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1.
Adv Struct Chem Imaging ; 3(1): 3, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28261541

RESUMEN

The data systems for X-ray free-electron laser (FEL) experiments at the Linac coherent light source (LCLS) are described. These systems are designed to acquire and to reliably transport shot-by-shot data at a peak throughput of 5 GB/s to the offline data storage where experimental data and the relevant metadata are archived and made available for user analysis. The analysis and monitoring implementation (AMI) and Photon Science ANAlysis (psana) software packages are described. Psana is open source and freely available.

2.
Klin Lab Diagn ; (1): 36-8, 2012 Jan.
Artículo en Ruso | MEDLINE | ID: mdl-22545474

RESUMEN

The article discusses the effectiveness of the technique of immune-enzyme detection of anti-botulin antibodies type A in human blood serum. The presence of antibodies is registered in blood serum after second and subsequent immunization with botulin trianatoxin (titer from 1:400 to 1:3200). The establishment of relationship between the registered titers of anti-botulin antibodies and the activity of serum during protection of white mice from toxin revealed the correlation coefficient between these values as 0.58.


Asunto(s)
Anticuerpos Antibacterianos/sangre , Toxinas Botulínicas , Inmunización , Toxoides/administración & dosificación , Animales , Anticuerpos Antibacterianos/inmunología , Botulismo/sangre , Botulismo/inmunología , Botulismo/prevención & control , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Masculino , Ratones , Toxoides/inmunología
4.
Phys Rev Lett ; 101(19): 192001, 2008 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-19113261

RESUMEN

We report the first observation of Upsilon(2S)-->etaUpsilon(1S), with a branching fraction B=(2.1(-0.6)+0.7(stat)+/-0.3(syst)) x 10(-4) and a statistical significance 5.3sigma. Data were acquired with the CLEO III detector at the CESR e+e(-) symmetric collider. This is the first process observed involving a b-quark spin flip. For related transitions, 90% confidence limits in units of 10(-4) are B(Upsilon(2S)-->pi0Upsilon(1S)) < 1.8, B(Upsilon(3S)-->etaUpsilon(1S)) < 1.8, B(Upsilon(3S)-->pi0Upsilon(1S)) < 0.7, and B(Upsilon(3S)-->pi0Upsilon(2S)) < 5.1.

5.
Phys Rev Lett ; 101(20): 201601, 2008 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-19113327

RESUMEN

In this Letter, we describe a search for lepton flavor violation (LFV) in the bottomonium system. We search for leptonic decays Upsilon(nS)-->mutau (n=1, 2, and 3) using the data collected with the CLEO III detector. We identify the tau lepton using its leptonic decay nu_{tau}nu[over ]_{e}e and utilize multidimensional likelihood fitting with probability density function shapes measured from independent data samples. We report our estimates of 95% C.L. upper limits on LFV branching fractions of Upsilon mesons. We interpret our results in terms of the exclusion plot for the energy scale of a hypothetical new interaction versus its effective LFV coupling in the framework of effective field theory.

6.
Phys Rev Lett ; 101(15): 151802, 2008 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-18999589

RESUMEN

We search for a non-SM-like CP-odd Higgs boson (a(1)(0)) decaying to tau(+)tau(-) or mu(+)mu(-) in radiative decays of the Upsilon(1S). No significant signal is found, and upper limits on the product branching ratios are set. Our tau(+)tau(-) results are almost 2 orders of magnitude more stringent than previous upper limits. Our data provide no evidence for a Higgs state with a mass of 214 MeV decaying to mu(+)mu(-), previously proposed as an explanation for 3 Sigma(+)-->pmu(+)mu(-) events observed by the HyperCP experiment. Our results constrain NMSSM models.

7.
Phys Rev Lett ; 101(18): 182002, 2008 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-18999819

RESUMEN

We measure the mass of the eta;{'} meson using psi(2S)-->pi;{+}pi;{-}J/psi, J/psi-->gammaeta;{'} events acquired with the CLEO-c detector operating at the CESR e;{+}e;{-} collider. Using three decay modes, eta;{'}-->rho;{0}gamma, eta;{'}-->pi;{+}pi;{-}eta with eta-->gammagamma, and eta;{'}-->pi;{+}pi;{-}eta with eta-->pi;{+}pi;{-}pi;{0}, we find M_{eta;{'}}=957.793+/-0.054+/-0.036 MeV, in which the uncertainties are statistical and systematic, respectively. This result is consistent with but substantially more precise than the current world average.

8.
Phys Rev Lett ; 101(18): 182003, 2008 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-18999820

RESUMEN

A precision measurement of the mass of the h_{c}(1P1) state of charmonium has been made using a sample of 24.5x10;{6} psi(2S) events produced in e;{+}e;{-} annihilation at the Cornell Electron Storage Ring (CESR). The reaction used was psi(2S)-->pi;{0}h_{c}, pi;{0}-->gammagamma, h_{c}-->gammaeta_{c}, and the reaction products were detected in the CLEO-c detector. Data have been analyzed both for the inclusive reaction and for the exclusive reactions in which eta_{c} decays are reconstructed in 15 hadronic decay channels. Consistent results are obtained in the two analyses. The averaged results of the present measurements are M(h_{c})=3525.28+/-0.19(stat.)+/-0.12(syst.) MeV, and B(psi(2S)-->pi;{0}h_{c})xB(h_{c}-->gammaeta_{c})=(4.19+/-0.32+/-0.45)x10;{-4}. Using the ;{3}P_{J} centroid mass, DeltaM_{hf}(1P) identical withM(chi_{cJ})-M(h_{c})=+0.02+/-0.19+/-0.13 MeV.

9.
Phys Rev Lett ; 101(10): 101801, 2008 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-18851203

RESUMEN

We report the first observation of the decay J/psi-->3gamma. The signal has a statistical significance of 6sigma and corresponds to a branching fraction of B(J/psi-->3gamma)=(1.2+/-0.3+/-0.2)x10;{-5}, in which the errors are statistical and systematic, respectively. The measurement uses psi(2S)-->pi;{+}pi;{-}J/psi events acquired with the CLEO-c detector operating at the CESR e;{+}e;{-} collider.

10.
Phys Rev Lett ; 100(16): 161801, 2008 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-18518183

RESUMEN

Using a sample of tagged D(s)(+) decays collected near the D(s)(*+/-)D(s)(-/+) peak production energy in e(+)e(-) collisions with the CLEO-c detector, we study the leptonic decay D(s)(+)-->tau(+)nu(tau) via the decay channel tau(+)-->e(+)nu(e)nu(tau). We measure B(D(s)(+)-->tau(+)nu(tau))=(6.17+/-0.71+/-0.34)%, where the first error is statistical and the second systematic. Combining this result with our measurements of D(s)(+)-->mu(+)nu(mu) and D(s)(+)-->tau(+)nu(tau) (via tau(+)-->pi(+)nu(tau)), we determine f(D(s))=(274+/-10+/-5) MeV.

11.
Phys Rev Lett ; 100(9): 091801, 2008 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-18352696

RESUMEN

We present measurements of D--> KS0 pi and D--> KL0 pi branching fractions using 281 pb(-1) of psi(3770) data at the CLEO-c experiment. We find that B(D0--> KS0 pi 0) is larger than B(D0--> KL0 pi 0), with an asymmetry of R(D0)=0.108+/-0.025+/-0.024. For B(D+--> KS0 pi+) and B(D+--> KL0 pi+), we observe no measurable difference; the asymmetry is R(D+)=0.022+/-0.016+/-0.018. The D0 asymmetry is consistent with the value based on the U-spin prediction A(D0--> K0 pi 0)/A(D0--> K0 pi 0)=-tan2 theta C, where theta C is the Cabibbo angle.

12.
Phys Rev Lett ; 99(12): 122001, 2007 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-17930497

RESUMEN

The decay psi(2S) --> etaJ/psi is used to measure, for the first time, all prominent eta-meson branching fractions with the same experiment in the same dataset, thereby providing a consistent treatment of systematics across branching fractions. We present results for eta decays to gamma gamma, pi(+)pi(-)pi(0), 3pi(0), pi(+)pi(-)gamma and e(+)e(-)gamma, accounting for 99.9% of all eta decays. The precision of several of the branching fractions and their ratios is improved. Two channels, pi(+)pi(-)gamma and e(+)e(-)gamma, show results that differ at the level of three standard deviations from those previously determined.

13.
Phys Rev Lett ; 99(12): 122002, 2007 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-17930498

RESUMEN

We measure the mass of the eta meson using psi(2S) --> etaJ/psi events acquired with the CLEO-c detector operating at the CESR e(+)e(-) collider. Using the four decay modes eta --> gamma gamma, 3pi(0), pi(+)pi(-)pi(0), and pi(+)pi(-)gamma, we find M(eta) = 547.785 +/- 0.017 +/- 0.057 MeV, in which the first uncertainty is statistical and the second systematic. This result has an uncertainty comparable to the two most precise previous measurements and is consistent with that of NA48, but is inconsistent at the level of 6.5 sigma with the much smaller mass obtained by GEM.

14.
Phys Rev Lett ; 99(7): 071802, 2007 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-17930886

RESUMEN

We measure the decay constant f(Ds+) using the D(s+)-->l+ nu channel, where the l+ designates either a mu+ or a tau+, when the tau+ -->pi+ nu. Using both measurements we find f(Ds+)=274+/-13+/-7 MeV. Combining with our previous determination of f(D+), we compute the ratio f(Ds+)/f(D+)=1.23+/-0.11+/-0.04. We compare with theoretical estimates.

16.
Phys Rev Lett ; 99(19): 191801, 2007 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-18233062

RESUMEN

Using a 281 pb{-1} data sample collected at the psi(3770) with the CLEO-c detector, we present the first absolute branching fraction measurement of the decay D0-->K(-)pi(+)pi(-)e(+)nu(e) at a statistical significance of about 4.0 standard deviations. We find 10 candidates consistent with the decay D0-->K(-)pi(+)pi(-)e(+)nu(e). The probability that a background fluctuation accounts for this signal is less than 4.1 x 10{-5}. We find B(D0-->K(-)pi(+)pi(-)e(+)nu(e)) = [2.8{-1.1}{+1.4}(stat)+/-0.3(syst)]x10{-4}. By restricting the invariant mass of the hadronic system to be consistent with K1(1270), we obtain the product of branching fractions B(D{0}-->K{1}{-}(1270)e{+}nu{e})xB(K1-(1270)-->K{-}pi{+}pi{-})=[2.5{-1.0}{+1.3}(stat)+/-0.2(syst)]x10{-4}. Using B(K1-(1270)-->K{-}pi{+}pi{-})=(33+/-3)%, we obtain B(D{0}-->K{1}{-}(1270)e{+}nu{e})=[7.6{-3.0}{+4.1}(stat)+/-0.6(syst)+/-0.7]x10{-4}. The last error accounts for the uncertainties in the measured K1-(1270)-->K{-}pi{+}pi{-} branching fractions.

17.
Phys Rev Lett ; 99(19): 191805, 2007 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-18233066

RESUMEN

Using data collected near the D{s}{*+}D{s}{-} peak production energy E_{cm}=4170 MeV by the CLEO-c detector, we study the decays of D{s}{+} mesons to two pseudoscalar mesons. We report on searches for the singly Cabibbo-suppressed D{s}{+} decay modes K{+}eta, K{+}eta', pi{+}K{S}{0}, K{+}pi{0}, and the isospin-forbidden decay mode D{s}{+}-->pi{+}pi{0}. We normalize with respect to the Cabibbo-favored D{s}{+} modes pi{+}eta, pi{+}eta', and K{+}K{S}{0}, and obtain ratios of branching fractions: B(D{s}{+}-->K{+}eta)/B(D{s}{+}-->pi{+}eta)=(8.9+/-1.5+/-0.4)%, B(D{s}{+}-->K{+}eta')/B(D{s}{+}-->pi{+}eta')=(4.2+/-1.3+/-0.3)%, B(D{s}{+}-->pi{+}K{S}{0})/B(D{s}{+}-->K{+}K{S}{0})=(8.2+/-0.9+/-0.2)%, B(D{s}{+}-->K{+}pi{0})/B(D{s}{+}-->K{+}K{S}{0})=(5.5+/-1.3+/-0.7)%, and B(D{s}{+}-->pi{+}pi{0})/B(D{s}{+}-->K{+}K{S}{0})<4.1% at 90% C.L., where the uncertainties are statistical and systematic, respectively.

18.
Phys Rev Lett ; 96(15): 152001, 2006 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-16712149

RESUMEN

Using 420 pb(-1) of data collected on the upsilon(5S) resonance with the CLEO III detector, we reconstruct B mesons in 25 exclusive decay channels to measure or set upper limits on the decay rate of upsilon(5S) into B meson final states. We measure the inclusive B cross section to be sigma(upsilon(5S) --> BB(X)) = (0.177 +/- 0.030 +/- 0.016) nb and make the first measurements of the production rates of sigma(upsilon(5S) --> B*B*) = (0.131 +/- 0.025 +/- 0.014) nb and sigma(upsilon(5S) --> BB*) = (0.043 +/- 0.016 +/- 0.006) nb, respectively. We set 90% confidence level limits of sigma(upsilon(5S) -->BB) < 0.038 nb, sigma(upsilon(5S) --> B(*)B(*)pi) < 0.055 nb and sigma(upsilon(5S) --> BBpipi) < 0.024 nb. We also extract the most precise value of the B(s)* mass to date, M(B(s)*) = (5411.7 +/- 1.6 +/- 0.6) MeV/c2.

19.
Phys Rev Lett ; 96(16): 162003, 2006 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-16712216

RESUMEN

Using data collected with the CLEO detector operating at the CESR e+e- collider at sqrt[s]=3.97-4.26 GeV, we investigate 15 charmonium decay modes of the psi(4040), psi(4160), and Y(4260) resonances. We confirm, at 11 sigma significance, the BABAR Y(4260)-->pi+pi- J/psi discovery, make the first observation of Y(4260)--> pi(0)pi(0) J/psi (5.1 sigma), and find the first evidence for Y(4260)-->K+K- J/psi(3.7 sigma). We measure e+e- cross sections at sqrt[s]=4.26 GeV as sigma(pi+pi- J/psi)=58(+12)(-10)+/-4 pb, sigma(pi(0)pi(0) J/psi)=23(+12)(-8)+/-1 pb, and sigma(K+K- J/psi)=9(+9)(-5)+/-1 pb, in which the uncertainties are statistical and systematic, respectively. Upper limits are placed on other decay rates from all three resonances.

20.
Phys Rev Lett ; 96(18): 182002, 2006 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-16712360

RESUMEN

From e(+)e(-) collision data acquired with the CLEO detector at the Cornell Electron Storage Ring, we observe the non-DD(_) decay Psi(3770))-->gammachi(c1) with a statistical significance of 6.6 standard deviations, using the two-photon cascades to J/Psi and J/Psi-->l(+)l(-). We determine sigma(e(=)e(-)-->Psi(3770))xBeta(Psi(3770)-->gammachi(c1))=(18.0 +/- 3.3 +/- 2.5) pb and branching fraction Beta(Psi(3770)-->gammachi(c1)=(2.8 +/- 0.5+/-0.4) x 10(-3). We set 90% C.L. upper limits for the transition to chi(c2) (chi(c0)): sigma x Beta<5.7 pb (<282 pb) and Beta<0.9 x 10(-3) (<44 x 10(-3)). We also determine Gamma(Psi(3770)gammachi(c1))/Gamma(Psi(3770)-->pi(+)pi(-)J/Psi)=1.5 +/- 0.3 +/- 0.3 (>1.0 at 90% C.L.), which bears upon the interpretation of X(3872).

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