Studies of $${\mathrm {B}} ^{*}_{{\mathrm {s}}2}(5840)^0 $$ Bs2∗(5840)0 and $${\mathrm {B}} _{{\mathrm {s}}1}(5830)^0 $$ Bs1(5830)0 mesons including the observation of the $${\mathrm {B}} ^{*}_{{\mathrm {s}}2}(5840)^0 \rightarrow {\mathrm {B}} ^0 \mathrm {K} ^0_{\mathrm {S}} $$ Bs2∗(5840)0→B0KS0 decay in proton-proton collisions at $$\sqrt{s}=8\,\text {TeV} $$ s=8TeV

Abstract

Abstract Measurements of $${\mathrm {B}} ^{*}_{{\mathrm {s}}2}(5840)^0 $$ Bs2∗(5840)0 and $${\mathrm {B}} _{{\mathrm {s}}1}(5830)^0 $$ Bs1(5830)0 mesons are performed using a data sample of proton-proton collisions corresponding to an integrated luminosity of , collected with the CMS detector at the LHC at a centre-of-mass energy of $$8\,\text {TeV} $$ 8TeV . The analysis studies P-wave $${\mathrm {B}} ^0_{\mathrm {s}} $$ Bs0 meson decays into $${\mathrm {B}} ^{(*)+} \mathrm {K} ^- $$ B(∗)+K- and $${\mathrm {B}} ^{(*)0} \mathrm {K} ^0_{\mathrm {S}} $$ B(∗)0KS0 , where the $${\mathrm {B}} ^+ $$ B+ and $${\mathrm {B}} ^0 $$ B0 mesons are identified using the decays $${\mathrm {B}} ^+ \rightarrow {\mathrm {J}}/\psi \mathrm {K} ^+ $$ B+→J/ψK+ and $${\mathrm {B}} ^0 \rightarrow {\mathrm {J}}/\psi \mathrm {K} ^{*}(892)^0 $$ B0→J/ψK∗(892)0 . The masses of the P-wave $${\mathrm {B}} ^0_{\mathrm {s}} $$ Bs0 meson states are measured and the natural width of the $${\mathrm {B}} ^{*}_{{\mathrm {s}}2}(5840)^0 $$ Bs2∗(5840)0 state is determined. The first measurement of the mass difference between the charged and neutral $${\mathrm {B}} ^{*} $$ B∗ mesons is also presented. The $${\mathrm {B}} ^{*}_{{\mathrm {s}}2}(5840)^0 $$ Bs2∗(5840)0 decay to $${\mathrm {B}} ^0 \mathrm {K} ^0_{\mathrm {S}} $$ B0KS0 is observed, together with a measurement of its branching fraction relative to the $${\mathrm {B}} ^{*}_{{\mathrm {s}}2}(5840)^0 \rightarrow {\mathrm {B}} ^+ \mathrm {K} ^- $$ Bs2∗(5840)0→B+K- decay.

Keywords

• CMS
• Physics
• b hadrons
• Heavy flavour spectroscopy
• Hadron spectroscopy
• Experimental results