Yamagata-Sekihara, J., Cabrera, D., Vicente Vacas, M. J., & Hirenzaki, S. (2010). Formation of phi Mesic Nuclei. Prog. Theor. Phys., 124(1), 147–162.
Abstract: We consider the structure and formation of the phi mesic nuclei to investigate the experimental feasibility of the observation of signals of the phi mesic nucleus formation. phi mesic nuclei are considered to be very important objects to study the in-medium modification of the phi-meson spectral function at finite density. We consider ((p) over bar, phi), (gamma, p) and (pi(-), n) reactions to produce a phi-meson inside the nucleus and evaluate the effects of its medium modifications to the reaction cross sections. We also estimate the consequences of the uncertainties of the in-medium (K) over bar self-energy to the phi-nucleus interaction. We find that it may be possible to see peak structures in the reaction spectra for the strong attractive potential cases. On the other hand, for strong absorptive interaction cases with relatively weak attraction, it is very difficult to observe clear peaks and we may need to know the spectrum shape in a wide energy region to deduce the properties of phi.
|
Hiller Blin, A. N., Ledwig, T., & Vicente Vacas, M. J. (2015). Chiral dynamics in the (gamma)over-right-arrowp -> p pi(0) reaction. Phys. Lett. B, 747, 217–222.
Abstract: We investigate the neutral pion photoproduction on the proton near threshold in covariant chiral perturbation theory with the explicit inclusion of A degrees of freedom. This channel is specially sensitive to chiral dynamics and the advent of very precise data from the Mainz microtron has shown the limits of the convergence of the chiral series for both the heavy baryon and the covariant approaches. We show that the inclusion of the Delta resonance substantially improves the convergence leading to a good agreement with data for a wider range of energies.
|
Ren, X. L., Alvarez-Ruso, L., Geng, L. S., Ledwig, T., Meng, J., & Vicente Vacas, M. J. (2017). Consistency between SU(3) and SU(2) covariant baryon chiral perturbation theory for the nucleon mass. Phys. Lett. B, 766, 325–333.
Abstract: Treating the strange quark mass as a heavy scale compared to the light quark mass, we perform a matching of the nucleon mass in the SU(3) sector to the two-flavor case in covariant baryon chiral perturbation theory. The validity of the 19low-energy constants appearing in the octet baryon masses up to next-to-next-to-next-to-leading order[1] is supported by comparing the effective parameters (the combinations of the 19couplings) with the corresponding low-energy constants in the SU(2) sector[2]. In addition, it is shown that the dependence of the effective parameters and the pion-nucleon sigma term on the strange quark mass is relatively weak around its physical value, thus providing support to the assumption made in Ref.[2] that the SU(2) baryon chiral perturbation theory can be applied to study n(f) = 2 + 1lattice QCD simulations as long as the strange quark mass is close to its physical value.
|
Sarkar, S., Sun, B. X., Oset, E., & Vicente Vacas, M. J. (2010). Dynamically generated resonances from the vector octet-baryon decuplet interaction. Eur. Phys. J. A, 44(3), 431–443.
Abstract: We study the interaction of the octet of vector mesons with the decuplet of baryons using Lagrangians of the hidden gauge theory for vector interactions. The unitary amplitudes in coupled channels develop poles that can be associated with some known baryonic resonances, while there are predictions for new ones at the energy frontier of the experimental research. The work offers guidelines on how to search for these resonances.
|
Rafi Alam, M., Ruiz Simo, I., Sajjad Athar, M., & Vicente Vacas, M. J. (2012). Antineutrino induced antikaon production off the nucleon. Phys. Rev. D, 85(1), 013014–8pp.
Abstract: The charged-current antikaon production off nucleons induced by antineutrinos is studied at low and intermediate energies. We extend here our previous calculation on kaon production induced by neutrinos. We have developed a microscopic model that starts from the SU(3) chiral Lagrangians and includes background terms and the resonant mechanisms associated to the lowest lying resonance in the channel, namely, the Sigma*(1385). Our results could be of interest for the background estimation of various neutrino oscillation experiments like MiniBooNE and SuperK. They can also be helpful for the planned (nu) over bar experiments like MINER nu A, NO nu A, and T2K phase II, and for beta-beam experiments with antineutrino energies around 1 GeV.
|
