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4.
Phys Rev Lett ; 100(6): 062006, 2008 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-18352462

RESUMO

We propose a simple explanation for the increase of approximately 3 MeV/c;{2} in the mass value of the X(3872) obtained from D(*0)D(0) decay relative to that obtained from decay to J/psipi(+)pi(-). If the total width of the X(3872) is 2-3 MeV, the peak position in the D(*0)D(0) invariant mass distribution is sensitive to the final state orbital angular momentum because of the proximity of the X(3872) to D(*0)D(0) threshold. We show that for total width 3 MeV and one unit of orbital angular momentum, a mass shift approximately 3 MeV/c(2) is obtained; experimental mass resolution should slightly increase this value. A consequence is that spin-parity 2(-) is favored for the X(3872).

5.
Gut ; 31(4): 401-5, 1990 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2338264

RESUMO

A validated postal questionnaire has been used to establish the prevalence of dyspeptic symptoms in five geographical locations from the south coast of England to the north of Scotland. The six month period prevalence of dyspepsia in the 7428 respondents to the questionnaire is 41% and equal between the sexes, with similar prevalence rates in the centres studied. There is considerable overlap between upper abdominal symptoms and symptoms of heartburn; 56% of patients with dyspepsia experience both groups of symptoms. Symptom frequency falls progressively with age in men and women, but the proportion of people seeking medical advice for dyspepsia rises with age. One quarter of the dyspeptic patients studied have consulted a general practitioner about their symptoms. This study suggests that the prevalence of dyspepsia in the community has changed little over the last 30 years, despite evidence that the frequency of peptic ulcer disease is falling. Symptom prevalence is unrelated to social class, but this factor is associated with consultation behaviour, the consultation rate rising from 17% in social class 1 to 29% in social class 4. The use of investigations--barium meal and endoscopy--is similarly related to social class; the lowest rate for ulcer diagnosis (4.7%) is found in social class 1 and the highest (17.1%) in social class 5.


Assuntos
Dispepsia/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Inglaterra/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Escócia/epidemiologia , Fatores Sexuais , Classe Social
6.
Phys Rev Lett ; 88(10): 101802, 2002 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-11909342

RESUMO

We report values of R = sigma(e(+)e(-)-->hadrons)/sigma(e(+)e(-)-->mu(+)mu(-)) for 85 center-of-mass energies between 2 and 5 GeV measured with the upgraded Beijing Spectrometer at the Beijing Electron-Positron Collider.

7.
Phys Rev Lett ; 91(2): 022001, 2003 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-12906471

RESUMO

We observe a narrow enhancement near 2m(p) in the invariant mass spectrum of pp pairs from radiative J/psi-->gammapp decays. No similar structure is seen in J/psi-->pi(0)pp decays. The results are based on an analysis of a 58 x 10(6) event sample of J/psi decays accumulated with the BESII detector at the Beijing electron-positron collider. The enhancement can be fit with either an S- or P-wave Breit-Wigner resonance function. In the case of the S-wave fit, the peak mass is below 2m(p) at M=1859(+3)(-10) (stat)+5-25(syst) MeV/c(2) and the total width is Gamma<30 MeV/c(2) at the 90% confidence level. These mass and width values are not consistent with the properties of any known particle.

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