Localized 4σ4\sigma and 5σ5\sigma Dijet Mass Excesses in ALEPH LEP2 Four-Jet Events

We investigate an excess observed in hadronic events in the archived LEP2 ALEPH data. This excess was observed at preselection level during data-MC comparisons of four-jet events when no search was being performed. The events are clustered into four jets and paired such that the mass difference between the two dijet systems is minimized. The excess occurs in the region M_1+M_2\sim 110\mbox{ GeV}; about half of the excess is concentrated in the region M_1\sim 80\mbox{ GeV}, M_2\sim 25\mbox{ GeV}, with a local significance between $4.7\sigma$ and $5.5\sigma$, depending on assumptions about hadronization uncertainties. The other half of the events are in a broad excess near M_1\sim M_2\sim 55\mbox{ GeV}; these display a local significance of $4.1-4.5\sigma$. We investigate the effects of changing the SM QCD Monte Carlo sample, the jet-clustering algorithm, and the jet rescaling method. We find that the excess is remarkably robust under these changes, and we find no source of systematic uncertainty that can explain the excess. No analogue of the excess is seen at LEP1.Comment: 40 pages, 17 figures. Version published in JHEP. Detector section removed, S/B and SM expectation figure added, expanded discussion of hadronization uncertainties, small changes in systematic errors due to LEP1 data statistics, table added with significance as a function of center-of-mass energy, changes in tex

The Depiction of the Holocaust within the Theme of Escape in Michael Chabon\u27s \u3ci\u3eThe Amazing Adventures of Kavalier & Clay\u3c/i\u3e

Escape sounds like a ram’s horn throughout Michael Chabon’s The Amazing Adventures of Kavalier and Clay, looming large in the lives of his mostly Jewish characters. Only one, Josef Kavalier, is intimately tied to and escapes the Holocaust which destroys his entire family. The horrors of the Holocaust, however, cast a shadow that hovers over nearly every chapter of Chabon’s 636-page novel. For most of the novel’s other characters, intent on plotting their own escapes, the events of the Holocaust remain 4,000 miles away. Americans, Jew and gentile, politically astute and clueless, laborer and capitalist, prefer to maintain a safe distance in mind and in fact. While the Jews of Europe struggle to escape from the ghettos, boxcars, and death in the camps, the Americans of Kavalier & Clay take refuge in glamorous New York City with its big bands, surrealist art and the Golden Age of comic books. Critical opinion about how the Holocaust should be portrayed and to what end, varies widely. The work of Jewish-American fiction authors, such as Michael Chabon, who were not alive when Allied forces liberated the camps, has generated new and thoughtful avenues of criticism. “Will this lead to a trivialization of Holocaust memory,” Christoph Ribbat asks, “Or will these popular genres open the discourse of memory by making it more democratic and more accessible?” (206). At the heart of scholarly work surrounding Chabon’s Pulitzer Prize-winning novel are questions about his depiction of the Holocaust in a work that is not ostensibly about the Holocaust, but one which never escapes it. In this thesis, I explore Chabon’s critique of America’s response to the plight of Europe’s Jews through the exploits of the Escapist, a golemlike comic book character designed to kill Hitler and defeat the Nazis. I examine his purpose in framing his novel within the Golden Age of the comic book industry and the avant-garde cultural life of New York City while the Nazis created a swath of deadly destruction in their march 7 across Europe. Central to my thesis is the theme of escape in the lives of the major characters as well as its role as an established policy in America with regard to the war in Europe. This thesis expands the critical conversation about Chabon’s The Amazing Adventures of Kavalier & Clay, most particularly within the theme of escape, which has not been widely explored. I argue that Kavalier & Clay makes an important contribution to Holocaust literature in its portrayal of America’s effort to escape from an early and effective response to Hitler’s attempt to annihilate the entire Jewish population. I also contend that Kavalier & Clay is a novel that constitutes a thoughtful tribute to Holocaust victims through the frames of a comic book and a hero called the Escapist; it is a call to Americans to consider their responsibility in the face of today’s ongoing worldwide atrocities and civil injustices. Readers of The Amazing Adventures of Kavalier and Clay are encouraged to look more deeply into the Holocaust for signposts and lessons as America continues to face questions of moral and ethical responsibility for its promises of liberty and justice for all. Through his novel, Chabon stimulates a unique and valuable understanding of the Holocaust’s place in post-World War II America

Search for the glueball candidates f0(1500) and fJ(1710) in gamma gamma collisions

Data taken with the ALEPH detector at LEP1 have been used to search for gamma gamma production of the glueball candidates f0(1500) and fJ(1710) via their decay to pi+pi-. No signal is observed and upper limits to the product of gamma gamma width and pi+pi- branching ratio of the f0(1500) and the fJ(1710) have been measured to be Gamma_(gamma gamma -> f0(1500)). BR(f0(1500)->pi+pi-) < 0.31 keV and Gamma_(gamma gamma -> fJ(1710)). BR(fJ(1710)->pi+pi-) < 0.55 keV at 95% confidence level.Comment: 10 pages, 3 figure

Search for supersymmetry with a dominant R-parity violating LQDbar couplings in e+e- collisions at centre-of-mass energies of 130GeV to 172 GeV

A search for pair-production of supersymmetric particles under the assumption that R-parity is violated via a dominant LQDbar coupling has been performed using the data collected by ALEPH at centre-of-mass energies of 130-172 GeV. The observed candidate events in the data are in agreement with the Standard Model expectation. This result is translated into lower limits on the masses of charginos, neutralinos, sleptons, sneutrinos and squarks. For instance, for m_0=500 GeV/c^2 and tan(beta)=sqrt(2) charginos with masses smaller than 81 GeV/c^2 and neutralinos with masses smaller than 29 GeV/c^2 are excluded at the 95% confidence level for any generation structure of the LQDbar coupling.Comment: 32 pages, 30 figure

Measurement of the branching fraction and CP content for the decay B(0) -> D(*+)D(*-)

This is the pre-print version of the Article. The official published version can be accessed from the links below. Copyright @ 2002 APS.We report a measurement of the branching fraction of the decay B0→D*+D*- and of the CP-odd component of its final state using the BABAR detector. With data corresponding to an integrated luminosity of 20.4  fb-1 collected at the Υ(4S) resonance during 1999–2000, we have reconstructed 38 candidate signal events in the mode B0→D*+D*- with an estimated background of 6.2±0.5 events. From these events, we determine the branching fraction to be B(B0→D*+D*-)=[8.3±1.6(stat)±1.2(syst)]×10-4. The measured CP-odd fraction of the final state is 0.22±0.18(stat)±0.03(syst).This work is supported by DOE and NSF (USA), NSERC (Canada), IHEP (China), CEA and CNRS-IN2P3 (France), BMBF (Germany), INFN (Italy), NFR (Norway), MIST (Russia), and PPARC (United Kingdom). Individuals have received support from the A.P. Sloan Foundation, Research Corporation, and Alexander von Humboldt Foundation

Diffractive Dijet Production at sqrt(s)=630 and 1800 GeV at the Fermilab Tevatron

We report a measurement of the diffractive structure function $F_{jj}^D$ of the antiproton obtained from a study of dijet events produced in association with a leading antiproton in $\bar pp$ collisions at $\sqrt s=630$ GeV at the Fermilab Tevatron. The ratio of $F_{jj}^D$ at $\sqrt s=630$ GeV to $F_{jj}^D$ obtained from a similar measurement at $\sqrt s=1800$ GeV is compared with expectations from QCD factorization and with theoretical predictions. We also report a measurement of the $\xi$ ($x$-Pomeron) and $\beta$ ($x$ of parton in Pomeron) dependence of $F_{jj}^D$ at $\sqrt s=1800$ GeV. In the region $0.035<\xi<0.095$, $|t|<1$ GeV$^2$ and $\beta<0.5$, $F_{jj}^D(\beta,\xi)$ is found to be of the form $\beta^{-1.0\pm 0.1} \xi^{-0.9\pm 0.1}$, which obeys $\beta$-$\xi$ factorization.Comment: LaTeX, 9 pages, Submitted to Phys. Rev. Letter

Measurement of the B0-anti-B0-Oscillation Frequency with Inclusive Dilepton Events

The $B^0$-$\bar B^0$ oscillation frequency has been measured with a sample of 23 million \B\bar B pairs collected with the BABAR detector at the PEP-II asymmetric B Factory at SLAC. In this sample, we select events in which both B mesons decay semileptonically and use the charge of the leptons to identify the flavor of each B meson. A simultaneous fit to the decay time difference distributions for opposite- and same-sign dilepton events gives $\Delta m_d = 0.493 \pm 0.012{(stat)}\pm 0.009{(syst)}$ ps$^{-1}$.Comment: 7 pages, 1 figure, submitted to Physical Review Letter

Measurement of the Branching Fraction for B- --> D0 K*-

We present a measurement of the branching fraction for the decay B- --> D0 K*- using a sample of approximately 86 million BBbar pairs collected by the BaBar detector from e+e- collisions near the Y(4S) resonance. The D0 is detected through its decays to K- pi+, K- pi+ pi0 and K- pi+ pi- pi+, and the K*- through its decay to K0S pi-. We measure the branching fraction to be B.F.(B- --> D0 K*-)= (6.3 +/- 0.7(stat.) +/- 0.5(syst.)) x 10^{-4}.Comment: 7 pages, 1 postscript figure, submitted to Phys. Rev. D (Rapid Communications

A Study of Time-Dependent CP-Violating Asymmetries and Flavor Oscillations in Neutral B Decays at the Upsilon(4S)

We present a measurement of time-dependent CP-violating asymmetries in neutral B meson decays collected with the BABAR detector at the PEP-II asymmetric-energy B Factory at the Stanford Linear Accelerator Center. The data sample consists of 29.7 ${\rm fb}^{-1}$ recorded at the $\Upsilon(4S)$ resonance and 3.9 ${\rm fb}^{-1}$ off-resonance. One of the neutral B mesons, which are produced in pairs at the $\Upsilon(4S)$, is fully reconstructed in the CP decay modes $J/\psi K^0_S$, $\psi(2S) K^0_S$, $\chi_{c1} K^0_S$, $J/\psi K^{*0}$ ($K^{*0}\to K^0_S\pi^0$) and $J/\psi K^0_L$, or in flavor-eigenstate modes involving $D^{(*)}\pi/\rho/a_1$ and $J/\psi K^{*0}$ ($K^{*0}\to K^+\pi^-$). The flavor of the other neutral B meson is tagged at the time of its decay, mainly with the charge of identified leptons and kaons. The proper time elapsed between the decays is determined by measuring the distance between the decay vertices. A maximum-likelihood fit to this flavor eigenstate sample finds $\Delta m_d = 0.516\pm 0.016 {\rm (stat)} \pm 0.010 {\rm (syst)} {\rm ps}^{-1}$. The value of the asymmetry amplitude $\sin2\beta$ is determined from a simultaneous maximum-likelihood fit to the time-difference distribution of the flavor-eigenstate sample and about 642 tagged $B^0$ decays in the CP-eigenstate modes. We find $\sin2\beta=0.59\pm 0.14 {\rm (stat)} \pm 0.05 {\rm (syst)}$, demonstrating that CP violation exists in the neutral B meson system. (abridged)Comment: 58 pages, 35 figures, submitted to Physical Review