Upgrade R&D January 2005 A. Seiden U.C. Santa Cruz

2 Physics F. Gianotti Int’l Workshop on Future Hadron Colliders, FNAL, Oct %-30% extension mass-scale reach

3 From Recent Talk by R. Aymar, CERN DG Scientific Objective (1) Complete LHC. Scientific Objective (2) Work with European laboratories on a number of accelerator projects. Scientific Objective (3) To develop detailed technical solutions for a future LHC luminosity upgrade to be commissioned Definition of the Linac4 (160 MeV-H-), in relation with the European Programme for a High Intensity Pulsed Proton Injector (HIPPI). Definition of modifications to the magnets in the interaction regions at two crossing points of the LHC beams, linked with the European programme Next European Dipole (NED), aiming at 15 Tesla. Definition of new trackers for the upgrade of the ATLAS and CMS detectors, to withstand a factor 10 higher luminosity.

4 R & D Schedule ATLAS will require a new tracking detector around To have the tracker ready in time will require a construction start around This leaves little time for R&D given that first priority must go to commissioning, integration, and calibration of present detector; followed by data taking and analysis. Will have to choose carefully R&D directions to deal with schedule and financial constraints. Coordination with partners in the international community will be very important.

5 Plan From Last Year (1) Understand better the interests of the U.S. participants. (2) Develop initial priorities. (3) Request modest amount of funding for high priority, long lead time, items. (4) Work with ATLAS collaborators on overall organization. (5) Try to get a simulation effort started to guide the global tracker design.

6 ATLAS Wide Steering Group IDGiovanni Darbo, Abe Seiden LArFrancesco Lanni TilesDominique Pallin MuonsSandro Palestrini, Tatsuo Kawamoto TDAQStefan Tapprogge (Chair of Steering Group) ECPhillipe Farthouat Shielding/RadiationVincent Hedberg TCnDavid Lissauer Machine LinkPer Grafstrom PhysicsGiacomo Polesello ATLAS management, ex-officio

7 Steering Group Activities Have had nine meetings since July Initial goal has been to interact with machine group to provide input from detectors on options for the beam structure, look at shielding issues, develop workplan document, and begin program. Will have a two day workshop at CERN on Feb. 13 and 14 on upgrades. Planning a several day workshop on the tracker upgrade in July in Genoa.

8 Tracker Agenda for Feb 13 and 14 meeting (1)Lessons Learned from Present ATLAS Detector – M. Gilchriese (2)First Simulation Results – P. Nevski (3)Options for Pixel Detectors – K. Einsweiler (4)Strips at Mid and Large Radii – A. Seiden (5)Optoelectronics – T. Weidberg (6)New Tracker Materials and RD 50 – M. Moll

9 Initial Simulation Results Have started Geant simulation, led by Pavel Nevski of BNL. Simulation had 230 minimum bias events per crossing. Detector had: 4 pixel layers, modules like present ATLAS, radii from 5 cm to 25 cm. 6 strip layers, 50 micron x 6 cm strips, about 3 times finer segmentation than present ATLAS strip detectors. Radii from 35 cm to 105 cm. Innermost pixel occupancy ½%. Innermost strip occupancy 1%. These numbers indicate that we know roughly what is needed and issues are primarily technical.

10 Technical Challenges for Tracking RadiusExpected FluenceComparison to Present DesignSome Special Challenges 7.5 cm10 16 /cm²New TerritoryCharge Trapping 25 cm10 15 /cm²Like PixelsLarge Depletion Voltages 75 cm10 14 /cm²Like SCTLarge Leakage Currents

11 Process for FY05 Funding General meeting on Upgrade R&D in January 2004 to outline issues. Followed by request for 1 to 2 page statements of interest from U.S. ATLAS groups. Received statements from 18 groups, with 13 relevant to the inner detector. Had Steiner Stapnes, ATLAS Inner Detector Coordinator, provide independent comments on the statements of interest. Worked with groups to define a program covering a number of key areas. They were given rough funding estimates for FY05 and asked to lay out a two year program in a fairly detailed (5 to 10 pages) document. Went through one iteration to arrive at a program for FY05 that matched funding guidance, which was about $.5M.

12 Upgrade R&D Program for FY05 Plan for U.S. ATLAS Upgrade R&D for FY05. The people working on these projects are all in good communication and a true overall collaboration is developing. The program elements, all representing unique work directed at the high luminosity environment of an upgraded ATLAS, are as follows: 1) Development of a stave readout structure. This is a collaboration of BNL, Hampton, and LBNL, with UCSC anticipated to join later. This work leverages past effort for CDF in developing stave structures that minimize material, cabling, and power connections. Improvements in these areas are essential to fit a new tracker with many more channels into the space available in the ATLAS detector. 2) Development of a stripixel detector with small angle stereo readout and other features required to survive high integrated luminosity. These detectors look like a very promising choice for radii between about 25 and 65 cm. This is a unique U.S. effort and leverages past work on these detectors at BNL. This work will be done at BNL, but the detectors developed will be integrated into the stave structure in (1) and will fit together with the work on detector materials in (3). 3) Evaluation of detector materials, new choices for electronics, and development of a short strip detector (alternative to the stripixel detector, but also likely choice for outer tracking elements). New commercial electronics technologies will be evaluated for use with high-capacitance load detectors such as short strip or stripixel detectors. This work, which will be done at UCSC, leverages the effort within the RD50 collaboration on materials based on collaborative work that has been established, and funding from the DOE ADR program. A goal is to eventually integrate a radiation hard detector into the stave structure and to provide input on materials to the stripixel effort. 4) Work on 3-D pixel detectors. These detectors provide one of a very small number of alternatives for detectors inside of a radius of about 15 cm. The detector concept originated in the U.S. and we can leverage work toward other applications, particularly in biology. This is a collaboration of the Univ. of Hawaii and the Univ. of New Mexico. They will provide detectors and evaluate their radiation properties after irradiation. The LBNL pixel group collaborates informally regarding readout issues. 5) Characterization of readout chips using 0.13 micron CMOS. This work is essential for detectors of the future as industry is shifting to smaller feature size. The detailed chip design, layout, and measurements will be done by LBNL. This group has already submitted a chip (last year) and the effort is based on several years of work developing the present ATLAS pixel chip.

13 FY05 Upgrade R&D Program We anticipate several additional projects related to tracking starting a year from now, in addition to work on other detector subsystems. The tracker related projects, are in the areas of optical communications for detector readout and control and also local voltage control for the front-end chips, which become more vulnerable to failure as feature sizes (and voltage failure levels) decrease. No funds are required for these projects this year. The funded projects have all indicated what they would do over a two-year period, allowing a better understanding of what to expect in the second year and the rate at which progress will be made. They will each be evaluated toward the end of the first year to see how the work is progressing. Funding Request: Upgrade R&D for FY 05 BNL87,500 Hampton20,000 LBNL165,000 UCSC100,000 Univ. of Hawaii63,500 Univ. of New Mexico63,500 Total499,500

14 Possible Detector Unit

15 Schematic of the Prototype Stripixel Detector PHENIX Upgrade σ y = ~25 μm Test results:

16 Innermost Detectors

17 Status Report of ID Upgrade Activities at BNL A new Silicon Detector Lab has been established and renovated in the BNL physics building for upgrade R&D activities. A readout system and front-end cards using low-noise ICs (Viking chips) from IDEAS, Norway has just recently become operational. We intend to use the system to test stripixel detectors and perhaps other detectors. We are initiating the evaluation of two types of ICs, the VA1’ and the VA2TA chip. We will select one to be our standard for testing the stripixel detectors. A second system (The ABCD Test Station) for high frequency/high speed tests of stripixel detectors and staves is being assembled in the Si-Det lab. Most of the parts were obtained from one of the Santa Cruz ABCD test stations. We are awaiting delivery of some modules from LBNL as well as one commercial component. The first batch of p-on-n stripixels is currently being fabricated. This fabrication is expected to be completed in January A geometrically identical batch of stripixels will then be started. This batch however will be fabricated on radiation hard p-type material. Testing of the p-on-n stripixel detectors will be done with the Viking readout system and will begin in February. Simulations of occupancies in the inner detector at SLHC has begun (P. Nevski) to provide guidance on the segmentation required in the inner detector region. Currently work is focusing on transferring the detector geometry into the ATHENA framework to make it easier to change detector configurations. Some initial consideration of serial power laddering schemes (J. Kiersted) has started and will be ongoing.

18 Status Report of ID Upgrade Activities at LBNL: Hybrid for integrated stave for silicon strips under development: schematics and basic layout complete. Detailed layout in progress. LBNL hosted a meeting and design review on Jan 24 and 25, with U.S. groups and some European participation. Stave assembly hardware transferred from FNAL. Stave and hybrid testing electronics and fixtures installed in new lab area. First chip in 0.13 micron CMOS has been received, now being evaluated. Chip has 20 pixel front-ends, and a variety of digital shift register and latch structures for SEU measurements. Spice models for the front-end are ready for comparison to measurements.

19 Status Report of ID Upgrade Activities at UCSC SiGe: Six arrays of test structures made with the IBM SiGe process were irradiated at CERN to fluences from 4 x up to 1 x The arrays contain bipolar transistors of several sizes as well as matched pairs. The electrical characteristics were measured prior to irradiation. We are now evaluating the irradiated devices. Assuming these tests show adequate radiation hardness of these devices, we intend to irradiate some more devices with neutrons and gammas. This will be done in early We will then build post-rad SPICE models for the process and proceed with a front-end IC design. P-type Substrates: We have received p-type test structures from RD50 collaborators and have characterized their electrical performance. This work is motivated by continuing good news about the radiation hardness of p-type detectors. G.-L. Casse et al, had reported that the charge collection after very high irradiation is significantly higher than previously measured trapping times would lead us to expect when extrapolated linearly to SLHC fluences. Now P. Allport et al, reported at the Nov. IEEE meeting that room temperature anti-annealing is almost non-existent. This means that one will be able to control the depletion voltages much more trivially at the SLHC by keeping the detectors cold only during data taking.

20 Status Report for 3-D Collaboration University of Hawaii has produced 48 small sensors designed to fit the ATLAS pixel readout chip. These have been tested and some will be bump bonded in industry. Once returned these assemblies will be tested at LBNL using pixel test setup. Indium-bump bonding to readout chips at Stanford is also in progress. FY05 funding will then support a fabrication based on what has been learned. University of New Mexico has purchased equipment to be able to measure the very fast signals expected for 3-D detectors. Kentech Instruments APG1 laser pulser (150 ps risetime). Picoprobe Model 35 (20 ps risetime). LeCroy 6200A 2 GHz (225 ps risetime) oscilloscope.

21 Funding Plan-Longer Term FY05FY06FY07FY08 Silicon Upgrade Detector 499k$1,549k$1,653k$2,765k$ Remainder of Detector 0k$509k$516k$566k$ Total 499k$2,057k$2,168k$3,331k$

22 Program for Next Year (1)Work in progress on tracker will next year saturate planned funding. (2)For muon system and tile calorimetry, work will involve simulations to continue the study of rate effects on these systems. Eventual high fluence tests of electronics will be needed. (3)A likely new effort will look at the possibility of a track trigger to enhance the ability to trigger on B mesons and tau leptons. (4)Begin work on Upgrade for the Liquid Argon, which is system most affected after tracker. Issues: Radiation effects on charge collection, including poisoning of the LAr and layer build-up on the electrodes. Start work on improved electronics, particularly front-end boards.