Håvard Gjersdal

• Abbott, Brad; Albert, Justin B.; Alberti, Fabrizio A.; Alex, Markus; Alimonti, Gianluca; Alkire, Steven; Allport, Philip P.; Altenheiner, Silke; Ancu, Lucian Stefan; Anderssen, Eric D.; Dorholt, Ole; Franconi, Laura; Gjersdal, Håvard; Ould-Saada, Farid; Røhne, Ole Myren; Sandaker, Heidi; Kastanas, Alex; Stugu, Bjarne; Andreani, Allesandro; Andreazza, Attilio; Arguin, Jean-Francois; Axen, Bradley; Backhaus, Malte; Balbi, Gabriele; Ballansat, Jacques; Barbero, Marlon B.; Barbier, Gérard; Bassalat, Ahmed; Bates, Richard Laurence; Battaglia, Marco; Baudin, Pierre; Beau, Tristan; Beccherle, Roberto; Bell, Andrew S.; Benoit, Mathieu; Bertsche, Callie; Bertsche, David; Bindi, Marcello; Bomben, Marco; Borri, Marcello; Bortolin, Claudio; Bousson, Nicolas; Boyd, Russell G.; Breugnon, Patrick; Bruni, Graziano; Bruschi, Marco; Buchholz, Peter; Budun, Ercan; Buttar, Craig M.; Clark, Allan G. & ATLAS, Pixel Collaboration (2018). Production and integration of the ATLAS Insertable B-Layer. Journal of Instrumentation.  ISSN 1748-0221.  13:T05008(5), s 1- 93 . doi: 10.1088/1748-0221/13/05/T05008
• Frühwirth, R.; Bergauer, T.; Friedl, M; Gjersdal, Håvard; Irmler, C.; Spielauer, T.; Strandlie, Are & Valentan, M. (2013). Analysis of beam test data by global optimization methods. Nuclear Instruments and Methods in Physics Research Section A : Accelerators, Spectrometers, Detectors and Associated Equipment.  ISSN 0168-9002.  732, s 79- 82 . doi: 10.1016/j.nima.2013.05.038 Show summary

  Successful track reconstruction in a silicon tracking device depends on the quality of the alignment, on the knowledge of the sensor resolution, and on the knowledge of the amount of material traversed by the particles. We describe algorithms for the concurrent estimation of alignment parameters, sensor resolutions and material thickness in the context of a beam test setup. They are based on a global optimization approach and are designed to work both with and without prior information from a reference telescope. We present results from simulated and real beam test data.

• Gjersdal, Håvard; Frühwirth, Rudolf; Nadler, Moritz & Strandlie, Are (2013). Optimizing track reconstruction by simultaneous estimation of material and resolutions. Journal of Instrumentation.  ISSN 1748-0221.  8 . doi: 10.1088/1748-0221/8/01/P01009 Show summary

  We present methods to improve the fit quality of reconstructed particle tracks by simultaneously estimating the amounts of traversed material and the sensor resolutions from tracker data. The performance of the methods has been compared by simulation studies. The methods have also been validated on real test beam data. Results from this validation, showing an improved quality of the track fit, are presented.

• Gjersdal, Håvard; Bolle, Erlend; Borri, M; Da Via, C; Dorholt, Ole; Fazio, S; Grenier, Philippe; Grinstein, S; Hansson, P; Hasi, J; Hugging, F; Jackson, P; Kenney, C; Kocian, M; La Rosa, A; Mastroberardino, A; Nordahl, Per Einar; Rivero, F; Røhne, Ole Myren; Sandaker, Heidi; Sjøbæk, Kyrre Ness; Slaviec, T; Su, D; Tsung, J; Tsybychev, D; Wermes, N & Young, C (2011). Tracking efficiency and charge sharing of 3D silicon sensors at different angles in a 1.4T magnetic field. Nuclear Instruments and Methods in Physics Research Section A : Accelerators, Spectrometers, Detectors and Associated Equipment.  ISSN 0168-9002.  636, s S42- S49 . doi: 10.1016/j.nima.2010.04.083
• Grenier, Philippe; Alimonti, G; Barbero, M; Bates, R; Bolle, Erlend; Borri, M; Boscardin, M; Buttar, C; Capua, M; Cavalli-Sforza, M; Cobal, M; Cristofoli, A; Dalla Betta, F; Darbo, G; Da Via, C; Devetak, E; DeWilde, B; Di Girolamo, B; Dobos, D; Einsweiler, K; Esseni, D; Fazio, S; Fleta, C; Freestone, J; Gallrapp, C; Garcia-Sciveres, M; Gariano, G; Gemme, C; Giordani, MP; Gjersdal, Håvard; Grinstein, S; Hansen, Trond Andreas; Hansen, Thor-Erik; Hansson, P; Hasi, J; Helle, Kristine Indahl; Hoeferkamp, M; Hugging, F; Jackson, P; Jakobs, K; Kalliopuska, J; Karagounis, M; Kenney, C; Kohler, M; Kocian, M; Kok, Angela Chun Ying; Kolya, S; Korokolov, I; Kostyukhin, V; Kruger, H; La Rosa, A; Lai, CH; Lietaer, Nicolas; Lozano, M; Mastroberardino, A; Micelli, A; Nellist, C; Oja, A; Oshea, V; Padilla, C; Palestri, P; Parker, S; Parzefall, U; Pater, J; Pellegrini, G; Pernegger, H; Piemonte, C; Pospisil, S; Povoli, M; Roe, S; Røhne, Ole Myren; Ronchin, S; Rovani, A; Ruscino, E; Sandaker, Heidi; Seidel, S; Selmi, L; Silverstein, D; Sjøbæk, Kyrre Ness; Slavicek, T; Stapnes, Steinar; Stugu, Bjarne; Stupak, J; Su, D; Susinno, G; Thompson, R; Tsung, JW; Tsybychev, D; Watts, SJ; Wermes, N; Young, C & Zorzi, N (2011). Test beam results of 3D silicon pixel sensors for the ATLAS upgrade. Nuclear Instruments and Methods in Physics Research Section A : Accelerators, Spectrometers, Detectors and Associated Equipment.  ISSN 0168-9002.  638(1), s 33- 40 . doi: 10.1016/j.nima.2011.01.181 Show summary

  Results on beam tests of 3D silicon pixel sensors aimed at the ATLAS Insertable B-Layer and High Luminosity LHC (HL-LHC) upgrades are presented. Measurements include charge collection, tracking efficiency and charge sharing between pixel cells, as a function of track incident angle, and were performed with and without a 1.6 T magnetic field oriented as the ATLAS inner detector solenoid field. Sensors were bump-bonded to the front-end chip currently used in the ATLAS pixel detector. Full 3D sensors, with electrodes penetrating through the entire wafer thickness and active edge, and double-sided 3D sensors with partially overlapping bias and read-out electrodes were tested and showed comparable performance.

• Hansson, P; Balbuena, J; Barrera, C; Bolle, Erlend; Borri, M; Boscardin, M; Chmeissan, M; Dalla Betta, GF; Darbo, G; Da Via, C; Devetak, E; DeWilde, B; Su, D; Dorholt, Ole; Fazio, S; Fleta, C; Gemme, C; Giordani, M; Gjersdal, Håvard; Grenier, P; Grinstein, S; Hasi, J; Helle, Kristine Indahl; Huegging, F; Jackson, P; Kenney, C; Kocian, M; Korolkov, I; La Rosa, A; Mastroberardino, A; Micelli, A; Nellist, C; Nordahl, Per Einar; Rivero, F; Røhne, Ole Myren; Sandaker, Heidi; Silverstein, D; Sjøbæk, Kyrre Ness; Slaviec, T; Stupak, J; Troyano, I; Tsung, J; Tsybychev, D; Wermes, N & Young, C (2011). 3D silicon pixel sensors: Recent test beam results. Nuclear Instruments and Methods in Physics Research Section A : Accelerators, Spectrometers, Detectors and Associated Equipment.  ISSN 0168-9002.  628(1), s 216- 220 . doi: 10.1016/j.nima.2010.06.321
• Micelli, A.; Helle, Kristine Indahl; Sandaker, Heidi; Stugu, Bjarne; Barbero, M; Hugging, F; Karagounis, M; Kostyukhin, V; Krüger, Harald; Tsung, JW; Wermes, N; Capua, M; Fazio, S; Mastroberardino, A; Susinno, G; Gallrapp, C; Di Girolamo, B; Dobos, D; La Rosa, A; Pernegger, H; Roe, S; Slavicek, T; Pospisil, S; Jakobs, K; Kohler, M; Parzefall, U; Darbo, G; Gariano, G; Gemme, C; Rovani, A; Ruscino, E; Butter, C; Bates, R; Oshea, V; Parker, S; Cavalli-Sforza, M; Grinstein, S; Korokolov, I; Pradilla, C; Einsweiler, K; Garcia-Sciveres, M; Borri, M; Da Via, C; Freestone, J; Kolya, S; Lai, CH; Nellist, C; Pater, J; Thompson, R; Watts, SJ; Hoeferkamp, M; Seidel, S; Gjersdal, Håvard; Sjøbæk, Kyrre Ness; Stapnes, Steinar; Røhne, Ole Myren; Su, D; Young, C; Hansson, P; Grenier, P; Hasi, J; Kenney, C; Kocian, M; Jackson, P; Silverstein, D; Davetak, H; DeWilde, B; Tsybychev, D; Dalla Betta, GF; Gabos, P; Povoli, M; Cobal, M; Giordani, MP; Selmi, L; Cristofoli, A; Esseni, D; Palestri, P; Fleta, C; Lozano, M; Pellegrini, G; Boscardin, M; Bagolini, A; Piemonte, C; Ronchin, S; Zorzi, N; Hansen, Thor-Erik; Hansen, Trond Andreas; Kok, Angela Chun Ying; Lietaer, Nicolas; Kalliopuska, J; Oja, A & Bolle, Erlend (2011). 3D-FBK pixel sensors: Recent beam tests results with irradiated devices. Nuclear Instruments and Methods in Physics Research Section A : Accelerators, Spectrometers, Detectors and Associated Equipment.  ISSN 0168-9002.  650(1), s 150- 157 . doi: 10.1016/j.nima.2010.12.209 Show summary

  The Pixel Detector is the innermost part of the ATLAS experiment tracking device at the Large Hadron Collider, and plays a key role in the reconstruction of the primary vertices from the collisions and secondary vertices produced by short-lived particles. To cope with the high level of radiation produced during the collider operation, it is planned to add to the present three layers of silicon pixel sensors which constitute the Pixel Detector, an additional layer (Insertable B-Layer, or IBL) of sensors. 3D silicon sensors are one of the technologies which are under study for the IBL. 3D silicon technology is an innovative combination of very-large-scale integration and Micro-Electro-Mechanical-Systems where electrodes are fabricated inside the silicon bulk instead of being implanted on the wafer surfaces. 3D sensors, with electrodes fully or partially penetrating the silicon substrate, are currently fabricated at different processing facilities in Europe and USA. This paper reports on the 2010 June beam test results for irradiated 3D devices produced at FBK (Trento, Italy). The performance of these devices, all bump-bonded with the ATLAS pixel FE-I3 read-out chip, is compared to that observed before irradiation in a previous beam test.

View all works in Cristin

• Gjersdal, Håvard (2014). Test beam track reconstruction and analysis of ATLAS 3D pixel detectors.

View all works in Cristin