The internal structure of the charm-strange mesons D_(s0)^(*)(2317)and D_(s1)(2460)are the subject of intensive studies.Their widths are small because they decay dominantly through isospinbreaking hadronic channels D_...The internal structure of the charm-strange mesons D_(s0)^(*)(2317)and D_(s1)(2460)are the subject of intensive studies.Their widths are small because they decay dominantly through isospinbreaking hadronic channels D_(s0)^(*)(2317)^(+)→D_(s)^(+)π^(0) and D _(s1)(2460)^(+)→D_(s)^(*+)π^(0).The D_(s1)(2460)can also decay into the hadronic final states D_(s)^(+)ππ,conserving isospin.In that case there is,however,a strong suppression from phase space.We study the transition D_(s1)(2460)^(+)→D_(s)^(+)π^(+)π^(-)in the scenario that the D_(s1)(2460)is a D^(*)K hadronic molecule.The ππ final state interaction is taken into account through dispersion relations.We find that the ratio of the partial widths of the Γ(D_(s1)(2460)^(+)→D_(s)^(+)π^(+)π^(-)) / Γ(D_(s1)(2460)^(+)→D_(s)^(*+)π^(0))obtained in the molecular picture is consistent with the existing experimental measurement.More interestingly,we demonstrate that theπ+π−invariant mass distribution shows a double bump structure,which can be used to disentangle the hadronic molecular picture from the compact state picture for the D_(s1)(2460)^(+).Predictions on the B_(s1)^(0)→B_(s)^(0)π^(+)π^(-)are also made.展开更多
We are exploring a generic strongly-interacting Electroweak Symmetry Breaking Sector(EWSBS) with the low-energy effective field theory for the four experimentally known particles(W_L~±,Z_l,h) and its dispersion-r...We are exploring a generic strongly-interacting Electroweak Symmetry Breaking Sector(EWSBS) with the low-energy effective field theory for the four experimentally known particles(W_L~±,Z_l,h) and its dispersion-relation based unitary extension.In this contribution we provide simple estimates for the production cross-section of pairs of the EWSBS bosons and their resonances at proton-proton colliders as well as in a future e^-e^+(or potentially aμ^-μ^+) collider with a typical few-TeV energy.We examine the simplest production mechanisms,tree-level production through a W(dominant when quantum numbers allow) and the simple effective boson approximation(in which the electroweak bosons are considered as collinear partons of the colliding fermions).We exemplify with custodial isovector and isotensor resonances at 2 TeV,the energy currently being discussed because of a slight excess in the ATLAS 2-jet data.We find it hard,though not unthinkable,to ascribe this excess to one of these W_lW_l rescattering resonances.An isovector resonance could be produced at a rate smaller than,but close to earlier CMS exclusion bounds,depending on the parameters of the effective theory.The ZZ excess is then problematic and requires additional physics(such as an additional scalar resonance).The isotensor one(that would describe all charge combinations) has smaller cross-section.展开更多
Neutron-antineutron(n−n)oscillations in the deuteron are considered.Specifically,the deuteron lifetime is calculated in terms of the free-space n−n oscillation time τn−n based on NN and NN interactions derived within...Neutron-antineutron(n−n)oscillations in the deuteron are considered.Specifically,the deuteron lifetime is calculated in terms of the free-space n−n oscillation time τn−n based on NN and NN interactions derived within chiral effective field theory(EFT).This results in(2.6±0.1)×10^22τ2^n−n s,which is close to the value obtained by Dover and collaborators more than three decades ago,but disagrees with recent EFT calculations that were performed within the perturbative scheme proposed by Kaplan,Savage,and Wise.Possible reasons for the difference are discussed.展开更多
Weakly bound states often occur in nuclear physics.To precisely understand their properties,the coupling to the continuum should be worked out explicitly.As the first step,we use a simple nuclear model in the continuu...Weakly bound states often occur in nuclear physics.To precisely understand their properties,the coupling to the continuum should be worked out explicitly.As the first step,we use a simple nuclear model in the continuum and on a lattice to investigate the influence of a third particle on a loosely bound state of a particle and a heavy core.Our approach is consistent with the Lüscher formalism.展开更多
based on our analysis of the contributions from the connected and disconnected contraction diagrams to the pion-kaon scattering amplitude,we provide the first determination of the only free low-energy constant at O(p^...based on our analysis of the contributions from the connected and disconnected contraction diagrams to the pion-kaon scattering amplitude,we provide the first determination of the only free low-energy constant at O(p^(4)),known as L_(0)^(r),in SU(4|1)Partially-Quenched Chiral Perturbation theory using the data from the Extended Twisted Mass collaboration,L_(0)^(r)(μ=M_(ρ))=0.77(20)(25)(7)(7)(2)·10^(-3).The theory uncertainties originate from the unphysical scattering length,the physical low-energy constants,the higher-order chiral corrections,the(lattice)meson masses and the pion decay constant,respectively.展开更多
We calculate the energy levels corresponding to the Roper resonance based on a two-flavor chiral effective Lagrangian for pions,nucleons,deltas,and the Roper resonance at the leading one-loop order.We show that the Ro...We calculate the energy levels corresponding to the Roper resonance based on a two-flavor chiral effective Lagrangian for pions,nucleons,deltas,and the Roper resonance at the leading one-loop order.We show that the Roper mass can be extracted from these levels for lattice volumes of moderate size.展开更多
Many measurements of B decays involve admixtures of B hadrons. Previously we arbitrarily included such admixtures in the B±section, but because of their importance we have created two new sections:
The Review summarizes much of particle physics and cosmology. Using data from previous editions, plus 3,283 new measurements from 899 papers, we list, evaluate, and average measured properties of gauge bosons and the ...The Review summarizes much of particle physics and cosmology. Using data from previous editions, plus 3,283 new measurements from 899 papers, we list, evaluate, and average measured properties of gauge bosons and the recently discovered Higgs boson, leptons, quarks, mesons, and baryons. We summarize searches for hypothetical particles such as heavy neutrinos, supersymmetric and technicolor particles, axions, dark photons, etc. All the particle properties and search limits are listed in Summary Tables. We also give numerous tables, figures, formulae, and reviews of topics such as Supersymmetry, Extra Dimensions, Particle Detectors, Probability, and Statistics. Among the 112 reviews are many that are new or heavily revised including those on: Dark Energy, Higgs Boson Physics, Electroweak Model, Neutrino Cross Section Measurements, Monte Carlo Neutrino Generators, Top Quark, Dark Matter, Dynamical Electroweak Symmetry Breaking, Accelerator Physics of Colliders, High-Energy Collider Parameters, Big Bang Nucleosynthesis, Astrophysical Constants and Cosmological Parameters. A booklet is available containing the Summary Tables and abbreviated versions of some of the other sections of this full Review. All tables, listings, and reviews (and errata) are also available on the Particle Data Group website: http ://pdg. lbl. gov.展开更多
Written by R.L. Kelly (LBNL). The most commonly used SU(3) isoscalar factors, corresponding to the singlet, octet, and deeuplet content of 8 8 and 10 8, are shown at the right. The notation uses particle nam...Written by R.L. Kelly (LBNL). The most commonly used SU(3) isoscalar factors, corresponding to the singlet, octet, and deeuplet content of 8 8 and 10 8, are shown at the right. The notation uses particle names to identify the coefficients, so that the pattern of relative couplings may be seen at a glance. We illustrate the use of the coefficients below.展开更多
Revised August 2013 by M.J. Syphers (MSU) and F. Zimmermann (CERN).29.1. Luminosity This article provides background for the High-Energy Collider Parameter Tables that follow. The number of events, Nexp, is the pr...Revised August 2013 by M.J. Syphers (MSU) and F. Zimmermann (CERN).29.1. Luminosity This article provides background for the High-Energy Collider Parameter Tables that follow. The number of events, Nexp, is the product of the cross section of interest,展开更多
Table 6.1 Abridged from pdg. ibl.gov/AtomicNuclearProperties by D. E. Groom (2007). See web pages for more detail about entries in this table including chemical formulae, and for several hundred other entries. Quant...Table 6.1 Abridged from pdg. ibl.gov/AtomicNuclearProperties by D. E. Groom (2007). See web pages for more detail about entries in this table including chemical formulae, and for several hundred other entries. Quantities in parentheses are for gases at 20℃ and 1 atm, and square brackets indicate evaluation at 0℃ and 1 atm. Boiling points are at 1 atm.展开更多
1. IntroductionThe collection of online information resources in particle physics and related areas presented in this chapter is of necessity incomplete. An expanded and regularly updated online version can be found at:
Magnetic Monopole SearchesIsolated supermassive monopole candidate events have not been confirmed. The most sensitive experiments obtain negative results.
Revised September 2013 by T. Damour (IHES, Bures-sur-Yvette, France). Einstein's General Relativity, the current "standard" theory of gravitation, describes gravity as a universal deformation of the Minkowski me...Revised September 2013 by T. Damour (IHES, Bures-sur-Yvette, France). Einstein's General Relativity, the current "standard" theory of gravitation, describes gravity as a universal deformation of the Minkowski metric:展开更多
See "The International System of Units (SI)," NIST Special Publication 330, B.N. Taylor, ed. (USGPO, Washington, DC, 1991); and "Guide for the Use of the International System of Units (SI)," NIST Special Pub...See "The International System of Units (SI)," NIST Special Publication 330, B.N. Taylor, ed. (USGPO, Washington, DC, 1991); and "Guide for the Use of the International System of Units (SI)," NIST Special Publication 811, 1995 edition, B.N. Taylor (USGPO, Washington, DC, 1995).展开更多
Updated 2013 (see the various sections for authors).34.1. Introduction Non-accelerator experiments have become increasingly important in particle physics. These include classical cosmic ray experiments, neutrino osc...Updated 2013 (see the various sections for authors).34.1. Introduction Non-accelerator experiments have become increasingly important in particle physics. These include classical cosmic ray experiments, neutrino oscillation measurements, and searches for double-beta decay, dark matter candidates, and magnetic monopoles.展开更多
基金supported in part by the National Natural Science Foundation of China(NSFC)the Deutsche Forschungsgemeinschaft(DFG)through the funds provided to the Sino-German Collaborative Research Center TRR110‘Symmetries and the Emergence of Structure in QCD’(NSFC Grant No.12070131001,DFG Project-ID 196253076)+3 种基金the Chinese Academy of Sciences(CAS)under Grant No.XDB34030000the NSFC under Grants Nos.12125507,11835015,and 12047503CAS through the President’s International Fellowship Initiative(PIFI)(Grant No.2018DM0034)the Volkswagen Stiftung(Grant No.93562)
文摘The internal structure of the charm-strange mesons D_(s0)^(*)(2317)and D_(s1)(2460)are the subject of intensive studies.Their widths are small because they decay dominantly through isospinbreaking hadronic channels D_(s0)^(*)(2317)^(+)→D_(s)^(+)π^(0) and D _(s1)(2460)^(+)→D_(s)^(*+)π^(0).The D_(s1)(2460)can also decay into the hadronic final states D_(s)^(+)ππ,conserving isospin.In that case there is,however,a strong suppression from phase space.We study the transition D_(s1)(2460)^(+)→D_(s)^(+)π^(+)π^(-)in the scenario that the D_(s1)(2460)is a D^(*)K hadronic molecule.The ππ final state interaction is taken into account through dispersion relations.We find that the ratio of the partial widths of the Γ(D_(s1)(2460)^(+)→D_(s)^(+)π^(+)π^(-)) / Γ(D_(s1)(2460)^(+)→D_(s)^(*+)π^(0))obtained in the molecular picture is consistent with the existing experimental measurement.More interestingly,we demonstrate that theπ+π−invariant mass distribution shows a double bump structure,which can be used to disentangle the hadronic molecular picture from the compact state picture for the D_(s1)(2460)^(+).Predictions on the B_(s1)^(0)→B_(s)^(0)π^(+)π^(-)are also made.
基金Supported by the Spanish Excellence Network on Hadronic Physics FIS2014-57026-REDTby Spanish Grants Universidad Complutense UCM:910309 and Ministerio de Economiay Competitividad MINECO:FPA2011-27853-C02-01+2 种基金MINECO:FPA2014-53375-C2-1-Pby the Deutsche Forschungsgemeinschaft and National Natural Science Foundation of China through Funds Provided to the Sino-German CRC110 "Symmetries and the Emergence of Structure in QCD"(NSFC Grant No.11261130311)by NSFC(Grant No.11165005)
文摘We are exploring a generic strongly-interacting Electroweak Symmetry Breaking Sector(EWSBS) with the low-energy effective field theory for the four experimentally known particles(W_L~±,Z_l,h) and its dispersion-relation based unitary extension.In this contribution we provide simple estimates for the production cross-section of pairs of the EWSBS bosons and their resonances at proton-proton colliders as well as in a future e^-e^+(or potentially aμ^-μ^+) collider with a typical few-TeV energy.We examine the simplest production mechanisms,tree-level production through a W(dominant when quantum numbers allow) and the simple effective boson approximation(in which the electroweak bosons are considered as collinear partons of the colliding fermions).We exemplify with custodial isovector and isotensor resonances at 2 TeV,the energy currently being discussed because of a slight excess in the ATLAS 2-jet data.We find it hard,though not unthinkable,to ascribe this excess to one of these W_lW_l rescattering resonances.An isovector resonance could be produced at a rate smaller than,but close to earlier CMS exclusion bounds,depending on the parameters of the effective theory.The ZZ excess is then problematic and requires additional physics(such as an additional scalar resonance).The isotensor one(that would describe all charge combinations) has smaller cross-section.
基金supported in part by the DFG and the NSFC through funds provided to the Sino-German CRC 110"Symmetries and the Emergence of Structure in QCD"(DFG grant.no.TRR 110)the VolkswagenStiftung(93562)supported in part by The Chinese Academy of Sciences(CAS)President’s International Fellowship Initiative(PIFI)(2018DM0034)
文摘Neutron-antineutron(n−n)oscillations in the deuteron are considered.Specifically,the deuteron lifetime is calculated in terms of the free-space n−n oscillation time τn−n based on NN and NN interactions derived within chiral effective field theory(EFT).This results in(2.6±0.1)×10^22τ2^n−n s,which is close to the value obtained by Dover and collaborators more than three decades ago,but disagrees with recent EFT calculations that were performed within the perturbative scheme proposed by Kaplan,Savage,and Wise.Possible reasons for the difference are discussed.
基金financial support from the Deutsche Forschungsgemeinschaft (SFB/TRR 110,"Symmetries and the Emergence of Structure in QCD",grant no. TRR 110)by the Chinese Academy of Sciences (CAS) President’s International Fellowship Initiative (PIFI)(2018DM0034)+1 种基金by Volkswagen Stiftung (93562)by the Fundamental Research Funds for the Central Universities
文摘Weakly bound states often occur in nuclear physics.To precisely understand their properties,the coupling to the continuum should be worked out explicitly.As the first step,we use a simple nuclear model in the continuum and on a lattice to investigate the influence of a third particle on a loosely bound state of a particle and a heavy core.Our approach is consistent with the Lüscher formalism.
基金supported in part by the DFG(Projektnummer 196253076—TRR 110)the NSFC(Grant No.11621131001)through the funds provided to the Sino-German CRC 110‘Symmetries and the Emergence of Structure in QCD’+3 种基金by the Alexander von Humboldt Foundation through the Humboldt Research Fellowshipby the Chinese Academy of Sciences(CAS)through a President’s International Fellowship Initiative(PIFI)(Grant No.2018DM0034)by the Volkswagen Stiftung(Grant No.93562)by the EU Horizon 2020 research and innovation programme,STRONG-2020 project under grant agreement No.824093。
文摘based on our analysis of the contributions from the connected and disconnected contraction diagrams to the pion-kaon scattering amplitude,we provide the first determination of the only free low-energy constant at O(p^(4)),known as L_(0)^(r),in SU(4|1)Partially-Quenched Chiral Perturbation theory using the data from the Extended Twisted Mass collaboration,L_(0)^(r)(μ=M_(ρ))=0.77(20)(25)(7)(7)(2)·10^(-3).The theory uncertainties originate from the unphysical scattering length,the physical low-energy constants,the higher-order chiral corrections,the(lattice)meson masses and the pion decay constant,respectively.
基金DFG and NSFC through funds provided to the Sino-German CRC 110’Symmetries and the Emergence of Structure in QCD’(NSFC Grant No.11621131001,DFG Grant No.TRR110)Volkswagen Stiftung(Grant no.93562)the CAS President’s International Fellowship Initiative(PIFI)(Grant No.2018DM0034)。
文摘We calculate the energy levels corresponding to the Roper resonance based on a two-flavor chiral effective Lagrangian for pions,nucleons,deltas,and the Roper resonance at the leading one-loop order.We show that the Roper mass can be extracted from these levels for lattice volumes of moderate size.
文摘Many measurements of B decays involve admixtures of B hadrons. Previously we arbitrarily included such admixtures in the B±section, but because of their importance we have created two new sections:
基金supported by the Director,Office of Science,Office of High Energy Physics of the U.S.Department of Energy under Contract No.DE-AC02-05CH11231the U.S.National Science Foundation under Agreement No.PHY-0652989+3 种基金the European Laboratory for Particle Physics(CERN)an implementing arrangement between the governments of Japan(MEXT:Ministry of Education,Culture,Sports,Science and Technology)and the United States(DOE)on cooperative research and developmentthe Italian National Institute of Nuclear Physics(INFN)B.C.F.was supported by the U.S.National Science Foundation Grant PHY-1214082
文摘The Review summarizes much of particle physics and cosmology. Using data from previous editions, plus 3,283 new measurements from 899 papers, we list, evaluate, and average measured properties of gauge bosons and the recently discovered Higgs boson, leptons, quarks, mesons, and baryons. We summarize searches for hypothetical particles such as heavy neutrinos, supersymmetric and technicolor particles, axions, dark photons, etc. All the particle properties and search limits are listed in Summary Tables. We also give numerous tables, figures, formulae, and reviews of topics such as Supersymmetry, Extra Dimensions, Particle Detectors, Probability, and Statistics. Among the 112 reviews are many that are new or heavily revised including those on: Dark Energy, Higgs Boson Physics, Electroweak Model, Neutrino Cross Section Measurements, Monte Carlo Neutrino Generators, Top Quark, Dark Matter, Dynamical Electroweak Symmetry Breaking, Accelerator Physics of Colliders, High-Energy Collider Parameters, Big Bang Nucleosynthesis, Astrophysical Constants and Cosmological Parameters. A booklet is available containing the Summary Tables and abbreviated versions of some of the other sections of this full Review. All tables, listings, and reviews (and errata) are also available on the Particle Data Group website: http ://pdg. lbl. gov.
文摘Written by R.L. Kelly (LBNL). The most commonly used SU(3) isoscalar factors, corresponding to the singlet, octet, and deeuplet content of 8 8 and 10 8, are shown at the right. The notation uses particle names to identify the coefficients, so that the pattern of relative couplings may be seen at a glance. We illustrate the use of the coefficients below.
文摘Revised August 2013 by M.J. Syphers (MSU) and F. Zimmermann (CERN).29.1. Luminosity This article provides background for the High-Energy Collider Parameter Tables that follow. The number of events, Nexp, is the product of the cross section of interest,
文摘Table 6.1 Abridged from pdg. ibl.gov/AtomicNuclearProperties by D. E. Groom (2007). See web pages for more detail about entries in this table including chemical formulae, and for several hundred other entries. Quantities in parentheses are for gases at 20℃ and 1 atm, and square brackets indicate evaluation at 0℃ and 1 atm. Boiling points are at 1 atm.
文摘1. IntroductionThe collection of online information resources in particle physics and related areas presented in this chapter is of necessity incomplete. An expanded and regularly updated online version can be found at:
文摘Magnetic Monopole SearchesIsolated supermassive monopole candidate events have not been confirmed. The most sensitive experiments obtain negative results.
文摘Revised September 2013 by T. Damour (IHES, Bures-sur-Yvette, France). Einstein's General Relativity, the current "standard" theory of gravitation, describes gravity as a universal deformation of the Minkowski metric:
文摘See "The International System of Units (SI)," NIST Special Publication 330, B.N. Taylor, ed. (USGPO, Washington, DC, 1991); and "Guide for the Use of the International System of Units (SI)," NIST Special Publication 811, 1995 edition, B.N. Taylor (USGPO, Washington, DC, 1995).
文摘Updated 2013 (see the various sections for authors).34.1. Introduction Non-accelerator experiments have become increasingly important in particle physics. These include classical cosmic ray experiments, neutrino oscillation measurements, and searches for double-beta decay, dark matter candidates, and magnetic monopoles.