2,654 Matching Results

Search Results

Advanced search parameters have been applied.
in subjects: "Baryons"  
Results: 1 - 24 next
open access

Strange decays of nonstrange baryons

Description: The strong decays of excited nonstrange baryons into the final states {Lambda}K, {Sigma}K, and for the first time into {Lambda}(1405)K, {Lambda}(1520)K, {Sigma}(1385)K, {Lambda}K{sup *}, and {Sigma}K{sup *}, are examined in a relativized quark pair creation model. The wave functions and parameters of the model are fixed by previous calculations of N{pi} and N{pi}{pi}, etc., decays. The results show that it should be possible to discover several new negative parity excited baryons and confirm th… more
Date: April 1, 1998
Creator: Capstick, Simon & Roberts, W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

First charm baryon physics from SELEX(E781)

Description: We present preliminary results on various aspects of charm baryon studies at the 1996-1997 fixed target experiment of Fermilab studying charm produced from incident {Sigma}{sup -}, proton, and {pi}{sub -} beams at 600 GeV. First results include the comparison of hadroproduction asymmetries for {Lambda}{sub c}{sup +} production from the 3 beams as well xF distributions and the first observation of the Cabbibo-suppressed decay {Xi}{sub c}{sup +} {yields} pK{sup -}{pi}{sup +}. The relative branchi… more
Date: April 16, 1999
Creator: Jun, F. G. Garcia and S. Y.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Heavy baryons - Recent and very new results

Description: Recent results on observations, properties and decay modes of the charmed and beauty baryons will be reviewed. Candidates for several new high mass states which include a cleanly-identified daughter {Lambda}{sub c}{sup +} baryon are seen in data from the SELEX experiment at Fermilab. These states are candidates for doubly-charmed baryons: a {Xi}{sub cc}{sup ++} state and a {Xi}{sub cc}{sup +} state. These candidates are more than 5{sigma} signals in each case at masses of 3520 and 3460 MeV resp… more
Date: January 15, 2003
Creator: Cooper, Peter S
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Charm Baryon production and decays in E687

Description: Preliminary analysis of Charm Baryons from the Fermilab high energy photoproduction experiment E687 is presented. The results include the first observation of {Omega}{sub c}{sup 0}{yields}{Omega}{sup {minus}}{pi}{sup +}.
Date: June 1, 1993
Creator: Cheung, H. W. K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Even parity theta-pentaquark and stable strange nuclear matter

Description: The newly discovered exotic {Theta} baryon of mass 1540 MeV (and very small width) truly has a very low mass, if it is a pentaquark system of even parity. A schematic model in which the coherent interaction of u{bar s} and d{bar s} pairs leads to a very large residual (non-confining) attractive interaction is introduced. This collective vibrational model accounts for the mass and small decay width to the KN channel, but yields a significant coupling to the virtual K*N channel. The schematic mod… more
Date: March 2, 2004
Creator: Miller, Gerald A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Photoproduction amplitudes of P(sub)11 and P(sub)33 baryon resonances in the quark model

Description: Predictions are made for the photoproduction amplitudes of low-lying N^(1/2)+ (P(sub)(11)) and delta^(3/2)+ (P(sub)(33)) resonances, using a quark model with relativistic corrections to the transition operator, and mixed nonrelativistic wavefunctions which are correctly orthogonal to the ground states.These amplitudes are also calculated using relativized model wavefunctions. The results for the Roper resonance N(1440) are in marked disagreement with the data.
Date: January 1, 1992
Creator: Capstick, Simon
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Study of Lambda+(c) Cabibbo favored decays containing a Lambda baryon in the final state

Description: Using data from the FOCUS experiment (FNAL-E831), they study the decay of {Lambda}{sub c}{sup +} baryons into final states contain a {Lambda} hyperon. The branching fractions of {Lambda}{sub c}{sup +} into {Lambda}{pi}{sup +}, {Lambda}{pi}{sup +}{pi}{sup +}{pi}{sup -} and {Lambda}{bar K}{sup 0}K{sup +} relative to that into pK{sup -} {pi}{sup +} are measured to be 0.217 {+-} 0.013 {+-} 0.020, 0.508 {+-} 0.024 {+-} 0.024 and 0.142 {+-} 0.018 {+-} 0.022, respectively. New measurements are also re… more
Date: May 1, 2005
Creator: Link, J. M.; Yager, P. M.; /UC, Davis; Anjos, J. C.; Bediaga, I.; Castromonte, C. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

SELEX: Recent Progress in the Analysis of Charm-Strange and Double-Charm Baryons

Description: SELEX (Fermilab Experiment 781) [1] employs beams of {Sigma}{sup -}, {pi}{sup -}, and protons at around 600 GeV/c to study production and decay properties of charmed baryons. It took data in the 1996/7 fixed target run and is currently analyzing those data. Here they focus on recently obtained results concerning the {Omega}{sub c}{sup 0} lifetime and the doubly-charmed baryons {Xi}{sub cc}{sup +} and {Xi}{sub cc}{sup ++}.
Date: February 1, 2007
Creator: Engelfried, Jurgen
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Properties of Heavy B Hadrons

Description: We review recent measurements of heavy B hadron states including masses and lifetimes of the B{sub c}{sup -} meson as well as excited B states (B**, B**{sub s}). We discuss properties of the B{sub s}{sup 0} meson such as lifetime, lifetime difference {Delta}{Lambda}{sub s}/{Lambda}{sub s} and CP violation in B{sub s}{sup 0} {yields} J/{psi}{phi} decays. We also summarize new measurements of the masses and lifetimes of bottom baryons including the {Lambda}{sub b}{sup 0} baryon, the {Sigma}{sub b… more
Date: April 1, 2009
Creator: Paulini, Manfred
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Search for the. Lambda. sub b baryon at CDF

Description: The {Lambda}{sub b} baryon has been observed recently by UA1 through its decay {Lambda}{sub b} {yields} J/{psi}{Lambda}{degrees}. Although CDF finds twice as many J/{psi} and observes {Lambda}{degrees} decays, no evidence for an {Lambda}{sub b} signal is seen. The UA1 data supports a lower than expected production P{sub T} for the {Lambda}{sub b}, and therefore, a lower pion P{sub T}, below the observation threshold of CDF. This result suggests that UA1 and CDF are probably not inconsistent, bu… more
Date: April 1, 1992
Creator: Gauthier, A. (Illinois Univ., Urbana, IL (United States))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Charm Spectroscopy at BaBar

Description: We present a mini-review on charm spectroscopy at the BABAR experiment. We first report on the c{bar s} meson spectrum, and present precise measurements of the D{sub s1}(2536) meson as well as the properties of the many new states discovered since 2003 (D*{sub s0}(2317), D{sub s1}(2460), D*{sub sJ}(2860), and D{sub sJ}(2700) mesons). We then discuss about charmed baryons observed recently in the BABAR experiment: {Omega}{sub c}{sup 0} and {Omega}*{sub c}{sup 0} css baryons, {Lambda}{sub c}(2940… more
Date: December 21, 2007
Creator: Poireau, Vincent
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Observation of the sigma_b baryons at CDF

Description: We present a measurement of four new bottom baryons in proton-antiproton collisions with a center of mass energy of 1.96 TeV. Using 1.1 fb{sup -1} of data collected by the CDF II detector, we observe four {Lambda}{sup 0}{sub b}{pi}{+-} resonances in the fully reconstructed decay mode {Lambda}{sup 0}{sub b} {yields} {Lambda}{sup +}{sub c}{pi}{sup -}, where {Lambda}{sup +}{sub c} {yields} pK{sup -}{pi}{sup +}. The probability for the background to produce a similar or larger signal is less than 8… more
Date: March 1, 2007
Creator: Pursley, Jennifer M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Recent Results on Charm Decays at Radical S Approx 10 GeV

Description: Recent results on decays of charm particles are presented. The CLEO collaboration has measured two body decay modes of D{sub s} involving {eta}, {eta}{sup 1} or {rho}{sup +}, using the new CLEO 2 detector. They also have new measurements of the branching ratios of the D{sup *0} and D{sup *+}. In charm baryon decays, results from CLEO 2 are presented for {Lambda}{sub c}{sup +} {yields} {Sigma}{sup 0}{pi}{sup +}, {Lambda}{sub c}{sup +} {yields} {Lambda}{pi}{sup +}{pi}{sup 0}, and the W-exchange p… more
Date: September 13, 1991
Creator: Procario, M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Search for the {Lambda}{sub b} baryon at CDF

Description: The {Lambda}{sub b} baryon has been observed recently by UA1 through its decay {Lambda}{sub b} {yields} J/{psi}{Lambda}{degrees}. Although CDF finds twice as many J/{psi} and observes {Lambda}{degrees} decays, no evidence for an {Lambda}{sub b} signal is seen. The UA1 data supports a lower than expected production P{sub T} for the {Lambda}{sub b}, and therefore, a lower pion P{sub T}, below the observation threshold of CDF. This result suggests that UA1 and CDF are probably not inconsistent, bu… more
Date: April 1, 1992
Creator: Gauthier, A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

An Alternative View of the Dynamical Origin of the P11 Nucleon Resonances: Results from the Excited Baryon Analysis Center

Description: We present an alternative interpretation for the dynamical origin of the P{sub 11} nucleon resonances, which results from the dynamical coupled-channels analysis at Excited Baryon Analysis Center of Jefferson Lab. The results indicate the crucial role of the multichannel reaction dynamics in determining the N* spectrum. An understanding of the spectrum and structure of the excited nucleon (N*) states is a fundamental challenge in the hadron physics. The N* states, however, couple strongly to th… more
Date: April 1, 2012
Creator: Kamano, Hiroyuki
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Pion-nucleon scattering in P{sub 11} channel and the Roper resonance

Description: The {pi}N scattering in P{sub 11} channel is investigated within the two-channel model of Pearce and Afnan. The model consists of: (1) vertex interactions b {yields} {pi}N, {pi}{nabla} with b denoting either a bare nucleon or a bare Roper state, (2) a background potential {upsilon}{sub {pi}B,{pi}B} with B = N,{nabla}. Assuming that {upsilon}{sub {pi}B,{pi}B} can be phenomenologically parameterized as a separable form and the {pi}N inelasticity can be accounted for by dressing the {nabla} in the… more
Date: March 1996
Creator: Bugaev, K. A.; Yang, Shin Nan & Lee, T. S. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Magnetic moments of the baryons: An experimental review

Description: Measurements of baryon magnetic moments have provided important insights into the composition of baryons as well as important constraints for model builders. These measurements show that a simple quark model describes most of the salient features. However, the significant discrepancies have raised fundamental questions about baryon structure and produced a steady stream of theoretical papers. I would like to briefly review the technology for making these measurements, the current state of the m… more
Date: November 1, 1990
Creator: Lach, J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Study of Heavy-Flavored Particles

Description: This report discusses the following topics: continuum production and decay of {Lambda}{sub c}{sup +} charmed baryon; search for new decay modes and new charmed baryons; baryons from B meson decay; measurement of {bar B}{sup 0} {yields} D*{sup +}{pi}{sup {minus}} branching ratio; determination of {alpha}{sub s}; software implementation for CLEO II physics; the measurement of the magnetic moments of baryons at the Tevatron; research and development toward a 50 picosecond TOF system; time-flight-o… more
Date: January 1, 1991
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Correlated Leading Baryon-antibaryon Production in e+e- to ccbar to Lambda_c+ antiLambda_c- X

Description: We present a study of 649 {+-} 35 e{sup +}e{sup -} {yields} c{bar c} events produced at {radical}s {approx} 10.6 GeV containing both a {Lambda}{sub c}{sup +} baryon and a {bar {Lambda}}{sub c}{sup -} antibaryon. The number observed is roughly four times that expected if the leading charmed hadron types are uncorrelated, confirming an observation by the CLEO Collaboration. We find a 2-jet topology in these events but very few additional baryons, demonstrating that the primary c and {bar c} are p… more
Date: August 22, 2011
Creator: Aubert, B.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E.; Prudent, X. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
Back to Top of Screen