1. Erez Etzion, Tel Aviv University
ATLAS Upgrade Program
E. Etzion,
RECFA meeting,
Tel Aviv
April 10th, 2014
Erez Etzion, Tel Aviv University

2. E. Etzion, RECFA meeting, Tel Aviv
LHC timeline
Here is the timeline for the LHC (written in black) and ATLAS (in blue).because of the increase of the luminosity, The ATLAS detector must be upgraded according the LHC upgrades.
The NSW project will take place in the Phase 1 upgrade, around 2018
April 10th, 2014
E. Etzion, RECFA meeting, Tel Aviv

3. ATLAS Muon Spectrometer
CSC
MDT
TGC
A z-y view of 1/4 of the ATLAS detector (0,0) is the interaction point.
The yellow box is the big wheel region and the blue box is the small wheel region . In yellow we have the Cathode Strip Chambers (CSC) , in blue the Monitored Drift Tube chambers (MDT) and in violet the Thin Gap Chamber (TGC). It is located approximately 7 m from the interaction point. It covers the angles with eta between 1.3 and 2.7
April 10th, 2014
E. Etzion, RECFA meeting, Tel Aviv

4. E. Etzion, RECFA meeting, Tel Aviv
Thin Gap Chambers
April 10th, 2014
E. Etzion, RECFA meeting, Tel Aviv

5. E. Etzion, RECFA meeting, Tel Aviv
Muon trigger
April 10th, 2014
E. Etzion, RECFA meeting, Tel Aviv

6. E. Etzion, RECFA meeting, Tel Aviv
Why upgrade ?
Performance of the muon tracking chambers will be degraded with the luminosity increase
Muon end caps trigger will have too high fake rate
Average luminosity : cm-2 s-1
luminosity : 1034 cm-2 s-1
Simulated hit rate (Hz/cm2)
Range tube rate
kHz
On the left picture, we have the hit rate in the region of the Small wheel in the CSC and MDT chambers as function of the radial distance from the beam line for L = 9.6×1032 cm−2 s−1 at √s = 7 TeV
. The first 2 meters are covered by the CSC and the rest is covered by MDTs.in red, we have the fit to the data and in blue, the fit to the simulated cavern background (low energy photons and neutrons). The ration between the simulated and real data allows to calculate the foreseen rate at higher luminosity represented on the right picture : it shows the (observed) hit rates in the MDT and the CSC scaled to the value corresponding to the nominal Run III luminosity of 3 × 1034 cm−2 s−1.. We can clearly see that most of the detectors will be irradiate with a rate superior at 500 Hz/cm2
the yellow band represent the range of hit rate between 200 and 300 khz/tube, because of the size of the tubes. a big fraction of the MDT system will have to operate with tube rate much above 300 kHz. This is a real problem because as you can see on the next slide,
April 10th, 2014
E. Etzion, RECFA meeting, Tel Aviv

7. E. Etzion, RECFA meeting, Tel Aviv
NSW trigger concept
Increased Phase I backgrounds, but must maintain existing trigger rate
Filter “Big Wheel” muon candidates to remove tracks that are not from the IP Only track “A” should be a trigger candidate.
Challenge is latency: 500nsec for electronics + 500ns fibres to be in time for Big Wheel
Micromegas: 2M strips, 0.5mm
sTGC: 280K strips (3.2mm), 45K pads, 28K wires
sTGC, MM find candidates independently, list merged for Sector Logic
Hit per layer:
sTGC: hit is centroid of 3-5 strips
Micromegas: hit is address of strip  
April 10th, 2014
E. Etzion, RECFA meeting, Tel Aviv

8. E. Etzion, RECFA meeting, Tel Aviv
Detector layout
sTGCs: primary trigger detector
Bunch ID with good timing resolution – additional suppression of fakes
Good space resolution providing track vectors with < 1 mrad angular resolution
Based on proven TGC technology; Pads & strips, instead of only strips as in current detector
Micro-Mesh Gaseous detectors (Micromegas): primary precision tracker
Space resolution < 100 μm independent of track incidence angle
Good track separation due to small mm readout granularity (strips)
Excellent high rate capability due to small gas amplification region and small space charge effects
9.3m
A 3d view of the current small wheel. The CSC are in green , the TGC in brown and the MDT in blue. The size of the small wheel is roughly 10m high
Present Small Wheel – defines basic layout and envelopes
16 detector layers in total
2 technologies, MicroMegas and sTGC
April 10th, 2014
E. Etzion, RECFA meeting, Tel Aviv

9. E. Etzion, RECFA meeting, Tel Aviv
sTGC
Based on TGC technology
Lower cathode resistance – for high rates
Pads – online trigger tower
Strip charge readout – precision coord. readout
Wire readout – coarse f coord.
Pads coincidence defines ROI and select strips to send to sTGC trig processor where precise position is calculated
sTGC geometry
Wire-carbon gap
1.4 mm
Wire-wire space
1.8 mm
Strip pitch
3.2 mm
Inter strip gap
0.5 mm
Gas mixure
CO2:n-pentane (55:45)
Wire potential
2.9 kV
April 10th, 2014
E. Etzion, RECFA meeting, Tel Aviv

10. E. Etzion, RECFA meeting, Tel Aviv
Construction sites
April 10th, 2014
E. Etzion, RECFA meeting, Tel Aviv

11. E. Etzion, RECFA meeting, Tel Aviv
Muon test beam set up
Muon test beams at CERN (180 Gev)
Two quadruplets equipped with ASD, two monitor chambers (small TGC chambers M1 and M2) and two scintillators M1 M2
L1 L2 L3 L4
L5 L6 L7 L8
Sc1 Sc2
Combined test with sMDT
Mechanical system that allows to rotate the TGC with high accuracy
A typical test beam setup is composed of 2 scintillators read by PMTs to trig the signal. 2 monitors, which are in fact 2 small TGC are used to track the muons and the 2 quadruplets in between.
This set up allows to calculate efficiency, resolution,… and so on and …
April 10th, 2014
E. Etzion, RECFA meeting, Tel Aviv

12. Demonstrated homogeneity of the quadruplet Resolution < 100 mm
Position resolution
Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC), 2011 IEEE
Resolution : difference between expected position from track fit (3 planes) and measured position (4th plane)
Position resolution as a function of the incidence angle for the different layers of a sTGC
Measure the difference between the expected position from the track fit from 3 plans and measured in the 4th plans. We reached resolution between 60 and 110 um, depending on the HV applied and the position in the chamber.
On the bottom plot, the position resolution as a function of the incidence angle for the 4 layers of a TGC : we can see almost no effect of the incident angle and good homogeneity of the quadruplet.
Demonstrated homogeneity of the quadruplet Resolution < 100 mm
April 10th, 2014
E. Etzion, RECFA meeting, Tel Aviv

13. Irradiation with neutrons
Test in Demokritos (Greece) :
Cosmic muons tracking under neutron ( MeV) irradiation s
The TGC have been tested under neutron radiation at demokritos in greece. The setup is shown on the top figure :
the trigger for cosmic ray muons was provided by the triple coincidence of two pairs of ”monitors” – small TGC. The hit position was obtrained by the ”quadruplet” placed between the monitor pairs, as shown in the schematic. The same type of front-end and readout electronics as in the CERN test was used. The procedure of determining the efficiency and resolution was identical to the one described in the previous section, i.e. by fitting a track using three TGC layers and comparing the predicted and measured positions on the fourth
On the bottom figure, we can see the efficiency as a function of the irradiation rate. The efficiency deterioration at high rate is not significant. Although there was a concern that neutrons may give rise to large signals, producing sparks, no such sparks were observed during the five-day period of the test.
. A hit was considered good if the measured position was less than 10 mm away from the predicted one.
No drastic degradation of the efficiency : less than 4% at the highest dose rate
No sparks observed
Efficiency
rate for L=1035 cm-2s-1 90
April 10th, 2014
E. Etzion, RECFA meeting, Tel Aviv

14. Irradiation with 60Co source
Tests at Nahal Soreq (IL).
Cosmic muons detection under gamma (~50 Ci 60Co source) irradiation.
sTGC is 120x70cm2 was totally irradiated.
Position resolution and efficiency measurements with large scale Thin Gap Chambers for the super LHC,
arXiv: [physics.ins-det]
No efficiency deterioration observed for a flux of Hz/cm2
We keep the Same setup as for the neutron test.
The plot shows the efficiency as a function of the rate for different HV values. There is no efficiency loss even at high rate (~20kHz/cm2)
April 10th, 2014
E. Etzion, RECFA meeting, Tel Aviv

15. E. Etzion, RECFA meeting, Tel Aviv
nSW - Electronics
·         nSW Trigger Processor. A collaboration of Arizona, Brookhaven, Bucharest, Harvard, Saclay, UC Irvine, Weizmann. The Israeli team focuses on the sTGC part.
·        Front-end electronics ASIC. Testing and characterization of the FEE ASIC at Weizmann and Technion.
·         sTGC Front-end boards – collaborating with USTC on the requirements of the sTGC FE boards
·       New readout for Phase I and Phase II. A collaborative effort of Argonne, Brookhaven, CERN and Weizmann (initiators!) to develop common readout the shared across ATLAS. It is moves substantial functionality which was previously custom hardware for each detector to commercial PC servers and software.
·         nSW Electronics coordinator - L. Levinson (Weizmann)
April 10th, 2014
E. Etzion, RECFA meeting, Tel Aviv

16. New FE ASIC for the nSW : VMM
New ASIC common for MM and sTGC designed in Israel started testing in 2012
Front end provides
64 channels
Time to peak
Time over threshold
Adjustable gain : from 0.5 to 9 V/pC
Adjustable peaking time : from 25 to 200 ns
Threshold per channel
VMM1—An ASIC for Micropattern Detectors, G de Geronimo IEEE Trans.Nucl.Sci. 99 (2013) 1–8.
New ASIC common for MM and TGC delivered in 2012.
It provides :
64 channels
Time to peak
Time over threshold
Adjustable gain : from 0.5 to 9 mV/pC
Adjustable shaping time : from 25 to 200 ns
Threshold per channel
April 10th, 2014
E. Etzion, RECFA meeting, Tel Aviv

17. E. Etzion, RECFA meeting, Tel Aviv
Result sTGC strip + VMM1
In last test beam, strip readout was realized with ASD and VMM
ASD analog output (HV=2.85 kV)
VMM 3mV/fC (HV=2.85kV)
VMM 9mV/fC (HV=2.7kV)
Since a new front-end ASIC has been developed, it was important to test the position resolution that can be achieved with this electronics, in particular since the measurements are based on a peak sensing ADC and the efficiency.
Bottom figure shows the efficiency as a function of the impact angle for 3 configuration : ASD, VMM 3 mv/fc and 9 mv/fc.
The efficiency exceeds 92% for all relevant angles, while the lost 8% are mainly due to a minimum ionizing muon accompanied either by a δ-ray or a second particle
The top plot shows the postion resolution as a function of the impact angle for the 3 different configurations. It can be seen that the same position resolutions are achieved, but with a much higher efficiency.
VMM1 is working well . Some small problems will be corrected with the VMM2.
Except for a few minor problems, all VMM features are working
VMM2
April 10th, 2014
E. Etzion, RECFA meeting, Tel Aviv

18. E. Etzion, RECFA meeting, Tel Aviv
Simulation
Weizmann (S. Bressler) and Irvine U are working on L1 simulation looking at the PADs trigger
U. of Michigan and University of Science and Technology of China are working on the strip trigger side.
Technion (A. Di Mattia) responsible for the integration in Athena.
April 10th, 2014
E. Etzion, RECFA meeting, Tel Aviv

19. E. Etzion, RECFA meeting, Tel Aviv
Prototype status
60 x 40 quadruplets
Used to develop concept to construct sTGC
Training field for the new teams
Module -1
First development of full size sTGC
The type to be built in China
Parts are available and assembly underway
April 10th, 2014
E. Etzion, RECFA meeting, Tel Aviv

20. E. Etzion, RECFA meeting, Tel Aviv
April 10th, 2014
E. Etzion, RECFA meeting, Tel Aviv

21. E. Etzion, RECFA meeting, Tel Aviv
Status Israel
Israel provides overall project coordination
PL – G. Mikenberg
Construction at Weizmann inst.
Cosmic ray testing at Tel Aviv
Electronics developments at Weizmann and Technion
Test beam coordination Tel Aviv & Weizmann
Basic infrastructure well established
Focusing on development of assembly techniques
Knowledge transfer to Canada, Chile, China, US
Recently invested in producing a 40cm x 60cm quadruplet prototype
Developed drawings for full size modules
Production of prototype for the testbeam
April 10th, 2014
E. Etzion, RECFA meeting, Tel Aviv

22. E. Etzion, RECFA meeting, Tel Aviv
Man power
Instititue
Physicists
Engineers / Technicians
Post docs
Students
Technion
S. Tarem
N. Lupo
A. Vdovin
A. Di Mattia
Weizmann I.
G. Mikenberg
L. Levison
D. Lellouch
V. Smakhtin
S. Bressler
M. Shoa
B. Pasmantier
J. Narevicius,
Roich
8 technicians for instatation
Tel Aviv U.
Y. Benhammou
E. Etzion
M. Ben Moshe
M. Davies
A. Ashkenazi
H. Cohen
April 10th, 2014
E. Etzion, RECFA meeting, Tel Aviv

23. E. Etzion, RECFA meeting, Tel Aviv
Funding
Institute
Source
budget
Technion
I-Core equipment
ISF nSW
Aida (Gif++)
530 k$ *
1000 k$ (10 years)*
30 k euro (5 years)
Weizmann I.
ISF (IL-china)
+ for jigs
Minerva
360 k$
1000 k$ (10 years)
100 k$/year
100 k$
3 * 50 k euro
20 k$
Tel Aviv U.
206 k$
ISF nSW 3M$ paid to CERN in 10 years.
I-Core is an estimated extrapolation. Last two years we got ~30%
April 10th, 2014
E. Etzion, RECFA meeting, Tel Aviv

24. E. Etzion, RECFA meeting, Tel Aviv
Summary
nSW an approved international collaborative effort for the ATLAS upgrade
As in the ATLAS construction days a common Israeli effort !
Supported by ISF / institutes and iCORE.
nSW goal is to support high flux radiation without loss of trigger efficiency and position resolution
Sandwich with micromegas : MM for tracking purpose and sTGC for trigger (fully redundant)
First prototype of a new front end designed for MM and sTGC gave good results
Module-1 will go for testbeam at Fermilab on May 2014
MUON & nSW week in Israel on June.
Working toward installation on 2018.
April 10th, 2014
E. Etzion, RECFA meeting, Tel Aviv