forked from alisw/AliRoot
-
Notifications
You must be signed in to change notification settings - Fork 0
/
Copy pathREADME
353 lines (262 loc) · 12.2 KB
/
README
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
README file for ALICE Time Of Flight Detector Offline Code
==========================================================
Intorduction
------------
This is a short overview of the TOF code within the AliROOT framework.
Some additional details have been introduced to
Structure
---------
There are 3 libraries build for the TOF. These are
* libTOFbase:
This contains the basic stuff, like data classes and managers.
* libTOFsim:
This contains code used by the simulation only. This includes the
detector class, AliTOF, and its derivatives. It also contains the
code for building the geometry, as well as the (s)digitisers, raw
data writer, QA checker and data containers.
* libTOFrec:
Code needed for the reconstruction. This includes the reconstruction
code itself, as well as cluster and track containers and QA checker.
The content of these libraries is detailed more below.
libTOFbase:
-----------
Till today (February 6th 2008), it contains the following classes
AliTOFGeometry:
Manager of TOF geometry data. All code queries this manager
for geometry parameters, so that the data are always consistent.
AliTOFdigit
AliTOFrawData
AliTOFHitData
AliTOFHitDataBuffer
Base classes for digits and real digits. They are all data
classes that hold the TOT and TOF values for a single sensitive
TOF element.
AliTOFChannelOffline
AliTOFChannelOnline
AliTOFChannelOnlineStatus
AliTOFcalib
AliTOFDataDCS
AliTOFFormatDCS:
Calibration data classes.
AliTOFRawMap:
A map of (AliTOFrawData) indices.
The AliTOFRawStream class uses this map to store raw data
before making digits or clusters.
AliTOFDecoder
AliTOFRawStream:
Classes to read raw data files.
AliTOFAlignment:
AliTOFPreprocessor
AliTOFPreprocessorFDR:
libTOFsim:
----------
Till today (February 6th 2008), it contains the following classes
AliTOF:
Manager for all TOF simulation code.
AliTOFv5T0
AliTOFv6T0:
Simulation drivers for the TOF detector.
AliTOFv5T0 corresponds to a simulation where services are not
completly described
AliTOFv6T0 contains a more detailed description of all TOF
detector components.
AliTOFhit
AliTOFhitT0:
Base classes for hits. They hold the geometrical and physical
informations of a single sensitive TOF element, like the ALICE
coordinates, the detector indices, i.e. 5 integer numbers
(sector, module, strip, par-row and pad numbers), the hit
coordinates in the pad reference system and the
time-of-flight measurement. Moreover, they hold also some
additional measurements, like the momentum components, the
energy loss in the sensitive TOF element and the track incident
angle on the pad. Only the AliTOFhitT0 object contains also
the track length measurement.
AliTOFSDigit:
Base classes for sdigits. They hold the TOF detector informations,
like the detector indices, i.e. 5 integer numbers
(sector, module, strip, par-row and pad numbers), the
time-of-flight and the time-over-threshold informations
according to the test beam results.
Each detector element can record more than one sdigit (but
not more than 3).
AliTOFSDigitizer
AliTOFDigitizer:
Base class for the (s)digitiser. AliTOFSDigitizer makes
summable digits (AliTOFSDigit) from hits, and AliTOFDigitizer
makes digits (quasi real data) from summable digits.
AliTOFHitMap
A map of (AliTOFSDigit) indices.
The AliTOFSDigitizer uses this map to store simulation data
(i.e. hits) before making sdigits.
AliTOFDigitMap:
A map of (AliTOFdigit) indices.
The AliDDLRawData uses this map to store the TOF digits indices
before making real digits (i.e. raw data).
AliTOFDDLRawData:
Base class for digit-to-raw_data transformation.
It makes raw data from digits: practically, it transforms the
5 detector indices (sector, module, strip, pad-row and pad numbers)
in hardware address, consisting of 5 induces (TOF readout
module, slot, chain, TDC and channel numbers).
AliTOFT0:
AliTOFTrigger:
AliTOFQAChecker
AliTOFQADataMakerSim
libTOFrec:
----------
Till today (February 6th 2008), it contains the following classes
AliTOFRecoParam:
AliTOFReconstructor:
AliTOFcluster:
Reconstructed point in the TOF. These objects are made
AliTOFReconstructor.
AliTOFClusterFinder:
AliTOFtrack:
Base classe for TOF tracks. It holds ...
AliTOFtracker
AliTOFtrackerMI
AliTOFtrackerV1:
AliTOFpidESD:
AliTOFQADataMakerRec:
TOF Calibration:
----------------
1. Online Calibration
1.1. New Calibration Schema
1.1.1. Configuration
The online calibration which is performed by the TOF preprocessor is
configured according to a CDB object (stored in /TOF/Calib/Config), where
a flag for the computation of the delays is set according to the type
of data taking (cosmics ---> kFALSE / beam ---> kTRUE), and where the
starting validity of the calibration objects that will be written in the
OCDB is defined (see sec. 1.1.3.). The data are stored in the CDB object
as entries in a TMap, with IDs "ComputingDelays" and "StartingRun"
respectively.
1.1.2. Objects
- AliTOFChannelOnlineArray: array of floats containing the delay value
calculated for each TOF channel by the TOF preprocessor starting from
the DAQ DA for PHYSICS runs (see TOFda.cxx). Inheriting from TObject.
- AliTOFChannelOnlineStatusArray: array of chars defining the status for each
TOF channel according to the processing of the data coming from PULSER and
NOISE runs (TOFpulserda.cxx, TOFnoiseda.cxx). The status is defined also
according to the FEE map written in the DCS FXS, where the status ON/OFF
of the channels is stored. The first (least significant) two bits refer to the
FEE status, the second two to the pulser data, and the third two to the noise
data, leaving the last two empy. The status is always (FEE/pulser/noise)
defined as:
00 --> Unknown;
01 --> Good;
10 --> Bad.
Inheriting from TObject.
1.1.3. OCDB
- /TOF/Calib/ParOnlineDelay: directory where the AliTOFChannelOnlineArray
calibration objects are stored, with validity [0, 999999999], increasing the
sv number every time. After offline calibration takes place, in case a reset
is needed at run XYZ, the validity changes to [XYZ, 999999999], again
with increasing sv.
- /TOF/Calib/Status: directory where the AliTOFChannelOnlineStatusArray
calibration objects are stored, with validity [current_run, 999999999]. In
case of a PHYSICS run, the update occurs only if the FEE map has changed.
In case of a PULSER/NOISE run, the update occurs once at the very end of the
processing, so to merge the information from the FEE status map and those
from the TOFpulserda/TOFnoiseda.
1.1.4. Reference Data
- /TOF/Calib/DAQData: directory to store the histograms at run level that
are produced by the TOFda.
- /TOF/Calib/DCSData: directory to store the data that come out from the
processing of the TOF DCS DPs.
- /TOF/Calib/PulserData: directory to store the histograms that are produced
by the TOFpulserda.
- /TOF/Calib/NoiseData: directory to store the histograms that are produced
by the TOFnoiseda.
- /TOF/Calib/FEEData: directory to store the histogram reproducing the FEE
status of the TOF channels.
1.1.5. Usage in Reconstruction
During reconstruction, both the AliTOFChannelOnlineArray and the
AliTOFChannelOnlineStatusArray corresponding to the current run have to be
loaded from OCDB in the AliTOFReconstructor class instance. From there,
they are passed to the AliTOFClusterFinder, where the status of the channel is
used in order to decide whether to use it or not, while the delay is used to
calibrate when the offline calibration information is not yet available.
1.2. Old Calibration Schema
1.2.1. Configuration
No OCDB configuration entry is foreseen.
1.2.2. Objects
- AliTOFChannelOnline: object containing the value of the delay for a
certain TOF channel. Inheriting from TObject. An TObjArray of 157248 of such
objects is used to store the information coming from the TOF online
calibration. Inheriting from TObject.
- AliTOFChannelOnlineStatus: object containing the status of a TOF channel
as determined during the reading of the FEE map/ during a pulser run/
during a noise run. Three TObjArray objects of 157248 of such objects should
be present in the OCDB for each run: one related to the FEE status of the
channels, one related to pulser run results, and one related to noise
run results. The status is defined as:
00 --> Unknown;
01 --> Good;
10 --> Bad.
Inheriting from TObject.
1.2.3. OCDB
- /TOF/Calib/ParOnline: directory where a TObjArray of 157248 AliTOFChannelOnline
calibration objects are stored, with validity [0, 999999999], increasing the
sv number every time. After offline calibration takes place, in case a reset
is needed at run XYZ, the validity changes to [XYZ, 999999999], again
with increasing sv.
- /TOF/Calib/HW: directory where a TObjArray of 157248 AliTOFChannelOnlineStatus
calibration objects are stored, with validity [current_run, 999999999], as
obtained from reading the FEE map from the DCS FXS. The update occurs only if
the FEE map has changed.
- /TOF/Calib/Pulser: directory where a TObjArray of 157248 AliTOFChannelOnlineStatus
calibration objects are stored, with validity [current_run, 999999999], as
obtained from a pulser run.
- /TOF/Calib/Noise: directory where a TObjArray of 157248 AliTOFChannelOnlineStatus
calibration objects are stored, with validity [current_run, 999999999], as
obtained from a noise run.
1.2.4. Reference Data
- /TOF/Calib/DAQData: directory to store the histograms at run level that
are produced by the TOFda.
- /TOF/Calib/DCSData: directory to store the data that come out from the
processing of the TOF DCS DPs.
- /TOF/Calib/PulserData: directory to store the histograms that are produced
by the TOFpulserda.
- /TOF/Calib/NoiseData: directory to store the histograms that are produced
by the TOFnoiseda.
- /TOF/Calib/FEEData: directory to store the histogram reproducing the FEE
status of the TOF channels.
1.2.5. Usage in Reconstruction
During reconstruction, the TObjArray of AliTOFChannelOnline and the three
TObjArray objects of AliTOFChannelOnlineStatus coming from the FEE map, the
pulser run data, and the noise run data corresponding to the current run have to
be loaded from OCDB in the AliTOFReconstructor class instance. From there,
they are passed to the AliTOFClusterFinder, where the status of the channel is
used in order to decide whether to use it or not, while the delay is used to
calibrate when the offline calibration information is not yet available.
2. TOF Offline Calibration
2.1. Object
- AliTOFChannelOffline: object containing the calibration parameters for
each TOF channel that should correct both for the delay introduced by the
electronics and the hardware, and for the time slewing effect. A TObjArray
of 157248 of such objects is stored in the CDB to perform refined calibration
during reconstruction. Inheriting from TObject.
2.2. OCDB
- /TOF/Calib/ParOffline: directory containing the CDB entry corresponding to the
offline calibration of the TOF as stored in a TObjArray object of 157248
AliTOFChannelOffline objects with validity [0, 999999999], increasing the
sv number every time. In case a reset is needed at run XYZ, after collecting
the statistics necessary to the offline calibration (when the online
calibration object becomes valid again), the validity changes to
[XYZ, 999999999], again with increasing sv.
2.3 Usage in Reconstruction
The TObjArray of 157248 AliTOFChannelOffline objects is retrieved for the current
run in AliTOFReconstructor, and passed to AliTOFClusterFinder. As soon as enough
statistics is collected for every channel, since the validity
of the offline calibration object was set, for each channel with a valid
status, the calibration is performed using the calibration parameters present in
this TObjArray of AliTOFChannelOffline.
Authors:
--------
Annalisa De Caro <decaro@sa.infn.it>
----------------------------------------------------------------------
Local Variables:
mode: text
End: