The quasi-fission phenomenon of double charm $$T_{cc}^+$$ induced by nucleon

Abstract

Abstract In this work, we study the reaction of a nucleon and a doubly charmed state $$T^+_{cc}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msubsup> <mml:mi>T</mml:mi> <mml:mrow> <mml:mi>cc</mml:mi> </mml:mrow> <mml:mo>+</mml:mo> </mml:msubsup> </mml:math> . Under the assumption of the $$T^+_{cc}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msubsup> <mml:mi>T</mml:mi> <mml:mrow> <mml:mi>cc</mml:mi> </mml:mrow> <mml:mo>+</mml:mo> </mml:msubsup> </mml:math> as a molecular state of $$D^{*}D$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:msup> <mml:mi>D</mml:mi> <mml:mrow> <mml:mrow/> <mml:mo>∗</mml:mo> </mml:mrow> </mml:msup> <mml:mi>D</mml:mi> </mml:mrow> </mml:math> , the reaction of the nucleon and $$T_{cc}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mi>T</mml:mi> <mml:mrow> <mml:mi>cc</mml:mi> </mml:mrow> </mml:msub> </mml:math> is mediated by exchanges of $$\pi $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>π</mml:mi> </mml:math> , $$\eta $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>η</mml:mi> </mml:math> , $$\rho $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>ρ</mml:mi> </mml:math> , and $$\omega $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>ω</mml:mi> </mml:math> meson, which results in split of $$T_{cc}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mi>T</mml:mi> <mml:mrow> <mml:mi>cc</mml:mi> </mml:mrow> </mml:msub> </mml:math> state with two D mesons in final state. With the help of the effective Lagrangians, the cross section of $$p+T^+_{cc}\rightarrow p+D^++D^0$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mi>p</mml:mi> <mml:mo>+</mml:mo> <mml:msubsup> <mml:mi>T</mml:mi> <mml:mrow> <mml:mi>cc</mml:mi> </mml:mrow> <mml:mo>+</mml:mo> </mml:msubsup> <mml:mo>→</mml:mo> <mml:mi>p</mml:mi> <mml:mo>+</mml:mo> <mml:msup> <mml:mi>D</mml:mi> <mml:mo>+</mml:mo> </mml:msup> <mml:mo>+</mml:mo> <mml:msup> <mml:mi>D</mml:mi> <mml:mn>0</mml:mn> </mml:msup> </mml:mrow> </mml:math> process is calculated, and a very large cross section can be obtained with very small incoming momentum of proton. It decrease rapidly with the increase of the momentum to about 10 mb at momenta of order of GeV. Such large cross section suggests that induced by a proton the $$T_{cc}^+$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msubsup> <mml:mi>T</mml:mi> <mml:mrow> <mml:mi>cc</mml:mi> </mml:mrow> <mml:mo>+</mml:mo> </mml:msubsup> </mml:math> state is very easy to decay and transit to two D mesons. In the rest frame of the $$T_{cc}^+$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msubsup> <mml:mi>T</mml:mi> <mml:mrow> <mml:mi>cc</mml:mi> </mml:mrow> <mml:mo>+</mml:mo> </mml:msubsup> </mml:math> state, an obvious accumulation of final D meson at small momentum region can be observed in predicted Dalitz plot, which is due to the molecular state interpretation of $$T^+_{cc}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msubsup> <mml:mi>T</mml:mi> <mml:mrow> <mml:mi>cc</mml:mi> </mml:mrow> <mml:mo>+</mml:mo> </mml:msubsup> </mml:math> state. This novel quasi-fission phenomenon of double charm molecular $$T_{cc}^+$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msubsup> <mml:mi>T</mml:mi> <mml:mrow> <mml:mi>cc</mml:mi> </mml:mrow> <mml:mo>+</mml:mo> </mml:msubsup> </mml:math> state induced by a proton can be accessible at High-Luminosity Large Hadron Collider.

Topics & Concepts