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Author Albertus, C.; Hernandez, E.; Nieves, J.
Title Hyperfine mixing in electromagnetic decay of doubly heavy bc baryons Type Journal Article
Year 2010 Publication (down) Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 690 Issue 3 Pages 265-271
Keywords Hyperfine mixing; Double heavy bc baryons
Abstract We investigate the role of hyperfine mixing in the electromagnetic decay of ground state doubly heavy bc baryons. As in the case of a previous calculation on b -> c semileptonic decays of doubly heavy baryons, we find large corrections to the electromagnetic decay widths due to this mixing. Contrary to the weak case just mentioned, we find here that one cannot use electromagnetic width relations obtained in the infinite heavy quark mass limit to experimentally extract information on the admixtures in a model independent way.
Address [Albertus, C.; Hernandez, E.] Univ Salamanca, Dept Fis Fundamental, E-37008 Salamanca, Spain, Email: gajatee@usal.es
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0370-2693 ISBN Medium
Area Expedition Conference
Notes ISI:000279388800012 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ elepoucu @ Serial 416
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Author Albertus, C.; Hernandez, E.; Nieves, J.
Title Hyperfine mixing in b -> c semileptonic decay of doubly heavy baryons Type Journal Article
Year 2010 Publication (down) Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 683 Issue 1 Pages 21-25
Keywords
Abstract We qualitatively corroborate the results of [W. Roberts, M. Pervin, Int. J. Mod. Phys. A 24 (2009) 2401] according to which hyperfine mixing greatly affects the decay widths of b -> c semileptonic decays involving doubly heavy bc baryons. However, our predictions for the decay widths of the unmixed states differ from those reported in the work of Roberts and Pervin by a factor of 2, and this discrepancy translates to the mixed case. We further show that the predictions of heavy quark spin symmetry, might be used in the future to experimentally extract information on the admixtures in the actual physical bc baryons, in a model independent manner.
Address [Hernandez, E.] Univ Salamanca, Dept Fis Fundamental, E-37008 Salamanca, Spain, Email: gajatee@usal.es
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0370-2693 ISBN Medium
Area Expedition Conference
Notes ISI:000274129600005 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ elepoucu @ Serial 501
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Author Albertus, C.; Hernandez, E.; Nieves, J.
Title Exclusive c -> s, d semileptonic decays of ground-state spin-1/2 doubly charmed baryons Type Journal Article
Year 2011 Publication (down) Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 704 Issue 5 Pages 499-509
Keywords
Abstract We evaluate exclusive semileptonic decays of ground-state spin-1/2 doubly heavy charmed baryons driven by a c -> s, d transition at the quark level. Our results for the form factors are consistent with heavy quark spin symmetry constraints which are valid in the limit of an infinitely massive charm quark and near zero recoil. Only a few exclusive semileptonic decay channels have been theoretically analyzed before. For those cases we find that our results are in a reasonable agreement with previous calculations.
Address [Albertus, C.; Hernandez, E.] Univ Salamanca, Dept Fis Fundamental, E-37008 Salamanca, Spain, Email: gajatee@usal.es
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0370-2693 ISBN Medium
Area Expedition Conference
Notes WOS:000296549200017 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ elepoucu @ Serial 828
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Author Albertus, C.; Hernandez, E.; Hidalgo-Duque, C.; Nieves, J.
Title (B)over-bar(s) -> K semileptonic decay from an Omnes improved constituent quark model Type Journal Article
Year 2014 Publication (down) Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 738 Issue Pages 144-149
Keywords
Abstract We study the f(+) form factor for the semileptonic (B) over bar (s) -> K+ l(-) (V) over bar (l) decay in a constituent quark model. The valence quark estimate is supplemented with the contribution from the (B) over bar* pole that dominates the high q(2) region. We use a multiply-subtracted Omnes dispersion relation to extend the quark model predictions from its region of applicability near q(max)(2) = (M-Bs – M-K)(2) similar to 23.75 GeV2 to all q(2) values accessible in the physical decay. To better constrain the dependence of f(+) on q(2), we fit the subtraction constants to a combined input from previous light cone sum rule by Duplancic and Melic (2008) [11] and the present quark model results. From this analysis, we obtain Gamma ( (B) over bar (s) -> K+ l(-) (V) over bar (l)) = (5.47(-0.46)(+0.54)) vertical bar Vub vertical bar(2) x 10(-9) MeV, which is about 10% and 20% higher than the predictions based on Lattice QCD and QCD light cone sum rules respectively. The former predictions, for both the form factor f(+) (q(2)) and the differential decay width, lie within the 1 sigma band of our estimated uncertainties for all q(2) values accessible in the physical decay, except for a quite small region very close to q(max)(2). Differences with the light cone sum results for the form factor f(+) are larger than 20% in the region above q(2) = 15 GeV2.
Address [Albertus, C.] Univ Granada, Dept Fis Atom Nucl & Mol, E-18071 Granada, Spain
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0370-2693 ISBN Medium
Area Expedition Conference
Notes WOS:000344624900022 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 2020
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Author Hernandez, E.; Vijande, J.; Valcarce, A.; Richard, J.M.
Title Spectroscopy, lifetime and decay modes of the T-bb(-) tetraquark Type Journal Article
Year 2020 Publication (down) Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 800 Issue Pages 135073 - 9pp
Keywords
Abstract We present the first full-fledged study of the flavor-exotic isoscalar T-bb(-) equivalent to bb (u) over bar(d) over bar tetraquark with spin and parity J(P) = 1(+). We report accurate solutions of the four-body problem in a quark model, characterizing the structure of the state as a function of the ratio M-Q/m(q) of the heavy to light quark masses. For such a standard constituent model, T-bb(-) lies approximately 150 MeV below the strong decay threshold B- (B) over bar*(0) and 105 MeV below the electromagnetic decay threshold B- (B) over bar (0)gamma. We evaluate the lifetime of T-bb(-), identifying the promising decay modes where the tetraquark might be looked for in future experiments. Its total decay width is Gamma approximate to 87 x 10(-15) GeV and therefore its lifetime tau approximate to 7.6 ps. The promising final states are B*(-) D*(+) l (v) over bar (l) and (B) over bar*(0) l (v) over bar (l) among the semileptonic decays, and B*(-) D*(+) D-s*(-), (B) over bar*(0) D*(0) D-s*(-), and B*(-) D*(+) rho(-) among the nonleptonic ones. The semileptonic decay to the isoscalar J(P) = 0(+) tetraquark T-bc(0) is also relevant but it is not found to be dominant. There is a broad consensus about the existence of this tetraquark, and its detection will validate our understanding of the low-energy realizations of Quantum Chromodynamics (QCD) in the multiquark sector.
Address [Hernandez, E.; Valcarce, A.] Univ Salamanca, Dept Fis Fundamental, E-37008 Salamanca, Spain, Email: gajatee@usal.es;
Corporate Author Thesis
Publisher Elsevier Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0370-2693 ISBN Medium
Area Expedition Conference
Notes WOS:000503832500055 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4240
Permanent link to this record