{
  "id": "1509.01789",
  "version": "v1",
  "published": "2015-09-06T09:38:56.000Z",
  "updated": "2015-09-06T09:38:56.000Z",
  "title": "Binding energy of the $X(3872)$ at unphysical pion masses",
  "authors": [
    "V. Baru",
    "E. Epelbaum",
    "A. A. Filin",
    "J. Gegelia",
    "A. V. Nefediev"
  ],
  "comment": "24 pages, 4 figures",
  "categories": [
    "hep-ph"
  ],
  "abstract": "Chiral extrapolation of the $X(3872)$ binding energy is investigated using the modified Weinberg formulation of chiral effective field theory for the $D \\bar{D}^*$ scattering. Given its explicit renormalisability, this approach is particularly useful to explore the interplay of the long- and short-range $D \\bar{D}^*$ forces in the $X(3872)$ from studying the light-quark (pion) mass dependence of its binding energy. In particular, the parameter-free leading-order calculation shows that the $X$-pole disappears for unphysical large pion masses. On the other hand, without contradicting the naive dimensional analysis, the higher-order pion-mass-dependent contact interaction can change the slope of the binding energy at the physical point yielding the opposite scenario of a stronger bound $X$ at pion masses larger than its physical value. An important role of the pion dynamics and of the 3-body $D\\bar{D}\\pi$ effects for chiral extrapolations of the $X$-pole is emphasised. The results of the present study should be of practical value for the lattice simulations since they provide a non-trivial connection between lattice points at unphysical pion masses and the physical world.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2015-09-06T09:38:56.000Z"
    }
  ],
  "analyses": {
    "subjects": [
      "14.40.Rt",
      "11.55.Bq",
      "12.38.Lg",
      "13.75.Lb"
    ],
    "keywords": [
      "unphysical pion masses",
      "binding energy",
      "chiral extrapolation",
      "higher-order pion-mass-dependent contact interaction",
      "chiral effective field theory"
    ],
    "publication": {
      "doi": "10.1103/PhysRevD.92.114016"
    },
    "note": {
      "typesetting": "TeX",
      "pages": 24,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 1392033
    }
  }
}