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Frigyes Nemes on behalf of the TOTEM experiment CERN* Diffraction 2016 Acireale, Sicily, Italy 2016, September 2. – 8. *Also at Wigner RCP, Budapest, Hungary

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Page 1: Frigyes Nemes - Agenda (Indico) · Frigyes Nemes on behalf of the TOTEM experiment CERN* Diffraction 2016 Acireale, Sicily, Italy 2016, September 2. –8. *Also at Wigner RCP, Budapest,

Frigyes Nemes on behalf of the TOTEM experimentCERN*

Diffraction 2016

Acireale, Sicily, Italy

2016, September 2. – 8.

*Also at Wigner RCP, Budapest, Hungary

Page 2: Frigyes Nemes - Agenda (Indico) · Frigyes Nemes on behalf of the TOTEM experiment CERN* Diffraction 2016 Acireale, Sicily, Italy 2016, September 2. –8. *Also at Wigner RCP, Budapest,

T1: 3.1 < |h| < 4.7, pT > 100 MeV

T2: 5.3 < |h| < 6.5, pT > 40 MeV

T1 T2 CASTOR (CMS)

10.5 m

14 m

Diffraction 2016 2-8/09/2016 2Frigyes Nemes, TOTEM

Only Run I

Page 3: Frigyes Nemes - Agenda (Indico) · Frigyes Nemes on behalf of the TOTEM experiment CERN* Diffraction 2016 Acireale, Sicily, Italy 2016, September 2. –8. *Also at Wigner RCP, Budapest,

Properties:

• Installed inside CMS at 7.5 to 10.5 m from IP5

• There is one telescope on each side of IP5

• Each telescope consists of two quarters

• The quarters are formed by 5 equally spacedplanes

• The planes contain 3 trapezoidal CSC detectors, each covering 60 ̐ in azimuth

• Cathode Strip Chamber: gaseous detector with3 read-out coordinates (at 60 ̐ wrt. each other)

Diffraction 2016 2-8/09/2016 Frigyes Nemes, TOTEM 3

Page 4: Frigyes Nemes - Agenda (Indico) · Frigyes Nemes on behalf of the TOTEM experiment CERN* Diffraction 2016 Acireale, Sicily, Italy 2016, September 2. –8. *Also at Wigner RCP, Budapest,

Properties:

• Installed inside CMS shielding between HF and Castor calorimeters

• Centered around 13.5 m from IP5

• There is one telescope on each side of IP5

• Each telescope contains two quarters

• Quarters formed by 10 semi-circularplanes, assembled in 5 back-to-backmounted pairs

• Planes equipped with a Gas Electron Multiplierdetector

• Gaseous detector, electron multiplication by 3 perforated foils (2 mm separation)

• radial segmentation: strips (resolution ≈ 0.15 mm)

Diffraction 2016 2-8/09/2016 Frigyes Nemes, TOTEM 4

Page 5: Frigyes Nemes - Agenda (Indico) · Frigyes Nemes on behalf of the TOTEM experiment CERN* Diffraction 2016 Acireale, Sicily, Italy 2016, September 2. –8. *Also at Wigner RCP, Budapest,

RP stations:

• 2 units (Near, Far) at about distance

• 10 m (RP210)

• 5 m (RP220)

• Unit: 3 moveable RP to detect small proton scattering angles (few µrad)

• Overlapping detectors: relative alignment

• BPMs installed

Horizontal RP

RP unit: 2 vertical, 1 horizontal pot + BPM

BPMVertical RPs

Diffraction 2016 2-8/09/2016

5

Frigyes Nemes, TOTEM

1 Roman Pot10 planes of edgeless detectors

3.5 cm

Si edgeless detector

Page 6: Frigyes Nemes - Agenda (Indico) · Frigyes Nemes on behalf of the TOTEM experiment CERN* Diffraction 2016 Acireale, Sicily, Italy 2016, September 2. –8. *Also at Wigner RCP, Budapest,

Diffraction 2016 2-8/09/2016 Frigyes Nemes, TOTEM 6

Proton transport description:

Transport matrix from MAD-X (ξ = Δp/p momentum loss)

*

*

*

*

*

4241

3231

2423

1413

10000 y

x

yyy

yyy

xxx

xxx

RP

y

x

y

x

DLvmm

DLvmm

DmmLv

DmmLv

y

x

Measured

Kinematics reconstruction of elastic protons per arm (arms are averaged):

*

1

xds

dvΘ

ds

dLΘ x

xx*

x

Fy

F

Ny

N*

yL

y

L

,,2

1

2*2*2

yxpt

s: distance from IP5 (*≡IP5)

Page 7: Frigyes Nemes - Agenda (Indico) · Frigyes Nemes on behalf of the TOTEM experiment CERN* Diffraction 2016 Acireale, Sicily, Italy 2016, September 2. –8. *Also at Wigner RCP, Budapest,

Diffraction 2016 2-8/09/2016 Frigyes Nemes, TOTEM 7

List of TOTEM publications

http://totem.web.cern.ch/Totem/publ_new.html

Page 8: Frigyes Nemes - Agenda (Indico) · Frigyes Nemes on behalf of the TOTEM experiment CERN* Diffraction 2016 Acireale, Sicily, Italy 2016, September 2. –8. *Also at Wigner RCP, Budapest,

Momentum conservation is required in elastic events:

• Published in EPL 95 (2011) 41001

Diffraction 2016 2-8/09/2016 8Frigyes Nemes, TOTEM

Horizontally… …and vertically

Spread agrees with beam divergence (17-18 μrad)

)(/)( ** sx

From Liouville’s theorem, ε: emittance

Page 9: Frigyes Nemes - Agenda (Indico) · Frigyes Nemes on behalf of the TOTEM experiment CERN* Diffraction 2016 Acireale, Sicily, Italy 2016, September 2. –8. *Also at Wigner RCP, Budapest,

Published in EPL 95 (2011) 41001:

• |t| range spans from 0.36 to 2.5 GeV2

• Below |t| = 0.47 GeV2 exponential e-B|t| behavior

• Dip moves to lower |t|, proton becomes “larger“

• 1.5 - 2.5 GeV2 power low behavior |t|-n

Diffraction 2016 2-8/09/2016 9Frigyes Nemes, TOTEM

ISR

The measured dσ/dt compared with predictions of several models

Page 10: Frigyes Nemes - Agenda (Indico) · Frigyes Nemes on behalf of the TOTEM experiment CERN* Diffraction 2016 Acireale, Sicily, Italy 2016, September 2. –8. *Also at Wigner RCP, Budapest,

Properties:• Ly ≈ 264 m• Slope B confirms that it increases with √s

• Total cross-section with optical theorem

• ρ value from COMPETE:

• Compatible results, published in:EPL 96 (2011) 21002EPL 101(2013) 21002

1

16

0

el

2

2

2

tot

tdt

dc

01.0

08.014.0

Diffraction 2016 2-8/09/2016 Frigyes Nemes, TOTEM 10

322

min

fullsyststattot

fullsyst

statinel

syststatsyststatel

syststatsyststat

2-

0

syststatsyststat

2-

beam

105102GeV

2.26.988.22.03.98mb

26.115.736.05.73mb

07.103.043.252.12.08.24mb

239.04.5067.265.17.503GeV mb

27.003.089.19 3.02.01.20GeV

510distance RP

3.1

8.1

t

dt

d

B

t

0Im

Re

t

H

H

A

A

Page 11: Frigyes Nemes - Agenda (Indico) · Frigyes Nemes on behalf of the TOTEM experiment CERN* Diffraction 2016 Acireale, Sicily, Italy 2016, September 2. –8. *Also at Wigner RCP, Budapest,

RP@ 10 σbeam size@RP

(RP @ 6.5, 5.5, 4.8 σbeam size@RP )

Diffraction 2016 2-8/09/2016 Frigyes Nemes, TOTEM 11

EPL 101(2013) 21002

EPL 95 (2011) 41001 (β* = 3.5 m)

EPL 96 (2011) 21002 (β* = 90 m)

EPL 101 (2013) 2100 (β* = 90 m)

Page 12: Frigyes Nemes - Agenda (Indico) · Frigyes Nemes on behalf of the TOTEM experiment CERN* Diffraction 2016 Acireale, Sicily, Italy 2016, September 2. –8. *Also at Wigner RCP, Budapest,

Trigger: at least one track in T2

• 95 % of inelastic events

1. Raw rate: event counting with T2

Experimental corrections: trigger and reconstruction inefficiencies,beam-gas event suppression, pile-up

2. Visible rate: visible with T2 in perfect conditions

Estimation of events with no tracks in T2: T1-only events, events withgap over T2, low-mass diffraction

3. Physics rate: true rate of inelastic events– Only one major Monte-Carlo-based correction: low-mass diffraction (which

can be constrained from data, 6.31 mb upper limit for Mx < 3.4 GeV)

4. Cross-section: uses CMS luminosity measurement

Diffraction 2016 2-8/09/2016 Frigyes Nemes, TOTEM 12

EPL 101 (2013) 21003

inel = 73.7 ± 3.4 mb

Page 13: Frigyes Nemes - Agenda (Indico) · Frigyes Nemes on behalf of the TOTEM experiment CERN* Diffraction 2016 Acireale, Sicily, Italy 2016, September 2. –8. *Also at Wigner RCP, Budapest,

Results:

1. Low luminosity (CMS) + Elastic d/dt + Optical th. ( EPL 96(2011) 21002 )

depends on CMS luminosity for low-L bunches, elastic efficiencies and on ρ

2. High luminosity (CMS) + Elastic + Optical theorem (EPL 101 (2013) 21002)

3. High luminosity (CMS) + Elastic + Inelastic (EPL, 101 (2013) 21004)

minimizes dependence on elastic efficiencies and no dependence on ρ

4. Elastic ratios + Inelastic ratios (T1, T2) + Optical theorem (EPL, 101 (2013) 21004)

Eliminates dependence on luminosity

tot = 98.3 ± 2.8 mb

tot = 98.6 ± 2.2 mb

tot = 99.1 ± 4.3 mb

tot = 98.0 ± 2.5 mb

1

16

0

el

2

2

2

tot

tdt

dc

ineleltot

inelel

0

el

2

2

tot1

16

NN

dt

dN

ct

Diffraction 2016 2-8/09/2016 Frigyes Nemes, TOTEM 13

Page 14: Frigyes Nemes - Agenda (Indico) · Frigyes Nemes on behalf of the TOTEM experiment CERN* Diffraction 2016 Acireale, Sicily, Italy 2016, September 2. –8. *Also at Wigner RCP, Budapest,

Diffraction 2016 2-8/09/2016 Frigyes Nemes, TOTEM 14

Page 15: Frigyes Nemes - Agenda (Indico) · Frigyes Nemes on behalf of the TOTEM experiment CERN* Diffraction 2016 Acireale, Sicily, Italy 2016, September 2. –8. *Also at Wigner RCP, Budapest,

Diffraction 2016 2-8/09/2016 Frigyes Nemes, TOTEM 15

Read more:• EPL 101 (2013) 21004

• Phys. Rev. Lett. 111, 012001 (2013)

σtot

[mb]

σel

[mb]

σinel

[mb]

101.7 ± 2.9 27.1 ± 1.4 74.7 ± 1.7

Page 16: Frigyes Nemes - Agenda (Indico) · Frigyes Nemes on behalf of the TOTEM experiment CERN* Diffraction 2016 Acireale, Sicily, Italy 2016, September 2. –8. *Also at Wigner RCP, Budapest,

Symmetries of the tagged particles’ reconstructed

kinematics:

• High statistics

• Rotational symmetry

• Left-right arm symmetry

Diffraction 2016 2-8/09/2016Frigyes Nemes, TOTEM

16

Left - right symmetry (in background estimation)

Rotational symmetry

Page 17: Frigyes Nemes - Agenda (Indico) · Frigyes Nemes on behalf of the TOTEM experiment CERN* Diffraction 2016 Acireale, Sicily, Italy 2016, September 2. –8. *Also at Wigner RCP, Budapest,

Diffraction 2016 2-8/09/2016 Frigyes Nemes, TOTEM 17

The observed differential cross-section w.r.t. reference exponential:• Fits with different assumptions on hadronic component

• Pure exponential excluded with more than 7σ significance !

)exp( 1tbaAN )exp( 3

3

2

21 tbtbtbaAN

Nb σtot [mb]

2 101.5 ± 2.1

3 101.9 ± 2.1

Page 18: Frigyes Nemes - Agenda (Indico) · Frigyes Nemes on behalf of the TOTEM experiment CERN* Diffraction 2016 Acireale, Sicily, Italy 2016, September 2. –8. *Also at Wigner RCP, Budapest,

Basic properties of the data:

• RP detectors at about 3 σbeam

• |t|min = 6 10-4 GeV2

Analysis aims:

• Measure dσel/dt at the smallestpossible |t|

• AC+H= Coulomb + Hadronic +Interference terms

• Interference: the phase of hadronicamplitude appears in

• Determination of ρ became possible:

• Further improve the total cross-sectionσtot measurement

Diffraction 2016 2-8/09/2016 Frigyes Nemes, TOTEM 18

0Im

Re

t

H

H

A

A

2

HCAdt

d

Page 19: Frigyes Nemes - Agenda (Indico) · Frigyes Nemes on behalf of the TOTEM experiment CERN* Diffraction 2016 Acireale, Sicily, Italy 2016, September 2. –8. *Also at Wigner RCP, Budapest,

Diffraction 2016 2-8/09/2016 Frigyes Nemes, TOTEM 19

Purely exponential hadronic amplitude:• Constant phase: excluded• Peripheral phase

o Disfavoured ρ value is not consistent with theory Theoretical arguments next to non-

exp. hadronic amplitude

Non-exponential hadronic amplitude:• Both peripheral and constant phase compatible

with datao Centrality not necessity

Nb = 1

Nb = 3

Page 20: Frigyes Nemes - Agenda (Indico) · Frigyes Nemes on behalf of the TOTEM experiment CERN* Diffraction 2016 Acireale, Sicily, Italy 2016, September 2. –8. *Also at Wigner RCP, Budapest,

Diffraction 2016 2-8/09/2016 Frigyes Nemes, TOTEM 20

First determination of ρ at LHC from Coulomb-hadronic interference:• Same ρ value with central and peripheral models• At s=13 TeV a ρ measurement is planned with higher statistics

Hadronic phase σtot [mb]

Central 102.9 ± 2.3

Peripheral 103.0 ± 2.3

Total cross-section measurement• Compatible with previous TOTEM measurements• About 1 mb increase due to CNI

Accepted for publication: http://cds.cern.ch/record/2114603

Page 21: Frigyes Nemes - Agenda (Indico) · Frigyes Nemes on behalf of the TOTEM experiment CERN* Diffraction 2016 Acireale, Sicily, Italy 2016, September 2. –8. *Also at Wigner RCP, Budapest,

Diffraction 2016 2-8/09/2016 Frigyes Nemes, TOTEM 21

Page 22: Frigyes Nemes - Agenda (Indico) · Frigyes Nemes on behalf of the TOTEM experiment CERN* Diffraction 2016 Acireale, Sicily, Italy 2016, September 2. –8. *Also at Wigner RCP, Budapest,

Note:

• Large amount of data (trigger rate 50× w.r.t. Run I)

Diffraction 2016 2-8/09/2016 Frigyes Nemes, TOTEM 22

Non-exponential part is visible at low-|t|

No structures at high-|t|:rules out several models

Page 23: Frigyes Nemes - Agenda (Indico) · Frigyes Nemes on behalf of the TOTEM experiment CERN* Diffraction 2016 Acireale, Sicily, Italy 2016, September 2. –8. *Also at Wigner RCP, Budapest,

Diffraction 2016 2-8/09/2016 Frigyes Nemes, TOTEM 23

LyLy [m]

Odderon: (hypothetical) partner of Pomeron in Regge-theory

Possible searches at the LHC:

• Structures in dσ/dt where Pomeron contribution is small

– High-t: 13 TeV TOTEM data does not show structures

– Low-t: shift in value of ρ parameter with CNI

• At 13 TeV means special optics (β* = 2500 m)

• About 1 week data taking time (approved in 2016)

Page 24: Frigyes Nemes - Agenda (Indico) · Frigyes Nemes on behalf of the TOTEM experiment CERN* Diffraction 2016 Acireale, Sicily, Italy 2016, September 2. –8. *Also at Wigner RCP, Budapest,

Diffraction 2016 2-8/09/2016 Frigyes Nemes, TOTEM 24

Page 25: Frigyes Nemes - Agenda (Indico) · Frigyes Nemes on behalf of the TOTEM experiment CERN* Diffraction 2016 Acireale, Sicily, Italy 2016, September 2. –8. *Also at Wigner RCP, Budapest,

Low mass diffraction

Very high mass ( ξ > 2.5 % )

Diffraction 2016 2-8/09/2016 Frigyes Nemes, TOTEM 25

MX2 = s

Rapidity Gap

Dh = -ln

RP RPT2 T2

IPsector 45 sector 56

=Dp/p

h

RP RPT2 T2

IPsector 45 sector 56

h

MX2 = s

Rapidity Gap

Dh = -ln

• SD events are triggered with T2, only 1 proton required in RP

• Double determination of ξ ≈ e -Δη

– From RPs (ξ ≈ x / Dx and optics non-linearity Ly(ξ), etc.)

– From rapidity gap in T1/T2

– MX 2 ≈ s · ξ

• Available data

– 7 TeV: TOTEM standalone analysis in progress

– 8 and 13 TeV: common data with CMS

Page 26: Frigyes Nemes - Agenda (Indico) · Frigyes Nemes on behalf of the TOTEM experiment CERN* Diffraction 2016 Acireale, Sicily, Italy 2016, September 2. –8. *Also at Wigner RCP, Budapest,

Corrections included:

• Trigger efficiency

• Reconstruction efficiency

• Proton acceptance

• Background subtraction

• Extrapolation to t = 0

Missing corrections:

• ξ – resolution

• Beam divergence effects

Estimated uncertainty:

• B ~ 15 %, σ ~ 20 %

Very preliminary result:

• σSD = 6.5 ± 1.3 mb

• 3.4 < MSD < 1100 GeV

• Very-high masses: ongoing

Diffraction 2016 2-8/09/2016 Frigyes Nemes, TOTEM 26

teCdt

d B

Page 27: Frigyes Nemes - Agenda (Indico) · Frigyes Nemes on behalf of the TOTEM experiment CERN* Diffraction 2016 Acireale, Sicily, Italy 2016, September 2. –8. *Also at Wigner RCP, Budapest,

Event selection:

• T1 veto + 2 T2 topology

Properties:

• ηmin visible to TOTEM T2: 4.7 < |ηmin | < 6.5 ≡ 3.4 < Mdiff < 8 GeV

• Non-diff. bkg.: control sample 2 T1 + 2 T2 events

• Single diff. bkg. T1 veto + 1 T2 and proton in the RP

Diffraction 2016 2-8/09/2016 Frigyes Nemes, TOTEM 27

CMS

Page 28: Frigyes Nemes - Agenda (Indico) · Frigyes Nemes on behalf of the TOTEM experiment CERN* Diffraction 2016 Acireale, Sicily, Italy 2016, September 2. –8. *Also at Wigner RCP, Budapest,

Results from 7 TeV data:

• Phys. Rev. Lett. 111, 262001 (2013)

• Improvement expected with the8 TeV data, including also theCMS information

MC comparisons:

Diffraction 2016 2-8/09/2016 Frigyes Nemes, TOTEM 28

b 25116 )5.67.4( min

h

DD

Page 29: Frigyes Nemes - Agenda (Indico) · Frigyes Nemes on behalf of the TOTEM experiment CERN* Diffraction 2016 Acireale, Sicily, Italy 2016, September 2. –8. *Also at Wigner RCP, Budapest,

Very forward measurement with T2 :

• Published EPL, 98 (2012) 31002

• Visible cross section measured on data: ~ 94 % σinel

• Diffractive mass Mdiff > 3.4 GeV

Main contributions to the systematic uncertainty (≈ 10%)

• Subtraction of secondary particles (80 % of all tracks)

• Track efficiency

• Misalignment uncertainties

dN

ch/d

h

Diffraction 2016 2-8/09/2016Frigyes Nemes, TOTEM

29

Combined with other LHC exp.

Page 31: Frigyes Nemes - Agenda (Indico) · Frigyes Nemes on behalf of the TOTEM experiment CERN* Diffraction 2016 Acireale, Sicily, Italy 2016, September 2. –8. *Also at Wigner RCP, Budapest,

Diffraction 2016 2-8/09/2016 Frigyes Nemes, TOTEM 31

Available data:

• 7 TeV: TOTEM only, analysis started

• 8 TeV: common data with CMS, analysis started

• 13 TeV: common data with CMS

Experimental challenge: background (pileup ES/beam halo + inelastic)

• Anti-elastic cuts: anti-collinearity, …

1=Dp1/p1

2=Dp2/p2

Page 32: Frigyes Nemes - Agenda (Indico) · Frigyes Nemes on behalf of the TOTEM experiment CERN* Diffraction 2016 Acireale, Sicily, Italy 2016, September 2. –8. *Also at Wigner RCP, Budapest,

Correlation between leading protons and T2:

RP RPT2 T2

IPsector 45 sector 56

low ξ high ξ

1=Dp1/p1

2=Dp2/p2

Diffraction 2016 2-8/09/2016 Frigyes Nemes, TOTEM 32

Page 33: Frigyes Nemes - Agenda (Indico) · Frigyes Nemes on behalf of the TOTEM experiment CERN* Diffraction 2016 Acireale, Sicily, Italy 2016, September 2. –8. *Also at Wigner RCP, Budapest,

σCD estimation:

mb 1

)(

21

20 0

21

2,1

21

2

21

D

dtdt

ddtdt

eeCdtdt

d

CDCD

BtBtCD

Available data s = 7 TeV and β* = 90 m optics:

• Trigger selection: 2 × RP

• Nearly complete ξ - acceptance

• Background: elastic, beam-halo + inelastic– Elastic: anti-elastic cuts, e.g. forbidden topologies (top-top, bottom-bottom)

– Beam-halo: |y| > 11 × σbeam → halo is negligible

B = 7.8 1.4 GeV-2

Single arm CD event rate in RPintegrated , acceptance corrected

Diffraction 2016 2-8/09/2016 Frigyes Nemes, TOTEM 33

TOTEM Preliminary

Page 34: Frigyes Nemes - Agenda (Indico) · Frigyes Nemes on behalf of the TOTEM experiment CERN* Diffraction 2016 Acireale, Sicily, Italy 2016, September 2. –8. *Also at Wigner RCP, Budapest,

Diffraction 2016 2-8/09/2016 Frigyes Nemes, TOTEM 34

TOTEM + CMS unprecedented properties:

• Double arm proton detection

• Mass of diffractive system X is double determined– By TOTEM Roman Pots MX

2 = s ξ1 ξ2

– By CMS

Analysis examples:

• Studies of glueball candidates

• Exclusive dijets: mainly gg (pT > 30 GeV)

• Exclusive J/ψ, Z, W production: O (10 pb – 10 nb)

• Search for missing mass signals ofO (pb) → SUSY searches

Page 35: Frigyes Nemes - Agenda (Indico) · Frigyes Nemes on behalf of the TOTEM experiment CERN* Diffraction 2016 Acireale, Sicily, Italy 2016, September 2. –8. *Also at Wigner RCP, Budapest,

Diffraction 2016 2-8/09/2016 Frigyes Nemes, TOTEM 35

Available data β* = 90 m:

• 8 TeV, Jul 2012, L = 1 nb-1 : proof of principle

• 13 TeV, Oct 2015, L = 0.4 pb-1 : should allow full production and decay characterisation

2015 data:

• CMS + TOTEM: trigger exchange, independent DAQ, offline data merging

• Trigger: RP double arm & T2 veto & at least one track in CMS

• Analysis strategy – verify the following glueball conditions

– Resonance enhancement with increasing collision energy

– Final states branching ratio to π π, KK, ..., with equi-flavour partitioning selection rules(or with proportionality of gluon coupling to quarks)

– Suppression of photon-photon channel (in production and final state)

Page 36: Frigyes Nemes - Agenda (Indico) · Frigyes Nemes on behalf of the TOTEM experiment CERN* Diffraction 2016 Acireale, Sicily, Italy 2016, September 2. –8. *Also at Wigner RCP, Budapest,

• Upgrade projects: interest in lower cross-section processes

• Higher luminosity needed → Higher pile-up

– Timing: association of RP proton vertex with CMS vertex

– Pixel detectors: more tracks in RPs

CT-PPS = CMS-TOTEM Precision Proton Spectrometer

Diffraction 2016 2-8/09/2016 Frigyes Nemes, TOTEM 36

Project CT-PPS(see F. Ferro’s talk on Wednesday)

Timing in vertical RP

Optics Low (LHC standard) β*= 0.4 m High lumi β*= 90 m

RP detectors Horizontal Vertical

Tracking Si strip in 2016 (~ 8 fb-1)3D pixel (10 μm) to be installed

Current Si strip (20 μm/RP)

Timing Diamond (100 ps/plane), installed, soon will be used

Page 37: Frigyes Nemes - Agenda (Indico) · Frigyes Nemes on behalf of the TOTEM experiment CERN* Diffraction 2016 Acireale, Sicily, Italy 2016, September 2. –8. *Also at Wigner RCP, Budapest,

• Performance in Run II

– All detectors functional

– RPs equipped with RF shields (less impedance) close approach possible

– DAQ throughput increased 50 w.r.t. Run I (zero-suppression)

• Many analyses ongoing

– Run I and Run II

– TOTEM standalone, TOTEM + CMS

• Upgrade projects

– Timing in vertical RPs (diamonds)

– CT-PPS (pixel tracking, timing with fast silicon, diamond)

• Priorities for 2016

– Glueball analysis of 2015 data

– TOTEM special run: β* = 2.5 km, Odderon searches via CNI

– CT-PPS runs with LHC standard optics: di-photon searches with existing RPs

Diffraction 2016 2-8/09/2016 Frigyes Nemes, TOTEM 37

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Diffraction 2016 2-8/09/2016 Frigyes Nemes, TOTEM 38

Page 39: Frigyes Nemes - Agenda (Indico) · Frigyes Nemes on behalf of the TOTEM experiment CERN* Diffraction 2016 Acireale, Sicily, Italy 2016, September 2. –8. *Also at Wigner RCP, Budapest,

Diffraction 2016 2-8/09/2016 Frigyes Nemes, TOTEM 39

Page 40: Frigyes Nemes - Agenda (Indico) · Frigyes Nemes on behalf of the TOTEM experiment CERN* Diffraction 2016 Acireale, Sicily, Italy 2016, September 2. –8. *Also at Wigner RCP, Budapest,

Diffraction 2016 2-8/09/2016 Frigyes Nemes, TOTEM 40

Different formulations of the interference phenomenon:• Simplified West-Yennie (SWY)

o Based on QFTo Simplifications: constant slope and constant hadronic phase

• Cahn or Kundrát-Lokajicek (KL) modelo Eikonal frameworko No explicit simplifications

The t-dependence of the two considered hadronic phase model families:

Page 41: Frigyes Nemes - Agenda (Indico) · Frigyes Nemes on behalf of the TOTEM experiment CERN* Diffraction 2016 Acireale, Sicily, Italy 2016, September 2. –8. *Also at Wigner RCP, Budapest,

Machine imperfections alter the optics:

• Strength conversion error, σ(B)/B ≈ 10-3

• Beam momentum offset, σ(p)/p ≈ 10-3

• Other factors…

Diffraction 2016 2-8/09/2016 Frigyes Nemes, TOTEM 41

2*2*2

yxpt

→ Precise model of the LHC optics is indispensable!

Novel method from TOTEM:

• Use measured proton data from RPs

• http://iopscience.iop.org/1367-2630/16/10/103041/

Relative error distribution

before and

after optics estimation β* = 3.5 m

Page 42: Frigyes Nemes - Agenda (Indico) · Frigyes Nemes on behalf of the TOTEM experiment CERN* Diffraction 2016 Acireale, Sicily, Italy 2016, September 2. –8. *Also at Wigner RCP, Budapest,

On the basis of constraints R1-R10 the optics can be estimated:

Diffraction 2016 2-8/09/2016 Frigyes Nemes, TOTEM 42

RPb2,y,

RPb1,y,

RPb2,

RPb1,

2L

L

y

yR

RPb1,y,

RPb1,y,

RPb1,

RPb1,y,

3L

ds

dL

y

ΘR

/dsdL

L

Θ

xR

RPb1,x,

RPb1,x,

RPb1,x,

RPb1,

5 near_potsb1,y,

near_potsb1,14,

RPb1,

RPb1,

7L

m

y

xR

R3,4

R7,8,9,10

R5,6

2

Design LHC

10

1

2

calculated,measured,

2 ))(/)(( i

iii RRR

Measured ratiosR1-R10

Calculated ratiosR1-R10

dLx/ds, Ly

Comparison

R1

R2

Refine machine settings• 2x6 quad. magnet strength• 2x6 quad. rotation• Momentum of 2 beams