The transverse charge density of pions is calculated based on relativistic quantum mechanics, where the pion is regarded as a quark-antiquark bound state. Corrections from the two spin-1/2 constituents and from the wa...The transverse charge density of pions is calculated based on relativistic quantum mechanics, where the pion is regarded as a quark-antiquark bound state. Corrections from the two spin-1/2 constituents and from the wave function of a quark and antiquark inside the bound system are discussed. The calculated results are compared to the results with a realistic effective Lagrangian approach as well as to that with a simple covariant model where the pion is regarded as a composite system with two scalar particles.展开更多
We revisit the compositeness theorem proposed by Weinberg in an effective field theory （EFT） and explore criteria which are sensitive to the structure of S-wave threshold states. On a general basis, we show that the...We revisit the compositeness theorem proposed by Weinberg in an effective field theory （EFT） and explore criteria which are sensitive to the structure of S-wave threshold states. On a general basis, we show that the wave function renormalization constant Z, which is the probability of finding an elementary component in the wave function of a threshold state, can be explicitly introduced in the description of the threshold state. As an application of this EFT method, we describe the near-threshold line shape of the D＊0D0 invariant mass spectrum in B→D＊0D-0K and determine a nonvanishing value of Z. It suggests that the X（3872） as a candidate of the D＊0D0 molecule may still contain a small cc core. This elementary component, on the one hand, explains its production in the B meson decay via a short-distance mechanism, and on the other hand, is correlated with the D＊0D0 threshold enhancement observed in the D＊0D0 invariant mass distributions. Meanwhile, we also show that if Z is non-zero, the near-threshold enhancement of the D＊0D0 mass spectrum in the B decay will be driven by the short-distance production mechanism.展开更多
Bowen Wang Trinity College Dublin,Dublin,From ut pictura poesis to intermediality,the close,interactive,and complicated relationship between poetry and painting has been an inevitable subject under discussion througho...Bowen Wang Trinity College Dublin,Dublin,From ut pictura poesis to intermediality,the close,interactive,and complicated relationship between poetry and painting has been an inevitable subject under discussion throughout the historiography of literature and fine art.Different approaches and interpretations to/on their sisterhood could come to a broad spectrum of interartistic ideas and practices.William Blake,an English Romantic poet,painter,and printmaker,links word and image by his invention of relief etching,or more understandably,the illuminated painting which juxtaposes his verse with in-text illustrations simultaneously on the same page.His technical strategy has already implied a dynamic and dialectical interrelation between word and image,like the treatment of earlier medieval manuscripts,yet in a more innovative rather than decorative manner.This article,therefore,through a comparative analysis of both Blake’s verbal and visual representations,will first attempt to clarify two distinct modes of combining poetic language with visualisation vis-à-vis form and content,and then critically investigate how this word-image interaction can be used to reflect the poet’s Romantic thought about sociocultural changes and provide new possibilities of reading,interpretation,and aesthetic complexity in that specific epoch.展开更多
Magnetic Monopole SearchesIsolated supermassive monopole candidate events have not been confirmed. The most sensitive experiments obtain negative results.
基金Supported by National Natural Science Foundation of China (10775148,10975146,11035006)
文摘The transverse charge density of pions is calculated based on relativistic quantum mechanics, where the pion is regarded as a quark-antiquark bound state. Corrections from the two spin-1/2 constituents and from the wave function of a quark and antiquark inside the bound system are discussed. The calculated results are compared to the results with a realistic effective Lagrangian approach as well as to that with a simple covariant model where the pion is regarded as a composite system with two scalar particles.
基金Supported by National Natural Science Foundation of China (11147022, 11035006, 11305137)Chinese Academy of Sciences (KJCX2EW-N01)+2 种基金Ministry of Science and Technology of China (2009CB825200)DFG and NSFC (11261130311) through funds provided to the Sino-German CRC 110 "Symmetries and the Emergence of Structure in QCD"Doctor Foundation of Xinjiang University (BS110104)
文摘We revisit the compositeness theorem proposed by Weinberg in an effective field theory （EFT） and explore criteria which are sensitive to the structure of S-wave threshold states. On a general basis, we show that the wave function renormalization constant Z, which is the probability of finding an elementary component in the wave function of a threshold state, can be explicitly introduced in the description of the threshold state. As an application of this EFT method, we describe the near-threshold line shape of the D＊0D0 invariant mass spectrum in B→D＊0D-0K and determine a nonvanishing value of Z. It suggests that the X（3872） as a candidate of the D＊0D0 molecule may still contain a small cc core. This elementary component, on the one hand, explains its production in the B meson decay via a short-distance mechanism, and on the other hand, is correlated with the D＊0D0 threshold enhancement observed in the D＊0D0 invariant mass distributions. Meanwhile, we also show that if Z is non-zero, the near-threshold enhancement of the D＊0D0 mass spectrum in the B decay will be driven by the short-distance production mechanism.
文摘Bowen Wang Trinity College Dublin,Dublin,From ut pictura poesis to intermediality,the close,interactive,and complicated relationship between poetry and painting has been an inevitable subject under discussion throughout the historiography of literature and fine art.Different approaches and interpretations to/on their sisterhood could come to a broad spectrum of interartistic ideas and practices.William Blake,an English Romantic poet,painter,and printmaker,links word and image by his invention of relief etching,or more understandably,the illuminated painting which juxtaposes his verse with in-text illustrations simultaneously on the same page.His technical strategy has already implied a dynamic and dialectical interrelation between word and image,like the treatment of earlier medieval manuscripts,yet in a more innovative rather than decorative manner.This article,therefore,through a comparative analysis of both Blake’s verbal and visual representations,will first attempt to clarify two distinct modes of combining poetic language with visualisation vis-à-vis form and content,and then critically investigate how this word-image interaction can be used to reflect the poet’s Romantic thought about sociocultural changes and provide new possibilities of reading,interpretation,and aesthetic complexity in that specific epoch.
文摘Magnetic Monopole SearchesIsolated supermassive monopole candidate events have not been confirmed. The most sensitive experiments obtain negative results.
