Violation in Mixing
Violation in Mixing
Violation in Mixing
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7.7 The maximum likelihood analysis 177<br />
Parameter Run 1 Breco Run 2 Breco MC Breco<br />
Scale (core) �� ¦ � �� � � ¦ � � � � ¦ �<br />
Æ ¡Ø lepton (core) � ¦ � � � �� ¦ � � � � ¦ �<br />
Æ ¡Ø kaon (core) � ¦ � �� � �� ¦ � �� � � ¦ � �<br />
Æ ¡Ø NT1 (core) � �� ¦ � �� � �� ¦ � � � � ¦ � �<br />
Æ ¡Ø NT2 (core) � �� ¦ � � � �� ¦ � � � � ¦ �<br />
Æ ¡Ø notag (core) � � ¦ � �� � �� ¦ � � � ¦ � �<br />
Scale (tail) � ¦ � � ¦ � �� �� ¦ � �<br />
Æ ¡Ø (tail) �� �� ¦ ���� ���� ¦ � � ���� ¦ � �<br />
�(tail) � � ¦ � � � � ¦ � � � � ¦ � �<br />
�(outlier) � ¦ � � ¦ � � � ¦ �<br />
Table 7-10. Parameters for Ê×�� obta<strong>in</strong>ed from the Run 1 and Run 2 Breco tagged + untagged samples. The<br />
Breco MC results are shown for comparison.<br />
7.7 The maximum likelihood analysis<br />
An unb<strong>in</strong>ned maximum likelihood fit is used to simultaneously extract yields and �È asymmetry parameters<br />
from comb<strong>in</strong>ed tagged and untagged � � sample. The only new feature of the fitt<strong>in</strong>g technique relative to<br />
the branch<strong>in</strong>g fraction analysis is the addition of a PDF describ<strong>in</strong>g the time dependence <strong>in</strong> each component<br />
and tagg<strong>in</strong>g category.<br />
7.7.1 Likelihood function<br />
The overall construction of the likelihood function Ä is similar to the branch<strong>in</strong>g fraction analysis. For this<br />
analysis, the sample consists of signal and background components for the three species (��,Ã�, and ÃÃ),<br />
separated by the flavor and category of the tag side. In addiction to the usual variables Ñ�Ë, ¡�, the Fisher<br />
discrim<strong>in</strong>ant � and the � ��Ö�Ò�ÓÚ angle, the ¡Ø measurement facilitates provides additional background<br />
rejection.<br />
The probability �� for a s<strong>in</strong>gle event � <strong>in</strong> tag category is the sum of probabilities over all components,<br />
�� � ��<br />
Æ � �� È ��<br />
��<br />
ÆÃÃ<br />
Æ �ÃÃÈ ÃÃ<br />
��<br />
ÆÃ�<br />
Æ �Ã�<br />
���<br />
Æ � ��� È ���<br />
��<br />
Æ�ÃÃ<br />
Æ � �ÃÃ È �ÃÃ<br />
��<br />
�Ã� È Ã �<br />
��<br />
�� ��<br />
�<br />
Æ<br />
��Ã� È �à �<br />
��<br />
(7.10)<br />
ANALYSIS OF THE TIME-DEPENDENT �È -VIOLATING ASYMMETRY IN � � � � DECAYS