Strange and charm mesons at FAIR

Presented at the XXXI Mazurian Lakes Conference on Physics, Piaski, Poland, August 30–September 6, 2009.

Interaction of vector mesons with baryons and vectors in the nuclear medium

In this talk we present a short review of recent developments concerning the interaction of vector mesons with baryons and with nuclei. We begin with the hidden gauge formalism for the interaction of vector mesons, then review results for vector baryon interaction and in particular the resonances which appear as composite states, dynamically generated from the interaction of vector mesons with baryons. New developments concerning the mixing of these states with pseudoscalars and baryons are also reported. We include some discussion on the $5/2^+$ $\Delta$ resonances around 2000 MeV, where we suggest that the $\Delta(2000)5/2^+$ resonance, which comes in the PDG from averaging a set of reson…

Determination of the compositeness of resonances from decays: The case of theBs0→J/ψf1(1285)

We develop a method to measure the amount of compositeness of a resonance, mostly made as a bound state of two hadrons, by simultaneously measuring the rate of production of the resonance and the mass distribution of the two hadrons close to threshold. By using different methods of analysis we conclude that the method allows one to extract the value of 1-Z with about 0.1 of uncertainty. The method is applied to the case of the ${\overline{B}}_{s}^{0}\ensuremath{\rightarrow}J/\ensuremath{\psi}{f}_{1}(1285)$ decay, by looking at the resonance production and the mass distribution of $K{\overline{K}}^{*}$.

Scalar, axial-vector, and tensor resonances from the rho D-*, omega D-* interaction in the hidden gauge formalism

13 pages, 15 figures.-- PACS nrs.: 13.75.Lb, 12.40.Vv, 12.40.Yx, 14.40.Cs.-- ArXiv pre-print available at: http://arxiv.org/abs/0903.3823

Prediction of Narrow N* and Lambda* Resonances with Hidden Charm above 4 GeV

The interaction between various charmed mesons and charmed baryons are studied within the framework of the coupled channel unitary approach with the local hidden gauge formalism. Several meson-baryon dynamically generated narrow $N^*$ and $\Lambda^*$ resonances with hidden charm are predicted with mass above 4 GeV and width smaller than 100 MeV. The predicted new resonances definitely cannot be accommodated by quark models with three constituent quarks and can be looked for at the forthcoming PANDA/FAIR experiments.

On the chiral covariant approach to ρρ scattering

We examine in detail a recent work (D.~G\"ulmez, U.-G.~Mei\ss ner and J.~A.~Oller, Eur. Phys. J. C 77:460 (2017)), where improvements to make $\rho\rho$ scattering relativistically covariant are made. The paper has the remarkable conclusion that the $J=2$ state disappears with a potential which is much more attractive than for $J=0$, where a bound state is found. We trace this abnormal conclusion to the fact that an "on-shell" factorization of the potential is done in a region where this potential is singular and develops a large discontinuous and unphysical imaginary part. A method is developed, evaluating the loops with full $\rho$ propagators, and we show that they do not develop singula…

Light- and strange-quark mass dependence of the ρ(770) meson revisited

Recent lattice data on $\pi\pi$-scattering phase shifts in the vector-isovector channel, pseudoscalar meson masses and decay constants for strange-quark masses smaller or equal to the physical value allow us to study the strangeness dependence of these observables for the first time. We perform a global analysis on two kind of lattice trajectories depending on whether the sum of quark masses or the strange-quark mass is kept fixed to the physical point. The quark mass dependence of these observables is extracted from unitarized coupled-channel one-loop Chiral Perturbation Theory. This analysis guides new predictions on the $\rho(770)$ meson properties over trajectories where the strange-qua…

Predictions for the $\bar B^0 \to \bar K^{*0} X (YZ)$ and $\bar B^0_s \to \phi X (YZ)$ with $X(4160), Y(3940), Z(3930)$

We investigate the decay of $\bar B^0 \to \bar K^{*0} R$ and $\bar B^0_s \to \phi R$ with $R$ being the $X(4160)$, $Y(3940)$, $Z(3930)$ resonances. Under the assumption that these states are dynamically generated from the vector-vector interaction, as has been concluded from several theoretical studies, we use a reaction mechanism of quark production at the elementary level, followed by hadronization of one final $q \bar q$ pair into two vectors and posterior final state interaction of this pair of vector mesons to produce the resonances. With this procedure we are able to predict five ratios for these decays, which are closely linked to the dynamical nature of these states, and also predic…

Prediction of new Tcc states of D*D* and Ds*D* molecular nature

Molecular picture for the (2866) as a = 0 State and Related 1 ,2 States

We recall the predictions made ten years ago about a bound state of JP=0+ in I=0 of the D⁎K¯⁎ system, which is manifestly exotic, and we associate it to the X0(2866) state reported in the recent LHCb experiment. Fine tuning the parameters to reproduce exactly the mass and width of the X0(2866) state, we report two more states stemming from the same interaction, one with 1+ and the other with 2+. For reasons of parity, the 1+ state cannot be observed in DK¯ decay, and we suggest to observe it in the D⁎K¯ spectrum. On the other hand, the 2+ state can be observed in DK¯ decay but the present experiment has too small statistics in the region of its mass to make any claim. We note that measureme…

Molecular picture for the $X_0(2866)$ as a $D^* \bar{K}^*$ $J^P=0^+$ state and related $1^+,2^+$ states

We recall the predictions made ten years ago about a bound state of $J^P=0^+$ in $I=0 $ of the $D^* \bar{K}^*$ system, which is manifestly exotic, and we associate it to the $X_0(2866)$ state reported in the recent LHCb experiment. Fine tuning the parameters to reproduce exactly the mass and width of the $X_0(2866)$ state, we report two more states stemming from the same interaction, one with $1^+$ and the other with $2^+$. For reasons of parity, the $1^+$ state cannot be observed in $D\bar{K}$ decay, and we suggest to observe it in the $D^*\bar{K}$ spectrum. On the other hand, the $2^+$ state can be observed in $D \bar{K}$ decay but the present experiment has too small statistics in the re…

Looking for the exotic X 0 ( 2866 ) and its J P = 1 + partner in the B ¯ 0 → D ( * ) + K − K ( * ) 0 reactions

Prediction of new T c c states of D * D * and D s * D * molecular nature

Sequential single pion production explaining the dibaryon "d*(2380)" peak*

We study the two step sequential one pion production mechanism, $np(I=0)\to \pi^-pp$, followed by the fusion reaction $pp\to \pi^+d$, in order to describe the $np\to \pi^+\pi^-d$ reaction with $\pi^+\pi^-$ in $I=0$, where a narrow peak, so far identified with a "$d(2380)$" dibaryon, has been observed. We find that the second step $pp\to \pi^+d$ is driven by a triangle singularity that determines the position of the peak of the reaction and the large strength of the cross section. The combined cross section of these two mechanisms produce a narrow peak with the position, width and strength compatible with the experimental observation within the approximations done. This novel interpretation …

Comments on the dispersion relation method to vector–vector interaction

We study in detail the method proposed recently to study the vector-vector interaction using the $N/D$ method and dispersion relations, which concludes that, while for $J=0$, one finds bound states, in the case of $J=2$, where the interaction is also attractive and much stronger, no bound state is found. In that work, approximations are done for $N$ and $D$ and a subtracted dispersion relation for $D$ is used, with subtractions made up to a polynomial of second degree in $s-s_\mathrm{th}$, matching the expression to $1-VG$ at threshold. We study this in detail for the $\rho - \rho$ interaction and to see the convergence of the method we make an extra subtraction matching $1-VG$ at threshold…

Looking for the exotic X0(2866) and its JP=1+ partner in the B¯0→D(*)+K−K(*)0 reactions

The Association of Intraoperative driving pressure with postoperative pulmonary complications in open versus closed abdominal surgery patients – a posthoc propensity score–weighted cohort analysis of the LAS VEGAS study

Abstract Background It is uncertain whether the association of the intraoperative driving pressure (ΔP) with postoperative pulmonary complications (PPCs) depends on the surgical approach during abdominal surgery. Our primary objective was to determine and compare the association of time–weighted average ΔP (ΔPTW) with PPCs. We also tested the association of ΔPTW with intraoperative adverse events. Methods Posthoc retrospective propensity score–weighted cohort analysis of patients undergoing open or closed abdominal surgery in the ‘Local ASsessment of Ventilatory management during General Anaesthesia for Surgery’ (LAS VEGAS) study, that included patients in 146 hospitals across 29 countries.…

A new interpretation for the $D^*_{s2}(2573)$ and the prediction of novel exotic charmed mesons

In this manuscript we study the vector - vector interaction within the hidden gauge formalism in a coupled channel unitary approach. In the sector $C=1,S=1,J=2$ we get a pole in the T-matrix around $2572$ MeV that we identify with the $D^*_{s2}(2573)$, coupling strongly to the $D^*K^*$($D^*_s\phi$($\omega$)) channels. In addition we obtain resonances in other exotic sectors which have not been studied before such as $C=1,S=-1$, $C=2,S=0$ and $C=2,S=1$. This 'flavor-exotic' states are interpreted as $D^*\bar{K^*}$, $D^*D^*$ and $D^*_sD^*$ molecular states but have not been observed yet. In total we obtain nine states with different spin, isospin, charm and strangeness of non $C=0,S=0$ and $C…

The Y(3940), Z(3930) and the X(4160) as dynamically generated resonances from the vector-vector interaction

We study the vector-vector interaction within the framework of the hidden gauge formalism for the sector with quantum numbers charm C=0 and strangeness S=0 in the region around 4000 MeV. We get five poles, three of which could be identified with the Y(3940), Z(3930) and X(4160). These poles appear with quantum numbers I=0 and $J^{PC}=0^{++},2^{++}$ and $2^{++}$, respectively, and can be considered as hadronic molecules made of $D^*\bar{D}^*$, $D_s^*\bar{D}^*_s$.

Strategies for an accurate determination of the X(3872) energy from QCD lattice simulations

We develop a method to determine accurately the binding energy of the X(3872) from lattice data for the DD* interaction. We show that, because of the small difference between the neutral and charged components of the X(3872), it is necessary to distinguish them in the energy levels of the lattice spectrum if one wishes to have a precise determination of the the binding energy of the X(3872). The analysis of the data requires the use of coupled channels. Depending on the number of levels available and the size of the box we determine the precision needed in the lattice energies to finally obtain a desired accuracy in the binding energy.