Calorimeter Outline: Detector status Calibration Upgrade Yu. Guz, IHEP, Protvino

Detector status

SPD – nothing required PS replace one (MAPMT+VFE) module ECAL replace all old type LEDs to new ones fix few dead/unstable PMTs and LED driver adjust LED flash magnitudes and delays after the replacement HCAL replace degraded PMTs (~100) fix few malfunctioning PMTs and LED driver ECAL, HCAL check ATI connectors at the inputs of FEBs The maintenance activities during YETS All the maintenance operations on the detector wall are done The detectors are closed

PS status Maintenance (feb 2016). Several dysfunctioning channels on PS2FEB18 (Middle region). The VFE board has been replaced. Checked with LEDs: OK. Recalibration of gains and HV ongoing with 2015 data. More news soon. Stephane Monteil

ECAL status All the 456 old type LEDs are replaced to new ones (CREE LC503) a good news: no dead LEDs since then the dead / unstable PMTs and LED drivers are fixed the LED control voltages are tuned to get reasonable amplitude of PMT signal the PIN diode amplitudes are adjusted accordingly (work on the LED boxes) the LED timing correction is done

HCAL status total of 104 PMTs replaced PMT dark currents after the replacement still many PMTs are expected to degrade in 2016 and beyond new PMTs to be purchased (under discussion)  the amount depends on our long-term plans for HCAL  minimum is 500

since 27-Jan, the LED data were permanently taken for ECAL and HCAL, to spot dead / unstable PMTs and LED drivers (the most usual reason of instabilities is loose contact in connectors). ECAL / HCAL – LED data taking

Calibration

SPD Vicente Jose Rives Molina April 2012October 2012 August 2015 (little recovery from Oct 2012 to Aug 2015)

SPD Vicente Jose Rives Molina New recipe intended to recover ~95% efficiency was applied on November 10. Verified on 5 TeV data (not large statistics, VFE-per-VFE efficiencies calculated). OK

PS The recalibration on 2015 data is ongoing same calibration scheme as in 2015 π 0 calibration every ~ 1 month LED following in between ECAL After the replacement of many PMTs, a 137 Cs calibration is needed scheduled for today will adopt same calibration scheme as in Run I and Cs calibration in Technical Stops LED following in between HCAL

ECAL: online π 0 calibration 08/07 05/09 06/10 19/11 A lot of work (Dasha, Roel, Silvia, online colleagues). The procedure is in place since π 0 calibrations in 2015, 08-Jul, 05-Sep, 06-Oct, 19-Nov in parallel, the work is ongoing on the procedure development Dasha

ECAL: π 0 calibration Still there is a room for improvement of the procedure there are significantly over- and under-calibrated cells in the ECAL centre obtained from comparison of raw occupancies in data (Oct 2015) and MC the correction will be applied in the HV recipe before the 2016 data taking, to help the calibration procedure capture the true π 0 peak Jean-François ECAL Inner, abs(ratio-1)>0.2

ECAL: π 0 calibration can it be improved by event selection, such that to enrich the calibration sample with photons (π 0 s) in the centre? e.g., low SPD multiplicity events. Studies are ongoing (Dasha) will need to organize a special HLT1 line a dedicated meeting will take place next Monday, March 14, From the fit parameters of the last iteration (provided by Dasha): problems may be related to lack of statistics in the centre bad fit of π 0 peak in ~100 cells (mainly central) Dasha

ECAL: π 0 mass Jean-François π 0 mass shift September - October online π 0 mass (from CaloRecMon savesets) Run (September) Run (October) offline π 0 mass (Philippe Ghez) The correction is applied in a new database: local tag calo included into a global tag cond

Upgrade

FEB status – I  the schematics is finished and checked  the PCB design is almost finished  the PCB manufacturer was contacted. Not yet decided whether we keep FR4 or go to Megtron6 or equivalent (we have 5 Gbit/s over 25 cm)  preliminary schedule for prototypes could be:  April: submission of PCB  May: submission of soldering the components  June: 2 prototypes first results before summer holidays beam test – autumn ?  new backplane power supply scheme Christophe

FEB status – II Christophe

FEB status – III Christophe

FEB: analog part Irradiation tests, several options  TID with X-ray:  CERN PH-ESE  Heavy Ion:  Louvain-la-Neuve  Seville (under investigation)  Neutrons  Is it needed?  Louvain-la-Neuve (dose too high)  Other options: Ljubljana Edu Setup preparation  Schematics: ready  PCB design: ongoing (1-2 weeks)  SW: once the PCB is in production (< 1 week) Test to be done as soon the boards are received and tested

HV, calibration and monitoring Anatoli control mezzanines a new version based on IGLOO2, to allow 1.5 V input (to match GBT-SCA) + improved functionality a prototype is ready under tests (with SPECS for the moment) GBT-SCA mezzanine to replace present SPECS mezzanines PCB design is under way GBT fanout board GBTx based, to control several GBT-SCA mezzanines via one optical link in functionality very much resembles the VLDB board designed by EP-ESE VLDB is going to be used for first tests, then custom boards will be designed

PMT linearity After upgrade, the PMT gain will be 5 times less than now problem with linearity can be expected, we should check Now: PMT gain at the ECAL centre is ~1000  200 after upgrade. The setup: two PMTs are illuminated by one LED. One of the PMTs is at gain~20k (assumed linear), another one is at low gain (under test). Amplitudes were ~ equalized with light filters DAQ: LeCroy ADC 1182 (50 fC/count). Result for gain=200: good linearity (<1%) till p T max=20 GeV (~640 ADC counts) Pavel

Dismantling during LS2 – I Present ECAL and HCAL electronics will have to be dismantled prior to install the upgraded electronics  Signal cables and connectors have to be well protected  Other cables running from the Patch Panel:  Some will not be need anymore o Optical fibres (2+1/CROC) o L0 trigger cables o PS/SPD cables  Some have to be kept o LV cables (MARATON) o DSS (CANbus for turbines) Pascal new cables (optical) will be installed in the cable chains Also, the cables between ECAL and HCAL will have to be dismantled. Good access is necessary: CALO position platform above muon filtres nacelles etc

Dismantling during LS2 – II Pascal  Electronics dismantling first  Cables: good access is important  Platform above RICH  Scaffoldings  PS passerelle  Do we have to dismantle M1 first?  Water cooling circuit  Cable trays  SM and lead dismantling  beam pipe has to be removed  radioactive waste?  Special tools will be needed o hanging tool o transport cradle o storage cradle? Current planning: 2 weeks per detector (SPD, Lead, PS  First experience will help adjust the timing!

Summary Detector  The YETS maintenance work is over  HCAL needs 137 Cs calibration (today)  Status of the online ECAL π 0 calibration will be discussed on Monday March 14 will be discussed on Monday Upgrade  FEB design is almost finished, two prototypes expected by June  irradiation tests of the analog part are planned for 2016  a good progress in the HV/Monitoring/Calibration  PMT linearity checked for low gain: OK up to p T max=20 GeV  LS2 dismantling planning is evolving  Not covered here: CALO Upgrade scenario for LS3 is under discussion A kickoff meeting January 20

Yu. Guz spares

Yu. Guz HCAL technical status – II >10 nA: 163 PMTs >50 nA: 59 PMTs >100 nA: 31 PMTs PMT degradation continues. ~100 PMTs would need replacement, depending on tolerance limit (of course for some of them the replacement can be postponed to the 2016/2017 EYETS). Purchasing of extra spare PMTs is under consideration. PMT degradation: dark currents I, nA

Yu. Guz HCAL technical status – III PMT degradation: rate effect ratio of LED amplitudes at the end and beginning of a long fill (4569) – a measure of rate effect. High positive rate effect accompanies high dark current. For normal PMTs (like in ECAL), rate effect is small, ~ +1…-2%

Yu. Guz HCAL technical status – IV PMT degradation: new PMTs installed do not degrade The 183 PMTs replaced in 2011 and 2014 are OK both in dark current and rate effect. I, nA

Yu. Guz HCAL PMT problem Found by HAMAMATSU experts: the vacuum inside the PMT bulb is not degraded, no micro cracks in glass the problems (dark current etc.) are caused by migration of alkali inside the bulb one PMT had been baked for 1.5 hour at 125 o C – the behavior improved significantly however the HAMAMATSU experts do not expect the improvement to be stable for long term From HAMAMATSU: light emission shows the place where dark current occurs While the way of degradation was found (migration of alkalis within PMT bulb), the reason why it happens in ECAL and not in ECAL is unclear. We can only make hypotheses. Note the fact that out of the new PMTs installed onto HCAL in none is degraded ny now

Yu. Guz HCAL technical status – IV : rate effect special fills (elastic and diffractive), low lumi (HV updates OFF) on average, rate effect is moderate. It depends on lumi in some cells the rate effect is high

Yu. Guz HCAL ageing Now the ageing continues at ~ same speed (not completely correct: in rad. dose, 1 pb TeV is equivalent to ~2 pb TeV) very fast ageing at startup TS1 TS2 29/08 TS3

Radiation damage of HCAL light yield beam PMT spacers WLS fibers light guide master plate scintillators row 0 row 1 row 2 row 3 row 4 row 5 The hadronic shower maximum lays within the tile row 0 (ECAL is ~1.2 λ I ); the dose in the row 5 is much less. No significant radiation damage to the LED system, PMTs, their Cockcroft-Walton boards, and integrators of the source calibration system, as all that is placed behind row #5. Longitudinal dose in HCAL, cell closest to the beam HCAL tile row As at 137 Cs calibration response of every individual tile is measured, the radiation damage of the HCAL light yield of scintillator tiles and fibers in a tile row #i can be determined as a decrease of relative response of this row, (A i /A 5 ), with respect to a reference 137 Cs run at lumi=0: Yu. Guz 33

Yu. Guz

ECAL calibration Except for EM triggers, ECAL participates in L0Hadron. ECAL stability is important. ECAL detector is based on the same components (scintillator light is being captured by WLS fibers and read out by PMTs) and subject to the same kind of ageing effects. ECAL is also equipped with LED calibration system. However it is suffering by itself from ageing effects (clear fibers transporting LED light to PMTs lose transparency because of radiation) and cannot be used to monitor the ECAL gains. A modification of the LED calibration system to make it rad hard is proposed for the LS1 (see next slides). May be important for the Upgrade (work at x10 lumi). -18% -4% Yu. Guz 35

Yu. Guz 2012 (plastic fibers) in 2015, with quartz fibers, the improvement is obvious (PMT/PIN) (PMT/PIN) pb (dose ~ equivalent to 27 pb (PMT/PIN) (PMT/PIN) pb TeV 2015 (quartz fibers)

ECAL: π 0 mass Jean-François π 0 mass shift September - October

ECAL: π 0 mass Jean-François π 0 mass shift September - October Run (September)

CALO DCS GBTX fan-out board with VLDB Optical Link E-Link HV-LED board GBT-SCA mezzanine control mezzanine Use existing DCS boards, replacing: SPECS mezzanine  GBT-SCA mezzanine control mezzanine  new one, based on Microsemi IGLOO2

HV, calibration and monitoring – II Anatoli LEDTSB – modules for LED firing timing and sequence  at present installed in the FE crates, control via SPECS bus at the backplane  at upgrade: will get e-links via front panel  -5V will be needed for module calibration. Can also be obtained from an external power supply when needed mini-HDMI (e-Link) +5V -5V