All-heavy pentaquarks

In a nonrelativistic quark model framework, we carry out a calculation of the mass spectrum for the low-lying <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mn>1</a:mn><a:mi>S</a:mi></a:math> all-heavy pentaquark states by adopting the explicitly correlated Gaussian method. The obtained states are compact and lie far above the lowest dissociation baryon-meson threshold. Moreover, using the obtained masses and wave functions we evaluate the fall-apart decay properties within a quark-exchange model. The results show that the <c:math xmlns:c="http://www.w3.org/1998/Math/MathML" display="inline"><c:mn>1</c:mn><c:mi>S</c:mi></c:math> all-heavy pentaquark states have a fairly narrow fall-apart width, which scatters in the range of <e:math xmlns:e="http://www.w3.org/1998/Math/MathML" display="inline"><e:mrow><e:mo>∼</e:mo><e:mn>0.1</e:mn><e:mi>–</e:mi><e:mn>4.0</e:mn><e:mtext> </e:mtext><e:mtext> </e:mtext><e:mi>MeV</e:mi></e:mrow></e:math>. Their dominant fall-apart decay channels may be ideal for searching for their signals in future experiments.