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32 results on '"Holland, S. E."'

1. Confirmation of the spectral excess in DAMIC at SNOLAB with skipper CCDs

Author

Aguilar-Arevalo, A., Arnquist, I., Avalos, N., Barak, L., Baxter, D., Bertou, X., Bloch, I. M., Botti, A. M., Cababie, M., Cancelo, G., Castelló-Mor, N., Cervantes-Vergara, B. A., Chavarria, A. E., Cortabitarte-Gutiérrez, J., Crisler, M., Cuevas-Zepeda, J., Dastgheibi-Fard, A., De Dominicis, C., Deligny, O., Drlica-Wagner, A., Duarte-Campderros, J., D'Olivo, J. C., Essig, R., Estrada, E., Estrada, J., Etzion, E., Favela-Perez, F., Gadola, N., Gaïor, R., Holland, S. E., Hossbach, T., Iddir, L., Kilminster, B., Korn, Y., Lantero-Barreda, A., Lawson, I., Lee, S., Letessier-Selvon, A., Loaiza, P., Lopez-Virto, A., Luoma, S., Marrufo-Villalpando, E., McGuire, K. J., Moroni, G. F., Munagavalasa, S., Norcini, D., Orly, A., Papadopoulos, G., Paul, S., Perez, S. E., Piers, A., Privitera, P., Robmann, P., Rodrigues, D., Saffold, N. A., Scorza, S., Settimo, M., Singal, A., Smida, R., Sofo-Haro, M., Stefanazzi, L., Stifter, K., Tiffenberg, J., Traina, M., Uemura, S., Vila, I., Vilar, R., Volansky, T., Warot, G., Yajur, R., Yu, T-T., and Zopounidis, J-P.

Subjects
Astrophysics - Cosmology and Nongalactic Astrophysics, High Energy Physics - Experiment, Nuclear Experiment
Abstract

We present results from a 3.25 kg-day target exposure of two silicon charge-coupled devices (CCDs), each with 24 megapixels and skipper readout, deployed in the DAMIC setup at SNOLAB. With a reduction in pixel readout noise of a factor of 10 relative to the previous detector, we investigate the excess population of low-energy events in the CCD bulk previously observed above expected backgrounds. We address the dominant systematic uncertainty of the previous analysis through a depth fiducialization designed to reject surface backgrounds on the CCDs. The measured bulk ionization spectrum confirms the presence of an excess population of low-energy events in the CCD target with characteristic rate of ${\sim}7$ events per kg-day and electron-equivalent energies of ${\sim}80~$eV, whose origin remains unknown., Comment: 8 pages, 4 figures

Published
2023
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2. Solid State Detectors and Tracking for Snowmass

Author

Affolder, A., Apresyan, A., Worm, S., Albrow, M., Ally, D., Ambrose, D., Anderssen, E., Apadula, N., Asenov, P., Armstrong, W., Artuso, M., Barbier, A., Barletta, P., Bauerdick, L., Berry, D., Bomben, M., Boscardin, M., Brau, J., Brooks, W., Breidenbach, M., Buckley, J., Cairo, V., Caputo, R., Carpenter, L., Centis-Vignali, M., Cerullo, M., Collu, A., Chlebana, F., Dalla-Betta, G. -F., Demarteau, M., Deptuch, G., Di Petrillo, K., D'Amen, G., Dragone, A., Fourches, N. T., Garcia-Sciveres, M., Giacomini, G., Gingu, C., Graf, N., Grace, C., Griso, S., Greiner, L., Haber, C., Haller, G., Harris, K., Heim, T., Heinz, U., Heller, R., Hedges, M. T., Herbst, R., Hoeferkamp, M. R., Holmes, T., Holland, S. E., Hsu, S. -C., Islam, R., Jadhav, M., Jindariani, S., Joosten, S., Jung, A., Karmarkar, S., Kenney, C., Kierans, C., Kim, J., Kim, S., Klein, S., Koshy, A., Krizka, K., Lai, A., Lee, L., Linssen, L., Lipton, R., Liu, T., Madrid, C., Mahajan, T., Markiewicz, T., Markovic, B., Mazza, S., Mazziotta, M., Mei, Y., Merkel, P., Metcalfe, J., Meziani, Z. -E., Minns, A., Moscatelli, F., Murat, P., Muth, J., Nachman, B., Nahn, S., Narain, M., Narayanan, E. A., Nelson, T., Nielsen, J., Oktyabrsky, S., Ott, J., Palomo, F. R., Passeri, D., Patti, R., Peltola, T., Pena, C., Peng, C., Renard, C., Reimer, P., Rogan, C., Rota, L., Sadrozinski, H., Segal, J., Schwartzman, A., Schumm, B., Scott, M., Seidel, S., Seiden, A., Sekely, B., Shi, X., Sichtermann, E., Sinev, N., Sonneveld, J., Spiegel, L., Steinhebel, A., Strom, D., Sultan, D. M. S., Sumant, A., Tokranov, V., Tricoli, A., Trischuk, W., Tumasyan, A., Uplegger, L., Vernieri, C., Wang, H., Wagenknecht, P., Weber, H., Xie, S., Yakimov, M., Ye, Z., Young, C., and Zurek, M.

Subjects
Physics - Instrumentation and Detectors, High Energy Physics - Experiment
Abstract

Tracking detectors are of vital importance for collider-based high energy physics (HEP) experiments. The primary purpose of tracking detectors is the precise reconstruction of charged particle trajectories and the reconstruction of secondary vertices. The performance requirements from the community posed by the future collider experiments require an evolution of tracking systems, necessitating the development of new techniques, materials and technologies in order to fully exploit their physics potential. In this article we summarize the discussions and conclusions of the 2022 Snowmass Instrumentation Frontier subgroup on Solid State and Tracking Detectors (Snowmass IF03)., Comment: for the Snowmass Instrumentation Frontier Solid State Detector and Tracking community

Published
2022

3. Fast Timing With Silicon Carbide Low Gain Avalanche Detectors

Author

Barletta, P., Cerullo, M., Haber, C., Holland, S. E., Muth, J., and Sekely, B.

Subjects
Physics - Instrumentation and Detectors
Abstract

4H-Silicon Carbide, when considered as a material for the fabrication of Low Gain Avalanche Detectors for particle timing and position measurement, offers potential advantages over Silicon. We discuss an ongoing study of this material aimed at the fabrication and test of prototype fast timing sensors. This work is well aligned with technical directions identified in the recent Department of Energy study, Basic Research Needs for High Energy Physics Detector Research and Development., Comment: Submitted to Snowmass 2021

Published
2022

4. EXCESS workshop: Descriptions of rising low-energy spectra

Author

Adari, P., Aguilar-Arevalo, A., Amidei, D., Angloher, G., Armengaud, E., Augier, C., Balogh, L., Banik, S., Baxter, D., Beaufort, C., Beaulieu, G., Belov, V., Gal, Y. Ben, Benato, G., Benoît, A., Bento, A., Bergé, L., Bertolini, A., Bhattacharyya, R., Billard, J., Bloch, I. M., Botti, A., Breier, R., Bres, G., Bret, J-. L., Broniatowski, A., Brossard, A., Bucci, C., Bunker, R., Cababie, M., Calvo, M., Camus, P., Cancelo, G., Canonica, L., Cappella, F., Cardani, L., Caron, J. -F., Casali, N., del Castello, G., Cazes, A., Cerulli, R., Vergara, B. A. Cervantes, Chaize, D., Chapellier, M., Chaplinsky, L., Charlieux, F., Chaudhuri, M., Chavarria, A. E., Chemin, G., Chen, R., Chen, H., Chierchie, F., Colantoni, I., Colas, J., Cooley, J., Coquillat, J. -M., Corcoran, E. C., Crawford, S., Crisler, M., Cruciani, A., Cushman, P., D'Addabbo, A., D'Olivo, J. C., Dastgheibi-Fard, A., De Jésus, M., Deng, Y., Dent, J. B., Depaoli, E. L., Dering, K., Dharani, S., Di Lorenzo, S., Drlica-Wagner, A., Dumoulin, L., Durnford, D., Dutta, B., Einfalt, L., Erb, A., Erhart, A., Essig, R., Estrada, J., Etzion, E., Exshaw, O., Favela-Perez, F., Feilitzsch, F. v., Moroni, G. Fernandez, Iachellini, N. Ferreiro, Ferriol, S., Fichtinger, S., Figueroa-Feliciano, E., Filippini, J. -B., Filosofov, D., Formaggio, J. A., Friedl, M., Fuard, S., Fuchs, D., Fuss, A., Gaïor, R., Garai, A., Garrah, C., Gascon, J., Gerbier, G., Ghaith, M., Ghete, V. M., Gift, D., Giomataris, I., Giroux, G., Giuliani, A., Gorel, P., Gorla, P., Goupy, C., Goupy, J., Goy, C., Gros, M., Gros, P., Guardincerri, Y., Guerin, C., Guidi, V., Guillaudin, O., Gupta, S., Guy, E., Harrington, P., Hauff, D., Heine, S. T., Hertel, S. A., Holland, S. E., Hong, Z., Hoppe, E. W., Hossbach, T. W., Ianigro, J. -C., Iyer, V., Jastram, A., Ješkovský, M., Jin, Y., Jochum, J., Johnston, J. P., Juillard, A., Karaivanov, D., Kashyap, V., Katsioulas, I., Kazarcev, S., Kaznacheeva, M., Kelly, F., Kilminster, B., Kinast, A., Klinkenberg, L., Kluck, H., Knights, P., Korn, Y., Kraus, H., von Krosigk, B., Kubik, A., Kurinsky, N. A., Lamblin, J., Langenkämper, A., Langrock, S., Lasserre, T., Lattaud, H., Lautridou, P., Lawson, I., Lee, S. J., Lee, M., Letessier-Selvon, A., Lhuillier, D., Li, M., Lin, Y. -T., Lubashevskiy, A., Mahapatra, R., Maludze, S., Mancuso, M., Manthos, I., Marini, L., Marnieros, S., Martin, R. D., Matalon, A., Matthews, J., Mauri, B., Mayer, D. W., Mazzolari, A., Mazzucato, E., Theenhausen, H. Meyer zu, Michielin, E., Minet, J., Mirabolfathi, N., Mirbach, K. v., Misiak, D., Mitra, P., Mocellin, J-. L., Mohanty, B., Mokina, V., Mols, J. -P., Monfardini, A., Mounier, F., Munagavalasa, S., Muraz, J. -F., Navick, X. -F., Neep, T., Neog, H., Neyrial, H., Nikolopoulos, K., Nilima, A., Nones, C., Novati, V., O'Brien, P., Oberauer, L., Olivieri, E., Olmi, M., Onillon, A., Oriol, C., Orly, A., Orrell, J. L., Ortmann, T., Overman, C. T., Pagliarone, C., Palušová, V., Pari, P., Patel, P. K., Pattavina, L., Petricca, F., Piers, A., Pinckney, H. D., Piro, M. -C., Platt, M., Poda, D., Ponomarev, D., Potzel, W., Povinec, P., Pröbst, F., Privitera, P., Pucci, F., Ramanathan, K., Real, J. -S., Redon, T., Reindl, F., Ren, R., Robert, A., Da Rocha, J., Rodrigues, D., Rogly, R., Rothe, J., Rowe, N., Rozov, S., Rozova, I., Saab, T., Saffold, N., Salagnac, T., Sander, J., Sanglard, V., Santos, D., Sarkis, Y., Savu, V., Savvidis, G., Savvidis, I., Schönert, S., Schäffner, K., Schermer, N., Schieck, J., Schmidt, B., Schmiedmayer, D., Schwertner, C., Scola, L., Settimo, M., Shevchik, Ye., Sibille, V., Sidelnik, I., Singal, A., Smida, R., Haro, M. Sofo, Soldner, T., Stachurska, J., Stahlberg, M., Stefanazzi, L., Stodolsky, L., Strandhagen, C., Strauss, R., Stutz, A., Thomas, R., Thompson, A., Tiffenberg, J., Tomei, C., Traina, M., Uemura, S., Usherov, I., Vagneron, L., Van De Pontseele, W., Fernandez, F. A. Vazquez de Sola, Vidal, M., Vignati, M., Virto, A. L., Vivier, M., Volansky, T., Wagner, V., Wagner, F., Walker, J., Ward, R., Watkins, S. L., Wex, A., Willers, M., Wilson, M. J., Winslow, L., Yakushev, E., Yu, T. -T., Zampaolo, M., Zaytsev, A., Zema, V., Zinatulina, D., and Zolotarova, A.

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics, Physics - Instrumentation and Detectors
Abstract

Many low-threshold experiments observe sharply rising event rates of yet unknown origins below a few hundred eV, and larger than expected from known backgrounds. Due to the significant impact of this excess on the dark matter or neutrino sensitivity of these experiments, a collective effort has been started to share the knowledge about the individual observations. For this, the EXCESS Workshop was initiated. In its first iteration in June 2021, ten rare event search collaborations contributed to this initiative via talks and discussions. The contributing collaborations were CONNIE, CRESST, DAMIC, EDELWEISS, MINER, NEWS-G, NUCLEUS, RICOCHET, SENSEI and SuperCDMS. They presented data about their observed energy spectra and known backgrounds together with details about the respective measurements. In this paper, we summarize the presented information and give a comprehensive overview of the similarities and differences between the distinct measurements. The provided data is furthermore publicly available on the workshop's data repository together with a plotting tool for visualization., Comment: 44 pages, 20 figures; Editors: A. Fuss, M. Kaznacheeva, F. Reindl, F. Wagner; updated copyright statements and funding information

Published
2022
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5. Quantum efficiency modeling for a thick back-illuminated astronomical CCD

Author

Groom, D. E., Haque, S., Holland, S. E., and Kolbe, W. F.

Subjects
Physics - Applied Physics
Abstract

The quantum efficiency and reflectivity of thick, back-illuminated CCD's being fabricated at LBNL for astronomical applications are modeled and compared with experiment. The treatment differs from standard thin-film optics in that (a) absorption is permitted in any film, (b) the 200--500~$\mu$m thick silicon substrate is considered as a thin film in order to observe the fringing behavior at long wavelengths, and (c) by using approximate boundary conditions, absorption in the surface films is separated from absorption in the substrate. For the quantum efficiency measurements the CCD's are normally operated as CCD's, usually at $T = -140^\circ$C, and at higher temperatures as photodiodes. They are mounted on mechanical substrates. Reflectivity is measured on air-backed wafer samples at room temperature. The agreement between model expectation and quantum efficiency measurement is in general satisfactory., Comment: 25 pages, 13 figures

Published
2017
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6. The Dark Energy Camera

Author

Flaugher, B., Diehl, H. T., Honscheid, K., Abbott, T. M. C., Alvarez, O., Angstadt, R., Annis, J. T., Antonik, M., Ballester, O., Beaufore, L., Bernstein, G. M., Bernstein, R. A., Bigelow, B., Bonati, M., Boprie, D., Brooks, D., Buckley-Geer, E. J., Campa, J., Cardiel-Sas, L., Castander, F. J., Castilla, J., Cease, H., Cela-Ruiz, J. M., Chappa, S., Chi, E., Cooper, C., da Costa, L. N., Dede, E., Derylo, G., DePoy, D. L., de Vicente, J., Doel, P., Drlica-Wagner, A., Eiting, J., Elliott, A. E., Emes, J., Estrada, J., Neto, A. Fausti, Finley, D. A., Flores, R., Frieman, J., Gerdes, D., Gladders, M. D., Gregory, B., Gutierrez, G. R., Hao, J., Holland, S. E., Holm, S., Huffman, D., Jackson, C., James, D. J., Jonas, M., Karcher, A., Karliner, I., Kent, S., Kessler, R., Kozlovsky, M., Kron, R. G., Kubik, D., Kuehn, K., Kuhlmann, S., Kuk, K., Lahav, O., Lathrop, A., Lee, J., Levi, M. E., Lewis, P., Li, T. S., Mandrichenko, I., Marshall, J. L., Martinez, G., Merritt, K. W., Miquel, R., Munoz, F., Neilsen, E. H., Nichol, R. C., Nord, B., Ogando, R., Olsen, J., Palio, N., Patton, K., Peoples, J., Plazas, A. A., Rauch, J., Reil, K., Rheault, J. -P., Roe, N. A., Rogers, H., Roodman, A., Sanchez, E., Scarpine, V., Schindler, R. H., Schmidt, R., Schmitt, R., Schubnell, M., Schultz, K., Schurter, P., Scott, L., Serrano, S., Shaw, T. M., Smith, R. C., Soares-Santos, M., Stefanik, A., Stuermer, W., Suchyta, E., Sypniewski, A., Tarle, G., Thaler, J., Tighe, R., Tran, C., Tucker, D., Walker, A. R., Wang, G., Watson, M., Weaverdyck, C., Wester, W., Woods, R., and Yanny, B.

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

The Dark Energy Camera is a new imager with a 2.2-degree diameter field of view mounted at the prime focus of the Victor M. Blanco 4-meter telescope on Cerro Tololo near La Serena, Chile. The camera was designed and constructed by the Dark Energy Survey Collaboration, and meets or exceeds the stringent requirements designed for the wide-field and supernova surveys for which the collaboration uses it. The camera consists of a five element optical corrector, seven filters, a shutter with a 60 cm aperture, and a CCD focal plane of 250 micron thick fully-depleted CCDs cooled inside a vacuum Dewar. The 570 Mpixel focal plane comprises 62 2kx4k CCDs for imaging and 12 2kx2k CCDs for guiding and focus. The CCDs have 15 microns x15 microns pixels with a plate scale of 0.263 arc sec per pixel. A hexapod system provides state-of-the-art focus and alignment capability. The camera is read out in 20 seconds with 6-9 electrons readout noise. This paper provides a technical description of the camera's engineering, construction, installation, and current status., Comment: submitted to AJ Corresponding Authors H. T. Diehl (diehl@fnal.gov)

Published
2015
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7. Physics of Fully Depleted CCDs

Author

Holland, S. E., Bebek, C. J., Kolbe, W. F., and Lee, J. S.

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics, Physics - Instrumentation and Detectors
Abstract

In this work we present simple, physics-based models for two effects that have been noted in the fully depleted CCDs that are presently used in the Dark Energy Survey Camera. The first effect is the observation that the point-spread function increases slightly with the signal level. This is explained by considering the effect on charge-carrier diffusion due to the reduction in the magnitude of the channel potential as collected signal charge acts to partially neutralize the fixed charge in the depleted channel. The resulting reduced voltage drop across the carrier drift region decreases the vertical electric field and increases the carrier transit time. The second effect is the observation of low-level, concentric ring patterns seen in uniformly illuminated images. This effect is shown to be most likely due to lateral deflection of charge during the transit of the photogenerated carriers to the potential wells as a result of lateral electric fields. The lateral fields are a result of space charge in the fully depleted substrates arising from resistivity variations inherent to the growth of the high-resistivity silicon used to fabricate the CCDs.

Published
2014
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8. A 2K×2K High Resistivity CCD

Author

Stover, R. J., Wei, M., Ji, K., Brown, W. E., Gilmore, D. K., Holland, S. E., Groom, D. E., Levi, M. E., Palaio, N., Perlmutter, S., Amico, Paola, editor, and Beletic, James W., editor

Published
2000
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11. A 2K×2K High Resistivity CCD

Author

Stover, R. J., primary, Wei, M., additional, Ji, K., additional, Brown, W. E., additional, Gilmore, D. K., additional, Holland, S. E., additional, Groom, D. E., additional, Levi, M. E., additional, Palaio, N., additional, and Perlmutter, S., additional

Published
2000
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18. SNAP telescope

Author

Lampton, Michael L., Akerlof, C. W., Aldering, G., Amanullah, R., Astier, P., Barrelet, E., Bebek, C., Bergstrom, L., Bercovitz, J., Bernstein, G., Bester, M., Bonissent, A., Bower, C., Carithers, Jr, Commins, E. D., Day, C., Deustua, S. E., Digennaro, R., Ealet, A., Ellis, R. S., Eriksson, M., Fruchter, A., Genat, J. -F, Goldhaber, G., Goobar, A., Groom, D., Harris, S. E., Harvey, P. R., Heetderks, H. D., Holland, S. E., Huterer, D., Karcher, A., Kim, A. G., Kolbe, W., Krieger, B., Lafever, R., Lamoureux, J., Levi, M. E., Levin, D. S., Linder, E. V., Loken, S. C., Malina, R., Massey, R., Mckay, T., Mckee, S. P., Miquel, R., Mortsell, E., Mostek, N., Mufson, S., Musser, J., Nugent, P., Oluseyi, H., Pain, R., Palaio, N., Pankow, D., Perlmutter, S., Pratt, R., Prieto, E., Refregier, A., Rhodes, J., Robinson, K., Roe, N., Sholl, M., Schubnell, M., Smadja, G., Smoot, G., Spadafora, A., Gregory Tarlé, Tomasch, A., Lippe, H., Vincent, R., Walder, J. -P, and Wang, G.

Subjects
Physics
Published
2002

19. CCD research and development at Lawrence Berkeley National Laboratory

Author

Bebek, C. J., primary, Coles, R. A., additional, Denes, P., additional, Dion, F., additional, Emes, J. H., additional, Frost, R., additional, Groom, D. E., additional, Groulx, R., additional, Haque, S., additional, Holland, S. E., additional, Karcher, A., additional, Kolbe, W. F., additional, Lee, J. S., additional, Palaio, N. P., additional, Roe, N. A., additional, Tran, C. H., additional, and Wang, G., additional

Published
2012
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22. Silicon Detectors for Low Energy Particle Detection

Author

Tindall, C. S., primary, Palaio, N. P., additional, Ludewigt, B. A., additional, Holland, S. E., additional, Larson, D. E., additional, Curtis, D. W., additional, McBride, S. E., additional, Moreau, T., additional, Lin, R. P., additional, and Angelopoulos, V., additional

Published
2008
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29. Design of low-noise output amplifiers for P-channel charge-coupled devices fabricated on high-resistivity silicon

Author

Haque, S., Dion, F., Frost, R., Groulx, R., Holland, S. E., Karcher, A., Kolbe, W. F., Roe, N. A., Wang, G., and Yu, Y.

Abstract

We describe the design and optimization of low-noise, single-stage output amplifiers for p-channel charge-coupled devices (CCDs) used for scientific applications in astronomy and other fields. The CCDs are fabricated on highresistivity, 4000-5000 -cm, n-type silicon substrates. Single-stage amplifiers with different output structure designs and technologies have been characterized. The standard output amplifier is designed with an n+polysilicon gate that has a metal connection to the sense node. In an effort to lower the output amplifier readout noise by minimizing the capacitance seen at the sense node, buried-contact technology has been investigated. In this case, the output transistor has a p+polysilicon gate that connects directly to the p+sense node. Output structures with buried-contact areas as small as 2 m × 2 m are characterized. In addition, the geometry of the source-follower transistor was varied, and we report test results on the conversion gain and noise of the various amplifier structures. By use of buried-contact technology, better amplifier geometry, optimization of the amplifier biases and improvements in the test electronics design, we obtain a 45% reduction in noise, corresponding to 1.7 e- rms at 70 kpixels/sec.

Published
2012
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32. Real-time quantitative ex vivo direct autoradiography with 10 μm pixel resolution.

Author

Peng Q, Holland SE, Choong WS, Budinger TF, and Moses WW

Subjects
Algorithms, Biopsy methods, Computer Graphics, Computer Simulation, Electrons, Equipment Design, Humans, Kinetics, Monte Carlo Method, Optics and Photonics, Phantoms, Imaging, Positron-Emission Tomography methods, Radiographic Image Enhancement instrumentation, Radiographic Image Enhancement methods, Signal-To-Noise Ratio, Temperature, Tomography, Emission-Computed, Single-Photon methods, Autoradiography methods, Image Processing, Computer-Assisted methods, Neoplasms pathology
Abstract

We present three new autoradiography methods to map positron emission rate of a bio-specimen slice with high resolution. One is based on LBNL scientific charge coupled device (CCD) and the other two are based on conventional CCDs. High conversion efficiency (100k e-h pairs / 0.5 MeV positron) and low dark current (1.75 × 10(-4) e-/pix/sec) can be achieved using the LBNL CCD. The theoretical calculations and preliminary experiments show that an 86 μm spatial resolution can be achieved when imaging a 100 μm thick tissue soaked with (18)F which produce higher energy positron. The main disadvantage of the LBNL CCD we tested is that a very low operating temperature is required to eliminate dark current. This dramatically increases the system cost. In addition, the integration time of the CCD needs to be short enough to avoid overlapping of the positron trajectories. Conventional CCDs have lower conversion efficiency (2k e-h pairs / 0.5 MeV positron) and higher dark current (200 e-/pix/sec), but are more cost-efficient and the requirement for the readout frequency is much lower. The conversion efficiency of the conventional CCD imager can be improved by 17 times by inserting a 100 μm layer of phosphor between the sample and the imager. However, the light emitted from the phosphor screen will be ~100 μm diameter, which severely degrades the spatial resolution. A high readout frequency is also required to avoid the overlapping. The CCD systems designed in this study will be used to map positron emission rate of bio-specimens such as cancerous tissues acquired in regular biopsy procedure. They can also be used to corroborate tracer kinetic modeling at a cellular level.

Published
2011
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