jan kašpar onbehalfofthetotemcollaboration

TOTEM

Jan Kašparon behalf of the TOTEM collaboration

QCD at Cosmic Energies – VII19 May, 2016

Outline

• TOTEM projects and physics programme

• detector apparatus,principle of proton measurement

• physics analyses and results: TOTEM alone

• physics analyses and results: TOTEM + CMS

• upgrades, outlook for 2016

list of TOTEM publications:http://totem.web.cern.ch/Totem/publ new.html

Jan Kašpar QCD at Cosmic Energies – VII 19 May, 2016 2

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

TOTEM projects and physics programme

• TOTEM◦ LHC experiment dedicated to measurement of:

total cross-section, elastic scattering and diffractive processes

◦ common features: rapidity gaps, particles in very forward region, survivingprotons⇒ special detectors

• TOTEM + CMS◦ both experiments at LHC Interaction Point 5◦ excellent pseudorapidity coverage: optimal for hard diffraction studies◦ cooperation mode: independent experiments, exchange of triggers

• CT-PPS (CMS-TOTEM Precision Proton Spectrometer)◦ all subdetectors fully integrated under CMS◦ dedicated detectors for high-pileup environment (timing, pixels instead ofstrips)


Detector apparatus

• Inelastic telescopes T1 and T2: charged particles from inelastic collisions

T1 T2

CMS

9m

13.5m

• T1: 3.1 < |η| < 4.7,pT > 100MeV

• T2: 5.3 < |η| < 6.5,pT > 40MeV

• Roman Pots (RP): elastic and diffractive protons close to outgoing beamRP RPRP

◦ station at 147m in Run I→ station 210m in Run II

• all detectors: symmetric about IP5, trigger capable, radiation tolerantJan Kašpar QCD at Cosmic Energies – VII 19 May, 2016 4

Telescope 1 (T1)

• installed inside CMS end-caps• at 7.5 to 10.5 m from the IP• one telescope on each side of IP• each telescope consists of two quarters

• each quarter formed by 5 planes equally spacedalong beam

• each plane consists of 3 trapezoidal CSC detec-

tors, each covering 60 ◦ in azimuth• Cathode Strip Chamber: gaseous detector with3 read-out coordinates (at 60 ◦ wrt. each other)


Telescope 2 (T2)

• installed inside CMS shielding between HFand Castor calorimeters

• centred about 13.5 m from the IP• one telescope on each side of IP• each telescope consists of two quarters

• each quarter formed by 10 semi-circular planes,assembled in 5 back-to-back mounted pairs

• each plane equipped with a Gas Electron Multi-

plier detector◦ gaseous detector, electron multiplication by 3perforated foils (2 mm separation)

◦ radial segmentation: strips (resolution≈ 0.15 mm)

◦ coarse radial×azimuthal segmentation: pads(for triggering, azimuthal resolution 0.8 ◦)


Roman Pots (RPs)

• stations installed at ±220 m in the outgoing LHC beam-pipe• each station has two units, separated by ≈ 5 m

horizontal RP BPM

top RP

bottom RP

• each unit contains 3 Roman Pots: top, bottom and horizontal• Roman Pot = movable beam-pipe insertion◦ beam unstable⇒ RPs retracted to safe position◦ beam stable⇒ RPs as close to beam as reasonable

• typical approach: 10 σbeam (record 3 σbeam)

• Roman Pot: container for sensors• LS1: improved RF shield ⇒ possible close approach to high-intensity beam


“Edgeless” silicon sensors

• each RP contains a package of 10 silicon sensors• 5 pairs of back-to-back mounted strip sensors

VFAT chips

cut edge

strip

dire

ction

• custom developed “edgeless” sensors⇒ insensitive edge ≈ 50 µm (standard about 1 mm)

• single-sided p+-n• 512 strips at pitch of 66 µm, at 45 ◦ wrt. cut edge• operated at ≈ −20 ◦C, bias voltage ≈ 100 V


Proton measurement with RPs

• proton transport: described as in linear optics

IPs ≡ beam axis

x

LHC magnet lattice⇒ accelerator optics RP station

p∗p

x∗ ϑ∗xxN

xFϑx

x

θx

y

θy

ξ

RP

=

vx Lx · · Dx

· · · · ·vy Ly · · Dy

· · · · ·· · · · 1

︸︷︷︸product from all lattice elements

x∗

θ∗xy∗

θ∗yξ

IP

θ∗x, θ∗y: scattering anglesx∗, y∗: vertexξ = ∆p/p: momentum loss

optical functions:effective length Lmagnification vdispersion D

• proton reconstruction: inverted transport RPs −→ IP◦ optical parameters functions of ξ⇒ reconstruction is non-linear problem◦ good knowledge of optics is crucial


LHC optics

• simulation of central diffraction for 2 different opticslow β∗ (LHC standard)

Lx ≈ 1.7 m, Ly ≈ 14 m, Dx ≈ 8 cmdiffractive protons in horizontal RPs

β∗ = 90 m (special for TOTEM)Lx ≈ 0, Ly ≈ 260 m, Dx ≈ 4 cm

diffractive protons in vertical RPs

• optics typically “labelled” by β∗ ≡ betatron function at IP

◦ beam width:√εβ, ε: beam emittance

◦ beam angular divergence:√ε/β

◦ luminosity ∝ (beam width at IP)−2 ∝ 1/β∗


Typical run scenarios

t ≈ −p2θ2: four-momentum transfer squaredξ = ∆p/p: fractional momentum loss

10−4 10−2 100

|t| (GeV2)

10−4

10−3

10−2

10−1

ξ

00.10.20.30.40.50.60.70.80.91

10−4 10−2 100

|t| (GeV2)

10−4

10−3

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10−1

ξ

00.10.20.30.40.50.60.70.80.91

10−4 10−2 100

|t| (GeV2)

10−4

10−3

10−2

10−1

ξ

00.10.20.30.40.50.60.70.80.91

β∗ = 0.55 mL ≈ 1033 cm−2s−1

elastic scattering: high |t|

diffraction: ξ & 0.03, lowcross-section processes

medium β∗ = 90 mL ≈ 1028 cm−2s−1

elastic scattering: low to mid|t|

diffraction: any ξ for|t| & 0.01 GeV2

high β∗ = 1535 mL ≈ 1027 cm−2s−1

elastic scattering: very low |t|(Coulomb-nuclearinterference)

details depend on RP approach to beam and precise opticsJan Kašpar QCD at Cosmic Energies – VII 19 May, 2016 11

Elastic scattering : p+ p→ p+ p

• selection: two anti-collinear protons from the same vertex• (almost) purely data-driven analysis• data overview (selection), gray = preliminary

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√s = 2.76 TeV

√s = 7 TeV

√s = 8 TeV

√s = 13 TeV

PRELIMINARYPRELIMINARY

PRELIMIN

ARY

√s = 2.76 TeV (arbitrary normalisation)

β∗ = 11 m, VERY PRELIMINARY!√s = 7 TeV

β∗ = 3.5 mβ∗ = 90 m√

s = 8 TeV (scaled 10×)β∗ = 90 m, PRELIMINARY!β∗ = 90 mβ∗ = 1000 m√

s = 13 TeV (arbitrary normalisation)β∗ = 90 m, VERY PRELIMINARY!

• different |t| probe different physics regimes – from lowest to highest |t|:Coulomb interference, diffractive cone, dip-bump, transition to pQCD


Elastic scattering : Trends

(gray = preliminary)

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√s = 8 TeV

√s = 13 TeVPRELIM

INARYPRELIMINARY

PRELIMINARY

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s (GeV)

√s

=2.

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=13

TeV

ppp̄pTOTEMATLAS-ALFAfit quadraticin ln s

• dip position

◦ √s = 8 TeV: limited statistics◦ √s = 7→ 13 TeV: dip moves to lower |t|– 13 TeV results preliminary! (the yet missing unfolding correction likely tomove the dip to lower |t|)

• forward slope B = ddt ln

dσdt

∣∣∣t=0

◦ increase wrt. previous experimentsJan Kašpar QCD at Cosmic Energies – VII 19 May, 2016 13

Elastic scattering : Non-exponentiality at low |t|

• diffraction cone: “looks almost exponential”◦ magnify deviations⇒ plot (dσ/dt − ref. exp.)/ref. exp.• β∗ = 90 m measurements at different energies (stat. unc. only):

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ref)/

ref,

ref=

503e−

19.9|t|

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√s = 7 TeV

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(dσ/dt−

ref)/

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ref=

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.38|

t|

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√s = 8 TeV

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ref

ref

,re

f=1.

336×

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e−20|t|

0 0.05 0.1 0.15 0.2|t| (GeV2)

√s = 13 TeV

• non-exponentiality observed at 8 and 13 TeV!◦ 8 TeV: 7 σ significance −→◦ 13 TeV: preliminary results◦ non-exponentiality of observed cross-section:dσ/dt = nuclear + Coulomb + interference

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efre

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=52

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.39|t|

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data, statistical uncertaintiesfull systematic uncertainty bandsyst. unc. band without normalisation

Nb = 1Nb = 2Nb = 3


Elastic scattering : Coulomb interference

• 8 TeV data with β∗ = 1000 m optics◦ RPs very close to the beam: ≈ 3 σbeam◦ |t|min ≈ 6 · 10−4 GeV2

103

dσ/

dt

(mb/

GeV

2 )

0 0.005 0.01 0.015 0.02|t| (GeV2)

Coulomb-hadronic interference

TOTEM dataCoulomb standalonehadronic standaloneCoulomb and hadronic combined

A data fit at√

s = 8 TeV


Elastic scattering : Coulomb interference

• observed cross-section

dσdt ∝

∣∣∣∣∣∣∣∣∣∣∣∣

+ · · ·

︸︷︷︸Coulombamplitude

+ FH

︸︷︷︸hadronicamplitude

+ FH + · · ·

︸︷︷︸“interference”terms

∣∣∣∣∣∣∣∣∣∣∣∣

2

◦ 2 meanings of “interference”: sum of amplitudes, additional terms• interference formula = summation for practical applications◦ simplified West-Yennie (SWY): QFT framework, traditional but heavy simplifi-

cations (constant hadronic phase, constant slope)

◦ Cahn or Kundrát-Lokajíček (KL): eikonal framework, no explicit simplifications• interference⇒ phase of hadronic amplitude exposed in cross-section◦ phase t-dependence needs to be considered in analysis◦ constraints from data⇒ determination of ρ parameter

ρ = <AN/=AN∣∣∣t=0


Elastic scattering : Coulomb interference – Analysis strategy

central question:observed non-exponentiality – due to hadronic, Coulomb or both?

• fits with 2 different assumptions on hadronic component◦ purely-exponential – non-exponentiality due to Coulomb (+interference)→ |AN| = a exp(b1t)◦ flexible enough to describe non-exponentiality even without Coulomb→ |AN| = a exp(b1t + b2t

2 + b3t3)

• role of hadronic phase t-dependence?◦ largest impact: rate of change at low |t|– same quantity controls behaviour in impact-parameter space◦ considered two families: central (black ↓), peripheral (blue ↓)

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]

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|P(b

)|2

0 0.5 1 1.5 2 2.5 3b [fm]

√〈b2〉el

√〈b2〉inel

√〈b2〉tot

Cahn/KL, constant: 0.88 fm 1.38 fm 1.26 fmCahn/KL, peripheral: 1.99 fm 0.79 fm 1.23 fm


Elastic scattering : Coulomb interference – Fits

β ∗ = 1000 m:data with stat. unc.full syst. unc.syst. unc. w/o norm.

β ∗ = 90 m:data with stat. unc.full syst. unc.syst. unc. w/o norm.

fits:SWY, constantCahn/KL, constantCahn/KL, peripheral

0 0.05 0.1 0.15 0.2|t | [GeV2]

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t−re

fre

f,

ref

=52

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e−19.3

9|t|

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⇐ purely-exponential hadronic amplitude◦ constant phase excluded (with both SWY andKL formulae) ⇒ application of SWY formulaexcluded too

◦ peripheral phase not excluded by data, butdisfavoured

– ρ value outside a consistent pattern ofother fits and theoretical predictions

– number of theoretical reasons fornon-exponential hadronic amplitude

0 0.05 0.1 0.15 0.2|t | [GeV2]

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t−re

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f,

ref

=52

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9|t|

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⇐ non-exponential hadronic amplitude◦ both constant and peripheral phases compat-ible with data⇒ centrality not necessity


Elastic scattering : Coulomb interference – ρ parameter

• √s = 8 TeV: first LHC determination from Coulomb-hadronic interferenceρ = 0.12± 0.03

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s [GeV]

√ s=

13Te

V

pp (PDG)–pp (PDG)COMPETE preferred model (pp)TOTEM indirect at

√s = 7 TeV

this article,√

s = 8 TeV

◦ leading uncertainty: statistics

• plans for √s = 13 TeV: ρ measurement with higher statistics


Elastic scattering : Exclusion power in Run I

• model predictions (prior to Run I) vs. TOTEM data at√s = 7 TeV:

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/dt

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TOTEM:β∗ = 3.5 mβ∗ = 90 m

models:block [06]bourrely [03]islam (lxg) [06,09]jenkovszky [11]petrov (2p) [02]petrov (3p) [02]

√s = 7 TeV

◦ no model compatible with data!

• surprisingly?: little reaction after Run I (statement from 2015)◦ most often: no change at all or simple parameter refit◦ only Islam abandoned one mechanism of large |t| scattering◦ exclusion of physics mechanisms (model independent)?


Elastic scattering : Structures at high |t| ?

• √s = 13 TeV: very preliminary, but already very strong results

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elastic scattering√

s = 13 TeVall 10 σ fills from October 2015O(100 %) statisticsreconstruction from 220N and 220Ftagging cuts at 4 σconservative acceptance correctionno other corrections

elastic scattering√

s = 13 TeVall 10 σ fills from October 2015O(100 %) statisticsreconstruction from 220N and 220Ftagging cuts at 4 σconservative acceptance correctionno other corrections

45 bot – 56 topevents 5.55×108

45 top – 56 botevents 7.82×108

model predictions:

10−710−610−510−410−310−210−1

100101102103

0 1 2 3 410−710−610−510−410−310−210−1

100101102103

dσ/dt

(mb/

GeV

2 )

0 1 2 3 4|t| (GeV2)

Block et al.Bourrely et al.Donnachie et al.Ferreira et al.GodizovIslam et al. (LxG)Jenkovszky et al.Petrov et al. (3P)

√s = 13 TeV

oscillations in almost each model

• high-|t|: no structures!◦ rules out many models◦ rules out physics mechanism: “optical” models◦ physics interpretation: transition between diffractionand pQCD? ⇒ e.g. Donnachie-Landshoff⇒


Inelastic and total cross-section

• inelastic cross-section: event counting with T2 (and T1)◦ 95 % of inelastic events have at least 1 track in the T2 region◦ only one significant MC correction: contribution from low mass diffraction• 3 methods to determine total cross-section

σtot

elastic observables only:

σ2tot =

16π

1 + $21L

dNeldt

∣∣∣∣0

$-independent:

σtot =1L (Nel + Ninel)

luminosity-independent:

σtot =16π

1 + $2dNel/dt|0Nel + Ninel


Cross-section results

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ot(r

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(mb)

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13 TeV

σtot

σinel

σel

p̄p (PDG)pp (PDG)Auger (+ Glauber)ALICEATLAS (ALFA)CMSTOTEM (L indep.)best COMPETE σtot fits11.7 − 1.59 ln s + 0.134 ln2 s

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pp, PDGp̄p, PDGTOTEMATLAS-ALFAfit from EPL 101 (2013) 21004

• √s = 7 TeV: all 3 methods consistent• √s = 8 TeV: results from CNI study superior◦ Coulomb component explicitly separated◦ determined in the same analysis as ρ• √s = 2.76 and 13 TeV analyses ongoingJan Kašpar QCD at Cosmic Energies – VII 19 May, 2016 23

Single diffraction: p+ p→ p+ X

RP RPCMST1 T1T2 T2

• double determination of ξ ≈ e−∆η◦ from RPs◦ from rapidity gap ∆η (T1/T2)• mass of diffractive system: MX =

√sξ

• available data◦ 7 TeV: TOTEM-standalone analysis in progress◦ 8 and 13 TeV: common data with CMS• ξ resolution from RPs: ≈ 0.9 %⇒mass bins given by arms where T1/T2 active


Single diffraction : Preliminary results at 7 TeV


Double diffraction: p+ p→ X + Y

RP RPCMST1 T1T2 T2ηmin

ηmin

• experimental challenge: background (non-diffractive, SD pile-up)◦ sub-sample with signal� background: 2×T2 and T1 veto◦ non-diffractive background: control sample 2×T2 + 2×T1◦ SD background: control sample 1×T2 + 0×T1• cross-section as function of ηmin on both sides◦ challenge: reconstructed ηmin −→ true/generator ηmin⇒ 2 ηmin bins only

• available data◦ 7 TeV: results published◦ 8 and 13 TeV: common data with CMS (improvement expected)


Double diffraction : Results at 7 TeV

• measurement

• comparison to Monte Carlos


Central diffraction: p+ p→ p+ X + p

RP RPCMST1 T1T2 T2

• available data◦ 7 TeV: TOTEM only, analysis started◦ 8 TeV: common data with CMS, analysis started◦ 13 TeV: common data with CMS• β∗ = 90 m: all ξ visible, but resolution ≈ 0.9 %• experimental challenge: background (pileup ES/beam halo + inelastic)◦ anti-elastic cuts: anti-collinearity◦ anti-beam-halo cuts: |y| > 11 mm


Central diffraction : First results at 7 TeV

• |ty| distribution: all ξ values, only acceptance correction

• estimate of σCDd2σCDdt1dt2

= Ce−Bt1e−Bt2

⇓

σCD =0∫

−∞dt1

0∫

−∞dt2 Ce−Bt1e−Bt2 ≈ 1 mb


Forward charged-particle multiplicities

• dNch/dη : mean number of charged particles per event and per unit of pseu-dorapidity• probes (non-)perturbative strong interactions and hadronisation• measurement based on T2◦ ≈ 95 % of inelastic events seen◦ almost all non-diffractive events visible◦ diffraction with MX & 3.4 GeVdetected◦ selection of primary particles:lifetime > 30 ps (LHC convention)

• available data◦ √s = 7 TeV: TOTEM only, published◦ √s = 8 TeV: TOTEM + CMS, TOTEM + shifted vertex, published◦ √s = 13 TeV


Forward charged-particle multiplicities :√s = 7 TeV

↑ NB: each experiment has different eventselection!

• main contributions to systematic uncertainty (≈ 10 %)◦ subtraction of a large fraction of secondaries (about 80 % of all T2 tracks)◦ track efficiency and misalignment uncertainties


Forward charged-particle multiplicities :√s = 8 TeV

• TOTEM + CMS◦ non-single-diffractive enhanced: requiring both hemispheres of T2 on◦ single-diffractive enhanced: requiring only one hemisphere of T2 on

• TOTEM only, with displaced vertex

(z = 11.25 m)


Inelastic event classification

• √s = 8 TeV: analysis in review◦ classes considered: non-diffractive (ND), single diffractive (SD) with protonleft/right, double diffractive (DD)– central diffraction not take into account: low cross-section not worth addedcomplexity

◦ experimental definition of diffraction: rapidity gap ∆η ≥ 3◦ boosted decision tree– ordered binarisation: ND→ SD (left)→ SD (right)→ DD◦ training sample: Pythia 8-4C◦ control samples: Pythia 8-4C+MBR, QGSJET-II-04, Pythia 8-Monash◦ discriminators: ∆η, ηmin, ηmax, NCMS, NT2+, NT2−, ξL, ξR, ...• possible improvement: use of CMS FSC (6 < |η| < 8) ⇒ better distinctionbetween low-mass DD (more forward than T2) and SD with undetected proton• other available data◦ √s = 13 TeV


(Exclusive) central diffraction with CMSp

p

p → RP: ξ1

X → CMS: MX =√

ξ1ξ2s, yX = 12 ln ξ1

ξ2

p → RP: ξ2

• exchange of colour singlets with vacuum quantum numbers⇒ selection rulesfor system X: JPC = 0++, 2++, ...• double-arm proton tagging: mass reach and luminosity depending on optics• event selection via comparison CMS to RP protons:

M(pp) vs. M(CMS) , pT(pp) vs. pT(CMS) , vertex(pp) vs. vertex(CMS)• prediction of rapidity gap from proton ξ: ∆η1,2 = − ln ξ1,2• analysis examples:◦ studies of glueball candidates◦ exclusive dijets: mainly gg (pT > 30GeV: σgg ≈ 100pb)◦ exclusive χc and J/Ψ production: O(10pb− 10nb)◦ search for missing mass signals of O(pb)⇒ SUSY searches


Glueball searches

• CD production at LHC◦ MX = 1 to 4 GeV⇒ x ∼ 10−4 ⇒ pure gluon content◦ Pomeron ∼ colour-less gluon ladder⇒ fusion likely to produce glueballs• 0++ glueball candidates: f0(1500), f0(1710), f0(1370)◦ lattice QCD: m(0++) glueball ∼ 1700(±100) MeV• CMS + TOTEM:◦ both protons measured and tagged by TOTEM◦ effective selection with high purity (pT balance + x-vertexing) in requiredξ-range.◦ CMS tracker: charged particle invariant mass with σ(M) ∼ 20− 30 MeV• available data◦ 8 TeV, β∗ = 90 m, Jul 2012: L ≈ 1 nb−1: proof of principle◦ 13 TeV, β∗ = 90 m, Oct 2015: L ≈ 0.4 pb−1 for (CMS + TOTEM): should allowfull production and decay characterisation


Glueball searches : 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 (increasingly puregluon contribution to CEP)◦ final states branching ratio to ππ, KK, ..., with equi-flavour partitioning selec-tion rules (or with proportionality of gluon coupling to quarks)◦ suppression of photon-photon channel (in production and final state)


Outlook

• upgrade projects: interest in lower cross-section processes⇒ higher luminosity needed⇒ higher pile-up◦ need timing: association of RP proton vertex with CMS vertex◦ need pixels: more tracks in RPs

project CT-PPS timing in vertical RPoptics low (standard) β∗ high lumi β∗ = 90 m

RPs used horizontal verticaltracking 3D pixel (10 µm) current Si strip (20 µm/RP)timing L-bar cherenkov (30 ps/module) diamond (100 ps/plane)

or ultrafast silicon or diamond

• priorities for 2016◦ glueball searches (2015 data)◦ odderon searches: TOTEM only, special run with be∗ = 2500 m◦ di-photon searches with “accelerated” CT-PPS: standard low β∗ runs– motivated by “the 750 GeV may-be-resonance“, start CT-PPS programmewith current detectors now


Outlook : CT-PPS plan for 2016

• motivation: di-photon excess at 750 GeV observed byATLAS and CMS◦ CT-PPS: can see exclusive and complete events• background suppressible even without timing detectors◦ large mass: low background from inelastic photon pair + pileup◦ strong correlation between proton pair (RP) and photon pair (CMS ECal)◦ nevertheless: install 2 RPs with 4 diamond planes (originally for vertical RPs)– can also be used for (coarse) tracking

• tracking: use current Si strip detectors in station 210m◦ functional at least for 10/fb, then replaceable with detectors from 220m◦ detector/beam shift: irradiation distributed

• CMS-TOTEM integration successfully ongoing◦ trigger, DAQ, offline SW, DQM, ...◦ DQM snapshot: from Monday, beam with 900bunches, RPs inserted in physics positions,RPs included in global CMS DAQ, data pro-cessed with CMSSW 8.1.X (next release)→

x (mm)16− 14− 12− 10− 8− 6− 4− 2−

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Entries 1742Mean x 10.26− Mean y 3.218− Std Dev x 2.402Std Dev y 2.396

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Entries 1742Mean x 10.26− Mean y 3.218− Std Dev x 2.402Std Dev y 2.396

track XY profile


Outlook : Odderon searches

• Odderon = (hypothetical) cross-odd partner of Pomeron• overview of past Odderon searches◦ comparison pp vs. anti-pp (dip): not applicable at LHC◦ spin analyses: not applicable at LHC◦ structures in dσ/dt: where Pomeron contribution small– high-|t|: disfavoured by 13 TeV measurements– low-|t|: shifts of ρ value⇒ within reach of TOTEM

• Coulomb-nuclear interference at√s = 13 TeV◦ needs special optics: β∗ = 2500 m◦ |t| = 6 · 10−4 GeV2 reachable◦ ∼ 1 week data-taking timeapproved in 2016

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0 0.002 0.004 0.006 0.008 0.01|t| (GeV2)

block [06]bourrely [03]dl [13]ferreira [14]godizov [14]islam (hp) [06,09]islam (lxg) [06,09]jenkovszky [11]petrov (3p) [02]

√s = 13 TeV


Summary

• performance in Run II◦ all detectors functional◦ RPs equipped with RF shields⇒ less impedance⇒ close approach possible◦ DAQ throughput increased 50× wrt. Run I

• 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 or Cherenkov)

• priorities for 2016◦ glueball analysis of 2015 data◦ TOTEM special run: β∗ = 2500 m⇒ Odderon searches via CNI◦ CT-PPS runs with LHC standard optics: di-photon searches with existing RPs,...


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jan kašpar onbehalfofthetotemcollaboration

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