{
  "id": "nucl-th/9906095",
  "version": "v2",
  "published": "1999-06-30T16:19:52.000Z",
  "updated": "1999-09-28T10:47:42.000Z",
  "title": "Relativistic effects on the neutron charge form factor in the constituent quark model",
  "authors": [
    "Fabio Cardarelli",
    "Silvano Simula"
  ],
  "comment": "final version with one minor correction and updated references; to appear in Physics Letters B",
  "journal": "Phys.Lett. B467 (1999) 1-7",
  "doi": "10.1016/S0370-2693(99)01146-6",
  "categories": [
    "nucl-th",
    "hep-ph"
  ],
  "abstract": "The neutron charge form factor GEn(Q**2) is investigated within a constituent quark model formulated on the light-front. It is shown that, if the quark initial motion is neglected in the Melosh rotations, the Dirac neutron form factor F1n(Q**2)$ receives a relativistic correction which cancels exactly against the Foldy term in GEn(Q**2), as it has been recently argued by Isgur. Moreover, at the same level of approximation the ratio of the proton to neutron magnetic form factors GMp(Q**2) / GMn(Q**2) is still given by the naive SU(6)-symmetry expectation, -3/2. However, it is also shown that the full Melosh rotations break SU(6) symmetry, giving rise to GEn(Q**2) =/ 0 and GMp(Q**2)/GMn(Q**2) =/ -3/2 even when a SU(6)-symmetric canonical wave function is assumed. It turns out that relativistic effects alone cannot explain simultaneously the experimental data on GEn(Q**2)$ and GMp(Q**2)/GMn(Q**2).",
  "revisions": [
    {
      "version": "v2",
      "updated": "1999-09-28T10:47:42.000Z"
    }
  ],
  "analyses": {
    "subjects": [
      "14.20.Dh",
      "13.40.Gp",
      "12.39.Ki",
      "14.65.Bt"
    ],
    "keywords": [
      "neutron charge form factor",
      "constituent quark model",
      "relativistic effects",
      "dirac neutron form factor",
      "quark initial motion"
    ],
    "tags": [
      "journal article"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 0,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 502801
    }
  }
}