1 / 39

David Radford ORNL Physics Division JUSTIPEN February 2009

rona
Download Presentation

David Radford ORNL Physics Division JUSTIPEN February 2009

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

    1. Status of GRETINA

    2. Status of GRETINA

    5. GRETINA - People Contractor Project Manager: I-Yang Lee (LBNL)? GRETINA Advisory Committee (GAC): Con Beausang (U. of Richmond)? Doug Cline (U. of Rochester)? Thomas Glasmacher (MSU / NSCL)? Kim Lister (ANL)? Augusto Macchiavelli (LBNL) David Radford (ORNL) (Chair)? Mark Riley (Florida State U.)? Demetrios Sarantites (Washington U.)? Kai Vetter (LLNL)? Working Groups and chairs Physics M. A. Riley    (FSU)? Detectors A. O. Macchiavelli (LBNL)? Electronics D. C. Radford (ORNL)? Software M. Cromaz  (LBNL)? Aux. Detectors D.G. Sarantites (WUSTL)?

    7. First Quadruple Cluster (Q1)?

    8. Second Quadruple Cluster (Q2)?

    10. Electronics

    11. Computing System

    13. Examples of calculated signals: Sensitivity to position

    14. Current algorithm is a hybrid: AGS + SQP Pair-wise Adaptive Grid Search ~200,000 two-par. least-squares fits per segment (for energies)? in ~2 ms Non-linear Least-Squares (a.k.a. SQP)? Have also been developing Singular Value Decomposition Collaboration with Tech-X Corp., funded under DOE SBIR Developed SVD + SQP hybrid algorithm - SVD on a coarse grid, with 250 eigenvalues - Localize interaction regions - Estimate number of interactions in each segment Approx. 25% faster, but slightly poorer fits; further work planned Also demonstrated speed-up of SVD algorithm by factor 30 to 40 using Graphics Processing Units (GPUs) rather than CPUs. CPU time required : AGS ~ O(500n)? SQP ~ O(n + ?n2)? for n interactions SVD ~ O(n)? Signal Decomposition Algorithm

    15. Status of Signal Decomposition Algorithm Three orders of magnitude improvement in CPU time; now meets timing requirements Developed new optimized, irregular grid for the basis signals Developed method to accurately correct calculated signals for preamplifier response and for two types of cross talk Incorporated fitting of signal start time t0 Much improved fits (?2 values)? Can handle any number of hit detector segments, each with up to two interactions Although some work remains to be done, we have demonstrated that the problem of signal decomposition for GRETINA is solved

    18. Collimated Cs-source test

    19. Scanning-table coincident-data test

    20. Workshop in Oct 2007, organized by the GAC Plan for optimizing physics impact of GRETINA following completion in March 2011 Participation and presentation by Prof. Shimoura, U. of Tokyo; expressed interest in hosting GRETINA at RIKEN Report prepared by GAC, submitted to DOE Unanimous agreement on a plan for the first physics campaigns Commissioning runs at LBNL, starting March 2001, coupled to BGS Then rotate to other national laboratories, ~ 6 month campaigns Suggested sequence for the first cycle: MSU - NSCL ORNL - HRIBF ANL - ATLAS “We look forward to further discussions with our Japanese colleagues and are excited about the possibility of future collaborations.” Unique opportunities at RIKEN: Beams, auxiliary instruments, expertise Siting

    21. Construction is proceeding, on schedule, on budget Received CD2B / 3B approval Oct 2007 Signal decomposition problem is solved Scheduled completion date: 2 March 2011 (Wed)? We have proposed a plan for the first round of physics campaigns Next stage: Full 4? steradians GRETA received strong community support in LRP “… construction of GRETA should begin upon successful completion of GRETINA” Summary

    22. LBNL: I-Yang Lee Overall project manager and source of all wisdom! A. Machiavelli, M. Cromaz, P. Fallon, M. Descovich, J. Pavan, many others Detectors, DAQ, in-beam data analysis, simulations, electric field calc'ns, etc. Sergio Zimmermann, John Joseph, Carl Lionberger, many others Electronics, engineering, computing, etc. GRETINA Advisory Committee and Working Group Leaders Endless proposal writing, review preparation, working group meetings, conference calls, ... John Anderson (ANL)? Trigger system Karin Lagergren (ORNL / UTK)? Signal calculation code in C, Optimized pseudo-cylindrical grid Tech-X Corp, especially Isidoros Doxas SVD development

    23. Backup Slides

    25. In-Beam test at LBNL

    26. In-Beam test at MSU

    27. ORNL Installation

    28. Cross-talk Differential cross talk arises from capacitive coupling between the inputs to the preamplifiers (some due to physical capacitance of the detector) Can be modelled well in SPICE, but needs to be carefully characterized in reality

    29. Fitting to Extract Cross-Talk Parameters

    30. Why is it hard?

    31. Comparison – Old Basis and Code vs. New

    34. Singular Value Decomposition

    35. Singular Value Decomposition

    36. Singular Value Decomposition

    37. 1? ? 4? coverage, 28 ? 120 detectors

    38. How do extreme proton-to-neutron asymmetries affect nuclear properties, such as shell structure and collectivity? What are the properties of nuclei at the limits of mass and charge? What are the properties of nuclei at the limits of angular momentum? Nuclear astrophysics, fundamental interactions and rare processes

    39. Gamma-Ray Tracking “… The construction of GRETA should begin upon successful completion of GRETINA. This gamma-ray energy tracking array will enable full exploitation of compelling science opportunities in nuclear structure, nuclear astrophysics, and weak interactions.” GRETA in the 2007 NSAC Long Range Plan

    40. GRETA Cost and Schedule

More Related