# A Study of B→c$\bar{c}$γK in the BaBar Experiment

### Description

The BABAR Collaboration is a high energy physics experiment located at the Stanford Linear Accelerator Center. The primary goal of the experiment is to study charge and parity violation in the B-meson sector, however the copious production of B mesons decaying to other final states allows for a wide-ranging physics program. In particular, one can access the charmonium system via colour-suppressed b → c decays of the type B → c$\bar{c}$K. This thesis presents a study of B →c$\bar{c}$γK decays where c$\bar{c}$ includes J/Ψ and Ψ(2S), and K includes K<sup>±</sup>, K<sub>S</sub><sup>0</sup> and K*(892). The particular emphasis is on a search ... continued below

224 p.

### Creation Information

Fulsom, Brian Gregory April 1, 2009.

### Context

This thesis or dissertation is part of the collection entitled: Office of Scientific & Technical Information Technical Reports and was provided by UNT Libraries Government Documents Department to Digital Library, a digital repository hosted by the UNT Libraries. More information about this document can be viewed below.

## Who

People and organizations associated with either the creation of this thesis or dissertation or its content.

### Provided By

#### UNT Libraries Government Documents Department

Serving as both a federal and a state depository library, the UNT Libraries Government Documents Department maintains millions of items in a variety of formats. The department is a member of the FDLP Content Partnerships Program and an Affiliated Archive of the National Archives.

## What

Descriptive information to help identify this thesis or dissertation. Follow the links below to find similar items on the Digital Library.

### Description

The BABAR Collaboration is a high energy physics experiment located at the Stanford Linear Accelerator Center. The primary goal of the experiment is to study charge and parity violation in the B-meson sector, however the copious production of B mesons decaying to other final states allows for a wide-ranging physics program. In particular, one can access the charmonium system via colour-suppressed b → c decays of the type B → c$\bar{c}$K. This thesis presents a study of B →c$\bar{c}$γK decays where c$\bar{c}$ includes J/Ψ and Ψ(2S), and K includes K<sup>±</sup>, K<sub>S</sub><sup>0</sup> and K*(892). The particular emphasis is on a search for the radiative decays X(3872) → J/Ψγ and X(3872) → Ψ(2S)γ. The X(3872) state is a recently-discovered resonance of undetermined quark composition, speculatively a conventional charmonium state or exotic four-quark di-meson molecule. This research is also sensitive to the well-known radiative charmonium decays B → χ<sub>c1,2</sub>K, which are used as verification for the analysis technique. This dissertation sets the best B → χ<sub>c1</sub>K branching fraction measurements to date, and sees the first evidence for factorization-suppressed B<sup>0</sup> → χ<sub>c2</sub>}K*<sup>0</sup> decay at a level of 3.6σ. It also provides evidence for X(3872) → J/Ψγ and X(3872) → Ψ(2S)γ with 3.6σ and 3.3σ significance, respectively. The product of branching fractions β(B<sup>±</sup> → X(3872)K<sup>±</sup>) • β(X(3872) → J/Ψγ) = (2.8 ± 0.8(stat.) ± 0.2(syst.)) x 10{sup -6} and β(B{<sup>±</sup> → X(3872)K<sup>±</sup>) → β(X(3872) → Ψ(2S)γ) = (9.5 ± 2.7(stat.) ± 0.9(syst.)) x 10<sup>-</sup>6 are measured. These results improve upon previous X(3872) → J/Ψγ measurements, and represent the first evidence for X(3872) → Ψ(2S)γ.

224 p.

### Identifier

Unique identifying numbers for this document in the Digital Library or other systems.

• Report No.: SLAC-R--949
• Grant Number: AC02-76SF00515
• DOI: 10.2172/992973 | External Link
• Office of Scientific & Technical Information Report Number: 992973

### Collections

This document is part of the following collection of related materials.

#### Office of Scientific & Technical Information Technical Reports

Reports, articles and other documents harvested from the Office of Scientific and Technical Information.

Office of Scientific and Technical Information (OSTI) is the Department of Energy (DOE) office that collects, preserves, and disseminates DOE-sponsored research and development (R&D) results that are the outcomes of R&D projects or other funded activities at DOE labs and facilities nationwide and grantees at universities and other institutions.

What responsibilities do I have when using this thesis or dissertation?

## When

Dates and time periods associated with this thesis or dissertation.

### Creation Date

• April 1, 2009

### Added to The UNT Digital Library

• Oct. 14, 2017, 8:36 a.m.

### Description Last Updated

• Oct. 25, 2017, 4:33 p.m.

### Usage Statistics

Congratulations! It looks like you are the first person to view this item online.

## Interact With This Thesis Or Dissertation

Here are some suggestions for what to do next.

Fulsom, Brian Gregory. A Study of B→c$\bar{c}$γK in the BaBar Experiment, thesis or dissertation, April 1, 2009; United States. (digital.library.unt.edu/ark:/67531/metadc1013348/: accessed July 20, 2018), University of North Texas Libraries, Digital Library, digital.library.unt.edu; crediting UNT Libraries Government Documents Department.