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BandQ: Sprucing - automatic line creation

Ivan Polyakov requested to merge bandq_ipolyako_hexa into master

Allows to semi-automatically create bunch of lines for:

  • detached B-> psi + hadrons (Nh<=4), where psi=J/psi, psi(2S), hadrons = pi, K, p, Ks, Lambda0, Xi-, Omega-; Very wide mass cut.
  • promptly produced X -> B + hadrons (Nh<=2), where B are from b_for_spectroscopy, either fully reconstructed (JpsiX,DX) or SemiLeptonic modes; M_combination < sum_M_daughters + 1*GeV;

For this one needs to declaring line names + decay descriptors manually:

auto_PsiX_lines[f"{psi_name}PiPi"] = [ f"[B_s0 -> {psi} pi+ pi-]cc", f"[B_s0 -> {psi} pi+ pi+]cc" ]
...
auto_BX_lines["BeautyPi"] = [ f"[ {BX_mother_id} -> B+ pi+]cc",
                              f"[ {BX_mother_id} -> B+ pi-]cc",
                              f"[ {BX_mother_id} -> B0 pi+]cc",
...
auto_BX_detached_lines["BcToBsPi"] = [ f"[ {BX_mother_id} -> B_s0 pi+]cc",
                                       f"[ {BX_mother_id} -> B_s0 pi-]cc" ]
...

then passing it to make_spruce_lines that will automatically create corresponding lines with standart code.

make_spruce_lines(
    make_fun=bx_prompt.make_BX_combination,
    line_dict=sprucing_lines,
    lines_to_add=auto_BX_lines)

Thus saving coding.

===============

in addition doing few improvements (may be separated in dedicated MR) in:

  • speed-up of make_b_hadrons via cuts on 12,123,... combinations - not important for J/psi h1 h2, but may be a big effect for J/psi h1 h2 h3 h4 lines, which we might want to create a lot.
  • minor fix in make_AllB in b_for_spectroscopy. It's currently not used, but just in case.
  • fix treatment of nopid option in longlived_hadrons - make it consistent with charged_hadrons.

==== small fact:

Firstly wanted to create few lines to search for hexa/penta-quarks with b-quark:

  • J/psi p+ p+ K-, J/psi p+ p+ K- pi-, J/psi p+ K+ pi-
  • and Lambda_b0 p+, Lambda_b0 Lambda0, Xi_b- p+, B0 p+

but instead decided to create something much more general.

https://gitlab.cern.ch/lhcb-dpa/project/-/issues/243

Edited by Alessandro Bertolin

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