A search for rare $B \rightarrow D \mu^+ \mu^-$ decays

• Published in: The journal of high energy physics 2024, Vol.2
• Main Authors: Aaij, Roel, Abdelmotteleb, Ahmed Sameh Wagih, Abellan Beteta, Carlos, Abudinén, Fernando Jesus, Ackernley, Thomas, Adeva, Bernardo, Adinolfi, Marco, Adlarson, Patrik Harri, Afsharnia, Hossein, Agapopoulou, Christina, Aidala, Christine Angela, Ajaltouni, Ziad, Akar, Simon, Akiba, Kazuyoshi, Albicocco, Pietro, Albrecht, Johannes, Alessio, Federico, Alexander, Michael, Alfonso Albero, Alejandro, Aliouche, Zakariya, Alvarez Cartelle, Paula, Amalric, Renaud, Amato, Sandra, Amey, Jake Lewis, Amhis, Yasmine, An, Liupan, Anderlini, Lucio, Andersson, Martin, Andreianov, Aleksei, Andreotti, Mirco, Andreou, Dimitra, Ao, Dong, Archilli, Flavio, Artamonov, Alexander, Artuso, Marina, Aslanides, Elie, Atzeni, Michele, Audurier, Benjamin, Bachiller Perea, Irene, Bachmann, Sebastian, Bachmayer, Marie, Back, John, Bailly-Reyre, Aurelien, Baladron Rodriguez, Pablo, Balagura, Vladislav, Baldini, Wander, Baptista de Souza Leite, Juan, Barbetti, Matteo, Barlow, Roger, Barsuk, Sergey, Barter, William, Bartolini, Matteo, Baryshnikov, Fedor, Basels, Jan-Marc, Bassi, Giovanni, Batsukh, Baasansuren, Battig, Alexander, Bay, Aurelio, Beck, Anja, Becker, Maik, Bedeschi, Franco, Bediaga, Ignacio, Beiter, Andrew, Belin, Samuel, Bellee, Violaine, Belous, Konstantin, Belov, Ilia, Belyaev, Ivan, Benane, Gaya, Bencivenni, Giovanni, Ben-Haim, Eli, Berezhnoy, Alexander, Bernet, Roland, Bernet Andres, Sergi, Berninghoff, Daniel, Bernstein, Harris Conan, Bertella, Claudia, Bertolin, Alessandro, Betancourt, Christopher, Betti, Federico, Bezshyiko, Iaroslava, Bhom, Jihyun, Bian, Lingzhu, Bieker, Martin Stefan, Biesuz, Nicolo Vladi, Billoir, Pierre, Biolchini, Alice, Birch, Matthew, Bishop, Fionn Caitlin Ros, Bitadze, Alexander, Bizzeti, Andrea, Blago, Michele Piero, Blake, Thomas, Blanc, Frederic, Blank, Jonah Evan, Blusk, Steven, Bobulska, Dana, Bocharnikov, Vladimir, Boelhauve, Julian Alexander, Boente Garcia, Oscar
• Format: Article
• Language: English
• Subjects: High Energy Physics - Experiment; Physics
• ISSN: 1126-6708; 1029-8479
• DOI: 10.1007/JHEP02(2024)032

A search for rare $B \rightarrow D \mu^+ \mu^-$ decays is performed using proton-proton collision data collected by the LHCb experiment, corresponding to an integrated luminosity of 9 fb$^{-1}$. No significant signals are observed in the non-resonant $\mu^+\mu^-$ modes, and upper limits of $\mathcal{B}(B^0 \rightarrow \overline{D}^0 \mu^+ \mu^-) < 5.1 \times 10^{-8}$, $\mathcal{B}(B^+ \rightarrow D_s^+ \mu^+ \mu^-) < 3.2 \times 10^{-8}$, $\mathcal{B}(B_s^0 \rightarrow \overline{D}^0 \mu^+ \mu^-) < 1.6 \times 10^{-7}$ and $f_c/f_u \cdot \mathcal{B}(B_c^+ \rightarrow D_s^+ \mu^+ \mu^-) < 9.6 \times 10^{-8}$ are set at the 95% confidence level, where $f_c$ and $f_u$ are the fragmentation fractions of a $B$ meson with a $c$ and $u$ quark respectively in proton-proton collisions. Each result is either the first such measurement or an improvement by three orders of magnitude on an existing limit. Separate upper limits are calculated when the muon pair originates from a $J/\psi \rightarrow \mu^+ \mu^-$ decay. The branching fraction of $B_c^+ \rightarrow D_s^+ J/\psi$ multiplied by the fragmentation-fraction ratio is measured to be $f_c/f_u \cdot \mathcal{B}(B_c^+ \rightarrow D_s^+ J/\psi ) = (1.63 \pm 0.15 \pm 0.13) \times 10^{-5}$, where the first uncertainty is statistical and the second systematic.