Observation of a new baryon state in the Λb0π+π−$$ {\Lambda}_{\mathrm{b}}^0{\pi}^{+}{\pi}^{-} $$ mass spectrum
Name
13130_2020_Article_13234.pdf
Size
782.6 KB
Format
Adobe PDF
Checksum (MD5)
dffbdce6c662f43e2ca3f35e6ffffd9a
Author(s)
Aaij, R.
Abellán Beteta, C.
Ackernley, T.
Adeva, B.
Adinolfi, M.
Afsharnia, H.
Aidala, C. A
Aiola, S.
Ajaltouni, Z.
Akar, S.
Date Issued
June 23, 2020
Publisher
Springer Berlin Heidelberg
Citation
Journal of High Energy Physics. 2020 Jun 23;2020(6):136
Version
Final published version
Abstract
Abstract
A new baryon state is observed in the Λb0π+π−$$ {\Lambda}_{\mathrm{b}}^0{\pi}^{+}{\pi}^{-} $$ mass spectrum with high significance using a data sample of pp collisions, collected with the LHCb detector at centre-of-mass energies s$$ \sqrt{s} $$ = 7, 8 and 13 TeV, corresponding to an integrated luminosity of 9 fb−1. The mass and natural width of the new state are measured to be
m
=
6072.3
±
2.9
±
0.6
±
0.2
MeV
,
Γ
=
72
±
11
±
2
MeV
,
$$ {\displaystyle \begin{array}{l}m=6072.3\pm 2.9\pm 0.6\pm 0.2\ \mathrm{MeV},\\ {}\Gamma =72\pm 11\pm 2\ \mathrm{MeV},\end{array}} $$
where the first uncertainty is statistical and the second systematic. The third uncertainty for the mass is due to imprecise knowledge of the Λb0$$ {\Lambda}_{\mathrm{b}}^0 $$ baryon mass. The new state is consistent with the first radial excitation of the Λb0$$ {\Lambda}_{\mathrm{b}}^0 $$ baryon, the Λb(2S)0 resonance. Updated measurements of the masses and the upper limits on the natural widths of the previously observed Λb(5912)0 and Λb(5920)0 states are also reported.
MIT Department
Massachusetts Institute of Technology. Department of Physics
Terms of Use
Creative Commons Attribution
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1007/JHEP06(2020)136
