ViewVC Help
View File | Revision Log | Show Annotations | Root Listing
root/cvsroot/UserCode/claudioc/OSNote2010/triggereff.tex
(Generate patch)

Comparing UserCode/claudioc/OSNote2010/triggereff.tex (file contents):
Revision 1.3 by claudioc, Fri Nov 5 23:07:43 2010 UTC vs.
Revision 1.4 by benhoob, Mon Nov 8 11:08:41 2010 UTC

# Line 12 | Line 12 | as a function of dilepton species ($ee$,
12   of the individual leptons, and, in the case of muons, the $|\eta|$
13   of the muons.  We believe that this model is adequate for
14   the trigger efficiency precision needed for this analysis.
15 <
16 < The model assumptions are the following {\color{red} (The
17 < xx below need to be fixed using the final JSON.  For the 11 pb
18 < iteration the trigger efficiency was taken as 100\%)}
19 <
20 < \begin{itemize}
21 <
22 < \item Muon and electron trigger turn-ons as a function of $P_T$
23 < are infinitely sharp. {\color{red} Can we add references?}
24 <
25 < \item All electron triggers with no ID have 100\%
26 < efficiency for electrons passing our analysis cuts. {\color{red}
27 < Can we add a reference?  Pehaps the top documentation?}
28 <
29 < \item Electron triggers with (Tight(er))CaloEleId have 100\%
30 < efficiency with respect to our offline selection.  This we
31 < verified via tag-and-probe on $Z\to ee$.
32 <
33 < \item Electron triggers with EleId have somewhat lower
34 < efficiency.  This was also measured by tag-and-probe.
35 <
36 < \item The single muon trigger has zero efficiency for $|\eta|>2.1$.
37 < This is conservative, the trigger efficiency here is of order
38 < $\approx 40\%$.
39 <
40 < \item If a muon in $|\eta|>2.1$ fails the single muon trigger, it
41 < will also fail the double muon trigger.
42 <
43 < \item The double muon trigger has efficiency
44 < equal to the square of the single muon efficiency.
45 <
46 < \item The $e\mu$ triggers have no efficiency if the muon has $|\eta|>2.1$.
47 <
48 < \end{itemize}
49 <
50 < The model also uses some luminosity fractions and some trigger
51 < efficiencies.
52 <
53 < \begin{itemize}
54 <
55 < \item $\epsilon_{\mu}$={\color{red}xx}, the single muon trigger efficiency plateau.
56 <
57 < \item $f9$={\color{red}xx}: fraction of data with the Mu9 trigger unprescaled.  
58 < (run$\le 147116$).
59 <
60 < \item $f11$={\color{red}xx} fraction of data with the Mu9 trigger prescaled and
61 < the Mu11 trigger unprescaled.
62 < (147196 $\leq$ run $\leq$ 148058).
63 <
64 < \item $e10$={\color{red}xx}: fraction of data with the 10 GeV unprescaled electron triggers.
65 < (run$\le 139980$).
66 <
67 < \item $e15$={\color{red}xx}: fraction of data with the 15 GeV unprescaled electron triggers.
68 < (139980 $<$ run $\leq$ 144114).
69 <
70 < \item $e17$={\color{red}xx}: fraction of data with the 100\% efficient 17 GeV unprescaled electron triggers.
71 < (144114 $<$ run $\leq$ 147116).
72 <
73 < \item $e17b$={\color{red}xx}: fraction of data with 17 GeV unprescaled electron triggers
74 < with efficiency $\epsilon_e^b=90\%$ (as measured by tag-and-probe).
75 < (147116 $<$ run $\leq$ 148058).
76 <
77 < \item $emess$={\color{red}xx}: the remainder of the run with several different electron
78 < triggers, all of $P_T>17$ GeV.  For this period we measure the
79 < luminosity-weighted
80 < trigger efficiency $\epsilon(P_T)$ via tag and probe to be 99\%
81 < ($17<P_T<22$, 97\% ($22<P_T<27$), 98\% ($27<P_T<32$) and
82 < 100\% ($P_T>32$).
83 <
84 < \end{itemize}
85 <
86 < The full trigger efficiency model is described separately for
87 < $ee$, $e\mu$, and $\mu\mu$.
88 <
89 < \subsection{$ee$ efficiency model}
90 < \label{sec:eemodel}
91 <
92 < This is the easiest.  Throughout the 2010 run we have always
93 < had dielectron triggers with thresholds lower than our (20,10)
94 < analysis thresholds.  Since electron triggers are 100\% efficient,
95 < the trigger efficiency for $ee$ is 100\%.  We have verified that
96 < the efficiency of the dielectron trigger is 100\% with respect
97 < to the single electron trigger using $Z \to ee$ data.
98 <
99 < \subsection{$\mu\mu$ efficiency model}
100 < \label{sec:mmmodel}
101 <
102 < We consider different cases.
103 <
104 < \subsubsection{Both muons in $|\eta|<2.1$ and with $P_T>15$ GeV}
105 < This is the bulk of the $\mu\mu$.
106 <
107 < \begin{center}
108 < $\epsilon = 1 - (1-\epsilon_{\mu})^2$
109 < \end{center}
110 <
111 < \subsubsection{Both muons in $|\eta|<2.1$, one muon with $11<P_T<15$ GeV}
112 < In this case there must be a muon with $P_T>20$ GeV.  The single muon
113 < trigger is operative for the full dataset on this muon.  Some loss
114 < of efficiency can be recovered when the 2nd muon fires the trigger.
115 < But this can happen only for a fraction of the run.  The dimuon trigger
116 < cannot fire in our model to recover any of the efficiency lost by
117 < the single muon trigger on the high $P_T$ muon.
118 <
119 < \begin{center}
120 < $\epsilon = \epsilon_{\mu} + (1-\epsilon_{\mu})\epsilon_{\mu}(f9+f11)$
121 < \end{center}
122 <
123 < \subsubsection{Both muons in $|\eta|<2.1$, one muon with $10<P_T<11$ GeV}
124 < Same basic idea as above.
125 <
126 < \begin{center}
127 < $\epsilon = \epsilon_{\mu} + (1-\epsilon_{\mu})\epsilon_{\mu}f9$
128 < \end{center}
129 <
130 < \subsubsection{Both muons with $|\eta|>2.1$}
131 < This is a very small fraction of events.  In our model they can only be
132 < triggered by the dimuon trigger.
133 <
134 < \begin{center}
135 < $\epsilon = \epsilon_{\mu}^2$
136 < \end{center}
137 <
138 < \subsubsection{First muon with $P_T>15$ and $|\eta|<2.1$;  second muon
139 < with $|\eta|>2.1$}
140 < The single muon trigger is always operative.  If it fails the double muon
141 < trigger also fails.
142 <
143 < \begin{center}
144 < $\epsilon = \epsilon_{\mu}$
145 < \end{center}
146 <
147 < \subsubsection{First muon with $11<P_T<15$ and $|\eta|<2.1$;  second muon
148 < with $|\eta|>2.1$}
149 < The single muon trigger is operative only for a fraction of the run.
150 < For the remaining fraction, we must rely on the double muon trigger.
151 <
152 < \begin{center}
153 < $\epsilon = (f9+f11)\epsilon_{\mu} + (1-f9-f11)\epsilon_{\mu}^2$
154 < \end{center}
155 <
156 < \subsubsection{First muon with $10<P_T<11$ and $|\eta|<2.1$;  second muon
157 < with $|\eta|>2.1$}
158 < Same basic idea as above.
159 <
160 < \begin{center}
161 < $\epsilon = f9~\epsilon_{\mu} + (1-f9)\epsilon_{\mu}^2$
162 < \end{center}
163 <
164 < \subsection{$e\mu$ efficiency model}
165 < \label{sec:emumodel}
166 <
167 < This is the most complicated case.  The idea is that the muon trigger
168 < is used to get the bulk of the efficiency.  Then the single electron
169 < trigger(s) and the $e\mu$ triggers are used to get back dome of the
170 < efficiency loss.  The various cases are listed below.
171 <
172 < \subsubsection{Muon with $|\eta|<2.1$ and $P_T>15$}
173 < This is the bulk of the acceptance.
174 <
175 < \begin{center}
176 < $\epsilon = \epsilon_{\mu} + (1-\epsilon_{\mu})\Delta_1$
177 < \end{center}
178 <
179 < where $\Delta_1$ is the efficiency from the electron trigger:
180 < \begin{itemize}
181 < \item $P_T(ele)<15 \to \Delta_1=e10$
182 < \item $15<P_T(ele)<17 \to \Delta_1=e10+e15$
183 < \item $P_T(ele)>15 \to \Delta_1=e10+e15+e17+\epsilon_e^b~e17b+\epsilon(P_T)~emess$
184 < \end{itemize}
185 <
186 <
187 < \subsubsection{Muon with $|\eta|<2.1$ and $11<P_T>15$}
188 <
189 < This is the similar to the previous case, except that the muon
190 < trigger is operative only for a subset of the data taking period.
191 <
192 < \begin{center}
193 < $\epsilon = (f11+f9)\epsilon_{\mu} + \Delta_2 + \Delta_3$
194 < \end{center}
195 <
196 < Here $\Delta_2$ is associated with the period where the muon
197 < trigger was at 15 GeV, in which case we use electron triggers or
198 < $e\mu$ triggers.  Note that the electron in this case must be
199 < above 20 GeV.  This can happen only in the latter part of the run,
200 < thus we write
201 < \begin{center}
202 < $\Delta_2 = (1-f11-f9)~(\epsilon_{\mu}~+~
203 < (1-\epsilon_{\mu})\epsilon(P_T))$
204 < \end{center}
205 < \noindent where the first term is for the $e\mu$ trigger and the
206 < second term corresponds to $e\mu$ trigger failures, in which case we have
207 < to rely on the electron trigger.
208 <
209 < Then, $\Delta_3$ is associated with muon trigger failures in early runs,
210 < {\em i.e.}, run $<148819$.  In this case the electron trigger picks it
211 < up and the $e\mu$ trigger does not help.  
212 <
213 < \begin{center}
214 < $\Delta_3 = (f11+f9)(1-\epsilon_{\mu}) \cdot \epsilon_e$
215 < \end{center}
216 <
217 < \noindent where $\epsilon_e$ is the efficiency of the electron
218 < trigger for $P_T>20$.  This is 100\% up to run 147716 (fraction
219 < $(e10_e15+e17)/(f11+f9)$;  then it is somewhat lower up to
220 < run 148058, then it becomes very close to 100\% again.
221 < For this latter part of the run we approximate it as $\epsilon_e^b$.
222 < Thus:
223 <
224 < \begin{center}
225 < $\epsilon_e = (e10_e15+e17)/(f11+f9) +
226 < \epsilon_e^b(f11+f9-e10-e15-e17)/(f11+f9)$
227 < \end{center}
228 <
229 < \subsubsection{Muon with $|\eta|<2.1$ and $9<P_T>11$}
230 <
231 < Identical to the previous case, but replace $(f11+f9)$ with $f9$ everywhere.
232 <
233 < \subsubsection{Muon with $|\eta|>2.1$}
234 <
235 < This is a 10\% effect to start with.  We assume no single muon efficiency,
236 < no $e\mu$ efficiency.  Then we can only ise the single electron trigger.
237 <
238 < \begin{center}
239 < $\epsilon = \Delta_1$
240 < \end{center}
241 <
242 < \subsection{Summary of the trigger efficiency model}
243 < \label{sec:trgeffsum}
15 > Details are given in App.~\ref{sec:appendix_trigger}.
16  
17   We take the trigger efficiency for $ee$ as 100\%.  The trigger efficiency
18   for the $e\mu$ and $\mu\mu$ final states is summarized in Figures xx.

Diff Legend

Removed lines
+ Added lines
< Changed lines
> Changed lines