1. Hadron Calorimetry and Very-Forward Calorimetry in CMS Hadron Calorimetry and Very-Forward Calorimetry in CMS IPM09: 1st IPM Meeting On LHC Physics, 20-24 Apr 2009, Isfahan Mithat KAYA Kafkas University, Kars/Turkey ()‏ (member through Bogazici University)‏ On behalf of HCAL collaboration

2. Physics Objectives of Hadron Calorimetry Construction and overview of HCAL and Very- Forward Calorimetry(HB, HE, HO, HF, CASTOR and ZDC). Some Samples from Test Beam and Cosmic data. Mithat KAYA IPM09: 1st IPM Meeting On LHC Physics, 20-24 Apr 2009, Isfahan 2 Outlines

3. Had Barrel: HB Had Endcaps: HE Had Forward: HF Had Outer: HO Mithat KAYA IPM09: 1st IPM Meeting On LHC Physics, 20-24 Apr 2009, Isfahan 3 CASTOR Collarshielding (5.32 <  < 6.86)‏ ZDC (z =  140 m)‏ Beams EM HAD ECAL Scintillating PbWO4 crystals ECAL Scintillating PbWO4 crystals HCAL Plastic scintillator/brass sandwich HCAL Plastic scintillator/brass sandwich HF Quartz fibers/iron HF Quartz fibers/iron Eta Coverage Hadronic Barrel: HB  barrel  Hadronic Endcaps: HE  (endcap)‏ Hadronic Forward: HF  (forward)‏ Hadronic Outer: HO  outer  CASTOR 5.32 <  < 6.86 Hcal Thickness: ~ 5.5 @  =0 ~ 10.8 @  =1.3 ~ 11 in endcap ~ 10 @ 165 cm HF Hcal Thickness: ~ 5.5 @  =0 ~ 10.8 @  =1.3 ~ 11 in endcap ~ 10 @ 165 cm HF Hadron Calorimetry and Very-Forward Calorimetry

4. Mithat KAYA IPM09: 1st IPM Meeting On LHC Physics, 20-24 Apr 2009, Isfahan 4 Responsibilities of CMS Collaborators

5. HE: absorber manufacture, megatile production (optics) : Russia and Dubna Member States HO installation brackets & tooling, megatiles (including scintillator), optical cables & connectors: India HF absorber manufacture and installation tooling: Russia HF shielding, support structure: CERN, Russia, Turkey, Iran HF quartz fiber installation: Hungary HB/HE/HF: HV Supply Engineering: Bulgaria HB: absorber, megatile production (optics), optical cables & connectors, readout boxes, photodetectors (HPD’s), front end electronics, trigger/DAQ electronics, power supplies, controls: US CMS HE brass (75%) & scintillator acquisition (only): US CMS HE optical cables (materials) & connectors, readout boxes, photodetectors (HPD’s), front end electronics, trigger/DAQ electronics, power supplies, controls: US CMS HO readout boxes, photodetectors, front end electronics, trigger/DAQ electronics, power supplies, controls: US CMS HF and HF shielding mechanical design: US CMS HF quartz fiber (Plastic cladding): US CMS HF readout boxes, photomultipliers, front end electronics, trigger/DAQ electronics, power supplies, controls: US CMS Mithat KAYA IPM09: 1st IPM Meeting On LHC Physics, 20-24 Apr 2009, Isfahan 5 Responsibilities of HCAL Collaborators Andris Skuja Lv.2 HCAL Project Manager’s Overview US CMS Annual Meeting Riverside, California May 19, 2001

6. The Hadron Calorimeter plays an important role in the CMS detectors. Mainly to participate a Higgs boson measurement especially masses between 100 and 800 GeV. It plays an important role to discover new physics such as supersymmetry, darkmatter and so on….. Without the hardon calorimeter it is impossible to study Jet physics. It plays an also essential role in the identification and measurement of quarks, gluons, and neutrinos by measuring the energy and direction of jets and of missing transverse energy flow in the events. To Measure the Missing energy will help to understand the new physics such as superre of new particles, like the supersymmetric partners of quarks and gluons. Mithat KAYA IPM09: 1st IPM Meeting On LHC Physics, 20-24 Apr 2009, Isfahan 6 Physics objectives of Hadron Calorimetry

7. protonsneutronspions kaons The Hadron Calorimeter (HCAL) measures the energy of “hadrons”, particles made of quarks and gluons (for example protons, neutrons, pions, and kaons). neutrinos It provides indirect measurement of the presence of non-interacting, uncharged particles such as neutrinos. Higgs Boson Supersymmetric particles Measuring these particles can tell us if new particles such as the Higgs Boson or Supersymmetric particles have been formed. Mithat KAYA IPM09: 1st IPM Meeting On LHC Physics, 20-24 Apr 2009, Isfahan 7 Physics Objectives of Hadron Calorimetry

8. Mithat KAYA IPM09: 1st IPM Meeting On LHC Physics, 20-24 Apr 2009, Isfahan 8 Transverse slice through CMS detectors

9. The HCAL is organized into barrel (HB and HO), endcap (HE) and forward (HF) sections. It consists of 11 separate physical pieces 1.The positive and negative barrels : HB+ and HB-. 2.The positive and negative endcaps : HE+ and HE-. 3.The positive and negative forward calorimeters : HF+ and HF-. 4.The five rings of the outer HCAL : HO2-, HO1-, HO0, HO1+, and HO2+. Mithat KAYA IPM09: 1st IPM Meeting On LHC Physics, 20-24 Apr 2009, Isfahan 9 Construction of Hadron Calorimeter

10. 36 barrel “wedges”, each weighing 26 tones are located inside the magnetic coil. a few additional layers, the outer barrel (HO), sit outside the coil, ensuring no energy leaks out the back of the HB undetected. Similarly, 36 endcap wedges measure particle energies as they emerge through the ends of the solenoid magnet. The two hadronic forward calorimeters (HF) are positioned at either end of CMS, to pick up the myriad particles coming out of the collision region at shallow angles relative to the beam line. Mithat KAYA IPM09: 1st IPM Meeting On LHC Physics, 20-24 Apr 2009, Isfahan 10 Construction of Hadron Calorimeter

11. HCAL Readout system is dominated by mostly Hybrid Photodetectors and conventional phototubes. The light from scintillators is transported to the plastic fibers to the Hybrid Photodetectors (HPD’s) for HB, HE and HO. The response of HPDs is linear and they can operate in a high magnetic field, when the field is aligned with the applied electric field. HPDs have fiberoptic front window, conventional photocathode, pixelated diode (19 channels/device). The signals for HF are Cherenkov radiation in quartz fibers read by conventional phototubes. The essential electronics 2 elements are QIE’s(charge integrator and encoder), HTR’s (trigger and readout module) and event builder card (DCC- data concentrator card). Mithat KAYA IPM09: 1st IPM Meeting On LHC Physics, 20-24 Apr 2009, Isfahan 11 HCAL READOUT system

12. Mithat KAYA IPM09: 1st IPM Meeting On LHC Physics, 20-24 Apr 2009, Isfahan 12 HCAL Segmentation 5.0 3.0

13.  Sampling Calorimeter:Scintillator(active)&Brass(passive)‏  -1.3<<1.3  Two half barrels, each composed of 18 identical 20 degree wedges in Phi.  The wedges composed of flat brass alloy absorber plates parallel to the beam axis.  The innermost and outermost absorbers are made of stainless steel for structural strength.  17 active plastic scintillator tiles inserted between the steel and brass absorber plates.  The individual tiles of scintillator are machined to a size of ΔxΔ=0.087x0.087 and instrumented with a single wave length shifting fibers Mithat KAYA IPM09: 1st IPM Meeting On LHC Physics, 20-24 Apr 2009, Isfahan 13 Hadronic Barel for

14. The HB is divided into two half-barrel sections, each half-section being inserted from either end of the barrel cryostat of the super-conducting solenoid. The HB consists of 36 identical azimuthal wedges (Δ=20 0 ) which form two half-barrels (HB+ and HB–). Each wedge is segmented into four azimuthal angle (Δ=5 0 ) sectors. Mithat KAYA IPM09: 1st IPM Meeting On LHC Physics, 20-24 Apr 2009, Isfahan 14 Hadronic Barel March 2007

15. Since the barrel HCAL inside the coil is not sufficiently thick to contain all the energy of high energy showers, additional scintillation layers (HOB) are placed just outside the magnet coil. The full depth of the combined HB and HOB is app. 11. 1-cm thick Bicron BC408 scintillator tiles used. Each tile is read out with 4 wave-length shifting (WLS) fibers of 1.35 mm diameter, one in each quadrant of the tile. The WLS fibers are placed in groves which follow the boundary of each quadrant. Mithat KAYA IPM09: 1st IPM Meeting On LHC Physics, 20-24 Apr 2009, Isfahan 15 Hadronic Outer(HO)‏ An HO scintillator tile divided into quadrants, each with light collection a WLS optical fiber.

16. Mithat KAYA IPM09: 1st IPM Meeting On LHC Physics, 20-24 Apr 2009, Isfahan 16 The HO system is divided into six sections that follow the division of the barrel muon system. Ring 0 (+ and −) are in the central muon system and are composed of two layers of scintillators one immediately outside of the magnet cryostat and the other layer after a 15-cm thick iron layer. Ring 0 in the muon barrel system YB0 (the central part of CMS) covers the |η| range of 0 to 0.35. Rings +1, −1, +2 and −2 are single layer scintillators inserted in the muon barrel systems YB1 and YB2 on both positive and negative sides of CMS immediately inside the first muon iron layer covering the |η| range of 0.35 to 1.2. Scintillation light from the tiles is collected using multi-clad Y11 Kuraray wave-length shifting (WLS) fibres, of diameter 0.94 mm, and transported to the photo detectors located on the structure of the return yoke by splicing a multi-clad Kuraray clear fibre (also of 0.94 mm diameter) with the WLS fibre. Hadronic Outer(HO)‏

17. 18 wedges Mithat KAYA IPM09: 1st IPM Meeting On LHC Physics, 20-24 Apr 2009, Isfahan 17 The hadron calorimeter endcaps (HE) cover the rapidity range, 1.3 < |η| < 3 a region containing about 34% of the particles produced in the final state. The hadron calorimeter endcaps (HE) cover the rapidity range, 1.3 < |η| < 3 a region containing about 34% of the particles produced in the final state. HE is inserted into the ends of a 4T solenoidal magnet. C26000 cartridge brass(70% Cu and 30% Zn )non magnetic material used for the absorber Int. length~ 11 Weight: ~ 300 Ton HE is inserted into the ends of a 4T solenoidal magnet. C26000 cartridge brass(70% Cu and 30% Zn )non magnetic material used for the absorber Int. length~ 11 Weight: ~ 300 Ton Hadronic Endcap(HE)‏

18. Mithat KAYA IPM09: 1st IPM Meeting On LHC Physics, 20-24 Apr 2009, Isfahan 18 Total 20916 tiles 1368 Megatiles Total 20916 tiles 1368 Megatiles Hadronic Endcap Construction Light emission from the tiles is in the blue violet, with wavelength in the range λ = 410-425 nm. This light is absorbed by the wave-shifting fibers which fluoresce in the green at λ= 490 nm. The green, waveshifted light is conveyed via clear fiber waveguides to connectors at the ends of the megatiles. Light emission from the tiles is in the blue violet, with wavelength in the range λ = 410-425 nm. This light is absorbed by the wave-shifting fibers which fluoresce in the green at λ= 490 nm. The green, waveshifted light is conveyed via clear fiber waveguides to connectors at the ends of the megatiles. 79 mm 9 mm

19. Mithat KAYA IPM09: 1st IPM Meeting On LHC Physics, 20-24 Apr 2009, Isfahan 19 Megatiles are large sheets of plastic scintillator which are subdivided into component scintillator tiles, of size ∆η x ∆φ = 0.087 x 0.087 to provide for reconstruction of hadronic showers. Scintillation signals from the megatiles are detected using waveshifting fibers. The fiber diameter is just under 1 mm. HE η-φ illustration

20. HF covers a large pseudorapidity range, 3 ≤|η| ≤ 5, and thus significantly improve jet detection and the missing transverse energy resolution which are essential in top quark production studies, Standard Model Higgs, and all SUSY particle searches Higgs boson production through weak boson fusion as a potential Higgs discovery channel requires identification of high energy quark jets by the forward calorimeters. Mithat KAYA IPM09: 1st IPM Meeting On LHC Physics, 20-24 Apr 2009, Isfahan 20 Forward Hadron Calorimeter(HF )‏

21. The forward calorimeter (HF) is essential for Missing Energy determination as well as for tagging Higgs production HF is also an optical device, but a Cherenkov light device, sitting in a very high radiation environment. The Cherenkov light is produced and transmitted via quartz fibers to photomultipliers. The entire electronics and calibration chain for HF is similar/identical to that of HB. Mithat KAYA IPM09: 1st IPM Meeting On LHC Physics, 20-24 Apr 2009, Isfahan 21 Forward Hadron Calorimeter(HF )‏

22. HAD (143 cm)‏EM (165 cm)‏ 5mm Mithat KAYA IPM09: 1st IPM Meeting On LHC Physics, 20-24 Apr 2009, Isfahan 22  The HF calorimeter is based on steel absorber with embedded fused-silica-core and polymer hard-clad optical fibers  Fiber diameter 0.6 mm  Wire spacing 5 mm  Half a million of fiber will be read out by an about 2000 Phototubes(PMT)‏  The Front face is located at 11.2 m from the interaction point Light is generated by Cherenkov effect in quartz fibers Sensitive to relativistic charged particles (Compton electrons...)‏ Amount of collected light depends on the angle between the particle path and the fiber axis HF Construction TC (30 cm)‏ 5 mm thick grooved steel plates

23. Mithat KAYA IPM09: 1st IPM Meeting On LHC Physics, 20-24 Apr 2009, Isfahan 23 Wedge Fibers Source tube HF Fiber Insertion Half a million fiber inserted on to the 36 wedges ( 18 HF+ and 18 HF- )‏ Ferrules

24. Mithat KAYA IPM09: 1st IPM Meeting On LHC Physics, 20-24 Apr 2009, Isfahan 24 HF Tower Mapping large radius low eta (3.5-2.9) ieta= 29-32; High_Gain PMT medium radius mid eta (4.2-3.5) ieta= 33-36 Mid_Gain PMT small radius high eta (5.2-4.2)‏ ieta= 37-41 Low_Gain PMT HF divided in to a 4 quadrants iEta29 iEta30 ieta31 iEta32 iEta33 iEta34 iEta35 iEta36 iEta37 iEta38 iEta39 iEta40 iEta41 Physical Eta

25. Mithat KAYA IPM09: 1st IPM Meeting On LHC Physics, 20-24 Apr 2009, Isfahan 25 HF lowering Nov 2 2006 HF Construction

26. Mithat KAYA IPM09: 1st IPM Meeting On LHC Physics, 20-24 Apr 2009, Isfahan 26 HF Construction

27. Mithat KAYA IPM09: 1st IPM Meeting On LHC Physics, 20-24 Apr 2009, Isfahan 27 100 GeV electron Beam100 GeV Proton beam HF Simulated Showers

28. Magnetic field TEST 3 different test has been done Mithat KAYA IPM09: 1st IPM Meeting On LHC Physics, 20-24 Apr 2009, Isfahan 28 1.)Fringe Field at HF ROBoxes increases to 100 Gauss as expected 2.)LED test:Stability of LED(B)/LED(0) is app 1 PMT shielding is GOOD 3.)Raddam test: Stability of RADDAM(B)/RADDAM(0) (≈ 1) → RADDAM Fibers not damaged through B field ramp-up/down HF PMT's @ CRAFT and at 4 Tesla Kerem Cankocak Ferhat Ozok, Sercan Sen HCAL DPG Meeting 17 Nov. 2008 Magnetic field effect On HF

29. For the Normal pedestal runs we expect a signal just sitting on the pedestal region but sometime we are getting an unwanted signal besides pedestal. This signal can be one or more single photoelectron(spe).This is called Light Leak. For instance at the following figure it is clearly seen. Mithat KAYA IPM09: 1st IPM Meeting On LHC Physics, 20-24 Apr 2009, Isfahan 29 Pedestal Light Leak HF Light Leak Study This Light Leaks are disappeared After closed the HF

30. Mithat KAYA IPM09: 1st IPM Meeting On LHC Physics, 20-24 Apr 2009, Isfahan 30 Not a clear indication of a possible Light leak HF Light Leak Study @Craft

31. Mithat KAYA IPM09: 1st IPM Meeting On LHC Physics, 20-24 Apr 2009, Isfahan 31 From interaction point magnetic field in CASTOR measured to be 0.1T - 0.16T CASTOR effort: mesh type PMT’s (R5505/R7494 of Hamamatsu)‏ radius: 3.7cm to 14cm around beam pipe, 1.5m long ( 10 λ I )‏ magnetic field in CASTOR measured to be 0.1T - 0.16T CASTOR effort: mesh type PMT’s (R5505/R7494 of Hamamatsu)‏ radius: 3.7cm to 14cm around beam pipe, 1.5m long ( 10 λ I )‏ sampling calorimeter with tungsten and quartz coverage of pseudo-rapidity: 5.2 < η < 6.6 Cherenkov light read out by PMT’s electronic chain handles pulses for every bunch crossing sampling calorimeter with tungsten and quartz coverage of pseudo-rapidity: 5.2 < η < 6.6 Cherenkov light read out by PMT’s electronic chain handles pulses for every bunch crossing more details on:CMS-Note 2008/022 Very Forward Calorimetry CASTOR (Centauro And STrange Object Research)‏ CASTOR has 14 azimuthal sectors (semi-octants) which are mechanically organized in two half calorimeters

32. Mithat KAYA IPM09: 1st IPM Meeting On LHC Physics, 20-24 Apr 2009, Isfahan 32 CASTOR Design (a)Quarts plates of 4 mm thickness (b) tungsten plate (c) air-core light guides of the CASTOR prototype. In a heavy ion collisions Search for the exotic particles In a heavy ion collisions Search for the exotic particles The calorimeter is located behind the hadronic forward calorimeter The detector will contribute mainly to forward QCD studies (diffractive, low-x) and cosmic-rays-related physics in both proton-proton and heavy-ion collisions at LHC energies. More details in:CMS NOTE-2008/022

33. Mithat KAYA IPM09: 1st IPM Meeting On LHC Physics, 20-24 Apr 2009, Isfahan 33 Zero Degree Calorimetry (ZDC)‏ Beam pipe splits ~140 m from IR Beams EM Quartz fiber/tungsten plates Improves resolution at large b Readout through HF electronics signals available for L1 trigger Neutral particle absorber (TAN)‏ The detector slot will house the pp machine Luminosity Monitor (LM). It will have a length of 10cm and will need to have an absorber in front of it. This absorber will be the Electromagnetic Section (EM) of the ZDC with length of 10cm. The ~75cm behind the luminosity monitor will be used for the Hadron Section of ZDC (HAD)‏ HAD

34. Mithat KAYA IPM09: 1st IPM Meeting On LHC Physics, 20-24 Apr 2009, Isfahan 34 ZDC Construction Structure of Quartz/Quartz fiber: 0.6 mm – diameter of core; 0.63 mm – diameter of doped silica clad; 0.05 mm - thickness of polyamide buffer

35. Mithat KAYA IPM09: 1st IPM Meeting On LHC Physics, 20-24 Apr 2009, Isfahan 35 What can CMS do with ZDC

36. Some Results From the Test Beam and cosmic data Mithat KAYA IPM09: 1st IPM Meeting On LHC Physics, 20-24 Apr 2009, Isfahan 36

37. Mithat KAYA37 Muon signal at the HB from the HCAL and ECAL combined Test Beam-2006 The HB signal distribution for 150 GeV/c μ− from tower 4 (η = 0.3). The solid curve represents a fit using combined Gaussian and Landau distributions Using the 50 GeV/c electron calibration, the mean energy deposited by a 150 GeV/c muon is 2.4 ± 0.1 GeV. If the pion calibration correction is applied, the mean energy deposited is at 2.8 ± 0.2 GeV. IPM09: 1st IPM Meeting On LHC Physics, 20-24 Apr 2009, Isfahan the response of 150 GeV/c muons in the HB using 3 × 3 HB tower structure.

38. Mithat KAYA IPM09: 1st IPM Meeting On LHC Physics, 20-24 Apr 2009, Isfahan 38 Ratio of calibration constant for ring 1 HO tiles in the test beam set up with the HPD’s being operated at 10 kV and at 8 kV. Energy resolution for pions as a function of beam energy measured with EB + HB and with EB + HB + HO for the beam being shot at (a) η = 0.22 and (b) η = 0.56 Energy distribution for a 300 GeV pion beam measured with EB + HB and with EB + HB + HO. Pedestal peak and muon signal for a ring 2 tile operated with a voltage of (a) 8 kV, (b) 10 kV on the HO HPD. Design, performance, and calibration of the CMS hadron-outer calorimeterVolume 57, Number 3 / October, 2008 653-663 Springer Berlin / HeidelbergVolume 57, Number 3 / October, 2008 HO Test Beam Results

39. Mithat KAYA IPM09: 1st IPM Meeting On LHC Physics, 20-24 Apr 2009, Isfahan 39 Energy distribution for 150 GeV muons where all HE layers in a single tower are summed. Mean=3.53 GeV A/√E ⊕ B where E is in GeV, with stochastic term A = 1.02 GeV1/2 and constant term B = 0.027 300 GeV/c Pion Beam Fractional energy resolution of HE as a function of beam energy. HE Test Beam Results

40. Mithat KAYA IPM09: 1st IPM Meeting On LHC Physics, 20-24 Apr 2009, Isfahan 40 One of the unique features of the HF response is its speed. The peak position of pulses from 100 GeV electrons is ∼ 1 ns later compared to that of pions at the same energy. The average distance between electromagnetic and hadronic shower maxima is ∼ 17 cm. The deeper shower signals do reach the PMTs earlier because of the fact that the generated light travels shorter (fiber) distance. The di ff erence between the electromagnetic (t EM max ≈ 15 cm) and the hadronic (t HAD max ≈ 32 cm) shower maxima is about 17 cm, which corresponds to ∼ 1 ns time di ff erence between the arrivals of electron and pion signals to the PMTs HF Performance 2004 Test Beam Results More Details in: CMS NOTE 2006/044

41. Mithat KAYA IPM09: 1st IPM Meeting On LHC Physics, 20-24 Apr 2009, Isfahan 41 (a)High energy muons impacting the PMT glass generate spuriously large energies. (b) The zero-supressed energy loss distribution clearly shows the single p.e. peak at 4 GeV, as expected. 150 GeV Muon signal at HF 2004 Test Beam Results More Details in: CMS NOTE 2006/044

42. Mithat KAYA IPM09: 1st IPM Meeting On LHC Physics, 20-24 Apr 2009, Isfahan 42 CASTOR Aug-Sep 2007 Test Beam Results

43. Mithat KAYA IPM09: 1st IPM Meeting On LHC Physics, 20-24 Apr 2009, Isfahan 43 Shower profile for 80 GeV (a) electrons and (b) pions Energy resolution for (a)electrons and (b) pions Energy resolution More Details on:CMS CR -2008/090 CASTOR Test Beam Results Position Sensitivity The energy resolution is around 6% and 20% for 100 GeV electrons and pions respectively

44. Mithat KAYA IPM09: 1st IPM Meeting On LHC Physics, 20-24 Apr 2009, Isfahan 44 HCAL ENERGY ECAL ENERGY HO Energy HB ENERGY HF ENERGY Beam Direction 2.10 9 Proton Beam (clockwise) “shots” onto a collimator 150 meters upstream of CMS (also called “splash” events)‏ Hadronic Barel(HB)‏ First Event sept-2008 Collimator Closed

45. Mithat KAYA IPM09: 1st IPM Meeting On LHC Physics, 20-24 Apr 2009, Isfahan 45 HCAL ECAL Tracker DT COSMIC Event Samples At Global Runs B=3.8 T CMS ran for 4 continuous weeks 24/7 and collected nearly 300M cosmic events with B=3.8T

46. The HCAL and Very-Forward calorimetry detector systems and some Test Beam results are described here, These detectors are the essential part of the CMS experiment, without these detectors it is impossible to study new physics. The construction and the structure of these detectors are the perfection of both technology and engineering. Mithat KAYA IPM09: 1st IPM Meeting On LHC Physics, 20-24 Apr 2009, Isfahan 46 Conclusion