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1. The Positive Predictive Value of Pediatric Stroke Diagnoses in Administrative Data: A Retrospective Validation Study

Author

Bindslev JB, Johnsen SP, Hansen K, Valentin JB, Hoei-Hansen CE, and Truelsen T

Subjects
positive predictive value, stroke diagnosis, stroke definition, children, interrater reliability, danish national registry of patients, Infectious and parasitic diseases, RC109-216
Abstract

Julie Brix Bindslev,1,2 Soeren Paaske Johnsen,3 Klaus Hansen,1,4 Jan Brink Valentin,3 Christina Engel Hoei-Hansen,2,4 Thomas Truelsen1,4 1Department of Neurology, University Hospital of Copenhagen, Rigshospitalet, Copenhagen, Denmark; 2Department of Pediatrics, University Hospital of Copenhagen, Rigshospitalet, Copenhagen, Denmark; 3Danish Center for Clinical Health Services Research, Department of Clinical Medicine, Aalborg University, Aalborg, Denmark; 4Department of Clinical Medicine, University of Copenhagen, Copenhagen, DenmarkCorrespondence: Julie Brix Bindslev, Department of Neurology, University Hospital of Copenhagen, Rigshospitalet, Blegdamsvej 9, Copenhagen, 2100, Denmark, Tel +45 29 92 89 10, Email JBIN0007@regionh.dkBackground: This retrospective cohort study aimed to examine the positive predictive value (PPV) of pediatric stroke diagnoses in the Danish National Registry of Patients (DNRP) and the impact of different stroke definitions on the PPV.Methods: We included children registered with a stroke or stroke-related diagnosis in the DNRP between January 2017 through December 2020. Two assessors reviewed medical records and validated cases according to the American Heart and American Stroke Association (AHA/ASA) stroke definition. The level of interrater agreement was examined using kappa statistics. Validation by the AHA/ASA definition was compared with validation according to the definition in the International Classification of Disease 11th version (ICD-11) and the World Health Organization’s definition.Results: Stroke was confirmed in 120 of 309 included children, yielding an overall PPV of 0.39 (95% CI: 0.33– 0.45). PPV varied across stroke subtypes from 0.83 (95% CI: 0.71– 0.92) for ischemic stroke (AIS), 0.57 (95% CI: 0.37– 0.76) for unspecified stroke, 0.42 (95% CI: 0.33– 0.52) for intracerebral hemorrhage (ICH) to 0.31 (95% CI: 0.55– 0.98) and 0.07 (95% CI: 0.01– 0.22) for cerebral venous thrombosis and subarachnoid hemorrhage (SAH), respectively. Most non-confirmed ICH and SAH diagnoses were in children with traumatic intracranial hemorrhages (36 and 66% respectively). Among 70 confirmed AIS cases, 25 (36%) were identified in non-AIS code groups. PPV varied significantly across stroke definitions with the highest for the AHA/ASA definition (PPV = 0.39, 95% CI: 0.34– 0.45) and the lowest for the WHO definition (PPV = 0.29, 95% CI: 0.24– 0.34). Correspondingly, the incidence of pediatric AIS per 100.000 person-years changed from 1.5 for the AHA/ASA definition to 1.2 for ICD-11 and 1.0 for the WHO-definition. The overall interrater agreement was considered excellent (κ=0.85).Conclusion: After validation, stroke was confirmed in only half of the children registered in the DNRP with a stroke-specific diagnosis. Non-validated administrative data should be used with caution in pediatric stroke research. Pediatric stroke incidence rates may vary markedly depending on which stroke definition is used.Keywords: positive predictive value, stroke diagnosis, stroke definition, children, interrater reliability, Danish National Registry of Patients

Published
2023

2. Monolithic MHz-frame rate digital SiPM-IC with sub-100 ps precision and 70$~\mu$m pixel pitch

Author

Diehl, I., Hansen, K., Vanat, T., Vignola, G., Feindt, F., Rastorguev, D., and Spannagel, S.

Subjects
Physics - Instrumentation and Detectors
Abstract

This paper presents the design and characterization of a monolithic integrated circuit (IC) including digital silicon photomultipliers (dSiPMs) arranged in a 32$~\times~$32 pixel matrix at 70$~\mu$m pitch. The IC provides per-quadrant time stamping and hit-map readout, and is fabricated in a standard 150-nm CMOS technology. Each dSiPM pixel consists of four single-photon avalanche diodes (SPADs) sharing a quenching and subsequent processing circuitry and has a fill factor of 30$~\%$. A sub-100$~$ps precision, 12-bit time-to-digital converter (TDC) provides timestamps per quadrant with an acquisition rate of 3$~$MHz. Together with the hit map, the total sustained data throughput of the IC amounts to 4$~$Gbps. Measurements obtained in a dark, temperature-stable environment as well as by using a pulsed laser environment show the full dSiPM-IC functionality. The dark-count rate (DCR) as function of the overvoltage and temperature, the TDC resolution, differential and integral nonlinearity (DNL/INL) as well as the propagation-delay variations across the matrix are presented. With aid of additional peripheral test structures, the main building blocks are characterized and key parameters are presented., Comment: 16 pages, 13 figures, 1 table

Published
2023

4. A meta-database comparison from various European Research and Monitoring Networks dedicated to forest sites

Author

Danielewska A, Clarke N, Olejnik J, Hansen K, Vries W, Lundin L, Tuovinen J, Fischer R, Urbaniak M, and Paoletti E

Subjects
Research and Monitoring Network, Meta-database, Forest, Monitoring, Forestry, SD1-669.5
Abstract

Of a wide variety of international forest research and monitoring networks, several networks are dedicated to the effects of climate change on forests, while the effects of anthropogenic pollutants on forests have been a major area for both monitoring and research for decades. The large amounts of data already obtained within existing monitoring programmes and large-scale international projects can be used to increase understanding of the state and potential of forest mitigation and adaptation to climate change in a polluted environment, and a major challenge now is to evaluate and integrate the presently available databases. We present a meta-database with the main goal to highlight available data and integrate the information about research and monitoring of selected European Research and Monitoring Networks (ERMNs). Depending on the selected ERMNs, the list of variables and the measurement units differ widely in the databases. As a result, activities related to the identification, evaluation and integration of the presently available databases are important for the scientific community. Furthermore, and equally important, the recognition of current knowledge gaps and future needed research is made easier. This analysis suggests that: ground-level ozone is under-investigated, although it is one of the pollutants of greatest concern to forests; in addition to CO2, long-term other greenhouse gasses (GHG) flux measurements should be carried out; there is still a need of improving links between monitoring of atmospheric changes and impacts on forests; research-oriented manipulative experiments in the forests are missing.

Published
2013
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8. Incretin mimetics: a novel therapeutic option for patients with type 2 diabetes – a review

Author

Knop FK and Hansen K

Subjects
Glucagon-like peptide-1 (GLP-1), exenatide, liraglutide, type 2 diabetes., Specialties of internal medicine, RC581-951
Abstract

Katrine B Hansen1, Tina Vilsbøll2, Filip K Knop21Department of Clinical Physiology, Glostrup Hospital, University of Copenhagen, Denmark; 2Diabetes Research Division, Department of Internal Medicine F, Gentofte Hospital, University of Copenhagen, DenmarkAbstract: Type 2 diabetes mellitus is a metabolic disease associated with low quality of life and early death. The goal in diabetes treatment is to prevent these outcomes by tight glycemic control and minimizing vascular risk factors. So far, even intensified combination regimen with the traditional antidiabetes agents have failed to obtain these goals. Incretin mimetics are a new class of antidiabetes drugs which involve modulation of the incretin system. They bind to and activate glucagon-like peptide-1 (GLP-1) receptors on pancreatic beta-cells following which insulin secretion and synthesis are initiated. Since the compounds have no insulinotropic activity at lower glucose concentrations the risk of hypoglycemia – a well-known shortcoming of existing antidiabetes treatments – is low. Additionally, incretin mimetics have been shown to be associated with beneficial effects on cardiovascular risk factors such as weight loss, decrease in blood pressure and changes in lipid profile. Current clinical data on the two available incretin mimetics, exenatide and liraglutide, are evaluated in this review, focusing on pharmacology, efficacy, safety and tolerability. The review is built on a systematic PubMed and Medline search for publications with the key words GLP-1 receptor agonist, exenatide, liraglutide and type 2 diabetes mellitus up to January 2009.Keywords: glucagon-like peptide-1 (GLP-1), exenatide, liraglutide, type 2 diabetes

Published
2010

9. Shape fluctuations and radiation from thermally excited electronic states of boron clusters

Author

Höltzl, T., Ferrari, P., Janssens, E., and Hansen, K.

Subjects
Physics - Atomic and Molecular Clusters, Physics - Chemical Physics
Abstract

The effect of thermal shape fluctuations on the recurrent fluorescence of boron cluster cations, B$_N^+$ ($N=9-14$), has been investigated numerically, with a special emphasis on B$_{13}^+$. For this cluster, the electronic structures of the ground state and the four lowest electronically excited states were calculated using time-dependent density functional theory, and sampled on molecular dynamics trajectories of the cluster calculated at an experimentally relevant excitation energy. The sampled optical transition matrix elements for B$_{13}^+$ allowed to construct its emission spectrum from the thermally populated electronically excited states. The spectrum was found to be broad, reaching down to at least 0.85 eV. This contrasts strongly with the static picture, where the lowest electronic transition happens at 2.3 eV. The low-lying electronic excitations produce a strong increase in the rates of recurrent fluorescence, calculated to peak at $4.6 \times 10^{4}$ s$^{-1}$, with a time-average of $8 \times 10^{3}$ s$^{-1}$. The average value is one order of magnitude higher than the static result, approaching the measured radiation rate. Similar results were found for the other cluster sizes. Furthermore, the radiationless crossing between the ground-state and the first electronic excited state surfaces of B$_{13}^+$ was calculated, found to be very fast compared to experimental time scales, justifying the thermal population assumption., Comment: 9 pages, 6 figures

Published
2022
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10. The COHERENT Experimental Program

Author

Akimov, D., Alawabdeh, S., An, P., Arteaga, A., Awe, C., Barbeau, P. S., Barry, C., Becker, B., Belov, V., Bernardi, I., Blackston, M. A., Blokland, L., Bock, C., Bodur, B., Bolozdynya, A., Bouabid, R., Bracho, A., Browning, J., Cabrera-Palmer, B., Chen, N., Chernyak, D., Conley, E., Daughhetee, J., Daughtry, J., Day, E., Coello, M. del Valle, Detwiler, J., Ding, K., Durand, M. R., Efremenko, Y., Elliott, S. R., Fabris, L., Febbraro, M., Fox, W., Galambos, J., Rosso, A. Gallo, Galindo-Uribarri, A., Gilbert, C., Green, M. P., Hansen, K. R., Harris, B., Heath, M. R., Hedges, S., Henderson, R., Hoang, D., Hughes, C., Hughes, M., Iverson, E., Jairam, P., Johnson, B. A., Johnson, T., Kaufman, L., Khromov, A., Konovalov, A., Koros, J., Kozlova, E., Kumpan, A., Li, L., Librande, J. T., Link, J. M., Liu, J., Major, A., Mann, K., Markoff, D. M., Mastroberti, J., Mattingly, J., McGoldrick, O., McIntyre, M., Melikyan, Y. A., Mishra, M., Mueller, P. E., Newby, J., Parno, D. S., Penne, A., Penttila, S. I., Pershey, D., Prior, C., Radford, D., Rahman, F., Rapp, R., Ray, H., Raybern, J., Razuvaeva, O., Reyna, D., Rich, G. C., Rimal, D., Ross, J., Rouzky, A., Rudik, D., Runge, J., Salvat, D. J., Salyapongse, A. M., Sander, J., Scholberg, K., Siehien, P., Shakirov, A., Simakov, G., Sinev, G., Snow, W. M., Sosnovstsev, V., Steele, J., Hjelmstad, A. Strasbaugh, Subedi, T., Suh, B., Tayloe, R., Tellez-Giron-Flores, K., Thornton, R. T., Tolstukhin, I., Trotter, S., Tsai, F., Tsai, Y. -T., Ujah, E., Vanderwerp, J., van Nieuwenhuizen, E., Varner, R. L., Vasquez, S., Virtue, C. J., Visser, G., Walkup, K., Wang, J., Ward, E. M., Wiseman, C., Wongjirad, T., Wu, D., Yang, J., Yang, Y., Yen, Y. -R., Yoo, J., Yu, C. -H., Zettlemoyer, J., and Zhang, S.

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

The COHERENT experiment located in Neutrino Alley at the Spallation Neutron Source (SNS), Oak Ridge National Laboratory (ORNL), has made the world's first two measurements of coherent elastic neutrino-nucleus scattering (CEvNS), on CsI and argon, using neutrinos produced at the SNS. The COHERENT collaboration continues to pursue CEvNS measurements on various targets as well as additional studies of inelastic neutrino-nucleus interactions, searches for accelerator-produced dark matter (DM) and physics beyond the Standard Model, using the uniquely high-quality and high-intensity neutrino source available at the SNS. This white paper describes primarily COHERENT's ongoing and near-future program at the SNS First Target Station (FTS). Opportunities enabled by the SNS Second Target Station (STS) for the study of neutrino physics and development of novel detector technologies are elaborated in a separate white paper., Comment: 38 papers, 24 figures; Snowmass contribution

Published
2022

11. Threshold π− production on the deuteron

Author

Strandberg B., Annand J. R. M., Briscoe W., Feldman G., Fissum K., Hansen K., Isaksson L., Myers L., and O’Reilly G. V.

Subjects
Physics, QC1-999
Abstract

An experiment that aims to measure the π− photoproduction cross-section σ(E) on the deuteron γ + 2H → π− + 2p near threshold is discussed. The main concepts of the experimental technique are presented alongside some preliminary signals.

Published
2016
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14. DESIREE: Physics with cold stored ion beams

Author

Thomas R.D., Schmidt H.T., Gatchell M., Rosén S., Reinhed P., Löfgren P., Brännholm L., Blom M., Björkhage M., Bäckström E., Alexander J.D., Leontein S., Hanstorp D., Zettergren H., Kaminska M., Nascimento R., Liljeby L., Källberg A., Simonsson A., Hellberg F., Mannervik S., Larsson M., Geppert W.D., Rensfelt K.G., Paál A., Masuda M., Halldén P., Andler G., Stockett M.H., Chen T., Källersjö G., Weimer J., Hansen K., Hartman H., and Cederquist H.

Subjects
Physics, QC1-999
Abstract

Here we will briefly describe the commissioning of the Double ElectroStatic Ion Ring ExpEriment (DESIREE) facility at Stockholm University, Sweden. This device uses purely electrostatic focussing and deflection elements and allows ion beams of opposite charge to be confined under extreme high vacuum and cryogenic conditions in separate “rings” and then merged over a common straight section. This apparatus allows for studies of interactions between cations and anions at very low and well-defined centre-of-mass energies (down to a few meV) and at very low internal temperatures (down to a few K).

Published
2015
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20. Development of a $^{83\mathrm{m}}$Kr source for the calibration of the CENNS-10 Liquid Argon Detector

Author

COHERENT Collaboration, Akimov, D., An, P., Awe, C., Barbeau, P. S., Becker, B., Belov, V., Bernardi, I., Blackston, M. A., Blokland, L., Bolozdynya, A., Cabrera-Palmer, B., Chen, N., Chernyak, D., Conley, E., Daughhetee, J., Coello, M. del Valle, Detwiler, J. A., Durand, M. R., Efremenko, Y., Elliott, S. R., Fabris, L., Febbraro, M., Fox, W., Galindo-Uribarri, A., Rosso, A. Gallo, Green, M. P., Hansen, K. S., Heath, M. R., Hedges, S., Hughes, M., Johnson, T., Khromov, A., Konovalov, A., Kozlova, E., Kumpan, A., Li, L., Librande, J. T., Link, J. M., Liu, J., Mann, K., Markoff, D. M., McGoldrick, O., Mueller, P. E., Newby, J., Parno, D. S., Pentilla, S., Pershey, D., Radford, D., Rapp, R., Ray, H., Raybern, J., Razuvaeva, O., Reyna, D., Rich, G. C., Rudik, D., Runge, J., Salvat, D. J., Scholberg, K., Shakirov, A., Simakov, G., Snow, W. M., Sosnovtsev, V., Suh, B., Tayloe, R., Tellez-Giron-Flores, K., Thornton, R. T., Tolstukhin, I., Vanderwerp, J., Varner, R. L., Venkataraman, R., Virtue, C. J., Visser, G., Wiseman, C., Wongjirad, T., Yang, J., Yen, Y. -R., Yoo, J., Yu, C. -H., and Zettlemoyer, J.

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

We report on the preparation of and calibration measurements with a $^{83\mathrm{m}}$Kr source for the CENNS-10 liquid argon detector. $^{83\mathrm{m}}$Kr atoms generated in the decay of a $^{83}$Rb source were introduced into the detector via injection into the Ar circulation loop. Scintillation light arising from the 9.4 keV and 32.1 keV conversion electrons in the decay of $^{83\mathrm{m}}$Kr in the detector volume were then observed. This calibration source allows the characterization of the low-energy response of the CENNS-10 detector and is applicable to other low-energy-threshold detectors. The energy resolution of the detector was measured to be 9$\%$ at the total $^{83\mathrm{m}}$Kr decay energy of 41.5 keV. We performed an analysis to separately calibrate the detector using the two conversion electrons at 9.4 keV and 32.1 keV, Comment: v2: As accepted to JINST

Published
2020
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21. COHERENT Collaboration data release from the first detection of coherent elastic neutrino-nucleus scattering on argon

Author

COHERENT Collaboration, Akimov, D., Albert, J. B., An, P., Awe, C., Barbeau, P. S., Becker, B., Belov, V., Blackston, M. A., Blokland, L., Bolozdynya, A., Cabrera-Palmer, B., Chen, N., Chernyak, D., Conley, E., Cooper, R. L., Daughhetee, J., Coello, M. del Valle, Detwiler, J. A., Durand, M. R., Efremenko, Y., Elliott, S. R., Fabris, L., Febbraro, M., Fox, W., Galindo-Uribarri, A., Green, M. P., Hansen, K. S., Heath, M. R., Hedges, S., Hughes, M., Johnson, T., Kaemingk, M., Kaufman, L. J., Khromov, A., Konovalov, A., Kozlova, E., Kumpan, A., Li, L., Librande, J. T., Link, J. M., Liu, J., Mann, K., Markoff, D. M., McGoldrick, O., Moreno, H., Mueller, P. E., Newby, J., Parno, D. S., Penttila, S., Pershey, D., Radford, D., Rapp, R., Ray, H., Raybern, J., Razuvaeva, O., Reyna, D., Rich, G. C., Rudik, D., Runge, J., Salvat, D. J., Scholberg, K., Shakirov, A., Simakov, G., Sinev, G., Snow, W. M., Sosnovtsev, V., Suh, B., Tayloe, R., Tellez-Giron-Flores, K., Thornton, R. T., Tolstukhin, I., Vanderwerp, J., Varner, R. L., Virtue, C. J., Visser, G., Wiseman, C., Wongjirad, T., Yang, J., Yen, Y. -R., Yoo, J., Yu, C. -H., and Zettlemoyer, J.

Subjects
Nuclear Experiment, High Energy Physics - Experiment
Abstract

Release of COHERENT collaboration data from the first detection of coherent elastic neutrino-nucleus scattering (CEvNS) on argon. This release corresponds with the results of "Analysis A" published in Akimov et al., arXiv:2003.10630 [nucl-ex]. Data is shared in a binned, text-based format representing both "signal" and "backgrounds" along with associated uncertainties such that the included data can be used to perform independent analyses. This document describes the contents of the data release as well as guidance on the use of the data. Included example code in C++ (ROOT) and Python show one possible use of the included data., Comment: Update document with arXiv ID number in requested citation

Published
2020
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22. First Measurement of Coherent Elastic Neutrino-Nucleus Scattering on Argon

Author

COHERENT Collaboration, Akimov, D., Albert, J. B., An, P., Awe, C., Barbeau, P. S., Becker, B., Belov, V., Blackston, M. A., Blokland, L., Bolozdynya, A., Cabrera-Palmer, B., Chen, N., Chernyak, D., Conley, E., Cooper, R. L., Daughhetee, J., Coello, M. del Valle, Detwiler, J. A., Durand, M. R., Efremenko, Y., Elliott, S. R., Fabris, L., Febbraro, M., Fox, W., Galindo-Uribarri, A., Green, M. P., Hansen, K. S., Heath, M. R., Hedges, S., Hughes, M., Johnson, T., Kaemingk, M., Kaufman, L. J., Khromov, A., Konovalov, A., Kozlova, E., Kumpan, A., Li, L., Librande, J. T., Link, J. M., Liu, J., Mann, K., Markoff, D. M., McGoldrick, O., Moreno, H., Mueller, P. E., Newby, J., Parno, D. S., Penttila, S., Pershey, D., Radford, D., Rapp, R., Ray, H., Raybern, J., Razuvaeva, O., Reyna, D., Rich, G. C., Rudik, D., Runge, J., Salvat, D. J., Scholberg, K., Shakirov, A., Simakov, G., Sinev, G., Snow, W. M., Sosnovtsev, V., Suh, B., Tayloe, R., Tellez-Giron-Flores, K., Thornton, R. T., Tolstukhin, I., Vanderwerp, J., Varner, R. L., Virtue, C. J., Visser, G., Wiseman, C., Wongjirad, T., Yang, J., Yen, Y. -R., Yoo, J., Yu, C. -H., and Zettlemoyer, J.

Subjects
Nuclear Experiment, High Energy Physics - Experiment
Abstract

We report the first measurement of coherent elastic neutrino-nucleus scattering (\cevns) on argon using a liquid argon detector at the Oak Ridge National Laboratory Spallation Neutron Source. Two independent analyses prefer \cevns over the background-only null hypothesis with greater than $3\sigma$ significance. The measured cross section, averaged over the incident neutrino flux, is (2.2 $\pm$ 0.7) $\times$10$^{-39}$ cm$^2$ -- consistent with the standard model prediction. The neutron-number dependence of this result, together with that from our previous measurement on CsI, confirms the existence of the \cevns process and provides improved constraints on non-standard neutrino interactions., Comment: 8 pages, 5 figures with 2 pages, 6 figures supplementary material V3: fixes to figs 3,4 V4: fix typo in table 1, V5: replaced missing appendix, V6: fix Eq 1, new fig 3, V7 final version, updated with final revisions

Published
2020
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23. Fusarium: more than a node or a foot-shaped basal cell.

Author

Crous, PW, Lombard, L, Sandoval-Denis, M, Seifert, KA, Schroers, H-J, Chaverri, P, Gené, J, Guarro, J, Hirooka, Y, Bensch, K, Kema, GHJ, Lamprecht, SC, Cai, L, Rossman, AY, Stadler, M, Summerbell, RC, Taylor, JW, Ploch, S, Visagie, CM, Yilmaz, N, Frisvad, JC, Abdel-Azeem, AM, Abdollahzadeh, J, Abdolrasouli, A, Akulov, A, Alberts, JF, Araújo, JPM, Ariyawansa, HA, Bakhshi, M, Bendiksby, M, Ben Hadj Amor, A, Bezerra, JDP, Boekhout, T, Câmara, MPS, Carbia, M, Cardinali, G, Castañeda-Ruiz, RF, Celis, A, Chaturvedi, V, Collemare, J, Croll, D, Damm, U, Decock, CA, de Vries, RP, Ezekiel, CN, Fan, XL, Fernández, NB, Gaya, E, González, CD, Gramaje, D, Groenewald, JZ, Grube, M, Guevara-Suarez, M, Gupta, VK, Guarnaccia, V, Haddaji, A, Hagen, F, Haelewaters, D, Hansen, K, Hashimoto, A, Hernández-Restrepo, M, Houbraken, J, Hubka, V, Hyde, KD, Iturriaga, T, Jeewon, R, Johnston, PR, Jurjević, Ž, Karalti, I, Korsten, L, Kuramae, EE, Kušan, I, Labuda, R, Lawrence, DP, Lee, HB, Lechat, C, Li, HY, Litovka, YA, Maharachchikumbura, SSN, Marin-Felix, Y, Matio Kemkuignou, B, Matočec, N, McTaggart, AR, Mlčoch, P, Mugnai, L, Nakashima, C, Nilsson, RH, Noumeur, SR, Pavlov, IN, Peralta, MP, Phillips, AJL, Pitt, JI, Polizzi, G, Quaedvlieg, W, Rajeshkumar, KC, Restrepo, S, Rhaiem, A, Robert, J, Robert, V, and Rodrigues, AM

Subjects
Apiognomonia platani (Lév.) L. Lombard, Atractium ciliatum Link, Atractium pallidum Bonord., Calloria tremelloides (Grev.) L. Lombard, Cephalosporium sacchari E.J. Butler, Cosmosporella cavisperma (Corda) Sand.-Den., L. Lombard & Crous, Cylindrodendrum orthosporum (Sacc. & P. Syd.) L. Lombard, Dialonectria volutella (Ellis & Everh.) L. Lombard & Sand.-Den., Fusarium aeruginosum Delacr., Fusarium agaricorum Sarrazin, Fusarium albidoviolaceum Dasz., Fusarium aleyrodis Petch, Fusarium amentorum Lacroix, Fusarium annuum Leonian, Fusarium arcuatum Berk. & M.A. Curtis, Fusarium aridum O.A. Pratt, Fusarium armeniacum (G.A. Forbes et al.) L.W. Burgess & Summerell, Fusarium arthrosporioides Sherb., Fusarium asparagi Delacr., Fusarium batatas Wollenw., Fusarium biforme Sherb., Fusarium buharicum Jacz. ex Babajan & Teterevn.-Babajan, Fusarium cactacearum Pasin. & Buzz.-Trav., Fusarium cacti-maxonii Pasin. & Buzz.-Trav., Fusarium caudatum Wollenw., Fusarium cavispermum Corda, Fusarium cepae Hanzawa, Fusarium cesatii Rabenh., Fusarium citriforme Jamal., Fusarium citrinum Wollenw., Fusarium citrulli Taubenh., Fusarium clavatum Sherb., Fusarium coccinellum Kalchbr., Fusarium cromyophthoron Sideris, Fusarium cucurbitae Taubenh., Fusarium cuneiforme Sherb., Fusarium delacroixii Sacc., Fusarium dimerum var. nectrioides Wollenw., Fusarium echinatum Sand.-Den. & G.J. Marais, Fusarium epicoccum McAlpine, Fusarium eucheliae Sartory, R. Sartory & J. Mey., Fusarium fissum Peyl, Fusarium flocciferum Corda, Fusarium gemmiperda Aderh., Fusarium genevense Dasz., Fusarium graminearum Schwabe, Fusarium graminum Corda, Fusarium heterosporioides Fautrey, Fusarium heterosporum Nees & T. Nees, Fusarium idahoanum O.A. Pratt, Fusarium juruanum Henn., Fusarium lanceolatum O.A. Pratt, Fusarium lateritium Nees, Fusarium loncheceras Sideris, Fusarium longipes Wollenw. & Reinking, Fusarium lyarnte J.L. Walsh, Sangal., L.W. Burgess, E.C.Y. Liew & Summerell, Fusarium malvacearum Taubenh., Fusarium martii f. phaseoli Burkh., Fusarium muentzii Delacr., Fusarium nigrum O.A. Pratt, Fusarium oxysporum var. asclerotium Sherb., Fusarium palczewskii Jacz., Fusarium palustre W.H. Elmer & Marra, Fusarium polymorphum Matr., Fusarium poolense Taubenh., Fusarium prieskaense G.J. Marais & Sand.-Den., Fusarium prunorum McAlpine, Fusarium pusillum Wollenw., Fusarium putrefaciens Osterw., Fusarium redolens Wollenw., Fusarium reticulatum Mont., Fusarium rhizochromatistes Sideris, Fusarium rhizophilum Corda, Fusarium rhodellum McAlpine, Fusarium roesleri Thüm., Fusarium rostratum Appel & Wollenw., Fusarium rubiginosum Appel & Wollenw., Fusarium rubrum Parav., Fusarium samoense Gehrm., Fusarium scirpi Lambotte & Fautrey, Fusarium secalis Jacz., Fusarium spinaciae Hungerf., Fusarium sporotrichioides Sherb., Fusarium stercoris Fuckel, Fusarium stilboides Wollenw., Fusarium stillatum De Not. ex Sacc., Fusarium sublunatum Reinking, Fusarium succisae Schröt. ex Sacc., Fusarium tabacivorum Delacr., Fusarium trichothecioides Wollenw., Fusarium tritici Liebman, Fusarium tuberivorum Wilcox & G.K. Link, Fusarium tumidum var. humi Reinking, Fusarium ustilaginis Kellerm. & Swingle, Fusarium viticola Thüm., Fusarium werrikimbe J.L. Walsh, L.W. Burgess, E.C.Y. Liew & B.A. Summerell, Fusarium willkommii Lindau, Fusarium xylarioides Steyaert, Fusarium zygopetali Delacr., Fusicolla meniscoidea L. Lombard & Sand.-Den., Fusicolla quarantenae J.D.P. Bezerra, Sand.-Den., Crous & Souza-Motta, Fusicolla sporellula Sand.-Den. & L. Lombard, Fusisporium andropogonis Cooke ex Thüm., Fusisporium anthophilum A. Braun, Fusisporium arundinis Corda, Fusisporium avenaceum Fr., Fusisporium clypeaster Corda, Fusisporium culmorum Wm.G. Sm., Fusisporium didymum Harting, Fusisporium elasticae Thüm., Fusisporium episphaericum Cooke & Ellis, Fusisporium flavidum Bonord., Fusisporium hordei Wm.G. Sm., Fusisporium incarnatum Roberge ex Desm., Fusisporium lolii Wm.G. Sm., Fusisporium pandani Corda, Gibberella phyllostachydicola W. Yamam., Hymenella aurea (Corda) L. Lombard, Hymenella spermogoniopsis (Jul. Müll.) L. Lombard & Sand.-Den., Luteonectria Sand.-Den., L. Lombard, Schroers & Rossman, Luteonectria albida (Rossman) Sand.-Den. & L. Lombard, Luteonectria nematophila (Nirenberg & Hagedorn) Sand.-Den. & L. Lombard, Macroconia bulbipes Crous & Sand.-Den., Macroconia phlogioides Sand.-Den. & Crous, Menispora penicillata Harz, Multi-gene phylogeny, Mycotoxins, Nectriaceae, Neocosmospora, Neocosmospora epipeda Quaedvl. & Sand.-Den., Neocosmospora floridana (T. Aoki et al.) L. Lombard & Sand.-Den., Neocosmospora merkxiana Quaedvl. & Sand.-Den., Neocosmospora neerlandica Crous & Sand.-Den., Neocosmospora nelsonii Crous & Sand.-Den., Neocosmospora obliquiseptata (T. Aoki et al.) L. Lombard & Sand.-Den., Neocosmospora pseudopisi Sand.-Den. & L. Lombard, Neocosmospora rekana (Lynn & Marinc.) L. Lombard & Sand.-Den., Neocosmospora tuaranensis (T. Aoki et al.) L. Lombard & Sand.-Den., Nothofusarium Crous, Sand.-Den. & L. Lombard, Nothofusarium devonianum L. Lombard, Crous & Sand.-Den., Novel taxa, Pathogen, Scolecofusarium L. Lombard, Sand.-Den. & Crous, Scolecofusarium ciliatum (Link) L. Lombard, Sand.-Den. & Crous, Selenosporium equiseti Corda, Selenosporium hippocastani Corda, Selenosporium sarcochroum Desm, Selenosporium urticearum Corda., Setofusarium (Nirenberg & Samuels) Crous & Sand.-Den., Setofusarium setosum (Samuels & Nirenberg) Sand.-Den. & Crous., Sphaeria sanguinea var. cicatricum Berk., Sporotrichum poae Peck., Stylonectria corniculata Gräfenhan, Crous & Sand.-Den., Stylonectria hetmanica Akulov, Crous & Sand.-Den., Taxonomy, Mycology & Parasitology, Microbiology
Abstract

Recent publications have argued that there are potentially serious consequences for researchers in recognising distinct genera in the terminal fusarioid clade of the family Nectriaceae. Thus, an alternate hypothesis, namely a very broad concept of the genus Fusarium was proposed. In doing so, however, a significant body of data that supports distinct genera in Nectriaceae based on morphology, biology, and phylogeny is disregarded. A DNA phylogeny based on 19 orthologous protein-coding genes was presented to support a very broad concept of Fusarium at the F1 node in Nectriaceae. Here, we demonstrate that re-analyses of this dataset show that all 19 genes support the F3 node that represents Fusarium sensu stricto as defined by F. sambucinum (sexual morph synonym Gibberella pulicaris). The backbone of the phylogeny is resolved by the concatenated alignment, but only six of the 19 genes fully support the F1 node, representing the broad circumscription of Fusarium. Furthermore, a re-analysis of the concatenated dataset revealed alternate topologies in different phylogenetic algorithms, highlighting the deep divergence and unresolved placement of various Nectriaceae lineages proposed as members of Fusarium. Species of Fusarium s. str. are characterised by Gibberella sexual morphs, asexual morphs with thin- or thick-walled macroconidia that have variously shaped apical and basal cells, and trichothecene mycotoxin production, which separates them from other fusarioid genera. Here we show that the Wollenweber concept of Fusarium presently accounts for 20 segregate genera with clear-cut synapomorphic traits, and that fusarioid macroconidia represent a character that has been gained or lost multiple times throughout Nectriaceae. Thus, the very broad circumscription of Fusarium is blurry and without apparent synapomorphies, and does not include all genera with fusarium-like macroconidia, which are spread throughout Nectriaceae (e.g., Cosmosporella, Macroconia, Microcera). In this study four new genera are introduced, along with 18 new species and 16 new combinations. These names convey information about relationships, morphology, and ecological preference that would otherwise be lost in a broader definition of Fusarium. To assist users to correctly identify fusarioid genera and species, we introduce a new online identification database, Fusarioid-ID, accessible at www.fusarium.org. The database comprises partial sequences from multiple genes commonly used to identify fusarioid taxa (act1, CaM, his3, rpb1, rpb2, tef1, tub2, ITS, and LSU). In this paper, we also present a nomenclator of names that have been introduced in Fusarium up to January 2021 as well as their current status, types, and diagnostic DNA barcode data. In this study, researchers from 46 countries, representing taxonomists, plant pathologists, medical mycologists, quarantine officials, regulatory agencies, and students, strongly support the application and use of a more precisely delimited Fusarium (= Gibberella) concept to accommodate taxa from the robust monophyletic node F3 on the basis of a well-defined and unique combination of morphological and biochemical features. This F3 node includes, among others, species of the F. fujikuroi, F. incarnatum-equiseti, F. oxysporum, and F. sambucinum species complexes, but not species of Bisifusarium [F. dimerum species complex (SC)], Cyanonectria (F. buxicola SC), Geejayessia (F. staphyleae SC), Neocosmospora (F. solani SC) or Rectifusarium (F. ventricosum SC). The present study represents the first step to generating a new online monograph of Fusarium and allied fusarioid genera (www.fusarium.org).

Published
2021

26. Spontaneous electron emission from hot silver dimer anions: Breakdown of the Born-Oppenheimer approximation

Author

Anderson, E. K., Schmidt-May, A. F., Najeeb, P. K., Eklund, G., Chartkunchand, K. C., Rosén, S., Larson, Å., Hansen, K., Cederquist, H., Zettergren, H., and Schmidt, H. T.

Subjects
Physics - Atomic and Molecular Clusters
Abstract

We report the first experimental evidence of spontaneous electron emission from a homonuclear dimer anion through direct measurements of $\rm{Ag}_2^- \rightarrow \rm{Ag}_2 + \rm{e}^-$ decays on milliseconds and seconds time scales. This observation is very surprising as there is no avoided crossing between adiabatic energy curves to mediate such a process. The process is weak but yet dominates the decay signal after 100 ms when ensembles of internally hot Ag$_2^-$ ions are stored in the cryogenic ion-beam storage ring, DESIREE, for 10 seconds. The electron emission process is associated with an instantaneous, very large, reduction of the vibrational energy of the dimer system. This represents a dramatic deviation from a Born-Oppenheimer description of dimer dynamics.

Published
2019
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27. Sensitivity of the COHERENT Experiment to Accelerator-Produced Dark Matter

Author

COHERENT Collaboration, Akimov, D., An, P., Awe, C., Barbeau, P. S., Becker, B., Belov, V., Blackston, M. A., Bolozdynya, A., Cabrera-Palmer, B., Chen, N., Conley, E., Cooper, R. L., Daughhetee, J., Coello, M. del Valle, Detwiler, J. A., Durand, M. R., Efremenko, Y., Elliott, S. R., Fabris, L., Febbraro, M., Fox, W., Galindo-Uribarri, A., Green, M. P., Hansen, K. S., Heath, M. R., Hedges, S., Johnson, T., Kaemingk, M., Kaufman, L. J., Khromov, A., Konovalov, A., Kozlova, E., Kumpan, A., Li, L., Librande, J. T., Link, J. M., Liu, J., Mann, K., Markoff, D. M., Moreno, H., Mueller, P. E., Newby, J., Parno, D. S., Penttila, S., Pershey, D., Radford, D., Rapp, R., Ray, H., Raybern, J., Razuvaeva, O., Reyna, D., Rich, G. C., Rudik, D., Runge, J., Salvat, D. J., Scholberg, K., Shakirov, A., Simakov, G., Sinev, G., Snow, W. M., Sosnovtsev, V., Suh, B., Tayloe, R., Tellez-Giron-Flores, K., Thornton, R. T., Tolstukhin, I., Vanderwerp, J., Varner, R. L., Virtue, C. J., Visser, G., Wiseman, C., Wongjirad, T., Yang, J., Yen, Y. -R., Yoo, J., Yu, C. -H., and Zettlemoyer, J.

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

The COHERENT experiment is well poised to test sub-GeV dark matter models using low-energy recoil detectors sensitive to coherent elastic neutrino-nucleus scattering (CEvNS) in the $\pi$-DAR neutrino beam produced by the Spallation Neutron Source. We show how a planned 750-kg liquid argon scintillation detector would place leading limits on scalar light dark matter models, over two orders of magnitude of dark matter mass, for dark matter particles produced through vector and leptophobic portals in the absence of other effects beyond the standard model. The characteristic timing structure of a $\pi$-DAR beam allows a unique opportunity for constraining systematic uncertainties on the standard model background in a time window where signal is not expected, enhancing expected sensitivity. Additionally, we discuss future prospects, further increasing the discovery potential of CEvNS detectors. Such methods would test the calculated thermal dark matter abundance for all couplings $\alpha'\leq1$ within the vector portal model over an order of magnitude of dark matter masses.

Published
2019
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28. First Constraint on Coherent Elastic Neutrino-Nucleus Scattering in Argon

Author

COHERENT Collaboration, Akimov, D., Albert, J. B., An, P., Awe, C., Barbeau, P. S., Becker, B., Belov, V., Blackston, M. A., Bolozdynya, A., Cabrera-Palmer, B., Cervantes, M., Collar, J. I., Cooper, R. L., Daughhetee, J., Coello, M. del Valle, Detwiler, J. A., D'Onofrio, M., Efremenko, Y., Erkela, E. M., Elliott, S. R., Fabris, L., Febbraro, M., Fox, W., Galindo-Uribarri, A., Green, M. P., Hansen, K. S., Heath, M. R., Hedges, S., Johnson, T., Kaemingk, M., Kaufman, L. J., Khromov, A., Konovalov, A., Kozlova, E., Kumpan, A., Li, L., Librande, J. T., Link, J. M., Liu, J., Mann, K., Markoff, D. M., Moreno, H., Mueller, P. E., Newby, J., Parno, D. S., Penttila, S., Pershey, D., Radford, D., Rapp, R., Ray, H., Raybern, J., Razuvaeva, O., Reyna, D., Rich, G. C., Rudik, D., Runge, J., Salvat, D. J., Scholberg, K., Shakirov, A., Simakov, G., Sinev, G., Snow, W. M., Sosnovtsev, V., Suh, B., Tayloe, R., Tellez-Giron-Flores, K., Thornton, R. T., Tolstukhin, I., Vanderwerp, J., Varner, R. L., Virtue, C. J., Visser, G., Wiseman, C., Wongjirad, T., Yang, J., Yen, Y. -R., Yoo, J., Yu, C. -H., and Zettlemoyer, J.

Subjects
High Energy Physics - Experiment, Nuclear Experiment
Abstract

Coherent elastic neutrino-nucleus scattering (CEvNS) is the dominant neutrino scattering channel for neutrinos of energy $E_\nu < 100$ MeV. We report a limit for this process using data collected in an engineering run of the 29 kg CENNS-10 liquid argon detector located 27.5 m from the Oak Ridge National Laboratory Spallation Neutron Source (SNS) Hg target with $4.2\times 10^{22}$ protons on target. The dataset yielded $< 7.4$ observed CEvNS events implying a cross section for the process, averaged over the SNS pion decay-at-rest flux, of $<3.4 \times 10^{-39}$ cm$^{2}$, a limit within twice the Standard Model prediction. This is the first limit on CEvNS from an argon nucleus and confirms the earlier CsI non-standard neutrino interaction constraints from the collaboration. This run demonstrated the feasibility of the ongoing experimental effort to detect CEvNS with liquid argon.

Published
2019
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29. Near-threshold $\pi^-$ photoproduction on the deuteron

Author

Strandberg, B., Fissum, K. G., Annand, J. R. M., Briscoe, W. J., Brudvik, J., Cividini, F., Clark, L., Downie, E. J., England, K., Feldman, G., Glazier, D. I., Hamilton, K., Hansen, K., Isaksson, L., Jebali, R. Al, Kovash, M. A., Kudryavtsev, A. E., Lensky, V., Lipschutz, S., Lundin, M., Meshkian, M., Middleton, D. G., Myers, L. S., O'Donnell, D., O'Rielly, G. V., Oussena, B., Preston, M. F., Schröder, B., Seitz, B., Strakovsky, I. I., Taragin, M., and Tarasov, V. E.

Subjects
Nuclear Experiment
Abstract

The first experimental investigation of the near-threshold cross section for incoherent $\pi^-$ photoproduction on the deuteron $\gamma$ d -> $\pi^-$ pp is presented. The experimental technique involved detection of the ~131 MeV gamma ray resulting from the radiative capture of photoproduced $\pi^-$ in the target. The total cross section has been measured using an unpolarized tagged-photon beam, a liquid-deuterium target, and three very large NaI(Tl) spectrometers. The data are compared to theoretical models that give insight into the elementary reaction $\gamma$ n -> $\pi^-$ p and pion-nucleon and nucleon-nucleon final-state interactions., Comment: 8 pages, 6 figures, to be submitted to Physical Review C

Published
2018
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30. Decays of excited silver cluster anions Ag$_{n}$, $n = 4$ to $7$, in DESIREE

Author

Anderson, E. K., Kamińska, M., Chartkunchand, K. C., Eklund, G., Gatchell, M., Hansen, K., Zettergren, H., Cederquist, H., and Schmidt, H. T.

Subjects
Physics - Atomic and Molecular Clusters
Abstract

Spontaneous decays of small, hot silver cluster anions Ag$_{n}$, $n=4-7$ have been studied using one of the rings of the Double ElectroStatic Ion Ring ExpEriment (DESIREE). Observation of these decays over very long time scales is possible due to the very low residual gas pressure ($\sim10^{-14}$) and cryogenic (13 K) operation of DESIREE. The yield of neutral particles from stored beams of Ag$_{6}$ and Ag$_{7}$ anions were measured for 100 milliseconds and were found to follow single power law behaviour with millisecond time scale exponential cut-offs. The Ag$_{4}$ and Ag$_{5}$ anions were stored for 60 seconds and the observed decays show two-component power law behaviors. We present calculations of the rate constants for electron detachment from, and fragmentation of Ag$_{4}$ and Ag$_{5}$. In these calculations, we assume that the internal energy distribution of the clusters are flat and with this we reproduce the early steep parts of the experimentally measured decay curves for Ag$_{4}$ and Ag$_{5}$, which extends to tens and hundreds of milliseconds, respectively. The fact that the calculations reproduce the early slopes of Ag$_{4}$ and Ag$_{5}$, which differ for the two cases, suggests that it is the changes in fragmentation rates with internal cluster energies of Ag$_{4}$ and Ag$_{5}$ rather than conditions in the ion source that determines this behavior. Comparisons with the measurements strongly suggest that the neutral particles detected in these time domains originate from Ag$_{4} \rightarrow$ Ag$_{3}+$ Ag and Ag$_{5}\rightarrow$ Ag$_{3}+$ Ag$_{2}$ fragmentation processes.

Published
2018
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31. Spontaneous decay of small copper cluster anions Cu$_n^-$, $n=3-6$ on long time scales

Author

Hansen, K., Stockett, M. H., Kaminska, M., Nascimento, R. F., Anderson, E. K., Gatchell, M., Chartkunchand, K. C., Eklund, G., Zettergren, H., Schmidt, H. T., and Cederquist, H.

Subjects
Physics - Atomic and Molecular Clusters
Abstract

We have measured the spontaneous neutral particle emission from copper cluster anions (Cu$_n^-$, $n=3-6$) stored at cryogenic temperatures in one of the electrostatic ion storage rings of the DESIREE (Double ElectroStatic Ion Ring ExpEriment) facility at Stockholm University. The measured rate of emission from the stored Cu$_3^-$ ions follows a single power law decay for about 1 ms but then decreases much more rapidly with time. The latter behavior may be due to a decrease in the density of available final states in Cu$_3$ as the excitation energies of the decaying ions approach the electron detachment threshold. The emissions from Cu$_4^-$, Cu$_5^-$ and Cu$_6^-$ are well-described by sums of two power laws that are quenched by radiative cooling of the stored ions with characteristic times between a few and hundreds of milliseconds. We relate these two-component behaviors to populations of stored ions with higher and lower angular momenta. In a separate experiment, we studied the laser-induced decay of Cu$_6^-$ ions that were excited by 1.13 eV or 1.45 eV photons after 46 milliseconds of storage.

Published
2018
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32. First storage of ion beams in the Double Electrostatic Ion-Ring Experiment - DESIREE

Author

Schmidt, H. T., Thomas, R. D., Gatchell, M., Rosén, S., Reinhed, P., Löfgren, P., Brännholm, L., Blom, M., Björkhage, M., Bäckström, E., Alexander, J. D., Leontein, S., Hanstorp, D., Zettergren, H., Liljeby, L., Källberg, A., Simonsson, A., Hellberg, F., Mannervik, S., Larsson, M., Geppert, W. D., Rensfelt, K. G., Danared, H., Paál, A., Masuda, M., Halldén, P., Andler, G., Stockett, M. H., Chen, T., Källersjö, G., Weimer, J., Hansen, K., Hartman, H., and Cederquist, H.

Subjects
Physics - Accelerator Physics, Physics - Atomic Physics, Physics - Instrumentation and Detectors
Abstract

We report on the first storage of ion beams in the Double ElectroStatic Ion Ring ExpEriment; DESIREE, at Stockholm University. We have produced beams of atomic carbon anions and small carbon anion molecules (C$_n^-$, $n=1,2,3,4$) in a sputter ion source. The ion beams were accelerated to 10 keV kinetic energy and stored in an electrostatic ion storage ring enclosed in a vacuum chamber at 13 K. For 10 keV C$_2^-$ molecular anions we measure the residual-gas limited beam storage lifetime to be 448 s $\pm$ 18 s with two independent detector systems. Using the measured storage lifetimes we estimate that the residual gas pressure is in the 10$^{-14}$ mbar range. When high current ion beams are injected, the number of stored particles does not follow a single exponential decay law as would be expected for stored particles lost solely due to electron detachment in collision with the residual-gas. Instead, we observe a faster initial decay rate, which we ascribe to the effect of the space charge of the ion beam on the storage capacity. %The latter effect becomes insignificant after longer storage times of typically 100-150 seconds and we then observe a constant decay rate due to residual-gas collisions.

Published
2018
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33. Compton Scattering from the Deuteron above Pion-Production Threshold

Author

Strandberg, B., Annand, J. R. M., Briscoe, W., Brudvik, J., Cividini, F., Clark, L., Downie, E. J., England, K., Feldman, G., Fissum, K. G., Glazier, D. I., Hamilton, K., Hansen, K., Isaksson, L., Jebali, R. Al, Kovash, M. A., Lipschutz, S., Lundin, M., Meshkian, M., Middleton, D. G., Myers, L. S., O'Donnell, D., O'Rielly, G., Oussena, B., Preston, M. F., Schröder, B., Seitz, B., Strakovsky, I., and Taragin, M.

Subjects
Nuclear Experiment
Abstract

The electromagnetic polarizabilities of the nucleon are fundamental nucleon-structure observables that characterize its response to external electromagnetic fields. The neutron polarizabilities can be accessed from Compton-scattering data on light nuclear targets. Recent measurements of the differential cross section for Compton scattering on the deuteron below the pion-production threshold have decreased the uncertainties in the neutron polarizabilities, yet the proton polarizabilities remain known substantially more accurately. As the sensitivity of the cross section to the polarizabilities increases with incident photon energy, measurements above the pion threshold may offer a way for an improved determination of the neutron polarizabilities. In this article, the first measurement of the cross section for Compton scattering on the deuteron above the pion-production threshold is presented., Comment: 6 pages, 4 figures, to be submitted to Physical Review C Rapid Communications

Published
2018
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34. Hall Effect in the coma of 67P/Churyumov-Gerasimenko

Author

Huang, Z., Toth, G., Gombosi, T. I., Jia, X., Combi, M. R., Hansen, K. C., Fougere, N., Shou, Y., Tenishev, V., Altwegg, K., and Rubin, M.

Subjects
Astrophysics - Earth and Planetary Astrophysics, Physics - Space Physics
Abstract

Magnetohydrodynamics simulations have been carried out in studying the solar wind and cometary plasma interactions for decades. Various plasma boundaries have been simulated and compared well with observations for comet 1P/Halley. The Rosetta mission, which studies comet 67P/Churyumov-Gerasimenko, challenges our understanding of the solar wind and comet interactions. The Rosetta Plasma Consortium observed regions of very weak magnetic field outside the predicted diamagnetic cavity. In this paper, we simulate the inner coma with the Hall magnetohydrodynamics equations and show that the Hall effect is important in the inner coma environment. The magnetic field topology becomes complex and magnetic reconnection occurs on the dayside when the Hall effect is taken into account. The magnetic reconnection on the dayside can generate weak magnetic filed regions outside the global diamagnetic cavity, which may explain the Rosetta Plasma Consortium observations. We conclude that the substantial change in the inner coma environment is due to the fact that the ion inertial length (or gyro radius) is not much smaller than the size of the diamagnetic cavity., Comment: 23 pages, 6 figurs

Published
2018
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35. Explosive fragmentation of additively manufactured stainless steel.

Author

Callahan, M., Sun, D., Linne, M. A., Wu, A. S., Campbell, G. H., Friedman, B., Rodriguez, J., Burke, S., Lodes, A., Hansen, K., Mickelson, K., Wraith, R., Nicolino, J. J., and Park, H.-S.

Subjects
STAINLESS steel, STEEL manufacture, DOPPLER velocimetry, STRAINS & stresses (Mechanics), STRESS concentration
Abstract

Properties of fragmentation from an explosively driven 316L stainless steel spherical shell section fabricated by a laser powder bed additive manufacturing process with minimal surface finishing are investigated. This shell is driven by an insensitive high explosive, resulting in high strain rate deformation (>8 × 103 s−1) and failure of the stainless steel. Photonic Doppler velocimetry measures the expansion rate; dynamic radiography and high-speed imaging capture the fracture behavior of the stainless steel. The fracture response of the additively manufactured stainless steel shell is compared to published experimental results on additively manufactured 316L stainless steel and conventionally manufactured wrought 316L and 304 stainless steel shell fragmentation. Despite preferred crack orientation, suggesting the influence of surface grooves on fracture time, fragment size is identical to that measured in a similar experiment on wrought 304 stainless steel. Further analysis indicates that the 316L additively manufactured stainless steel shell exhibits comparable spall strength and fragmentation toughness to conventionally manufactured stainless steel yet lower failure strain due to surface stress concentrations. [ABSTRACT FROM AUTHOR]

Published
2023
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36. Test Beam Performance Measurements for the Phase I Upgrade of the CMS Pixel Detector

Author

Dragicevic, M., Friedl, M., Hrubec, J., Steininger, H., Gädda, A., Härkönen, J., Lampén, T., Luukka, P., Peltola, T., Tuominen, E., Tuovinen, E., Winkler, A., Eerola, P., Tuuva, T., Baulieu, G., Boudoul, G., Caponetto, L., Combaret, C., Contardo, D., Dupasquier, T., Gallbit, G., Lumb, N., Mirabito, L., Perries, S., Donckt, M. Vander, Viret, S., Bonnin, C., Charles, L., Gross, L., Hosselet, J., Tromson, D., Feld, L., Karpinski, W., Klein, K., Lipinski, M., Pierschel, G., Preuten, M., Rauch, M., Wlochal, M., Aldaya, M., Asawatangtrakuldee, C., Beernaert, K., Bertsche, D., Contreras-Campana, C., Eckerlin, G., Eckstein, D., Eichhorn, T., Gallo, E., Garcia, J. Garay, Hansen, K., Haranko, M., Harb, A., Hauk, J., Keaveney, J., Kalogeropoulos, A., Kleinwort, C., Lohmann, W., Mankel, R., Maser, H., Mittag, G., Muhl, C., Mussgiller, A., Pitzl, D., Reichelt, O., Savitskyi, M., Schütze, P., Sola, V., Spannagel, S., Walsh, R., Zuber, A., Biskop, H., Buhmann, P., Centis-Vignali, M., Garutti, E., Haller, J., Hoffmann, M., Klanner, R., Lapsien, T., Matysek, M., Perieanu, A., Scharf, Ch., Schleper, P., Schmidt, A., Schwandt, J., Sonneveld, J., Steinbrück, G., Vormwald, B., Wellhausen, J., Abbas, M., Amstutz, C., Barvich, T., Barth, Ch., Boegelspacher, F., De Boer, W., Butz, E., Casele, M., Colombo, F., Dierlamm, A., Freund, B., Hartmann, F., Heindl, S., Husemann, U., Kornmeyer, A., Kudella, S., Muller, Th., Simonis, H. J., Steck, P., Weber, M., Weiler, Th., Kiss, T., Siklér, F., Tölyhi, T., Veszprémi, V., Cariola, P., Creanza, D., De Palma, M., De Robertis, G., Fiore, L., Franco, M., Loddo, F., Sala, G., Silvestris, L., Maggi, G., My, S., Selvaggi, G., Albergo, S., Cappello, G., Costa, S., Di Mattia, A., Giordano, F., Potenza, R., Saizu, M. A., Tricomi, A., Tuve, C., Focardi, E., Dinardo, M. E., Fiorendi, S., Gennai, S., Malvezzi, S., Manzoni, R. A., Menasce, D., Moroni, L., Pedrini, D., Azzi, P., Bacchetta, N., Bisello, D., Dall'Osso, M., Pozzobon, N., Tosi, M., Solestizi, L. Alunni, Biasini, M., Bilei, G. M., Cecchi, C., Checcucci, B., Ciangottini, D., Fanò, L., Gentsos, C., Ionica, M., Leonardi, R., Manoni, E., Mantovani, G., Marconi, S., Mariani, V., Menichelli, M., Modak, A., Morozzi, A., Moscatelli, F., Passeri, D., Placidi, P., Postolache, V., Rossi, A., Saha, A., Santocchia, A., Storchi, L., Spiga, D., Androsov, K., Azzurri, P., Bagliesi, G., Basti, A., Boccali, T., Borrello, L., Bosi, F., Castaldi, R., Ceccanti, M., Ciocci, M. A., Dell'Orso, R., Donato, S., Fedi, G., Giassi, A., Grippo, M. T., Ligabue, F., Magazzu, G., Mammini, P., Mariani, F., Mazzoni, E., Messineo, A., Moggi, A., Morsani, F., Palla, F., Palmonari, F., Profeti, A., Raffaelli, F., Ragonesi, A., Rizzi, A., Soldani, A., Spagnolo, P., Tenchini, R., Tonelli, G., Venturi, A., Verdini, P. G., Abbaneo, D., Ahmed, I., Albert, E., Auzinger, G., Berruti, G., Bonnaud, J., Daguin, J., D'Auria, A., Detraz, S., Dondelewski, O., Engegaard, B., Faccio, F., Frank, N., Gill, K., Honma, A., Kornmayer, A., Labaza, A., Manolescu, F., McGill, I., Mersi, S., Michelis, S., Onnela, A., Ostrega, M., Pavis, S., Peisert, A., Pernot, J. -F., Petagna, P., Postema, H., Rapacz, K., Sigaud, C., Tropea, P., Troska, J., Tsirou, A., Vasey, F., Verlaat, B., Vichoudis, P., Zwalinski, L., Bachmair, F., Becker, R., di Calafiori, D., Casal, B., Berger, P., Djambazov, L., Donega, M., Grab, C., Hits, D., Hoss, J., Kasieczka, G., Lustermann, W., Mangano, B., Marionneau, M., del Arbol, P. Martinez Ruiz, Masciovecchio, M., Meinhard, M., Perozzi, L., Roeser, U., Starodumov, A., Tavolaro, V., Wallny, R., Zhu, D., Bösiger, K., Caminada, L., Canelli, F., Chiochia, V., de Cosa, A., Galloni, C., Hreus, T., Kilminster, B., Lange, C., Maier, R., Ngadiuba, J., Pinna, D., Robmann, P., Taroni, S., Yang, Y., Bertl, W., Deiters, K., Erdmann, W., Horisberger, R., Kaestli, H. -C., Kotlinski, D., Langenegger, U., Meier, B., Rohe, T., Streuli, S., Chen, P. -H., Dietz, C., Fiori, F., Grundler, U., Hou, W. -S., Lu, R. -S., Moya, M., Tsai, J. -F., Tzeng, Y. M., Cussans, D., Goldstein, J., Grimes, M., Newbold, D., Hobson, P., Reid, I. D., Bainbridge, R., Dauncey, P., Hall, G., James, T., Magnan, A. -M., Pesaresi, M., Raymond, D. M., Uchida, K., Durkin, T., Harder, K., Shepherd-Themistocleous, C., Chertok, M., Conway, J., Conway, R., Flores, C., Lander, R., Pellett, D., Ricci-Tam, F., Squires, M., Thomson, J., Yohay, R., Burt, K., Ellison, J., Hanson, G., Olmedo, M., Si, W., Yates, B. R., Dominguez, A., Bartek, R., Bentele, B., Cumalat, J. P., Ford, W. T., Jensen, F., Johnson, A., Krohn, M., Leontsinis, S., Mulholland, T., Stenson, K., Wagner, S. R., Apresyan, A., Bolla, G., Burkett, K., Butler, J. N., Canepa, A., Cheung, H. W. K., Christian, D., Cooper, W. E., Deptuch, G., Derylo, G., Gingu, C., Grünendahl, S., Hasegawa, S., Hoff, J., Howell, J., Hrycyk, M., Jindariani, S., Johnson, M., Kahlid, F., Kwan, S., Lei, C. M., Lipton, R., De Sá, R. Lopes, Liu, T., Los, S., Matulik, M., Merkel, P., Nahn, S., Prosser, A., Rivera, R., Schneider, B., Sellberg, G., Shenai, A., Siehl, K., Spiegel, L., Tran, N., Uplegger, L., Voirin, E., Berry, D. R., Chen, X., Ennesser, L., Evdokimov, A., Gerber, C. E., Makauda, S., Mills, C., Gonzalez, I. D. Sandoval, Alimena, J., Antonelli, L. J., Francis, B., Hart, A., Hill, C. S., Parashar, N., Stupak, J., Bortoletto, D., Bubna, M., Hinton, N., Jones, M., Miller, D. H., Shi, X., Baringer, P., Bean, A., Khalil, S., Kropivnitskaya, A., Majumder, D., Schmitz, E., Wilson, G., Ivanov, A., Mendis, R., Mitchell, T., Skhirtladze, N., Taylor, R., Anderson, I., Fehling, D., Gritsan, A., Maksimovic, P., Martin, C., Nash, K., Osherson, M., Swartz, M., Xiao, M., Acosta, J. G., Cremaldi, L. M., Oliveros, S., Perera, L., Summers, D., Bloom, K., Claes, D. R., Fangmeier, C., Suarez, R. Gonzalez, Monroy, J., Siado, J., Bartz, E., Gershtein, Y., Halkiadakis, E., Kyriacou, S., Lath, A., Schnetzer, S., Stone, R., Walker, M., Malik, S., Norberg, S., Vargas, J. E. Ramirez, Alyari, M., Dolen, J., Godshalk, A., Harrington, C., Iashvili, I., Kharchilava, A., Nguyen, D., Parker, A., Rappoccio, S., Roozbahani, B., Alexander, J., Chaves, J., Chu, J., Dittmer, S., McDermott, K., Mirman, N., Rinkevicius, A., Ryd, A., Salvati, E., Skinnari, L., Soffi, L., Tao, Z., Thom, J., Tucker, J., Zientek, M., Akgün, B., Ecklund, K. M., Kilpatrick, M., Nussbaum, T., Zabel, J., D'Angelo, P., Johns, W., and Rose, K.

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

A new pixel detector for the CMS experiment was built in order to cope with the instantaneous luminosities anticipated for the Phase~I Upgrade of the LHC. The new CMS pixel detector provides four-hit tracking with a reduced material budget as well as new cooling and powering schemes. A new front-end readout chip mitigates buffering and bandwidth limitations, and allows operation at low comparator thresholds. In this paper, comprehensive test beam studies are presented, which have been conducted to verify the design and to quantify the performance of the new detector assemblies in terms of tracking efficiency and spatial resolution. Under optimal conditions, the tracking efficiency is $99.95\pm0.05\,\%$, while the intrinsic spatial resolutions are $4.80\pm0.25\,\mu \mathrm{m}$ and $7.99\pm0.21\,\mu \mathrm{m}$ along the $100\,\mu \mathrm{m}$ and $150\,\mu \mathrm{m}$ pixel pitch, respectively. The findings are compared to a detailed Monte Carlo simulation of the pixel detector and good agreement is found.

Published
2017
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37. Evidence for depletion of heavy silicon isotopes at comet 67P/Churyumov-Gerasimenko

Author

Rubin, M., Altwegg, K., Balsiger, H., Berthelier, J. -J., Bieler, A., Calmonte, U., Combi, M., De Keyser, J., Engrand, C., Fiethe, B., Fuselier, S. A., Gasc, S., Gombosi, T. I., Hansen, K. C., Hässig, M., Roy, L. Le, Mezger, K., Tzou, C. -Y., Wampfler, S. F., and Wurz, P.

Subjects
Astrophysics - Earth and Planetary Astrophysics, Astrophysics - Solar and Stellar Astrophysics
Abstract

Context. The Rosetta Orbiter Spectrometer for Ion and Neutral Analysis (ROSINA) was designed to measure the composition of the gas in the coma of comet 67P/Churyumov-Gerasimenko, the target of the European Space Agency's Rosetta mission. In addition to the volatiles, ROSINA measured refractories sputtered off the comet by the interaction of solar wind protons with the surface of the comet. Aims. The origin of different solar system materials is still heavily debated. Isotopic ratios can be used to distinguish between different reservoirs and investigate processes occurring during the formation of the solar system. Methods. ROSINA consisted of two mass spectrometers and a pressure sensor. In the ROSINA Double Focusing Mass Spectrometer (DFMS), the neutral gas of cometary origin was ionized and then deflected in an electric and a magnetic field that separated the ions based on their mass-to-charge ratio. The DFMS had a high mass resolution, dynamic range, and sensitivity that allowed detection of rare species and the known major volatiles. Results. We measured the relative abundance of all three stable silicon isotopes with the ROSINA instrument on board the Rosetta spacecraft. Furthermore, we measured $^{13}$C/$^{12}$C in C$_2$H$_4$, C$_2$H$_5$, and CO. The DFMS in situ measurements indicate that the average silicon isotopic composition shows depletion in the heavy isotopes $^{29}$Si and $^{30}$Si with respect to $^{28}$Si and solar abundances, while $^{13}$C to $^{12}$C is analytically indistinguishable from bulk planetary and meteorite compositions. Although the origin of the deficiency of the heavy silicon isotopes cannot be explained unambiguously, we discuss mechanisms that could have contributed to the measured depletion of the isotopes $^{29}$Si and $^{30}$Si., Comment: Accepted for publication in Astronomy & Astrophysics

Published
2017
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38. Uranus' aurorae past equinox

Author

Lamy, L., Prangé, R., Hansen, K. C., Tao, C., Cowley, S. W. H., Stallard, T., Melin, H., Achilleos, N., Guio, P., Badman, S. V., Kim, T., and Pogorelov, N.

Subjects
Astrophysics - Earth and Planetary Astrophysics
Abstract

The aurorae of Uranus were recently detected in the far ultraviolet with the Hubble Space Telescope (HST) providing a new, so far unique, means to remotely study the asymmetric Uranian magnetosphere from Earth. We analyze here two new HST Uranus campaigns executed in Sept. 2012 and Nov. 2014 with different temporal coverage and under variable solar wind conditions numerically predicted by three different MHD codes. Overall, HST images taken with the Space Telescope Imaging Spectrograph reveal auroral emissions in three pairs of successive images (one pair acquired in 2012 and two in 2014), hence six additional auroral detections in total, including the most intense Uranian aurorae ever seen with HST. The detected emissions occur close the expected arrival of interplanetary shocks. They appear as extended spots at southern latitudes, rotating with the planet. They radiate 5-24 kR and 1.3-8.8 GW of ultraviolet emission from H$_2$, last for tens of minutes and vary on timescales down to a few seconds. Fitting the 2014 observations with model auroral ovals constrains the longitude of the southern (northern) magnetic pole to 104+\-26{\deg} (284-\-26{\deg}) in the Uranian Longitude System. We suggest that the Uranian near-equinoctial aurorae are pulsed cusp emissions possibly triggered by large-scale magnetospheric compressions., Comment: 10 pages, 5 Figures

Published
2017
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39. Longitudinal analysis of the skin microbiome in association with hand eczema, hand hygiene practices and moisturizer use.

Author

Vindenes, H. K., Drengenes, C., Amin, H., Irgens‐Hansen, K., Svanes, C., and Bertelsen, R. J.

Subjects
HAND washing, HAND care & hygiene, MICROBIAL diversity, BACTERIAL communities, CORYNEBACTERIUM
Abstract

Background: The skin microbiota maintains a physical and immunological barrier to the environment. Little is known about how the microbiome changes over time or the effect of hand hygiene practices and moisturizer use. Objectives: To assess sex‐specific changes in skin bacteria over time, and how the microbiome is related to self‐reported hand eczema, hand hygiene practices and use of moisturizers. Methods: Swab samples from the dorsal hand were collected at baseline and 6.5 years later during the COVID‐19 pandemic, in 168 participants from the RHINESSA study in Bergen, Norway. The skin samples were analysed by 16S rRNA amplicon sequencing. Results: The alpha diversity of the hand microbiome increased from baseline to follow‐up, and beta diversity differed by sex at both time points. The relative abundance increased for several bacteria from baseline to follow‐up, with sex‐specific differences. Current hand eczema and aggravating hand eczema during the COVID‐19 pandemic were associated with an increase in Staphylococcus. High hand washing frequency at home was associated with lower alpha diversity and with higher abundance of Staphylococcus, Corynebacterium, Finegoldia, and Pseudomonas and lower abundance of Propionibacterium and Pelomonas. The alpha diversity increased with increasing time passing between hand washing and sampling, whereas more frequent moisturizer use was associated with significantly lower alpha diversity, and a change in abundance for some bacteria, such as more Pseudomonas. Conclusions: This longitudinal study revealed an overall increase in skin microbial diversity over a 6‐year period, which was unexpected since follow‐up was performed during the COVID‐19 pandemic when vigorous hand hygienic practices were introduced. Sex‐specific differences were identified at both time points. Individuals with hand eczema seem to develop a more dysbiotic skin bacterial community over time. Hand washing and use of moisturizers, with typically gender‐specific habitual patterns, may lead to change in bacterial composition. [ABSTRACT FROM AUTHOR]

Published
2024
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47. Association of serum and fecal microRNA profiles in healthy cats and cats with gastrointestinal cancer or chronic inflammatory enteropathy

Author

Lyngby, JG, Brogaard, L, Kristensen, AT, Fredholm, MF, Bjørnvad, C, Salavati Schmitz, S, Skancke, E, Morris, J, Dupont, N, Argyle, D, Sánchez, S, Spohr, A, Graarup-Hansen, K, Nielsen, L, Cirera, S, Lyngby, JG, Brogaard, L, Kristensen, AT, Fredholm, MF, Bjørnvad, C, Salavati Schmitz, S, Skancke, E, Morris, J, Dupont, N, Argyle, D, Sánchez, S, Spohr, A, Graarup-Hansen, K, Nielsen, L, and Cirera, S

Published
2024

48. Trapping in irradiated p-on-n silicon sensors at fluences anticipated at the HL-LHC outer tracker

Author

Adam, W., Bergauer, T., Dragicevic, M., Friedl, M., Fruehwirth, R., Hoch, M., Hrubec, J., Krammer, M., Treberspurg, W., Waltenberger, W., Alderweireldt, S., Beaumont, W., Janssen, X., Luyckx, S., Van Mechelen, P., Van Remortel, N., Van Spilbeeck, A., Barria, P., Caillol, C., Clerbaux, B., De Lentdecker, G., Dobur, D., Favart, L., Grebenyuk, A., Lenzi, Th., Léonard, A., Maerschalk, Th., Mohammadi, A., Perniè, L., Randle-Conde, A., Reis, T., Seva, T., Thomas, L., Velde, C. Vander, Vanlaer, P., Wang, J., Zenoni, F., Zeid, S. Abu, Blekman, F., De Bruyn, I., D'Hondt, J., Daci, N., Deroover, K., Heracleous, N., Keaveney, J., Lowette, S., Moreels, L., Olbrechts, A., Python, Q., Tavernier, S., Van Mulders, P., Van Onsem, G., Van Parijs, I., Strom, D. A., Caudron, A., Ceard, L., De Callatay, B., Delaere, C., Pree, T. Du, Forthomme, L., Giammanco, A., Hollar, J., Jez, P., Michotte, D., Nuttens, C., Perrini, L., Pagano, D., Quertenmont, L., Selvaggi, M., Marono, M. Vidal, Beliy, N., Caebergs, T., Daubie, E., Hammad, G. H., Härkönen, J., Lampén, T., Luukka, P. -R., Mäenpää, T., Peltola, T., Tuominen, E., Tuovinen, E., Eerola, P., Tuuva, T., Beaulieu, G., Boudoul, G., Combaret, C., Contardo, D., Gallbit, G., Lumb, N., Mathez, H., Mirabito, L., Perries, S., Sabes, D., Donckt, M. Vander, Verdier, P., Viret, S., Zoccarato, Y., Agram, J. -L., Conte, E., Fontaine, J. -Ch., Andrea, J., Bloch, D., Bonnin, C., Brom, J. -M., Chabert, E., Charles, L., Goetzmann, Ch., Gross, L., Hosselet, J., Mathieu, C., Richer, M., Skovpen, K., Autermann, C., Edelhoff, M., Esser, H., Feld, L., Karpinski, W., Klein, K., Lipinski, M., Ostapchuk, A., Pierschel, G., Preuten, M., Raupach, F., Sammet, J., Schael, S., Schwering, G., Wittmer, B., Wlochal, M., Zhukov, V., Pistone, C., Fluegge, G., Kuensken, A., Geisler, M., Pooth, O., Stahl, A., Bartosik, N., Behr, J., Burgmeier, A., Calligaris, L., Dolinska, G., Eckerlin, G., Eckstein, D., Eichhorn, T., Fluke, G., Garcia, J. Garay, Gizhko, A., Hansen, K., Harb, A., Hauk, J., Kalogeropoulos, A., Kleinwort, C., Korol, I., Lange, W., Lohmann, W., Mankel, R., Maser, H., Mittag, G., Muhl, C., Mussgiller, A., Nayak, A., Ntomari, E., Perrey, H., Pitzl, D., Schroeder, M., Seitz, C., Spannagel, S., Zuber, A., Biskop, H., Blobel, V., Buhmann, P., Centis-Vignali, M., Draeger, A. -R., Erfle, J., Garutti, E., Haller, J., Hoffmann, M., Junkes, A., Lapsien, T., Mättig, S., Matysek, M., Perieanu, A., Poehlsen, J., Poehlsen, T., Scharf, Ch., Schleper, P., Schmidt, A., Sola, V., Steinbrück, G., Wellhausen, J., Barvich, T., Barth, Ch., Boegelspacher, F., De Boer, W., Butz, E., Casele, M., Colombo, F., Dierlamm, A., Eber, R., Freund, B., Hartmann, F., Hauth, Th., Heindl, S., Hoffmann, K. -H., Husemann, U., Kornmeyer, A., Mallows, S., Muller, Th., Nuernberg, A., Printz, M., Simonis, H. J., Steck, P., Weber, M., Weiler, Th., Bhardwaj, A., Kumar, A., Ranjan, K., Bakhshiansohl, H., Behnamian, H., Khakzad, M., Naseri, M., Cariola, P., De Robertis, G., Fiore, L., Franco, M., Loddo, F., Sala, G., Silvestris, L., Creanza, D., De Palma, M., Maggi, G., My, S., Selvaggi, G., Albergo, S., Cappello, G., Chiorboli, M., Costa, S., Giordano, F., Di Mattia, A., Potenza, R., Saizu, M. A., Tricomi, A., Tuvè, C., Barbagli, G., Brianzi, M., Ciaranfi, R., Civinini, C., Gallo, E., Meschini, M., Paoletti, S., Sguazzoni, G., Ciulli, V., D'Alessandro, R., Gonzi, S., Gori, V., Focardi, E., Lenzi, P., Scarlini, E., Tropiano, A., Viliani, L., Ferro, F., Robutti, E., Vetere, M. Lo, Gennai, S., Malvezzi, S., Menasce, D., Moroni, L., Pedrini, D., Dinardo, M., Fiorendi, S., Manzoni, R. A., Azzi, P., Bacchetta, N., Bisello, D., Dall'Osso, M., Dorigo, T., Giubilato, P., Pozzobon, N., Tosi, M., Zucchetta, A., De Canio, F., Gaioni, L., Manghisoni, M., Nodari, B., Re, V., Traversi, G., Comotti, D., Ratti, L., Bilei, G. M., Bissi, L., Checcucci, B., Magalotti, D., Menichelli, M., Saha, A., Servoli, L., Storchi, L., Biasini, M., Conti, E., Ciangottini, D., Fanò, L., Lariccia, P., Mantovani, G., Passeri, D., Placidi, P., Salvatore, M., Santocchia, A., Solestizi, L. A., Spiezia, A., Androsov, K., Azzurri, P., Arezzini, S., Bagliesi, G., Basti, A., Boccali, T., Bosi, F., Castaldi, R., Ciampa, A., Cioccid, M. A., Dell'Orso, R., Fedi, G., Giassi, A., Grippod, M. T., Lomtadze, T., Magazzu, G., Mazzoni, E., Minuti, M., Moggi, A., Moond, C. S., Morsani, F., Palla, F., Palmonari, F., Raffaelli, F., Savoy-Navarro, A., Serban, A. T., Spagnolo, P., Tenchini, R., Venturi, A., Verdini, P. G., Martini, L., Messineo, A., Rizzi, A., Tonelli, G., Calzolari, F., Donato, S., Fiori, F., Ligabue, F., Vernieri, C., Demaria, N., Rivetti, A., Bellan, R., Casasso, S., Costa, M., Covarelli, R., Migliore, E., Monteil, E., Musich, M., Pacher, L., Ravera, F., Romero, A., Solano, A., Trapani, P., Echeverria, R. Jaramillo, Fernandez, M., Gomez, G., Moya, D., Sanchez, F. J. Gonzalez, Sanchez, F. J. Munoz, Vila, I., Virto, A. L., Abbaneo, D., Ahmed, I., Albert, E., Auzinger, G., Berruti, G., Bianchi, G., Blanchot, G., Breuker, H., Ceresa, D., Christiansen, J., Cichy, K., Daguin, J., D'Alfonso, M., D'Auria, A., Detraz, S., De Visscher, S., Deyrail, D., Faccio, F., Felici, D., Frank, N., Gill, K., Giordano, D., Harris, P., Honma, A., Kaplon, J., Kornmayer, A., Kottelat, L., Kovacs, M., Mannelli, M., Marchioro, A., Marconi, S., Martina, S., Mersi, S., Michelis, S., Moll, M., Onnela, A., Pakulski, T., Pavis, S., Peisert, A., Pernot, J. -F., Petagna, P., Petrucciani, G., Postema, H., Rose, P., Rzonca, M., Stoye, M., Tropea, P., Troska, J., Tsirou, A., Vasey, F., Vichoudis, P., Verlaat, B., Zwalinski, L., Bachmair, F., Becker, R., Bäni, L., di Calafiori, D., Casal, B., Djambazov, L., Donega, M., Dünser, M., Eller, P., Grab, C., Hits, D., Horisberger, U., Hoss, J., Kasieczka, G., Lustermann, W., Mangano, B., Marionneau, M., del Arbol, P. Martinez Ruiz, Masciovecchio, M., Perrozzi, L., Roeser, U., Rossini, M., Starodumov, A., Takahashi, M., Wallny, R., Amsler, C., Bösiger, K., Caminada, L., Canelli, F., Chiochia, V., de Cosa, A., Galloni, C., Hreus, T., Kilminster, B., Lange, C., Maier, R., Ngadiuba, J., Pinna, D., Robmann, P., Taroni, S., Yang, Y., Bertl, W., Deiters, K., Erdmann, W., Horisberger, R., Kaestli, H. -C., Kotlinski, D., Langenegger, U., Meier, B., Rohe, T., Streuli, S., Chen, P. -H., Dietz, C., Grundler, U., Hou, W. -S., Lu, R. -S., Moya, M., Wilken, R., Cussans, D., Flacher, H., Goldstein, J., Grimes, M., Jacob, J., Nasr-Storey, S. Seif El, Cole, J., Hobson, P., Leggat, D., Reid, I. D., Teodorescu, L., Bainbridge, R., Dauncey, P., Fulcher, J., Hall, G., Magnan, A. -M., Pesaresi, M., Raymond, D. M., Uchida, K., Coughlan, J. A., Harder, K., Ilic, J., Tomalin, I. R., Garabedian, A., Heintz, U., Narain, M., Nelson, J., Sagir, S., Speer, T., Swanson, J., Tersegno, D., Watson-Daniels, J., Chertok, M., Conway, J., Conway, R., Flores, C., Lander, R., Pellett, D., Ricci-Tam, F., Squires, M., Thomson, J., Yohay, R., Burt, K., Ellison, J., Hanson, G., Malberti, M., Olmedo, M., Cerati, G., Sharma, V., Vartak, A., Yagil, A., Della Porta, G. Zevi, Dutta, V., Gouskos, L., Incandela, J., Kyre, S., McColl, N., Mullin, S., White, D., Cumalat, J. P., Ford, W. T., Gaz, A., Krohn, M., Stenson, K., Wagner, S. R., Baldin, B., Bolla, G., Burkett, K., Butler, J., Cheung, H., Chramowicz, J., Christian, D., Cooper, W. E., Deptuch, G., Derylo, G., Gingu, C., Gruenendahl, S., Hasegawa, S., Hoff, J., Howell, J., Hrycyk, M., Jindariani, S., Johnson, M., Jung, A., Joshi, U., Kahlid, F., Lei, C. M., Lipton, R., Liu, T., Los, S., Matulik, M., Merkel, P., Nahn, S., Prosser, A., Rivera, R., Shenai, A., Spiegel, L., Tran, N., Uplegger, L., Voirin, E., Yin, H., Adams, M. R., Berry, D. R., Evdokimov, A., Evdokimov, O., Gerber, C. E., Hofman, D. J., Kapustka, B. K., O'Brien, C., Gonzalez, D. I. Sandoval, Trauger, H., Turner, P., Parashar, N., Stupak, J., Bortoletto, D., Bubna, M., Hinton, N., Jones, M., Miller, D. H., Shi, X., Tan, P., Baringer, P., Bean, A., Benelli, G., Gray, J., Majumder, D., Noonan, D., Sanders, S., Stringer, R., Ivanov, A., Makouski, M., Skhirtladze, N., Taylor, R., Anderson, I., Fehling, D., Gritsan, A., Maksimovic, P., Martin, C., Nash, K., Osherson, M., Swartz, M., Xiao, M., Acosta, J. G., Cremaldi, L. M., Oliveros, S., Perera, L., Summers, D., Bloom, K., Bose, S., Claes, D. R., Dominguez, A., Fangmeier, C., Suarez, R. Gonzalez, Meier, F., Monroy, J., Hahn, K., Sevova, S., Sung, K., Trovato, M., Bartz, E., Duggan, D., Halkiadakis, E., Lath, A., Park, M., Schnetzer, S., Stone, R., Walker, M., Malik, S., Mendez, H., Vargas, J. E. Ramirez, Alyari, M., Dolen, J., George, J., Godshalk, A., Iashvili, I., Kaisen, J., Kharchilava, A., Rappoccio, S., Alexander, J., Chaves, J., Chu, J., Dittmer, S., Kaufman, G., Mirman, N., Ryd, A., Salvati, E., Skinnari, L., Thom, J., Thompson, J., Tucker, J., Winstrom, L., Akgün, B., Ecklund, K. M., Nussbaum, T., Zabel, J., Betchart, B., Demina, R., Hindrichs, O., Petrillo, G., Eusebi, R., Osipenkov, I., Perloff, A., Ulmer, K. A., Delannoy, A. G., D'Angelo, P., and Johns, W.

Subjects
Physics - Instrumentation and Detectors
Abstract

The degradation of signal in silicon sensors is studied under conditions expected at the CERN High-Luminosity LHC. 200 $\mu$m thick n-type silicon sensors are irradiated with protons of different energies to fluences of up to $3 \cdot 10^{15}$ neq/cm$^2$. Pulsed red laser light with a wavelength of 672 nm is used to generate electron-hole pairs in the sensors. The induced signals are used to determine the charge collection efficiencies separately for electrons and holes drifting through the sensor. The effective trapping rates are extracted by comparing the results to simulation. The electric field is simulated using Synopsys device simulation assuming two effective defects. The generation and drift of charge carriers are simulated in an independent simulation based on PixelAV. The effective trapping rates are determined from the measured charge collection efficiencies and the simulated and measured time-resolved current pulses are compared. The effective trapping rates determined for both electrons and holes are about 50% smaller than those obtained using standard extrapolations of studies at low fluences and suggests an improved tracker performance over initial expectations.

Published
2015
Full Text
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49. A Helium Gas-Scintillator Active Target for Photoreaction Measurements

Author

Jebali, R. Al, Annand, J. R. M., Adler, J. -O., Akkurt, I., Buchanan, E., Brudvik, J., Fissum, K., Gardner, S., Hamilton, D. J., Hansen, K., Isaksson, L., Livingston, K., Lundin, M., McGeorge, J. C., MacGregor, I. J. D., MacRae, R., Middleton, D. G., Reiter, A. J. H., Rosner, G., Schröder, B., Sjögren, J., Sokhan, D., and Strandberg, B.

Subjects
Physics - Instrumentation and Detectors, Nuclear Experiment
Abstract

A multi-cell He gas-scintillator active target, designed for the measurement of photoreaction cross sections, is described. The target has four main chambers, giving an overall thickness of 0.103 $\mathrm{g/cm^{2}}$ at an operating pressure of 2 MPa. Scintillations are read out by photomultiplier tubes and the addition of small amounts of $\mathrm{N}_{2}$ to the He, to shift the scintillation emission from UV to visible, is discussed. First results of measurements at the MAX IV Laboratory tagged-photon facility show that the target has good timing resolution and can cope well with a high-flux photon beam. The determination of reaction cross sections from target yields relies on a Monte Carlo simulation, which considers scintillation light transport, photodisintegration processes in $^{4}\mathrm{He}$, background photon interactions in target windows and interactions of the reaction-product particles in the gas and target container. The predictions of this simulation are compared to the measured target response., Comment: 24 pages, 15 figures

Published
2015

50. Classical crystal formation of dipoles in two dimensions

Author

Hansen, K. K., Fedorov, D. V., Jensen, A. S., and Zinner, N. T.

Subjects
Condensed Matter - Quantum Gases, Condensed Matter - Other Condensed Matter, Physics - Classical Physics
Abstract

We consider a two-dimensional layer of dipolar particles in the regime of strong dipole moments. Here we can describe the system using classical methods and determine the crystal structure that minimizes the total energy. The dipoles are assumed to be aligned by an external field and we consider different orientations of the dipolar moments with respect to the two-dimensional plane of motion. We observe that when the orientation angle changes away from perpendicular and towards the plane, the crystal structure will change from a hexagonal form to one that has the dipoles sitting in equidistant rows, i.e. a striped configuration. In addition to calculating the crystal unit cell, we also consider the phonon spectrum and the speed of sound. As the orientation changes away from perpendicular the phonon spectrum develops local minima that are a result of the deformation to the crystal structure., Comment: 12 pages, 12 figures, 1 appendix, published version

Published
2015
Full Text
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