“HERA and the LHC” Workshop 2006-2008 WG3 – Heavy Quarks Summary
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Transcript of “HERA and the LHC” Workshop 2006-2008 WG3 – Heavy Quarks Summary
HERA-LHC Workshop, CERN, 30.05.2008 WG3 - Heavy Quarks 1
“HERA and the LHC” Workshop 2006-2008
WG3 – Heavy Quarks Summary
WG3 Conveners:M.Cacciari, A.Dainese, A.Geiser, H.Spiesberger
HERA-LHC Workshop, CERN, 30.05.2008 WG3 - Heavy Quarks 2
HERA resultson charm and beauty
HERA-LHC Workshop, CERN, 30.05.2008 WG3 - Heavy Quarks 3
Beauty in photoproduction
HERA/LHC 2005:
HERA-LHC Workshop, CERN, 30.05.2008 WG3 - Heavy Quarks 4
Beauty in photoproduction
S.Boutle
reasonableagreementwith NLO QCDpredictions
theory appropriate for LHC many HERA II results still to come
2008:
HERA-LHC Workshop, CERN, 30.05.2008 WG3 - Heavy Quarks 5
Charm production at HERA A. Jung
full HERA II statistics2008:
HERA-LHC Workshop, CERN, 30.05.2008 WG3 - Heavy Quarks 6
Azimuthal correlations & MC@NLO
direct resolved enriched enriched
NLO
norm. OKshape X
MC@NLO for HERAnow almost ready!
needNNLOor
NLO+PS(MC@NLO)
data:
charm+ dijet
(jj)T.Toll
2005:
2008:
HERA-LHC Workshop, CERN, 30.05.2008 WG3 - Heavy Quarks 7
HERA-LHC Workshop, CERN, 30.05.2008 WG3 - Heavy Quarks 8
Heavy quarks in F2
HERA-LHC Workshop, CERN, 30.05.2008 WG3 - Heavy Quarks 9
beauty contribution to F2
HERA LHC, e.g. H, Z
Q2 >> mb2
2005:
HERA-LHC Workshop, CERN, 30.05.2008 WG3 - Heavy Quarks 10
P. Roloff
2008:
~10 x more to come
beauty contribution to F2
HERA-LHC Workshop, CERN, 30.05.2008 WG3 - Heavy Quarks 11
Charm contribution to F2
combination efforts ongoing
understand mass effectsfrom beauty
-> improved theory
-> validate gluon PDF´s for LHC
2008:
HERA-LHC Workshop, CERN, 30.05.2008 WG3 - Heavy Quarks 12
Heavy quark-related news in M(R)ST(W) PDF sets
New prescription – ACOT() – for coefficients functions at the thresholds New preferred values for the charm (1.4 GeV) and bottom (4.75 GeV) masses, obtained from detailed 2 analyses Study of intrinsic heavy quarks
up to 0.3% intrinsic charm allowed by EMC data on F2
c
R. Thorne
HERA-LHC Workshop, CERN, 30.05.2008 WG3 - Heavy Quarks 13
R. Thorne
HERA-LHC Workshop, CERN, 30.05.2008 WG3 - Heavy Quarks 14
R. Thorne
HERA-LHC Workshop, CERN, 30.05.2008 WG3 - Heavy Quarks 15
Towards 3-loop (s3) F2
c
I. Bierenbaum
HERA-LHC Workshop, CERN, 30.05.2008 WG3 - Heavy Quarks 16
I. BierenbaumTowards 3-loop (s
3) F2c
HERA-LHC Workshop, CERN, 30.05.2008 WG3 - Heavy Quarks 17
A look to the near future:perspectives at LHC
HERA-LHC Workshop, CERN, 30.05.2008 WG3 - Heavy Quarks 18
LHC: heavy quarks factory
Cross sections: NLO (MNR)
mc=1.2 GeV, F=R=2mc; mb=4.75 GeV, F=R=mb
Yields: assuming ppinel = 70 (40) mb
at 14 (0.9) TeV
LHC startup at 10 TeV:cross sections smaller by 20% w.r.t. 14 TeV
HERA-LHC Workshop, CERN, 30.05.2008 WG3 - Heavy Quarks 19
Updated benchmark cross sections
from HERA-LHC 04/05 Proceedings
Update for b at 14 TeV (MC@NLO by R. Guernane):
charm, pp 14 TeV
NEW
HERA-LHC Workshop, CERN, 30.05.2008 WG3 - Heavy Quarks 20
H. Spiesberger
accessible with HQ at HERA
need to measure c and b down to low pt!!
HERA-LHC Workshop, CERN, 30.05.2008 WG3 - Heavy Quarks 21
HERA-LHC Workshop, CERN, 30.05.2008 WG3 - Heavy Quarks 22
Acceptance for open heavy flavor at LHC
ALICE (c/b)
ATLAS/CMS (b) LHCb
(b)
-2 0 2 4 61
10
100
1 year pp 14 TeV @ nominal lumin.
pT o
f Q
-had
ron
[G
eV]
of Q-hadron
ALICE (b) (c)
important: complementarity of the 4 experiments
H1/ZEUS
HERA-LHC Workshop, CERN, 30.05.2008 WG3 - Heavy Quarks 23
CMS & ATLAS(A.Starodumov, V.Andreev, R.Wolf) (M.zur Nedden, J.Ginzburg, E.Lytken)
Muon detectionCalorimetrySilicon trackersAbout (only) 5% of trigger bandwidth for B Physics
HERA-LHC Workshop, CERN, 30.05.2008 WG3 - Heavy Quarks 24
CMS & ATLAS: B programmes
CP violation (e.g. B→J/ψ(X), B→)Bs oscillations (e.g. Bs→Dsπ, Bs→Dsa1)Rare decays (e.g. B→(X), B→K*γ)Inclusive cross section measurement
CMS
ATLAS
HERA-LHC Workshop, CERN, 30.05.2008 WG3 - Heavy Quarks 25
CMS & ATLAS: b production measurement
up to > 1 TeV/c!
CMS: b-jet tagging
bcJp
MLt
T
Jxy
)/(/
ATLAS: displaced J/ from B
+ several exlcusive channels
Channel N (100 pb-1)
B+ J/ K+ 17000
B0 J/ K0* 8700
Bs J/ 900
b J/ 260
HERA-LHC Workshop, CERN, 30.05.2008 WG3 - Heavy Quarks 26
LHC vs HERA: one heavy quark more (top!)
(> 2104 GeV2)
HERA-LHC Workshop, CERN, 30.05.2008 WG3 - Heavy Quarks 27
Theoretical developments in top production at LHC
HERA-LHC Workshop, CERN, 30.05.2008 WG3 - Heavy Quarks 28
HERA-LHC Workshop, CERN, 30.05.2008 WG3 - Heavy Quarks 29
LHCb(K.Harrison)
dedicated to B PhysicsCP violation
rare decays
B spectroscopy
many complementary channels
example: measurement of b cross sectioninclusive displaced muons
inclusive displaced J/ & D’s
exclusive B mesons
e.g. B+J/K+
HERA-LHC Workshop, CERN, 30.05.2008 WG3 - Heavy Quarks 30
ALICE (C.Bombonati, D.Stocco,R.Guernane,G.Bruno)
down to (almost) 0 pT!
Pb-Pb 5.5 TeVpp 14 TeVp-Pb 8.8 TeV
D0 K + B e + X
Charm Beauty
HERA-LHC Workshop, CERN, 30.05.2008 WG3 - Heavy Quarks 31
tot tot J/y bkgJ/y from B
CDF
pT>0
This measurement will be performed by all 4 LHC experiments
COMPARE
2<pT<3 Gev3<pT<5 GevpT>5 Gev
ALICE
displaced J/e-e+ALICE
HERA-LHC Workshop, CERN, 30.05.2008 WG3 - Heavy Quarks 32
Quarkonia production at LHCAmong first measurements + theoretical interest: What is the production mechanism?
The Color Octet Mechanism agrees well with measured shape from Tevatron Polarization measurements:CDF sees no sign of pol. for J/, and DØ (1S) measurements not consistent with predictions.
More data with high-pT needed!
Coloroctet
Color singlet
Tevatron data
NRQCD
(1s)
J/
kT factorization model
E. Lytken (ATLAS Collaboration) HERA-LHC workshop May 2008 9
Quarkonia Among first measurements
+ theoretical interest: What is the production
mechanism?
The Color Octet Mechanism agrees well with measured shape from TevatronPolarization measurements:CDF sees no sign of pol. for J/, and DØ (1S) measurements not consistent with predictions.
More data with high-pT needed!
Coloroctet
Color singlet
Tevatron data
NRQCD
(1s)
J/
kT factorizationmodel
HERA-LHC Workshop, CERN, 30.05.2008 WG3 - Heavy Quarks 33
E. Lytken (ATLAS Collaboration) HERA-LHC workshop May 2008 15
J/* = ATLAS~10 pb-1
* *** *
0.8 fb-1
Quarkonia PolarizationMainly based on muon triggers but in initial period will also have electron channels for comparisonAlready with 10 pb-1: measure J/ pol. to same precision as TeV with 1.3 fb-1 - but with interesting high pT data!Same precision for polarization studies can be reached after ~100 pb-1
Crude superimpose of ATLAS stat uncertainties with 10 pb-1 assuming =0 :
NRQCD
*
*
*
*
* = ATLAS~10 pb-1
*
measurement will be performedby all 4 experiments
HERA-LHC Workshop, CERN, 30.05.2008 WG3 - Heavy Quarks 34
Forward J/ production at ALICE
gg contribution dominant
normalized to 1
=> study shape only
sensitive to gluon PDFdown to x=10-6
HERA-LHC Workshop, CERN, 30.05.2008 WG3 - Heavy Quarks 35
Summary and ConclusionsHeavy Flavour production in ep and pp collisions is good testing ground for perturbative QCD
charm production: reasonably described, no clear preference
between "massive" NLO and "massless" NLL calculations.
NNLO or NLO+PS needed for some regions of phase space
MC@NLO now available for HERA; should be used for LHC
beauty production: reasonable description at high pTb -> OK for LHC
results seen at this workshop show agreement down to low pTb
Charm and beauty production at low pt at LHC: small-x effects?
saturation? to be measured by LHC experiments
DIS (F2): both charm and beauty well described first measurement of F2
bb understand mass effects, then extract b and gluon for LHC
J/production: LHC experiments have potential to clarify theory interpretation of picture emerging from Tevatron and HERA data
HERA-LHC Workshop, CERN, 30.05.2008 WG3 - Heavy Quarks 36
Thanks to:
WG3 speakersWG3 participants
the organizers