toggle visibility Search & Display Options

Select All    Deselect All
 |   | 
Details
   print
  Records Links
Author (up) Bayar, M.; Pavao, R.; Sakai, S.; Oset, E. url  doi
openurl 
  Title Role of the triangle singularity in Lambda(1405) production in the pi(-) p -> K-0 pi Sigma and pp -> pK(+) pi Sigma processes Type Journal Article
  Year 2018 Publication Physical Review C Abbreviated Journal Phys. Rev. C  
  Volume 97 Issue 3 Pages 035203 - 12pp  
  Keywords  
  Abstract We have investigated the cross section for the pi(-) p -> K-0 pi Sigma and pp -> pK(+) pi Sigma reactions, paying attention to a mechanism that develops a triangle singularity. The triangle diagram is realized by the decay of a N* to K* Sigma and the K* decay into pi K, and the pi Sigma finally merges into Lambda (1405). The mechanism is expected to produce a peak around 2140 MeV in the K Lambda (1405) invariant mass. We found that a clear peak appears around 2100 MeV in the K Lambda (1405) invariant mass, which is about 40 MeV lower than the expectation, and that is due to the resonance peak of a N* resonance which plays a crucial role in the K* Sigma production. The mechanism studied produces the peak of the Lambda (1405) around or below 1400 MeV, as is seen in the pp -> pK(+) pi Sigma HADES experiment.  
  Address [Bayar, M.] Kocaeli Univ, Dept Phys, TR-41380 Izmit, Turkey, Email: melahat.bayar@kocaeli.edu.tr  
  Corporate Author Thesis  
  Publisher Amer Physical Soc Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2469-9985 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000426780000004 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 3510  
Permanent link to this record
 

 
Author (up) Dai, L.R.; Pavao, R.; Sakai, S.; Oset, E. url  doi
openurl 
  Title tau(-) -> nu tau M1 M2, with M1, M2 pseudoscalar or vector mesons Type Journal Article
  Year 2019 Publication European Physical Journal A Abbreviated Journal Eur. Phys. J. A  
  Volume 55 Issue 2 Pages 20 - 22pp  
  Keywords  
  Abstract .We perform a calculation of the -M1M2, with M1,M2 either pseudoscalar or vector mesons using the basic weak interaction and angular momentum algebra to relate the different processes. The formalism also leads to a different interpretation of the role played by G-parity in these decays. We also observe that, while PPp-wave production is compatible with chiral perturbation theory and experiment, VP and VVp-wave production is clearly incompatible with experiment and we develop the formalism also in this case, producing the VP or VV pairs in s-wave. We compare our results with experiment and other theoretical approaches for rates and invariant mass distributions and make predictions for unmeasured decays. We show the value of these reactions, particularly if the M1M2 mass distribution is measured, as a tool to learn about the meson-meson interaction and the nature of some resonances, coupling to two mesons, which are produced in such decays.  
  Address [Dai, L. R.] Liaoning Normal Univ, Dept Phys, Dalian 116029, Peoples R China, Email: dailr@lnnu.edu.cn;  
  Corporate Author Thesis  
  Publisher Springer Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1434-6001 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000458818600001 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 3910  
Permanent link to this record
 

 
Author (up) Dai, L.R.; Pavao, R.; Sakai, S.; Oset, E. url  doi
openurl 
  Title Anomalous enhancement of the isospin-violating Lambda(1405) production by a triangle singularity in Lambda(c) ->pi(+)pi(0)pi(0)Sigma(0) Type Journal Article
  Year 2018 Publication Physical Review D Abbreviated Journal Phys. Rev. D  
  Volume 97 Issue 11 Pages 116004 - 10pp  
  Keywords  
  Abstract The decay of Lambda(+)(c) into pi(+)pi(0) Lambda(1405) with the Lambda(1405) decay into pi(0)Sigma(0) through a triangle diagram is studied. This process is initiated by Lambda(+)(c) -> pi(+) (K) over bar N-*, and then the (K) over bar (*) decays into (K) over bar (pi) and (K) over bar N produce the Lambda(1405) through a triangle loop containing (K) over bar N-* (K) over bar which develops a singularity around 1890 MeV. This process is prohibited by the isospin symmetry, but the decay into this channel is enhanced by the contribution of the triangle diagram, which is sensitive to the mass of the internal particles. We find a narrow peak in the pi(0)Sigma(0) invariant mass distribution, which originates from the (K) over bar amplitude, but is tied to the mass differences between the charged and neutral (K) over bar or N states. The observation of the unavoidable peak of the triangle singularity in the isospin- violating Lambda(1405) production would provide further support for the hadronic molecular picture of the Lambda(1405) and further information on the (K) over bar N interaction.  
  Address [Dai, L. R.] Liaoning Normal Univ, Dept Phys, Dalian 116029, Peoples R China, Email: dailr@lnnu.edu.cn;  
  Corporate Author Thesis  
  Publisher Amer Physical Soc Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2470-0010 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000434211200013 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 3602  
Permanent link to this record
 

 
Author (up) Faleiro, R.; Pavao, R.; Costa, H.A.S.; Hiller, B.; Blin, A.H.; Sampaio, M. url  doi
openurl 
  Title Perturbative approach to entanglement generation in QFT using the S matrix Type Journal Article
  Year 2020 Publication Journal of Physics A Abbreviated Journal J. Phys. A  
  Volume 53 Issue 36 Pages 365301 - 19pp  
  Keywords S-matrix; entanglement; QFT; cross-section  
  Abstract We compute the variation of the von Neumann (VN) entropy Delta Sbetween the asymptoticinandoutmomenta modes of a real scalar field A, when elastically scattered against the modes of another scalar field B. This is done to see how the entanglement between the two fields' momenta changes under the scattering procedure. The calculation is separated into two case studies, one where the fields' asymptoticinstates are separable, and another where they are arbitrarily entangled. We perform a perturbative calculation to one loop order in the separable case, and verify that Delta Schanges in a non-trivial way when we vary the momentum of the incoming field modes and/or the coupling of the theory. Finally, also in the separable case, we show an explicit dependence between Delta Sand the cross-section of the collision, consistent with perturbation theory.  
  Address [Faleiro, Ricardo; Hiller, Brigitte] Univ Lisbon, Dept Math, Ave Rovisco Pais, P-1049001 Lisbon, Portugal, Email: ricardofaleiro@tecnico.ulisboa.pt  
  Corporate Author Thesis  
  Publisher Iop Publishing Ltd Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1751-8113 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000563486000001 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 4511  
Permanent link to this record
 

 
Author (up) Nieves, J.; Pavao, R. url  doi
openurl 
  Title Nature of the lowest-lying odd parity charmed baryon Lambda(c)(2595) and Lambda(c)(2625) resonances Type Journal Article
  Year 2020 Publication Physical Review D Abbreviated Journal Phys. Rev. D  
  Volume 101 Issue 1 Pages 014018 - 17pp  
  Keywords  
  Abstract We study the structure of the Lambda(c) (2595) and Lambda(c) (2625) resonances in the framework of an effective field theory consistent with heavy quark spin and chiral symmetries, which incorporates the interplay between Sigma(()(c)*() )pi – ND(*()) baryon-meson degrees of freedom (d.o.f.) and bare P-wave c (u) over bard quark-model states. We show that these two resonances are not heavy quark spin symmetry partners. The J(P) = 3/2(-) Lambda(c) (2625) should be viewed mostly as a dressed three-quark state, whose origin is determined by a bare state, predicted to lie very close to the mass of the resonance. The J(P) = 1/2(-) Lambda(c) (2595) seems to have, however, a predominant molecular structure. This is because it is either the result of the chiral Sigma(c)pi interaction, whose threshold is located much closer than the mass of the bare three-quark state, or because the light d.o.f. in its inner structure are coupled to the unnatural 0(-) quantum numbers. We show that both situations can occur depending on the renormalization procedure used. We find some additional states, but the classification of the spectrum in terms of heavy quark spin symmetry is difficult, despite having used interactions that respect this symmetry. This is because the bare quark-model state and the Sigma(c)pi threshold are located extraordinarily close to the Lambda(c) (2625) and Lambda(c) (2595), respectively, and hence they play totally different roles in each sector.  
  Address [Nieves, J.; Pavao, R.] Ctr Mixto CSIC UV, Inst Invest Paterna, Inst Fis Corpuscular, Apartado 22085, Valencia 46071, Spain  
  Corporate Author Thesis  
  Publisher Amer Physical Soc Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2470-0010 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000509494900007 Approved no  
  Is ISI yes International Collaboration no  
  Call Number IFIC @ pastor @ Serial 4272  
Permanent link to this record
Select All    Deselect All
 |   | 
Details
   print

Save Citations:
Export Records:
ific federMinisterio de Ciencia e InnovaciĆ³nAgencia Estatal de Investigaciongva