The moment of inertia and the scissors mode of a Bose-condensed gas

Journal of Physics Condensed Matter 14:3 (2002) 343-354

Authors:

OM Maragò, G Hechenblaikner, E Hodby, SA Hopkins, CJ Foot

Abstract:

We relate the frequency of the scissors mode to the moment of inertia of a trapped Bose gas at finite temperature in a semi-classical approximation. We apply these theoretical results to the data obtained in our previous study of the properties of the scissors mode of a trapped Bose-Einstein condensate of 87Rb atoms as a function of the temperature. The frequency shifts that we measured show quenching of the moment of inertia of the Bose gas at temperatures below the transition temperature - the system has a lower moment of inertia than that of a rigid body with the same mass distribution, because of superfluidity.

Search for charmless B --> VV decays.

Phys Rev Lett 88:2 (2002) 021802

Authors:

R Godang, G Bonvicini, D Cinabro, M Dubrovin, S McGee, GJ Zhou, A Bornheim, E Lipeles, SP Pappas, M Schmidtler, A Shapiro, WM Sun, AJ Weinstein, DE Jaffe, G Masek, HP Paar, DM Asner, A Eppich, TS Hill, RJ Morrison, RA Briere, GP Chen, T Ferguson, H Vogel, A Gritsan, JP Alexander, R Baker, C Bebek, BE Berger, K Berkelman, F Blanc, V Boisvert, DG Cassel, PS Drell, JE Duboscq, KM Ecklund, R Ehrlich, AD Foland, P Gaidarev, L Gibbons, B Gittelman, SW Gray, DL Hartill, BK Heltsley, PI Hopman, L Hsu, CD Jones, J Kandaswamy, DL Kreinick, M Lohner, A Magerkurth, TO Meyer, NB Mistry, E Nordberg, M Palmer, JR Patterson, D Peterson, D Riley, A Romano, JG Thayer, D Urner, B Valant-Spaight, G Viehhauser, A Warburton, P Avery, C Prescott, AI Rubiera, H Stoeck, J Yelton, G Brandenburg, A Ershov, DY-J Kim, R Wilson, T Bergfeld, BI Eisenstein, J Ernst, GE Gladding, GD Gollin, RM Hans, E Johnson, I Karliner, MA Marsh, C Plager, C Sedlack, M Selen, JJ Thaler, J Williams, KW Edwards, R Janicek, PM Patel, AJ Sadoff, R Ammar, A Bean, D Besson, X Zhao, S Anderson, VV Frolov, Y Kubota, SJ Lee, R Mahapatra, JJ O'Neill, R Poling, T Riehle, A Smith, CJ Stepaniak, J Urheim, S Ahmed, MS Alam, SB Athar, L Jian, L Ling, M Saleem, S Timm, F Wappler, A Anastassov, E Eckhart, KK Gan, C Gwon, T Hart, K Honscheid, D Hufnagel, H Kagan, R Kass, TK Pedlar, H Schwarthoff, JB Thayer, E von Toerne, MM Zoeller, SJ Richichi, H Severini, P Skubic, A Undrus, V Savinov, S Chen, J Fast, JW Hinson, J Lee, DH Miller, V Pavlunin, EI Shibata, IPJ Shipsey, D Cronin-Hennessy, AL Lyon, EH Thorndike, TE Coan, V Fadeyev, YS Gao, Y Maravin, I Narsky, R Stroynowski, J Ye, T Wlodek, M Artuso, R Ayad, C Boulahouache, K Bukin, E Dambasuren, G Majumder, GC Moneti, R Mountain, S Schuh, T Skwarnicki, S Stone, JC Wang, A Wolf, J Wu, S Kopp, M Kostin, AH Mahmood, SE Csorna, I Danko, KW McLean, Z Xu, CLEO Collaboration

Abstract:

We have studied two-body charmless decays of the B meson into the final states rho(0)rho(0), K(*0)rho(0), K(*0)K(*0), K(*0)K(*0), K(*+)rho(0), K(*+)K(*0), and K(*+)K(*-) using only decay modes with charged daughter particles. Using 9.7x10(6) BB pairs collected with the CLEO detector, we place 90% confidence level upper limits on the branching fractions (1.4-14.1)x10(-5), depending on final state and polarization.

Comparison of the Isolated Direct Photon Cross Sections in $p \bar p$ Collisions at $\sqrt{s}=1.8$ TeV and $\sqrt{s}=0.63$ TeV

ArXiv hep-ex/0201004 (2002)

Authors:

CDF Collaboration, D Acosta

Calculation of mode coupling for quadrupole excitations in a Bose-Einstein condenstate

Physical Review A Atomic Molecular and Optical Physics 65:3 B (2002) 033612/9

Authors:

G Hechenblaikner, SA Morgan, E Hodby, OM Maragò, CJ Foot

Abstract:

A simple model describing the nonlinear coupling of quasiparticle amplitudes of two modes is derived. The model, in particular, can be used to study squeezing effects that are directly related to the matrix element governing the coupling process. This paper demonstrates how to calculate this matrix element analytically and focuses on the quadrupole excitations.

Charged jet evolution and the underlying event in proton-antiproton collisions at 1.8 TeV

Physical Review D Particles Fields Gravitation and Cosmology 65:9 (2002)

Authors:

T Affolder, H Akimoto, A Akopian, MG Albrow, P Amaral, D Amidei, K Anikeev, J Antos, G Apollinari, T Arisawa, A Artikov, T Asakawa, W Ashmanskas, F Azfar, P Azzi-Bacchetta, N Bacchetta, H Bachacou, S Bailey, P Barbaro, A Barbaro-Galtieri, VE Barnes, BA Barnett, S Baroiant, M Barone, G Bauer, F Bedeschi, S Belforte, WH Bell, G Bellettini, J Bellinger, D Benjamin, J Bensinger, A Beretvas, JP Berge, J Berryhill, A Bhatti, M Binkley, D Bisello, M Bishai, RE Blair, C Blocker, K Bloom, B Blumenfeld, SR Blusk, A Bocci, A Bodek, W Bokhari, G Bolla, Y Bonushkin, D Bortoletto, J Boudreau, A Brandl, S van den Brink, C Bromberg, M Brozovic, E Brubaker, N Bruner, E Buckley-Geer, J Budagov, HS Budd, K Burkett, G Busetto, A Byon-Wagner, KL Byrum, S Cabrera, P Calafiura, M Campbell, W Carithers, J Carlson, D Carlsmith, W Caskey, A Castro, D Cauz, A Cerri, AW Chan, PS Chang, PT Chang, J Chapman, C Chen, YC Chen, MT Cheng, M Chertok, G Chiarelli, I Chirikov-Zorin, G Chlachidze, F Chlebana, L Christofek, ML Chu, YS Chung, CI Ciobanu, AG Clark, A Connolly, J Conway, M Cordelli, J Cranshaw, R Cropp, R Culbertson, D Dagenhart, S D’Auria, F DeJongh

Abstract:

The growth and development of “charged particle jets� produced in proton-antiproton collisions at [Formula Presented] are studied over a transverse momentum range from [Formula Presented] [Formula Presented] to [Formula Presented] [Formula Presented] A variety of leading (highest transverse momentum) charged jet observables are compared with the QCD Monte Carlo models HERWIG, ISAJET, and PYTHIA. The models describe fairly well the multiplicity distribution of charged particles within the leading charged jet, the size of the leading charged jet, the radial distribution of charged particles and transverse momentum around the leading charged jet direction, and the momentum distribution of charged particles within the leading charged jet. The direction of the leading “charged particle jet� in each event is used to define three regions of [Formula Presented] space. The “toward� region contains the leading “charged particle jet�, while the “away� region, on the average, contains the away-side jet. The “transverse� region is perpendicular to the plane of the hard [Formula Presented]-to-[Formula Presented] scattering and is very sensitive to the “underlying event� component of the QCD Monte Carlo models. HERWIG, ISAJET, and PYTHIA with their default parameters do not describe correctly all the properties of the “transverse� region. © 2002 The American Physical Society.