Status of ATLAS and LHC C Clement Stockholms

Status of ATLAS and LHC C. Clement (Stockholms Universitet) Partikeldagarna 2008, Stockholm

The Large Hadron Collider p-p collisions 14 Te. V Luminosity 1033 – 1034 cm-2 s-1

The Large Hadron Collider p-p collisions 14 Te. V Luminosity 1033 – 1034 cm-2 s-1 Process σ (nb) Min bias 108 bb 5· 105 Inclusive jets 100 p. T > 200 Ge. V W → eν, 15 Z → ee, 1. 5 tt 0. 8 Events ( Ldt = 100 pb-1) ~1013 ~1012 ~ 107 ~ 106 ~ 105 ~ 104

The Large Hadron Collider p-p collisions 14 Te. V Luminosity 1033 – 1034 cm-2 s-1 4 experiments to explore the constituents of matter and their interaction at 10 -19 m

The Large Hadron Collider p-p collisions 14 Te. V Luminosity 1033 – 1034 cm-2 s-1 Physics 4 experiments to explore the Motivations Higgs constituents of matter andboson Solve/ -19 m postpone Hierarchy Problem by their interaction at 10 Producing Dark Matter in the lab Susy, Kaluza Klein, little Higgs. . . ? Te. V scale gravity? Extra dimensions? Heavy gauge bosons? Quark and lepton compositeness? ? ? Quark – gluon plasma Flavour physics New sources of CP violation? Why 3 quark and lepton families? Precision b- and top physics. . .

The Large Hadron Collider p-p collisions 14 Te. V Luminosity 1033 – 1034 cm-2 s-1 4 experiments to explore the constituents of matter and their interaction at 10 -19 m Thousands of superconducting magnets in the 27 km ring. First beams to go around the ring on September 10, 2008 Eagerly awaited. . .

ATLAS Control room on September 10

ATLAS Control room on September 10 What 's on the TV screen?

First Beam to ATLAS / Sept. 10 tertiary collimators 140 m BPTX 175 m Target on purpose the collimators in front of the inner triplets (Low internsity beam)

First Beam to ATLAS / Sept. 10 tertiary collimators 140 m BPTX 175 m Target on purpose the collimators in front of the inner triplets (Low internsity beam)

Collimator events. . . tertiary collimators 140 m BPTX 175 m Target on purpose the collimators in front of the inner triplets (Low internsity beam)

First Beam to ATLAS / Sept. 10

LHC first few days LHC first turn Beam Dump Sweep Detection of the first proton bunch to ATLAS Beam Pick Up 175 m upstream of ATLAS: 1 st trigger

Radio frequency capture on day 2 ATLAS Trigger rate vs time Achieved circulating beam for 20 mn Test of the optics, measurements of beam parameters. . .

LHC first few days. . . “Pilot bunch” with 0. 56× 10 10 protons Cryogenic problems, no beam Polarity checks*, no beam through ATLAS Bunch intensity measurements at transfert line 2 and 8 Transformer failure in P 8, Sep 12, 23: 22

Incident on 19 th September Slide Stolen from Lyn Evans – LHC Project leader § During commissioning of the last main bend circuit to 5 Te. V an incident occurred resulting in the triggering of quench heaters of about 100 magnets and a large He discharge into the tunnel. § The most probable cause is a faulty electrical connection between two magnets. The sector is being brought to room temperature for repair. § The time needed for warmup, repair and cooldown precludes a restart before CERN’s obligatory winter shutdown. § The shutdown schedule is being modified to gain ~ 1 month of LHC operation in 2009. Lyn Evans – EDMS document no. 970483 16

What do we do now?

This ?

More like this. . .

ATLAS . . . is a complicated experiment Lots of things to fix, test, synchronize, calibrate, align. . .

ATLAS Inner Detector (ID) Purpose Charged particle tracks Photon conversions Momentum measurements Primary vertex identification Jet flavour-tagging. . .

Status of ATLAS Tracking LHC Collimator Event, ATLAS Pixel Off

Transition Radiation Tracker >90% in operation with final gas (Xe) Most of the remaining 10% will be addressed in winter shutdown Currently performing calibration, alignment and synchronisation Transition Radiation Probability Real cosmic event with B-field

Semi Conductor Tracker Large fraction of modues operated: Barrel: >99% EC*: >97% modules Large fraction of missing ones should be recovered during work on ID cooling in shutdown. Starting to look at actual alignment Φ SCT Hit Map Firsts tracks seen with hits in pixels and SCT combined z

Cluster Width Pixel >92 -95% in operation Continue commissioning, calibration, fine tune thresholds, mask noisy pixels. . . During shutdown i) Improve ID cooling, ii) Lower fraction which is not read out iii) Cosmics, calibration, alignment iv) Development for increased data taking flexibility Already accumulated more than 100 000 pixel tracks taken with and w/o B-field for alignment Track angle

ATLAS Calorimeters LArg: 99. 1% read out Fully electronically calibrated 6% of channels with HV < nominal requires corrections Stability of calibration <0. 2% Well known map of problems Address remaining problems during shutdown. Tile Calorimeter: currently 98. 6% usable for physics Address remaining problems during shutdown Cesium source calibration: adjust PMT HV for uniform response, Residuals <1% stored in DB. 0. 2% of channels cannot be calibrated All calibration constants in DB before 1 st beam

LHC events in ATLAS Calorimeters / Tile. Cal p attenuated through ATLAS beam EBC Barrel EBA µ Uniformity of response 1% per 'partition' and 6% b/w H-calos d. E/dx consistent with cosmics p End Cap Toroid Magnet Energy per Tile cell for events with E>1500 Te. V Azimuth Φ

LArg Calorimeters Forward Calorimeters FCal 3 C FCal 2 C FCal. A FCal. C Beam 2 3 2 FCal 1 A 1 1 2 3 ECC Population of channels (ADC>1300) consistent with direction of beam 2. Low relative population of FCal 2/3 channels on the A side. Beam Barrel ECA

L 1 Calo Trigger x 25 ns Uniformity of trigger timing before TOF correction During Shutdown: work on noisy towers, threshold adjustment large campain of timing equalisation energy calibration Calorimeter Tower >99% operation without error Critical timing and energy calibration Calorimeter Precision Read out

ATLAS Muon Precision Chambers Precision chambers MDT (Drift Tubes) MDT 99. 8% in read out (98. 5% with HV) Shutdown: aim at 99. 8% for physics Muon Calibration Data Stream in parallele physics runs t 0 constants calculation cycle 24 h Forward Precision Chambers CSC < 0. 1% dead channels Not yet part of ATLAS regular data taking, problem with off detector read out Address during shutdown Alignment ~99% of optical alignment sensors operational Some sectors aligned to ~50μm already Cosmic data taking for alignment in progress 10% p. T resolution for 1 Te. V requires 30μm precision on chamber positions

Noise problem ATLAS Muon Trigger Missing HV some electronic Fully operational, used daily <0. 1 % channels unvailable Barrel Muon Trigger: Resistive Plate Chambers Forward Muon Trigger Wheels: Thin Gap Chambers (TGC) Main Issues Reach trigger timing uniformity <25 ns before beam Large system difficult Alignment and repair of remaining small h/w problems Precision timing with collisions (<1 ns) will require several days of data at 1031 cm-2 s-1

Forward Detectors ALFA at 240 m ZDC at 140 m LUCID at 17 m LUCID: luminosity measurement Activity in LUCID during beam time Side C Side A Beam Condition Monitors during beam time

Conclusion & Outlook ATLAS in good shape for the first beam All h/w essentially operated and read out S/w and High Level Trigger operational Many sub-systems calibrated, and lots of runing experience Learned a lot from Collimator events and Few days of single beam data LHC incident on Sept 19 Extremely frustrating Beam back in the spring of 2009 What now for ATLAS? Timing, Calibration and Alignment campain ongoing with cosmics Fix small problems on the detector Continue to improve calibration, reconstruction s/w, Exercise software based Trigger algorithms

Beam Halo Muon in Muon Precision chambers

Beam Halo Muon in Hadron Calorimeter

Beam Halo Muon in the forward muon system