{
  "abstract": "We study the quasi-two-body decays $B_c^+ \\to χ_{c0,c1} [ρ(K^*) \\to] π^+π^0(K^0π^+)$ in the perturbative QCD framework at leading order. The $ππ$ and $Kπ$ pairs are produced via the P-wave resonances $ρ(770)$, $ρ(1450)$, $ρ(1700)$, and $K^*(892)$, parametrized by the Gounaris-Sakurai and relativistic Breit-Wigner models. The $ρ$ channels, dominated by the $ρ(770)$ resonance, yield $\\mathcal{B}(B_c^+ \\to χ_{c0} π^+π^0) = 7.33 \\times 10^{-4}$ and $\\mathcal{B}(B_c^+ \\to χ_{c1} π^+π^0) = 1.02 \\times 10^{-3}$, with constructive $ρ$ interference making the coherent total $\\sim 26\\%$--$30\\%$ larger than the $ρ(770)$ contribution alone. The Cabibbo-suppressed $Kπ$ channels yield branching ratios roughly a factor of five below those of the $ππ$ modes, $\\mathcal{B}(B_c^+ \\to χ_{c0} K^0π^+) = 1.49 \\times 10^{-4}$ and $\\mathcal{B}(B_c^+ \\to χ_{c1} K^0π^+) = 1.94 \\times 10^{-4}$, the Cabibbo suppression being only partially compensated by the narrow $K^*(892)$ resonance and the normalization factor $N_{K^*}=1.48$. For $χ_{c1}$ modes, $f_L \\approx 93\\%$ dominates and decreases with increasing resonance mass. The ratio $R_{χ_{c1}/χ_{c0}}^{ππ} \\approx 1.38$ reflects the common resonant $ρ$ production mechanism shared by $χ_{c0}$ and $χ_{c1}$, with the charmonium decay-constant hierarchy and phase space determining the relative yield of P-wave charmonia. The analogous ratio in the Cabibbo-suppressed $Kπ$ channel, $R_{χ_{c1}/χ_{c0}}^{Kπ} \\approx 1.30$, is consistent with this value, confirming that the spin ratio is governed by charmonium-side dynamics.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2607.23163",
  "author_total": 2,
  "authors": [
    {
      "name": "Jun Deng"
    },
    {
      "name": "Xian-Qiao Yu"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/crs72g33r5htx.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2607.23163",
  "fulltext_url": null,
  "id": "crs72g33r5htx",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2607.23163",
  "language": null,
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "http://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "hep-ph"
    ],
    [
      "openalex",
      "3106|Particle physics theoretical and experimental studies"
    ]
  ],
  "openalex": "W7171508434",
  "pdf_url": "https://arxiv.org/pdf/2607.23163",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-03",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/crs72g33r5htx.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:18:31Z",
      "native_id": "2607.23163",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2607.23163"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:hep-ph",
      "subfield": "high-energy"
    }
  ],
  "title": "Quasi-two-body decays $B_c^+ \\to χ_{c0,c1} [ρ(K^*) \\to] ππ(Kπ)$ in the PQCD approach",
  "title_text": "Quasi-two-body decays B_c^+ → χ_c0,c1 [ρ(K^*) →] ππ(Kπ) in the PQCD approach",
  "type": "preprint",
  "updated_at": "2026-10-30T12:18:31Z",
  "url": "https://research.draconitic.com/paper/crs72g33r5htx",
  "venue": "arXiv",
  "versions": []
}