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Okay, thank you. And I'll present your
results on the soft QC and exclusive

2
00:00:07,139 --> 00:00:14,609
processes with nhB. I'll first discuss our
results on both ice 10 correlations in

3
00:00:14,609 --> 00:00:18,779
proton proton collisions. Then I'll go
over to the measurement of the inelastic

4
00:00:18,779 --> 00:00:23,549
proton proton cross section. And finally,
I'll show you results on central x with

5
00:00:23,549 --> 00:00:30,539
production objects I input on proton and
in left conditions. So, first going over

6
00:00:30,539 --> 00:00:36,179
to the Bose Einstein correlations. If we
have an incoherent source of identical

7
00:00:36,509 --> 00:00:40,679
bosons, then of course, our system needs
to be symmetric on the exchange of the

8
00:00:40,679 --> 00:00:46,259
identical bosoms. And what happens then is
that different parts of the symmetrized

9
00:00:46,649 --> 00:00:52,199
wave function will interfere
constructively and this gives rise to the

10
00:00:52,229 --> 00:00:57,659
Bose Einstein correlation effect. Now to
understand a bit better, let's consider

11
00:00:57,809 --> 00:01:05,219
two point sources of items. COBOL zones,
let's take same time patterns, then the

12
00:01:05,219 --> 00:01:10,259
two pi n wave function has can be
described by the fact that you have

13
00:01:10,259 --> 00:01:16,889
pythons emitted from source alpha detected
in detector a with momentum K and pi and

14
00:01:16,919 --> 00:01:21,869
emitted from source beta detected in
detector view with momentum kb. And then

15
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of course, you also have the interchange
situations where payments are emitted from

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00:01:26,819 --> 00:01:31,529
source alpha and detected in detector B,
and fines are emitted from source beta

17
00:01:31,529 --> 00:01:37,289
detected in detector a. Now, if we assume
that we can describe everything by plane

18
00:01:37,289 --> 00:01:42,899
waves, then the amplitude squared of our
two pi n system has the form one plus

19
00:01:42,899 --> 00:01:48,389
cosine delta k times delta r where delta k
is the difference in momentum between the

20
00:01:48,389 --> 00:01:55,259
two piles and delta r is the distance
between the sources. So, our to pine

21
00:01:55,259 --> 00:01:59,969
correlation function will be proportional
to one plus cosine delta k times delta r

22
00:02:00,509 --> 00:02:05,639
And this illustrate that the Bose Einstein
correlation effect actually measures the

23
00:02:05,639 --> 00:02:11,729
projection of the distance between the two
sources on to the difference between the

24
00:02:11,729 --> 00:02:18,119
momenta of the particles. Now, this
principle has already been applied in 56

25
00:02:18,149 --> 00:02:23,489
by Henry brown and twist for the
measurement of stellar radii. in particle

26
00:02:23,489 --> 00:02:27,479
physics, it has been observed for the
first time important antiproton collisions

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00:02:27,479 --> 00:02:34,379
in 59 already has been seen at Elysee in
PPP lead and lead collisions. And it has

28
00:02:34,379 --> 00:02:38,579
also been observed in equals A minus
emulation and there are some measurements

29
00:02:38,579 --> 00:02:44,609
in deep inelastic scattering. Now, we can
generalize this situation of having to

30
00:02:44,609 --> 00:02:50,579
point sources to a continuous space time
distribution of sources. And there the two

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00:02:50,579 --> 00:02:56,279
kind of two particle correlation function
is usually parametrized of the form one

32
00:02:56,279 --> 00:03:02,819
plus lambda times the exponential of minus
R times T U where r is the measure for the

33
00:03:02,819 --> 00:03:07,949
size of our source you can think of it as
the radius in case of a strictly symmetric

34
00:03:07,949 --> 00:03:12,779
system, Q is a Lorentz invariant, which is
a measure for the difference in for

35
00:03:12,779 --> 00:03:18,389
momentum between the two particles and
love that is the capacity and it is zero

36
00:03:18,389 --> 00:03:23,849
in case of completely coherent sources
when we don't have any Bose Einstein

37
00:03:23,849 --> 00:03:30,779
correlation and love days one in case of
completely incoherent sources. Now,

38
00:03:30,779 --> 00:03:38,639
usually, in data, we extract the two
particle correlation function by

39
00:03:38,849 --> 00:03:44,279
constructing the ratio of the distribution
of two pylons containing the Bose Einstein

40
00:03:44,579 --> 00:03:51,839
correlation effect to a reference sample,
which doesn't contain the Bose Einstein

41
00:03:51,839 --> 00:03:56,549
correlation effect. And one way of
constructing this reference sample is by

42
00:03:57,089 --> 00:04:03,779
combining two pints from different events.
Now, there was a there was always some

43
00:04:03,779 --> 00:04:08,669
imperfections related to this construction
of this reference sample and to cancel out

44
00:04:08,669 --> 00:04:14,159
these imperfections, what I usually
extract is the double ratio of the two

45
00:04:14,159 --> 00:04:18,719
particle correlation function from data
which contains possession correlation

46
00:04:18,719 --> 00:04:23,309
effects, and the top part of the
correlation function from simulation which

47
00:04:23,309 --> 00:04:25,379
is free from the Bose Einstein
correlation.

48
00:04:27,720 --> 00:04:33,690
Now, we looked at this Bose Einstein
correlation as LGB important proton

49
00:04:33,690 --> 00:04:38,430
collisions at the center of mass energy of
70 v we selected same time payments we

50
00:04:38,430 --> 00:04:42,960
transact momentum above hundred annually
and through the rapid team between two and

51
00:04:42,960 --> 00:04:47,460
five. We analyzed the bull's eye 10
correlation effect as a function of

52
00:04:47,520 --> 00:04:53,190
charged particle multiplicity. Now, if you
want to compare two results from other

53
00:04:53,190 --> 00:04:56,700
experiments, of course, particle
ellipticity is not a very practical

54
00:04:56,700 --> 00:05:02,310
quantity. So, instead one construct so
called accurate tivity classes, where the

55
00:05:02,310 --> 00:05:09,720
low activity class corresponds to 48% of
the event or primary tissues with lowest

56
00:05:09,720 --> 00:05:15,780
multiplicity. Now, we have the medium
activity class which corresponds to 37% of

57
00:05:16,320 --> 00:05:20,280
primary vertices with higher multiplicity
and then we have the high activity class

58
00:05:20,280 --> 00:05:26,580
which corresponds to 15% of the primary
dishes with highest multiplicity. Now,

59
00:05:26,580 --> 00:05:32,580
here you see this double ratio of data to
MonteCarlo as a function of q, which is a

60
00:05:32,580 --> 00:05:37,170
measure for difference in for momentum of
the two piles. And you see from top to

61
00:05:37,170 --> 00:05:42,660
bottom for low medium and high activity
classes. And what you see is that this

62
00:05:42,660 --> 00:05:49,980
double ratio increases at low values of Q
and this is a manifestation of the Bose

63
00:05:49,980 --> 00:05:55,620
Einstein correlations. Now, we fit the
deserve red data points with the

64
00:05:55,620 --> 00:06:00,480
parameterization I described before and
you extracted the parameters are Which is

65
00:06:00,480 --> 00:06:05,580
a measure for the size of your source and
love that the county city as a function of

66
00:06:05,580 --> 00:06:10,620
the activity classes, and here you see on
the right sorry on the left are and you

67
00:06:10,620 --> 00:06:15,720
see that it increases with increasing
particle multiplicity and on the other

68
00:06:15,720 --> 00:06:21,390
hand love that decreases with increasing
particle multiplicity. Now, the same trend

69
00:06:21,390 --> 00:06:25,860
has also been observed in other
experiments. And in particular, we can

70
00:06:25,860 --> 00:06:32,700
next compare our values for R and lambda
with those obtained from Atlas at 70 v.

71
00:06:32,880 --> 00:06:38,220
And in general, the values for R and
lambda from A to B are a bit lower than

72
00:06:38,220 --> 00:06:44,490
those from Atlas. And now over to the
internet st cross section which is of

73
00:06:44,490 --> 00:06:49,560
course, a fundamental quantity in hedonic
interactions, but it's also of importance

74
00:06:49,560 --> 00:06:53,820
for for example, as to particle physics
because it enters the description of the

75
00:06:53,820 --> 00:06:58,230
air showers from cosmic rays, and the
description of the transport of cosmic ray

76
00:06:58,230 --> 00:07:03,060
particles in the interstellar medium. Now
we extracted the inelastic cross section

77
00:07:03,060 --> 00:07:08,430
at LGB important proton collisions at
center of mass energy of 13. tv and also

78
00:07:08,430 --> 00:07:13,890
seven TV. And we used an unbiased sample
of proton proton collisions. And we only

79
00:07:13,890 --> 00:07:19,830
analyzed the data of the leading bunch in
each run in order to avoid background from

80
00:07:19,830 --> 00:07:26,220
pileup, and in total, we collected a
luminosity of 10.7 inverse nanobots.

81
00:07:27,750 --> 00:07:32,340
First, we extracted the fiducial inelastic
cross section for the cross section in the

82
00:07:32,340 --> 00:07:38,070
acceptance, and we constructed it by
looking at the number of events or proton

83
00:07:38,070 --> 00:07:43,200
proton collisions containing at least one
front lift a charged particle with

84
00:07:43,200 --> 00:07:48,930
momentum above two GVM. pseudo rapidity
between two and five. We, of course,

85
00:07:48,930 --> 00:07:54,870
divided our number of events by our total
luminosity, and we multiply it by you,

86
00:07:54,900 --> 00:07:59,460
which is our average number of
interactions per event and we corrected

87
00:07:59,820 --> 00:08:06,420
for Background by looking at a bunch of
square one of the beams was empty. So, we

88
00:08:06,420 --> 00:08:11,520
obtained a fiducial inelastic cross
section of 62.2 million barns with a

89
00:08:11,520 --> 00:08:15,960
systematic uncertainty of Oh point two and
a systematic diversity coming from the

90
00:08:15,960 --> 00:08:22,980
luminosity measurement of 2.5 our
statistical uncertainties neglige then we

91
00:08:22,980 --> 00:08:29,400
extrapolated our fiducial inelastic cross
section to obtain the total inelastic

92
00:08:29,400 --> 00:08:34,140
cross section and we took into account the
fractional contribution to the inelastic

93
00:08:34,140 --> 00:08:38,880
cross section of non defective single
diffractive and double diffractive

94
00:08:39,240 --> 00:08:45,000
processes, we neglected the interference
between these two these three types of

95
00:08:45,540 --> 00:08:49,560
processes and we also neglected the
contribution from Central exclusive

96
00:08:49,560 --> 00:08:57,180
production. And then we had to multiply a
fractional contribution FX by the fraction

97
00:08:57,180 --> 00:09:02,340
of interactions inside our acceptance for
Each of our sub processes and this number

98
00:09:02,340 --> 00:09:04,290
was obtained from a syringe.

99
00:09:05,970 --> 00:09:13,590
I obtained a total inelastic cross section
of 75.4 million barn with three Mewbourne

100
00:09:13,590 --> 00:09:19,560
uncertainty coming from the experiment and
4.5 coming from the extrapolation. And

101
00:09:19,560 --> 00:09:22,980
here you see the total inelastic cross
section as a function of the center of

102
00:09:22,980 --> 00:09:30,510
mass energy, where the red points are the
results from nhB x seven and 13. tv and

103
00:09:30,510 --> 00:09:35,820
you see that our results are in good
agreement with Atlas and total. Now, go

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00:09:35,820 --> 00:09:40,920
over to the exclusive chip side production
in ultra peripheral collisions. So, in

105
00:09:40,950 --> 00:09:45,750
ultra peripheral collisions, the beam
particles interact at a distance far from

106
00:09:45,750 --> 00:09:50,370
one another. And for the exclusive
production of jPi. One of the being

107
00:09:50,370 --> 00:09:55,860
particles emits a real photon this photon
splits into a Quark anti quarter. This

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00:09:55,860 --> 00:10:00,840
work ethic worker interacts with the other
being particle to the exchange of to glue

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00:10:00,840 --> 00:10:06,720
on, and finally the to the park and
antique Park combined into Jake sire.

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00:10:06,900 --> 00:10:13,290
Another problem. And it's interesting to
look at these exclusive processes, among

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00:10:13,320 --> 00:10:17,700
others because they give access to quote
to so called generalized partisan

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00:10:17,700 --> 00:10:23,970
distributions, which are a generalization
of the standard PDF. And those generalize

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00:10:23,970 --> 00:10:29,400
parts and distributions give access to the
distribution of partners not only as a

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00:10:29,400 --> 00:10:33,810
function of their longitudinal momentum
fraction x, but also as a function of

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00:10:33,810 --> 00:10:39,480
their transverse position. Now, let's see
where it's high energy. So in other words,

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00:10:39,480 --> 00:10:44,760
we can reach very low values of exposure.
And at these very low values of x, we can

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00:10:44,760 --> 00:10:52,170
we can approximate the exclusive forces in
terms of standard blue on PDF. So by

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00:10:52,170 --> 00:10:57,390
measuring these exclusive processes, we
get access to these standards on PDF and

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00:10:57,390 --> 00:11:04,890
in addition, the high energy As he puts
us, potentially in a region where we could

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00:11:04,890 --> 00:11:13,050
probe saturation, so the recombination of
clothes, neither LGB. Usually when we look

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00:11:13,050 --> 00:11:18,510
at exclusive chipset production, the jPi
is typically reconstructed. So it's DK

122
00:11:18,510 --> 00:11:25,860
into two oppositely charged neurons which
are detected in our LCD detector. And

123
00:11:25,860 --> 00:11:29,310
since we are looking at exclusive
processes, we of course don't want to

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00:11:29,310 --> 00:11:34,680
present of any other particles than the
two neurons. So ideally, you want to see

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00:11:34,680 --> 00:11:40,590
large rapidity gaps up to close to the
beam line, void of any detector activity.

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00:11:41,580 --> 00:11:47,700
And the LGB detector itself covers a
region in solar activity between two and

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00:11:47,700 --> 00:11:54,570
five. And our villo tracker provides an
additional coverage into the rapidity

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00:11:54,570 --> 00:12:02,940
between minus 1.5 and minus 3.5. Now this
was a situation for one Run one forum to

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00:12:04,050 --> 00:12:09,990
we install the series of simulators of 200
meters away from the interaction point.

130
00:12:10,260 --> 00:12:15,600
And these simulators allowed us to extend
our coverage in rapidity between minus 10

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00:12:15,600 --> 00:12:21,090
and minus five, and between five and 10.
It was really nice to have these detectors

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00:12:21,090 --> 00:12:29,820
because it allowed us to reduce our
systematic uncertainty by 50%. So, coming

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00:12:29,820 --> 00:12:33,810
to the measurement of exclusive chip site
and I will also show you results website

134
00:12:33,810 --> 00:12:39,420
to us. So we looked among others that
proton proton collisions at 13 TV, were

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00:12:39,420 --> 00:12:44,970
both objects I am obsessed with a
reconstructed 3d case into neurons are the

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00:12:44,970 --> 00:12:51,360
nodes of up to the rapidity between two
and 4.5. As I already said, We veto any

137
00:12:51,360 --> 00:12:56,820
event where we see additional detector
activity, and furthermore, we are required

138
00:12:56,820 --> 00:13:02,760
the value on cancerous momentum squared to
be below point at V squared in order to

139
00:13:02,910 --> 00:13:08,790
reduce background in particular coming
from proton dissociation. Here you see the

140
00:13:08,790 --> 00:13:14,370
Daniel invariant mass and you clearly see
the Jake psi and the smaller site will

141
00:13:14,370 --> 00:13:19,320
speak on top of the continuous Danyoung
background that will of course the truck.

142
00:13:20,640 --> 00:13:25,500
You see the cross section differential in
rapidity on the left project side on the

143
00:13:25,500 --> 00:13:30,120
right from site to F. And on top of our
data points, you see a critical

144
00:13:30,150 --> 00:13:36,420
calculations based on the gloom standard
PDFs, you see the calculations at leading

145
00:13:36,420 --> 00:13:42,900
ordering yellow and next to leading order
in Yes, we mean it. Okay, and you see that

146
00:13:42,900 --> 00:13:46,500
the next leading order predictions
describe for data Well,

147
00:13:47,820 --> 00:13:53,580
now from the job site site twist proton
proton cross section, we can extract the

148
00:13:53,940 --> 00:13:58,710
jPi your site twist photo production cross
section, you see the foot production cross

149
00:13:58,710 --> 00:14:03,390
section on the left 48 psi and on the
right first sight to us as a function of

150
00:14:03,390 --> 00:14:08,580
the photon photon invariant maps, and
there should be measurements at 13 TV are

151
00:14:08,580 --> 00:14:15,450
given by the red data points and we see
that you see that the rich photon proton

152
00:14:15,450 --> 00:14:21,300
environment mass up to two TV. On top of
all the data points from all the

153
00:14:21,300 --> 00:14:26,310
experiments you see also again these
theoretical predictions based on standard

154
00:14:26,340 --> 00:14:31,710
un PDF next to leading order given by this
dotted line and you see that they describe

155
00:14:31,710 --> 00:14:36,720
the data well. On the other hand, a portal
of fit given by the blue curve has

156
00:14:36,720 --> 00:14:40,950
problems to describe the data points at yo
and high values of the photon photon

157
00:14:41,010 --> 00:14:48,150
invariant maps. Now, I have a last slide
showing you results on exclusive coherent

158
00:14:48,150 --> 00:14:54,810
chips I production in dead lead collisions
which gives us access to nuclear PDS or

159
00:14:54,810 --> 00:14:59,760
nuclear generalized part on distributions
and potentially also allows us to probe

160
00:15:00,000 --> 00:15:06,450
saturation. So here you see the cross
section differential in rapidity. And on

161
00:15:06,450 --> 00:15:11,790
top of our data points, you'll see a whole
series of predictions that are either

162
00:15:11,790 --> 00:15:18,600
based on nuclear standard PDF, or on the
saturation models. And I'd like to

163
00:15:18,600 --> 00:15:23,640
highlight the model from Auntie Sally at
all, which is given by the purple line and

164
00:15:23,640 --> 00:15:28,470
the magenta line, it's based on the
saturation model. And in the case of the

165
00:15:28,470 --> 00:15:35,040
purple line, they assume that the
distribution is uniform in transverse

166
00:15:35,040 --> 00:15:40,440
positioning see that this doesn't describe
our data. On the other hand, as given by

167
00:15:40,440 --> 00:15:45,900
the magenta line, if you take into account
the fluctuations of the blue and

168
00:15:45,900 --> 00:15:50,880
distributions as a function of transverse
position, you see that the model allows

169
00:15:51,150 --> 00:15:58,440
managers to describe our data well. So in
summary, I've shown you that we have clear

170
00:15:58,440 --> 00:16:02,850
signals of Bose Einstein correlations
where our results are in agreements with

171
00:16:03,480 --> 00:16:09,120
the other experiments also are in elastic
proton proton cross section, extracted

172
00:16:09,150 --> 00:16:13,920
HCBS in agreement with the other energy
experiments. And then action your results

173
00:16:13,920 --> 00:16:18,300
on exclusive cheap sigh production
important proton collisions, which are

174
00:16:18,300 --> 00:16:23,880
well described by next to leading order
standard new on PDF. And then finally,

175
00:16:23,880 --> 00:16:29,190
I've shown you results on coherent
exclusive production of jPi in lead, lead.

176
00:16:29,520 --> 00:16:36,930
And here Well, a whole series of models
based on saturation and nuclear PDS allows

177
00:16:36,960 --> 00:16:40,650
us proper data. Well so far. Thank you.

178
00:16:42,720 --> 00:16:49,320
Okay, thank you, john, for this very clear
token for the perfectly on time to the

179
00:16:49,320 --> 00:16:54,150
second. So is there any question

180
00:17:04,710 --> 00:17:12,870
And in the meantime, maybe I have one
myself. If you allow me in SQL yahzee,

181
00:17:12,870 --> 00:17:21,300
things like 10, you have listed a number
of processes, which you evaluate which one

182
00:17:21,300 --> 00:17:27,630
of those gives you most of the systematic
error when then you make the final

183
00:17:29,160 --> 00:17:30,060
calculation.

184
00:17:30,540 --> 00:17:33,270
I don't know by heart, sorry. Okay, fine.

185
00:17:52,380 --> 00:17:58,470
Okay, if no one raised his hand, I would
switch to the second presentation.