26 research outputs found
After Midnight: Buried Treasure And Social Squabbles In Georgia\u27s Low Country
Readers who expect a Civil War story in Delirium of the Brave will be disappointed. The Civil War is just a gimmick used by William C. Harris, Jr. to set up his saga of several Savannah, Georgia, families from Civil War times till the present. It begins with a prologue in which the Grand Dra...
Magnetic trapping of ultracold neutrons
Three-dimensional magnetic confinement of neutrons is reported. Neutrons are
loaded into an Ioffe-type superconducting magnetic trap through inelastic
scattering of cold neutrons with 4He. Scattered neutrons with sufficiently low
energy and in the appropriate spin state are confined by the magnetic field
until they decay. The electron resulting from neutron decay produces
scintillations in the liquid helium bath that results in a pulse of extreme
ultraviolet light. This light is frequency downconverted to the visible and
detected. Results are presented in which 500 +/- 155 neutrons are magnetically
trapped in each loading cycle, consistent with theoretical predictions. The
lifetime of the observed signal, 660 s +290/-170 s, is consistent with the
neutron beta-decay lifetime.Comment: 17 pages, 18 figures, accepted for publication in Physical Review
A Measurement of the Branching Ratio of
We report on a study of the decay carried out as
a part of the KTeV/E799 experiment at Fermilab. The 1997 data yielded a sample
of 1543 events, including an expected background of events. An
effective form factor was determined from the observed distribution of the
invariant mass. Using this form factor in the calculation of the
detector acceptance, the branching ratio was measured to be .Comment: 5 pages, 4 figure
A New Measurement of the Radiative Ke3 Branching Ratio and Photon Spectrum
We present a preliminary report on a new measurement of the radiative neutral
Ke3 branching ratio and the first study of the photon spectrum in this decay.
We find BR(Ke3g, E*_g>30 GeV, Th*_eg>20 deg)/BR(Ke3) =
0.911+-0.009(stat)+0.021-0.010(syst)%. Our measurement of the spectrum is
consistent with inner bremsstrahlung only as the source of photons at the 2
sigma level.Comment: 5 pages, 4 figures, proceedings paper from Meson 2000, Cracow,
Poland, May 200
Measurements of the rare decay K_{L} -> e^{+} e^{-} e^{+} e^{-}
We observe 441 K_{L} -> e^{+} e^{-} e^{+} e^{-} candidate events with a
background of 4.2 events and measure B(K_{L} -> e^{+} e^{-} e^{+} e^{-}) =
(3.72 \pm 0.18(stat) \pm 0.23(syst)) \times 10^{-8} in the KTeV/E799II
experiment at Fermilab. Using the distribution of the angle between the planes
of the e^{+} e^{-} pairs, we measure the CP parameters beta_{CP} = -0.23 \pm
0.09(stat) \pm 0.02(syst) and gamma_{CP} = -0.09 \pm 0.09(stat) \pm 0.02(syst).
We also present the first detailed study of the e^{+} e^{-} invariant mass
spectrum in this decay mode.Comment: 14 pages, 4 figure
Search for the K(L) --> PI0 PI0 E+ E- Decay in the KTeV Experiment
The recent discovery of a large CP violating asymmetry in K(L) --> PI+ PI- E+
E- mode has prompted us to seach for the associated K(L) --> PI0 PI0 E+ E-
decay mode in the KTeV-E799 experiment at Fermilab. In 2.7E+11 K(L) decays, one
candidate event has been observed with an expected background of 0.3 event,
resulting in an upper limit for the K(L) --> PI0 PI0 E+ E- branching ratio of
6.6E-09 at the 90% confidence level.Comment: To be published in Phys. Rev. Let
Measurements of Direct CP Violation, CPT Symmetry, and Other Parameters in the Neutral Kaon System
We present a series of measurements based on K -> pi+pi- and K -> pi0pi0
decays collected in 1996-1997 by the KTeV experiment (E832) at Fermilab. We
compare these four K -> pipi decay rates to measure the direct CP violation
parameter Re(e'/e) = (20.7 +- 2.8) x 10^-4. We also test CPT symmetry by
measuring the relative phase between the CP violating and CP conserving decay
amplitudes for K->pi+pi- (phi+-) and for K -> pi0pi0 (phi00). We find the
difference between the relative phases to be Delta-phi = phi00 - phi+- = (+0.39
+- 0.50) degrees and the deviation of phi+- from the superweak phase to be
phi+- - phi_SW =(+0.61 +- 1.19) degrees; both results are consistent with CPT
symmetry. In addition, we present new measurements of the KL-KS mass difference
and KS lifetime: Delta-m = (5261 +- 15) x 10^6 hbar/s and tauS = (89.65 +-
0.07) x 10^-12 s.Comment: Submitted to Phys. Rev. D, August 6, 2002; 37 pages, 32 figure
Factors influencing adults’ immunization practices: a pilot survey study of a diverse, urban community in central Ohio
Branching Ratio Measurement of the decay K_L -> e+ e- mu+ mu-
We have collected a 43 event sample of the decay
with negligible backgrounds and measured its branching ratio to be . We see no evidence for CP violation in this
decay. In addition, we set the 90% confidence upper limit on the combined
branching ratios for the lepton flavor violating decays at , assuming a uniform
phase space distribution
First Measurement of Form Factors of the Decay Xi0->Sigma+ e- anti-nu/e
We present the first measurement of the form factor ratios g1/f1 (direct
axial-vector to vector), g2/f1 (second class current) and f2/f1 (weak
magnetism) for the decay Xi0 -> Sigma+ e- anti-nu/e using the KTeV (E799) beam
line and detector at Fermilab. From the Sigma+ polarization measured with the
decay Sigma+ -> p pi0 and the e- - anti-nu/e correlation, we measure g1/f1 to
be 1.32 +0.21-0.17(stat.) +/- 0.05(syst.), assuming the SU(3)f (flavor) values
for g2/f1 and f2/f1. Our results are all consistent with exact SU(3)f symmetry.Comment: Submitted to Physical Review Letters, 5 pages, 4 figure