations on the inclusive jet cross sections at 1800 and 630 GeV and strong coupling constant are presented. The statistical uncertainties are significantly reduced relative to the previous results and experimental systematic uncertainties are comparable with the uncertainties in the theoretical predictions. Despite observed discrepancies with theory, which could be accommodated by modifications of parton distribution functions, the inclusive jet cross sections can be described by perturbative Quantum Chromodynamics.
Date: July 2, 1999
Creator: Mesropian, C.
Partner: UNT Libraries Government Documents Department

Searches for new phenomena at the Tevatron: SUSY and technicolor

Description: We present some of the latest updated results on searches for physics beyond the Standard Model at the Tevatron Collider using the full Run 1 data sample of p{anti p} collisions at {radical}s = 1.8 TeV collected with the CDF and D0 detectors. Results are reported relative to searches for squarks and gluinos, scalar top and bottom quarks and superlight gravitino. 95% CL exclusion limits are presented for degenerate states of Technicolor particles {rho}<sub>T</sub> and {omega}<sub>T</sub>.
Date: July 2, 1999
Creator: Rolli, S.
Partner: UNT Libraries Government Documents Department

Accelerator/Experiment Operations - FY 2001 Through FY 2003

Description: This Technical Memorandum (TM) summarizes the accelerator and experiment operations for the period FY 2001 through FY 2003. The plan is to have an annual TM to gather such information in one place. In this case, the information concerns the startup of Run II at the Tevatron Collider and the beginning of the MiniBooNE neutrino experiment. While the focus is on the FY 2003 efforts, this document includes summaries of the earlier years where available for completeness.
Date: February 5, 2004
Creator: al., Jeffrey A. Appel et
Partner: UNT Libraries Government Documents Department

Tevatron stripline turn by turn data and the head-tail instability

Description: Vic Scarpine recently collected turn by turn data from the vertical wideband stripline in the Tevatron during proton injection for store 1841. The data file name is ''PHT004.txt''. The single bunch intensity was roughly 200e9. The chromaticity was set to ''+6'' horizontal and ''-2'' vertical to induce instability. The data shown represents an extreme condition that shortly preceded losses leading to an abort. A Yokogawa DL 7200 oscilloscope was used to measure A-B and A+B simultaneously from the 1 meter long stripline. The scope has an analogue bandwidth of 500MHz with a 2 GHz sample rate. On each of the 2048 turns taken, 200 samples were saved. Vic Scarpine assembled some movie files from the same data that revealed intriguing variations in the A-B signals. The Excel data file contains 2048 turns of A+B followed by 2048 turns of A-B. The 200 samples taken on each turn is placed on one line in the file. Beam was injected at line 14 for A+B and line 2062 for A-B. Eight consecutive turns of data are examined starting at 1490 turns after injection (lines 1504-11 for A+B and 3552-9 for A-B).
Date: December 9, 2002
Creator: Crisp, James L
Partner: UNT Libraries Government Documents Department

Recent results and prospects for high pT physics at D-Zero

Description: The author presents recent results from the D0 experiment using {approx} 50 pb{sup -1} of data recorded at the center of mass energy of 1.96 TeV at the Fermilab Tevatron. In addition, the author summarizes prospects for high p{sub T} physics at the Tevatron as a function of integrated luminosity.
Date: September 11, 2003
Creator: Gerber, Cecilia Elena
Partner: UNT Libraries Government Documents Department

D0 status and first results from Run II

Description: In order to fully exploit the physics potential of the Tevatron Run 2, the D0 detector has been upgraded. Having nearly completed the commissioning phase, the D0 detector is starting to produce its first physics results. An overview of the status of the main subdetectors involved in the upgrade is given, followed by some examples of preliminary physics results already emerging.
Date: January 12, 2004
Creator: Juste, Aurelio
Partner: UNT Libraries Government Documents Department