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Other experiments at LHC: LHCf, MoEDAL, Totem. Oscar Adriani Università degli Studi di Firenze INFN Sezione di Firenze. David(s) vs Goliath. But also David(s) are able to do very good physics!!!!. Nuclear Track Detector based experiment Detector is: Exposed Removed Off-line analyzed.
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Other experiments at LHC:LHCf, MoEDAL, Totem Oscar Adriani Università degli Studi di Firenze INFN Sezione di Firenze
David(s) vs Goliath But also David(s) are able to do very good physics!!!! Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
Nuclear Track Detector • based experiment • Detector is: • Exposed • Removed • Off-line analyzed Totem ‘Traditional style’ particle physics detector Online DAQ system Located in the forward/very forward region MoEDAL LHCf Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
LHCf & Totem Dedicated forward/very forward experiments Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
How to access Forward/Very Forward Region at LHC? Charged particles Neutral particles Beam pipe Surrounding the beam pipe far away from IP with detectors Simple way, but still miss very very forward particles Approach #1 used by Totem Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
Charged particles Neutral particles Beam pipe How to access Forward/Very Forward Region at LHC? Install detectors (movable!) inside the beam pipe very far away from the IP Challenging but ideal for charged particle Approach #2 used by Totem Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
How to access Forward/Very Forward Region at LHC? Charged particles Neutral particles Beam pipe Detectors can be installed where the single beam pipe splits In 2 separate beam pipes, 140 m away from the IP All neutral particle produced can be measured Approach used by LHCf (and in general by the others Zero Degree Calorimeters) Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
Pseudo rapidity coverage at LHC Pseudorapidity:h = - ln (tanq/2) Particle flow Energy flow All phase space covered thanks to dedicated forward detectors! And most of the energy is concentrated in the forward regions! Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
Totem Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
Totem experimental layout T1:3.1 < h < 4.7 T2: 5.3 <h< 6.5 T1 10.5m T2 CASTOR (CMS) 14m Roman Pot @147 m Roman Pot@220 m Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
T1 Telescope • Cathode Strip Chambers (CSC) • 3.1 < || < 4.7 • 5 planes with measurement of three coordinates per plane, ~ 1 mm • Primary vertex reconstruction (beam-gas interaction removal) • Trigger with anode wires • Both arms are completely assembled and equipped in the test beam line H8. • Successfully tested with pion and muon beams in May – June 2010 • Both telescope arms not yet installed but ready for installation ~3 m 1 arm chamber frames 0.8 1.1 m strip strip wire ¼ ofT1 Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
T2 Telescope • Gas Electron Multiplier (GEM) • 5.3 < || < 6.5 • 10 half-planes @ 13.5 m from IP5 • Half-plane: • 512 strips (width 80 µm, pitch of 400 µm), radial coordinate • 65*24=1560 pads (2x2 mm2 -> 7x7 mm2), radial and azimuth coord. • Resolution:(R) ~ 100 µm, () ~ 1° • Primary vertex reconstruction (beam-gas interaction removal) • Trigger using (super) pads • All T2 chambers on both sides of IP5 installed and operational (data & trigger) 40 cm strips pads Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
T2: Preliminary h Distribution (with detector efficiency) T2 h acceptance Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
Roman Pots • Measurement of very small proton scattering angles (few µrad) • Vertical and horizontal pots mounted as close as possible to the beam • BPM fixed to the structure gives precise position of the beam • All 12 Roman Pots at ±220 m from IP5 are operational (data with active triggers) • RP147 detector assemblies to be installed during next winter technical stop. Horizontal RP Vertical RP BPM HALF OF THE RP STATION Roman Pot 14 Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
Alignment is the central problem of Roman Pot measurements: Done at 450 GeV on the 25th of June 2010 LHC collimation system produces sharp beam edges: used to align Roman Pots and to determine the centre of the beam same procedure as collimator setup When both top and bottom pots “feel” the edge: they are at the same number of sigmas from the beam centre as the collimator the beam centre is exactly in the middle between top and bottom pot RP alignment w.r.t. the Beam Centre Collimator cuts a sharp beam edge symmetrically to the centre RP approaches this edge until it scrapes … … producing spike in BLM downstream The second RP approaches Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
Totem Physics plans Early physics plan (2010-2011) Physics at s 7 TeV with low * (= 2 - 5 m) optics: forward charge particles studies with T2 large |t| elastic scattering high mass SD & CD Physics at s 7 TeV with short * = 90 m runs: early measurement of tot @ 5-6 % elastic scattering in wider |t|range (|t| > 0.015 GeV2) SD & CD @ any M classification of inelastic events: inelastic rates process dependent forward charged multiplicity Full physics plan TOTEM TOTpp with a precision ~ 1-2% Elastic pp scattering in the range 10-3 < |t| ~ (p)2 < 10 GeV2 Soft diffraction (SD and DPE) Particle flow in the forward region (cosmic ray MC validation/tuning) TOTEM & CMS Soft and hard diffraction in SD and DPE (production of jets, bosons, h.f.) Central exclusive particle production Low-x physics Particle and energy flow in the forward region Total cross-section b Diffraction: soft and hard Elastic Scattering Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
p-p Total Cross Section T1&T2 RP Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
Elastic scattering, exponential part BSW b*=90m ∫Ldt= 0.3pb-1 exponential region 2x109 b* = 90 m 1.5x106 11m b* = 11 m b* = 2 m 4000 90m 500 30 1540m 1 0.3 High * optics needed to measure the total pp cross-section Early optics: b*=90m (un-squeezing of existing injection optics, |t|>3 102 GeV2) Target optics: b*=1540m (difficult to have at the beginning – requires special injection optics) acceptance at very low |t|> 2 103 GeV2 Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
LHCf Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
Experimental set-up Detector II Tungsten Scintillator Silicon mstrips Detector I Tungsten Scintillator Scintillating fibers INTERACTION POINT IP1 (ATLAS) Protons Charged particles Neutral particles 140 m 140 m Beam pipe Detectors installed in the TAN region, 140 m away from the Interaction Point 1 • Here the beam pipe splits in 2 separate tubes. • Charged particle are swept away by magnets • Coverage up to h Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
32mm 25mm The LHCf detectors Sampling and Position-measurement Calorimeters • W (44 r.l , 1.7λI ) and Scintillator x 16 Layers • 4 position measurement layers XY-SciFi(Arm1) and XY-Silicon strip(Arm#2) • Each detector has two calorimetric • towers, to allow the p0reconstruction Expected Performance Energy resolution (> 100GeV) < 5% for photons 30% for neutrons Position resolution < 200μm (Arm#1) ~40μm (Arm#2) Arm2 Front Counter • Thin scintillators 80x80mm2 to monitor beam condition. • For background rejection of beam-residual gas collisions by coincidence analysis 40mm Arm1 20mm Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
ATLAS & LHCf Goliath David Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
HECR Open Issues AGASA Systematics Total ±18% Hadr Model ~10% (Takeda et al., 2003) M Nagano New Journal of Physics 11 (2009) 065012 Difference in the energy scale between different experiments??? The depth of the maximum of the shower Xmax in the atmosphere depends on energy and type of the primary particle Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
Development of atmospheric showers Cosmic ray spectrum Tevatron LHC A 100 PeV fixed-target interaction with air has the cm energy of a pp collision at the LHC LHCf: use LHC √s = 14 TeVElab=1017eV to calibrate MCs AUGER Determination of E and mass of cosmic rays depends on description of primary UHE interaction Hadronic MC’s need tuning with data The dominant contribution to the energy flux is in the very forward region ( 0) In this forward region the highest energy available measurements of p0 cross section done by UA7 (E=1014eV, y= 5÷7) AlessiaTricomi University and INFN Catania Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
What LHCf can measure? • Energy spectra and transverse momentum distribution of • g (E>100GeV,DE/E<5%) • Neutral Hadrons (E> few 100 GeV, DE/E~30%) • p0 (E>700GeV, DE/E<3%) • in the pseudo-rapidity range h>8.4 γ π0 n Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
LHCf operation in 2009 & 2010 With Stable Beam at 450 +450 GeV 42 hours for physics ~100,000 showers events in Arm1&Arm2 With Stable Beam at 3.5+3.5 TeV 150 hours for physics with different setups Vertical position Beam crossing angle ~4.108 showers events in Arm1&Arm2 ~106p0 events in Arm1&Arm2 LHCf completed operation at 900GeV and 7TeV The detectors were removed from the LHC tunnel on 20/07/10 The detectors will be re-installed for operation at 7TeV+7TeV in 2013 after the upgrade of the detector for radiation improvement Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
Impressive TeV Shower Longitudinal projections X Transverse projection Y Transverse projection Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
Spectra at 900GeV Arm1 Hadron like Gamma-ray like preliminary preliminary Only statistical errors are shown Arm2 Hadron like Gamma-ray like preliminary preliminary Spectra are normalized by number of gamma-ray and hadron like events Detector response for hadrons and systematic errors (mainly absolute energy scale) are under study. Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
p0 reconstruction @ 7 TeV An example of p0event Measured p0 energy spectrum @ Arm2 preliminary Reconstructed mass @ Arm2 ΔM/M=2.3% p0’s are a main source of electromagnetic secondaries in high energy collisions. The mass peak is very useful to confirm the detector performances and to estimate the systematic error of energy scale. preliminary Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
h search p0Candidates h Candidates preliminary • h/p0ratio vary a lot among different interaction models. • A good handle to probe the hadron interaction models • Another calibration point for more robust energy scale Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
Moedal Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
Searching for Magnetic Monopoles From the experimental point of view: Very highly ionizing particle! Extended search up to now done both at accelerators and in CR MM energy loss Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
MoEDAL is located in the LHCb IP, covering the VELO cavern Plastic track edge detector based experiment • Operating procedure: • Expose the detector • Remove it • Chemical etching to create the etched cones • Scan the etched plates searching for aligned holes, pointing to the IP (Dx~1cm) mm mm mm MoEDAL: Monopole search at LHC: ppppMM 25 m2 in total A test detector is already installed The full MoEDAL will be installed in the next LHC shutdown Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
Drell-Yan cross-section for magnetic-monopole pair production at the LHC Physics Reach for MM Production Exclusion curve for 10fb-1 (e x acceptance=30%) Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
Conclusions • Interesting physics cases can be studied also with ‘David like’ detectors optimized for specific measurements • Totem: stot and Diffraction • LHCf: MC tuning for Cosmic Rays experiments • MoEDAL: Monopole search • Full support from Cern and LHCCThanks! • Nice physics results are already coming and more exciting ones will certainly come in the near future • P.S: Please note: David and Goliath are not ennemies, but nice friends!!!!! Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
Backup slides Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
LHCf : Monte Carlo discrimination @ <14 TeV γ γ n n Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
MC (QGSJET2) Data Preliminary Particle Identification A transition curve for Gamma-ray A transition curve for Hadron Thin for hadronic interaction(1.7l) Thick for E.M.interaction (44X0) Definitionof L90% L90% @ 20mm cal. of Arm1 Gamma-ray like Gamma-rays: L90%<16 r.l. + 0.002 x SdE Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
Radiation Damage Studies Scintillating fibers and scintillators • Expected dose: 100 Gy/day at 1030 cm-2s-1 • Fewmonths @ 1030 cm-2s-1: 10 kGy • 50% light output • Continous monitor and calibrationwith Laser system!!! 30 kGy 1 kGy The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 Alessia Tricomi University & INFN Catania Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
Roman Pot detectors Thin window 0.150mm 0.5mm Beam • Leading proton detection at distances down to 10×(beam) + d • Need “edgeless” detectors that are efficient up to the physical edge to minimize “d” • (beam) ≈ 0.10.6 mm (optics dep.) 10 planes of edgeless detectors Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
Si Edgeless Detectors for RP I1 I2 current terminating ring biasing ring Al - + SiO2 p+ p+ n-type bulk cut edge Al n+ 50µm 3.5 cm Planar technology with CTS (Current Terminating Structure) 66 μm pitch dead area 50 µm • AC coupled microstrips made in planar technology with novel guard-ring design and biasing scheme • Readout with VFAT chips • Leakage current : 60 nA at 200 V (excellent) • All produced • Installation ongoing: RP220 (147) fully (partially) equipped by June 28/04/2009 Hubert Niewiadomski, TOTEM Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
RP alignment @ 450 GeV Start with primary collimator at 4.9 s beam edge at 4.9 s RP 4-5 (-220m) Near – TOP @ 4.9s RP approach (in ≥100mm steps) Beam Loss Monitor (BLM) BLM @ 221 m BLM @ 225 m RP 4-5 (-220m) Near–BOTTOM @ -4.9s RP trigger rate Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
Top Top Horizontal Horizontal Bottom Bottom Near Far A Single Track Event in RP transverse view Top Hor. Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
T2 event @ 7TeV Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
LHC Optics Proton position at RP (x*, y*) is a function of position (x*, y*) and divergence (Qx*, Qy*) at IP: – momentum loss Beam size and beam divergence at IP5 and at RP spread of the primary vertex, beam size at RP beam divergence at IP5 limits the angle measurement precision Qx measured reconstructed • Proton acceptance is determined by • optical functions, mainly Lx, Ly, Dx • beam size sx, sy at RP • internal LHC apertures RP IP5 proton RP det. IP5 Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
Combined uncertainty in tot • * = 90 m 1540 m • Extrapolation of elastic cross-section to t = 0: ± 4 % ± 0.2 % • (Smearing effects due to beam divergence, • statistical errors, uncertainty of effective length Leff, • RP alignment, model dependent deviations) • Total elastic rate (strongly correlated with extrapolation):± 2 %± 0.1 % • Total inelastic rate: ± 1 % ± 0.8 % • (error dominated by Single Diffractive trigger losses) • Error contribution from (1+2): ± 1.2 % Total uncertainty in tot: ± 5% ± 1÷2% Total uncertainty in L : ± 7 % ± 2 % * = 90 m required for early tot measurement during the first year of LHC running at 7 TeV Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
Inelastic event rateNinel p p p T1&T2 + RP provide fully inclusive trigger: Primary vertex reconstruction to discriminateagainst beam-gas interactions TOTEM Trigger efficiency: SD: 82 %, NSD > 99 % Single Diffractive Trigger: Double Diffractive Trigger: Central Diffractive Trigger: Minimum Bias Trigger: RP CMS RP T1/T2 48 Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
TOTEM diffractive protons’ acceptance 5TeV, *= 3 m 7 TeV, *= 90 m 7 TeV, *= 1535 m Log(-) Log(-) Log(-) prelim. Log(-t/GeV2) Log(-t/GeV2) Log(-t/GeV2) low * low* : 0.5 – 2 m, L 1033 cm-2s-1 early running: E = 5TeV, * = 3 m elastic acceptance 2 GeV2 < -t < 10 GeV2 resolution () = 16 – 30 µrad () = 1 – 6 10-3 - > 2 % seen (hard) diffraction, high |t| elastic scattering * = 90 m L 1030 cm-2s-1 elastic acceptance 3 10-2 GeV2 < -ty < 10 GeV2 resolution () = 1.7 µrad () = 6 – 15 10-3 all seen, universal optics diffraction, mid |t| elastic scattering, total cross-section * = 1535 m L 1028 – 1029 cm-2s-1 elastic acceptance 2 10-3 GeV2 < -ty < 0.5 GeV2 resolution () = 0.3 µrad () = 2 – 10 10-3 all seen total cross-section, low |t| elastic scattering 28/04/2009 Hubert Niewiadomski, TOTEM Oscar Adriani Other experiments at LHC Toronto, August 27, 2010
Oscar Adriani Other experiments at LHC Toronto, August 27, 2010