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61.
Abazov VM Abbott B Abolins M Acharya BS Adams M Adams T Aguilo E Ahn SH Ahsan M Alexeev GD Alkhazov G Alton A Alverson G Alves GA Anastasoaie M Ancu LS Andeen T Anderson S Andrieu B Anzelc MS Arnoud Y Arov M Arthaud M Askew A Asman B Assis Jesus AC Atramentov O Autermann C Avila C Ay C Badaud F Baden A Bagby L Baldin B Bandurin DV Banerjee S Banerjee P Barberis E Barfuss AF Bargassa P Baringer P Barreto J Bartlett JF Bassler U Bauer D Beale S Bean A Begalli M Begel M Belanger-Champagne C 《Physical review letters》2007,99(18):182001
We report a measurement of the Lambda(b)(0) lifetime using a sample corresponding to 1.3 fb(-1) of data collected by the D0 experiment in 2002-2006 during run II of the Fermilab Tevatron collider. The Lambda(b)(0) baryon is reconstructed via the decay Lambda(b)(0)-->micronuLambda(c)(+)X. Using 4437+/-329 signal candidates, we measure the Lambda(b)(0) lifetime to be tau(Lambda(b)(0))=1.290(-0.110)(+0.119)(stat)(-0.091)(+0.087)(syst) ps, which is among the most precise measurements in semileptonic Lambda(b)(0) decays. This result is in good agreement with the world average value. 相似文献
62.
Abazov VM Abbott B Abolins M Acharya BS Adams M Adams T Aguilo E Ahn SH Ahsan M Alexeev GD Alkhazov G Alton A Alverson G Alves GA Anastasoaie M Ancu LS Andeen T Anderson S Andrieu B Anzelc MS Arnoud Y Arov M Arthaud M Askew A Asman B Assis Jesus AC Atramentov O Autermann C Avila C Ay C Badaud F Baden A Bagby L Baldin B Bandurin DV Banerjee S Banerjee P Barberis E Barfuss AF Bargassa P Baringer P Barreto J Bartlett JF Bassler U Bauer D Beale S Bean A Begalli M Begel M Belanger-Champagne C 《Physical review letters》2007,99(17):172001
This Letter presents the first strong evidence for the resolution of the excited B mesons B(1) and B(2)* as two separate states in fully reconstructed decays to B(+)(*)pi(-). The mass of B(1) is measured to be 5720.6+/-2.4+/-1.4 MeV/c(2) and the mass difference DeltaM between B(2)* and B(1) is 26.2+/-3.1+/-0.9 MeV/c;{2}, giving the mass of the B(2)* as 5746.8+/-2.4+/-1.7 MeV/c(2). The production rate for B(1) and B(2)* mesons is determined to be a fraction (13.9+/-1.9+/-3.2)% of the production rate of the B+ meson. 相似文献
63.
64.
T. A. W. Beale G. Beutier S. R. Bland A. Bombardi L. Bouchenoire O. Bun?u S. Di Matteo J. Fernández-Rodríguez J. E. Hamann-Borrero J. Herrero-Martín V. L. R. Jacques R. D. Johnson A. Juhin T. Matsumura C. Mazzoli A. M. Mulders H. Nakao J. Okamoto S. Partzsch A. J. Princep V. Scagnoli J. Strempfer C. Vecchini Y. Wakabayashi H. C. Walker D. Wermeille Y. Yamasaki 《The European physical journal. Special topics》2012,208(1):89-98
Resonant Elastic X-Ray Scattering (REXS) has played a fundamental role in understanding electronic properties and in revealing hidden order, local symmetries and exotic states realized in correlated solids. This article reports on some of the relevant scientific contributions and technical advances over the last 20 years, by providing a list of related publications produced by various groups all around the world. The given perspective is that of a group of young scientists involved at various times in the investigation of the beauty of electronic ordering by the REXS technique. 相似文献
65.
J. Thomas Beale 《Journal of computational physics》2012,231(18):6159-6172
We develop a numerical method for the coupled motion of Navier–Stokes flow with an elastic interface of zero thickness which exerts tension and bending forces on the fluid. The interface motion is made partially implicit by approximating a backward Euler step in the high wavenumbers as in the small scale decomposition method of Hou, Lowengrub and Shelley. This modified step is combined with the method of Beale and Layton [J.T. Beale, A.T. Layton, A velocity decomposition approach for moving interfaces in viscous fluids, J. Comput. Phys. 228 (2009) 3358–67]; the fluid velocity is found by computing the Stokes velocity and a more regular remainder. The resulting scheme is second order in space and first order in time; it can be made second order in time by extrapolation. The discontinuities in the pressure and velocity gradient are preserved. The partially implicit method allows much larger time steps than an explicit method with negligible added effort. The formulas in the Fourier transform for the implicit approximation in high wavenumbers are similar to those derived in Hou and Shi [T.Y. Hou, Z. Shi, An efficient semi-implicit immersed boundary method for the Navier–Stokes equations, J. Comput. Phys. 227 (2008) 9138–69] in a different context. 相似文献
66.
Abazov VM Abbott B Abolins M Acharya BS Adams M Adams T Aguilo E Ahn SH Ahsan M Alexeev GD Alkhazov G Alton A Alverson G Alves GA Anastasoaie M Ancu LS Andeen T Anderson S Andrieu B Anzelc MS Aoki M Arnoud Y Arov M Arthaud M Askew A Asman B Assis Jesus AC Atramentov O Avila C Ay C Badaud F Baden A Bagby L Baldin B Bandurin DV Banerjee P Banerjee S Barberis E Barfuss AF Bargassa P Baringer P Barreto J Bartlett JF Bassler U Bauer D Beale S Bean A Begalli M Begel M Belanger-Champagne C 《Physical review letters》2008,100(24):241805
We present results from a study of pp-->Wgamma+X events utilizing data corresponding to 0.7 fb{-1} of integrated luminosity at sqrt[s]=1.96 TeV collected by the D0 detector at the Fermilab Tevatron Collider. We set limits on anomalous WWgamma couplings at the 95% C.L. The one-dimensional 95% C.L. limits are 0.49相似文献
67.
Abazov VM Abbott B Abolins M Acharya BS Adams M Adams T Aguilo E Ahsan M Alexeev GD Alkhazov G Alton A Alverson G Alves GA Anastasoaie M Ancu LS Andeen T Andrieu B Anzelc MS Aoki M Arnoud Y Arov M Arthaud M Askew A Asman B Jesus AC Atramentov O Avila C Badaud F Bagby L Baldin B Bandurin DV Banerjee P Banerjee S Barberis E Barfuss AF Bargassa P Baringer P Barreto J Bartlett JF Bassler U Bauer D Beale S Bean A Begalli M Begel M Belanger-Champagne C Bellantoni L Bellavance A Benitez JA Beri SB 《Physical review letters》2008,101(18):182001
We measure the mass of the top quark using top-quark pair candidate events in the lepton+jets channel from data corresponding to 1 fb;{-1} of integrated luminosity collected by the D0 experiment at the Fermilab Tevatron collider. We use a likelihood technique that reduces the jet energy scale uncertainty by combining an in situ jet energy calibration with the independent constraint on the jet energy scale (JES) from the calibration derived using photon+jets and dijet samples. We find the mass of the top quark to be 171.5+/-1.8(stat.+JES)+/-1.1(syst.) GeV. 相似文献
68.
Abazov VM Abbott B Abolins M Acharya BS Adams M Adams T Aguilo E Ahn SH Ahsan M Alexeev GD Alkhazov G Alton A Alverson G Alves GA Anastasoaie M Ancu LS Andeen T Anderson S Andrieu B Anzelc MS Aoki M Arnoud Y Arov M Arthaud M Askew A Asman B Assis Jesus AC Atramentov O Avila C Ay C Badaud F Baden A Bagby L Baldin B Bandurin DV Banerjee P Banerjee S Barberis E Barfuss AF Bargassa P Baringer P Barreto J Bartlett JF Bassler U Bauer D Beale S Bean A Begalli M Begel M Belanger-Champagne C 《Physical review letters》2008,100(19):192004
We measure the tt[over] production cross section in pp[over] collisions at sqrt(s)=1.96 TeV in the lepton + jets channel. Two complementary methods discriminate between signal and background: b tagging and a kinematic likelihood discriminant. Based on 0.9 fb(-1) of data collected by the D0 detector at the Fermilab Tevatron Collider, we measure sigma(tt[over])=7.62+/-0.85 pb, assuming the current world average m(t)=172.6 GeV. We compare our cross section measurement with theory predictions to determine a value for the top-quark mass of 170+/-7 GeV. 相似文献
69.
Vladimir Martis Andrew M. Beale Dirk Detollenaere Dipanjan Banerjee Martine Moroni Fabrice Gosselin Wim Bras 《Journal of synchrotron radiation》2014,21(2):462-463
A high‐pressure gas rig for in situ catalytic reactions at X‐ray absorption spectroscopy beamline (BM26A) has been developed. The rig enables catalysts to be studied in a variety of cells under well controlled and industrially relevant operation conditions. A large variety of gas mixtures can be generated and pressures of up to 50 bar with dry gas and 20 bar with wet gas (steam) can be obtained. Analyses of reaction products can be performed using an on‐line mass spectrometer. 相似文献
70.
Chengwu Qiu Yaroslav Odarchenko Qingwei Meng Peixi Cong Martin A. W. Schoen Armin Kleibert Thomas Forrest Andrew M. Beale 《Chemical science》2020,11(48):13060
Understanding the metal–support interaction (MSI) is crucial to comprehend how the catalyst support affects performance and whether this interaction can be exploited in order to design new catalysts with enhanced properties. Spatially resolved soft X-ray absorption spectroscopy (XAS) in combination with Atomic Force Microscopy (AFM) and Scanning Helium Ion-Milling Microscopy (SHIM) has been applied to visualise and characterise the behaviour of individual cobalt nanoparticles (CoNPs) supported on two-dimensional substrates (SiOxSi(100) (x < 2) and rutile TiO2(110)) after undergoing reduction–oxidation–reduction (ROR). The behaviour of the Co species is observed to be strongly dependent on the type of support. For SiOxSi a weaker MSI between Co and the support allows a complete reduction of CoNPs although they migrate and agglomerate. In contrast, a stronger MSI of CoNPs on TiO2 leads to only a partial reduction under H2 at 773 K (as observed from Co L3-edge XAS data) due to enhanced TiO2 binding of surface-exposed cobalt. SHIM data revealed that the interaction of the CoNPs is so strong on TiO2, that they are seen to spread at and below the surface and even to migrate up to ∼40 nm away. These results allow us to better understand deactivation phenomena and additionally demonstrate a new understanding concerning the nature of the MSI for Co/TiO2 and suggest that there is scope for careful control of the post-synthetic thermal treatment for the tuning of this interaction and ultimately the catalytic performance.Understanding the metal–support interaction (MSI) is crucial to comprehend how the catalyst support affects performance and whether this interaction can be exploited in order to design new catalysts with enhanced properties. 相似文献