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1. Macroscopic analysis and modelling of multi-class, flexible-lane traffic

Author

Knoop, Victor L., Schakel, Wouter J., van Oijen, Tim P., and Leclercq, Ludovic

Subjects
Physics - Physics and Society
Abstract

An excessive demand of vehicles to a motorway bottleneck leads to traffic jams. Motorbikes are narrow and can drive next to each other in a lane, or in-between lanes in low speeds. This paper analyses the resulting traffic characteristics and presents numerical scheme for a macroscopic traffic flow model for these two classes. The behavior included is as follows. If there are two motorbikes behind each other, they can travel next to each other in one lane, occupying the space of one car. Also, at low speeds of car traffic, they can go in between the main lanes, creating a so-called filtering lane. The paper numerically derives functions of class-specific speeds as function of the density of both classes, incorporating flexible lane usage dependent on the speed. The roadway capacity as function of the motorbike fraction is derived, which interesting can be in different types of phases (with motorbikes at higher speeds or not). We also present a numerical scheme to analyse the dynamics of this multi-class system. We apply the model to an example case, revealing the properties of the traffic stream , queue dynamics and class specific travel times. The model can help in showing the relative advantage in travel time of switching to a motorbike.

Published
2023

3. The multiple mediating effects of vision-specific factors and depression on the association between visual impairment severity and fatigue: a path analysis study

Author

Wouter Schakel, Christina Bode, Peter M. van de Ven, Hilde P. A. van der Aa, Carel T. J. Hulshof, Gerardus H. M. B. van Rens, and Ruth M. A. van Nispen

Subjects
Visual impairment, Fatigue, Depression, Vision-specific quality of life, Low vision, Structural equation modeling, Psychiatry, RC435-571
Abstract

Abstract Background Severe fatigue is a common symptom for people with visual impairment, with a detrimental effect on emotional functioning, cognition, work capacity and activities of daily living. A previous study found that depression was one of the most important determinants of fatigue, but less is known about disease-specific factors in this patient population. This study aimed to explore the association between visual impairment severity and fatigue in adults with low vision, both directly and indirectly, with vision-specific factors and depression as potential mediators. Methods Cross-sectional data were collected from 220 Dutch low vision service patients by telephone interviews. Fatigue was defined as a latent variable by severity and impact on daily life. Potential mediators included vision-related symptoms, adaptation to vision loss and depression. Hypothesized structural equation models were constructed in Mplus to test (in)direct effects of visual impairment severity (mild/moderate, severe, blindness) on fatigue through above mentioned variables. Results The final model explained 60% of fatigue variance and revealed a significant total effect of visual impairment severity on fatigue. Patients with severe visual impairment (reference group) had significantly higher fatigue symptoms compared to those with mild/moderate visual impairment (β = -0.50, 95% bias-corrected confidence interval [BC CI] [-0.86, -0.16]) and those with blindness (β = -0.44, 95% BC CI [-0.80, -0.07]). Eye strain & light disturbance, depression and vision-related mobility mediated the fatigue difference between the severe and mild/moderate visual impairment categories. The fatigue difference between the severe visual impairment and blindness categories was solely explained by eye strain & light disturbance. Moreover, depressive symptoms (β = 0.65, p

Published
2024
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4. Towards retrospective motion correction and reconstruction for clinical 3D brain MRI protocols with a reference contrast

Author

Rizzuti, Gabrio, Schakel, Tim, Huttinga, Niek R. F., Dankbaar, Jan Willem, van Leeuwen, Tristan, and Sbrizzi, Alessandro

Subjects
Electrical Engineering and Systems Science - Image and Video Processing
Abstract

Motion artifacts often spoil the radiological interpretation of MR images, and in the most severe cases the scan needs be repeated, with additional costs for the provider. We discuss the application of a novel 3D retrospective rigid motion correction and reconstruction scheme for MRI, which leverages multiple scans contained in a MR session. Typically, in a multi-contrast MR session, motion does not equally affect all the scans, and some motion-free scans are generally available, so that we can exploit their anatomic similarity. The uncorrupted scan is used as a reference in a generalized rigid-motion registration problem to remove the motion artifacts affecting the corrupted scans. We discuss the potential of the proposed algorithm with a prospective in-vivo study and clinical 3D brain protocols. This framework can be easily incorporated into the existing clinical practice with no disruption to the conventional workflow.

Published
2023

5. Technical Design Report for the PANDA Endcap Disc DIRC

Author

Panda Collaboration, Davi, F., Erni, W., Krusche, B., Steinacher, M., Walford, N., Liu, H., Liu, Z., Liu, B., Shen, X., Wang, C., Zhao, J., Albrecht, M., Erlen, T., Feldbauer, F., Fink, M., Freudenreich, V., Fritsch, M., Heinsius, F. H., Held, T., Holtmann, T., Keshk, I., Koch, H., Kopf, B., Kuhlmann, M., Kümmel, M., Leiber, S., Musiol, P., Mustafa, A., Pelizäus, M., Pitka, A., Reicherz, G., Richter, M., Schnier, C., Schröder, T., Sersin, S., Sohl, L., Sowa, C., Steinke, M., Triffterer, T., Wiedner, U., Beck, R., Hammann, C., Hartmann, J., Ketzer, B., Kube, M., Rossbach, M., Schmidt, C., Schmitz, R., Thoma, U., Urban, M., Bianconi, A., Bragadireanu, M., Pantea, D., Czyzycki, W., Domagala, M., Filo, G., Jaworowski, J., Krawczyk, M., Lisowski, E., Lisowski, F., Michalek, M., Plazek, J., Korcyl, K., Kozela, A., Kulessa, P., Lebiedowicz, P., Pysz, K., Schäfer, W., Szczurek, A., Fiutowski, T., Idzik, M., Mindur, B., Swientek, K., Biernat, J., Kamys, B., Kistryn, S., Korcyl, G., Krzemien, W., Magiera, A., Moskal, P., Przygoda, W., Rudy, Z., Salabura, P., Smyrski, J., Strzempek, P., Wronska, A., Augustin, I., Böhm, R., Lehmann, I., Marinescu, D. Nicmorus, Schmitt, L., Varentsov, V., Al-Turany, M., Belias, A., Deppe, H., Veis, N. Divani, Dzhygadlo, R., Flemming, H., Gerhardt, A., Götzen, K., Karabowicz, R., Kurilla, U., Lehmann, D., Löchner, S., Lühning, J., Lynen, U., Nakhoul, S., Orth, H., Peters, K., Saito, T., Schepers, G., Schmidt, C. J., Schwarz, C., Schwiening, J., Täschner, A., Traxler, M., Voss, B., Wieczorek, P., Wilms, A., Abazov, V., Alexeev, G., Arefiev, V. A., Astakhov, V., Barabanov, M. Yu., Batyunya, B. V., Dodokhov, V. Kh., Efremov, A., Fechtchenko, A., Galoyan, A., Golovanov, G., Koshurnikov, E. K., Lobanov, Y. Yu., Lobanov, V. I., Malyshev, V., Olshevskiy, A. G., Piskun, A. A., Samartsev, A., Sapozhnikov, M. G., Skachkov, N. B., Skachkova, A. N., Strokovsky, E. A., Tokmenin, V., Uzhinsky, V., Verkheev, A., Vodopianov, A., Zhuravlev, N. I., Zinchenko, A., Branford, D., Glazier, D., Watts, D., Böhm, M., Eyrich, W., Lehmann, A., Miehling, D., Pfaffinger, M., Stelter, S., Uhlig, F., Dobbs, S., Seth, K., Tomaradze, A., Xiao, T., Bettoni, D., Ali, A., Hamdi, A., Krebs, M., Nerling, F., Akishina, V., Gorbunov, S., Kisel, I., Kozlov, G., Pugach, M., Zyzak, M., Bianchi, N., Gianotti, P., Guaraldo, C., Lucherini, V., Bracco, G., Bodenschatz, S., Brinkmann, K. T., Di Pietro, V., Diehl, S., Dormenev, V., Düren, M., Etzelmüller, E., Föhl, K., Galuska, M., Geßler, T., Gutz, E., Hahn, C., Hayrapetyan, A., Kesselkaul, M., Kühn, W., Kuske, T., Lange, J. S., Liang, Y., Metag, V., Moritz, M., Nanova, M., Novotny, R., Quagli, T., Riccardi, A., Rieke, J., Schmidt, M., Schnell, R., Stenzel, H., Strickert, M., Thöring, U., Wasem, T., Wohlfahrt, B., Zaunick, H. G., Tomasi-Gustafsson, E., Ireland, D., Rosner, G., Seitz, B., Deepak, P. N., Kulkarni, A., Apostolou, A., Babai, M., Kavatsyuk, M., Loehner, H., Messchendorp, J., Schakel, P., Tiemens, M., van der Weele, J. C., Vejdani, S., Dutta, K., Kalita, K., Sohlbach, H., Bai, M., Bianchi, L., Büscher, M., Derichs, A., Dosdall, R., Erven, A., Fracassi, V., Gillitzer, A., Goldenbaum, F., Grunwald, D., Jokhovets, L., Kemmerling, G., Kleines, H., Lai, A., Lehrach, A., Mikirtychyants, M., Orfanitski, S., Prasuhn, D., Prencipe, E., Pütz, J., Ritman, J., Rosenthal, E., Schadmand, S., Sefzick, T., Serdyuk, V., Sterzenbach, G., Stockmanns, T., Wintz, P., Wüstner, P., Xu, H., Zhou, Y., Li, Z., Ma, X., Rigato, V., Isaksson, L., Achenbach, P., Aycock, A., Corell, O., Denig, A., Distler, M., Hoek, M., Lauth, W., Merkel, H., Müller, U., Pochodzalla, J., Sanchez, S., Schlimme, S., Sfienti, C., Thiel, M., Zambrana, M., Ahmadi, H., Ahmed, S., Bleser, S., Capozza, L., Cardinali, M., Dbeyssi, A., Ehret, A., Fröhlich, B., Grasemann, P., Haasler, S., Izard, D., Jorge, J., Khaneft, D., Klasen, R., Kliemt, R., Köhler, J., Leithoff, H. H., Lin, D., Maas, F., Maldaner, S., Michel, M., Espi, M. C. Mora, Morales, C. Morales, Motzko, C., Noll, O., Pflüger, S., Pineiro, D. Rodriguez, Steinen, M., Walaa, E., Wolff, S., Zimmermann, I., Fedorov, A., Korzhik, M., Missevitch, O., Balanutsa, P., Chernetsky, V., Demekhin, A., Dolgolenko, A., Fedorets, P., Gerasimov, A., Goryachev, V., Kirin, D. Y., Matveev, V. A., Stavinskiy, A. V., Balashoff, A., Boukharov, A., Malyshev, O., Marishev, I., Chandratre, V., Datar, V., Jha, V., Kumawat, H., Mohanty, A. K., Parmar, A., Rai, A. K., Roy, B., Sonika, G., Fritzsch, C., Grieser, S., Hergemöller, A. K., Hetz, B., Hüsken, N., Khoukaz, A., Wessels, J. P., Herold, C., Khosonthongkee, K., Kobdaj, C., Limphirat, A., Srisawad, P., Yan, Y., Blinov, A. E., Kononov, S., Kravchenko, E. A., Antokhin, E., Barnyakov, M., Barnyakov, A. Yu., Beloborodov, K., Blinov, V. E., Bobrovnikov, V. S., Kuyanov, I. A., Onuchin, A. P., Pivovarov, S., Pyata, E., Serednyakov, S., Tikhonov, Y., Kunne, R., Marchand, D., Ramstein, B., van de Wiele, J., Wang, Y., Boca, G., Burian, V., Finger, M., Nikolovova, A., Pesek, M., Peskova, M., Pfeffer, M., Prochazka, I., Slunecka, M., Gallus, P., Jary, V., Novy, J., Tomasek, M., Virius, M., Vrba, V., Abramov, V., Belikov, N., Bukreeva, S., Davidenko, A., Derevschikov, A., Goncharenko, Y., Grishin, V., Kachanov, V., Kormilitsin, V., Levin, A., Melnik, Y., Minaev, N., Mochalov, V., Morozov, D., Nogach, L., Poslavskiy, S., Ryazantsev, A., Ryzhikov, S., Semenov, P., Shein, I., Uzunian, A., Vasiliev, A., Yakutin, A., Roy, U., Yabsley, B., Belostotski, S., Gavrilov, G., Izotov, A., Manaenkov, S., Miklukho, O., Veretennikov, D., Zhdanov, A., Bäck, T., Cederwall, B., Makonyi, K., Preston, M., Tegner, P. E., Wölbing, D., Godre, S., Bussa, M. P., Marcello, S., Spataro, S., Iazzi, F., Introzzi, R., Lavagno, A., Calvo, D., De Remigis, P., Filippi, A., Mazza, G., Rivetti, A., Wheadon, R., Martin, A., Calen, H., Andersson, W. Ikegami, Johansson, T., Kupsc, A., Marciniewski, P., Papenbrock, M., Pettersson, J., Regina, J., Schönning, K., Wolke, M., Diaz, J., Chackara, V. Pothodi, Chlopik, A., Kesik, G., Melnychuk, D., Slowinski, B., Trzcinski, A., Wojciechowski, M., Wronka, S., Zwieglinski, B., Bühler, P., Marton, J., Steinschaden, D., Suzuki, K., Widmann, E., Zimmermann, S., and Zmeskal, J.

Subjects
Physics - Instrumentation and Detectors
Abstract

PANDA (anti-Proton ANnihiliation at DArmstadt) is planned to be one of the four main experiments at the future international accelerator complex FAIR (Facility for Antiproton and Ion Research) in Darmstadt, Germany. It is going to address fundamental questions of hadron physics and quantum chromodynamics using cooled antiproton beams with a high intensity and and momenta between 1.5 and 15 GeV/c. PANDA is designed to reach a maximum luminosity of 2x10^32 cm^2 s. Most of the physics programs require an excellent particle identification (PID). The PID of hadronic states at the forward endcap of the target spectrometer will be done by a fast and compact Cherenkov detector that uses the detection of internally reflected Cherenkov light (DIRC) principle. It is designed to cover the polar angle range from 5{\deg} to 22{\deg} and to provide a separation power for the separation of charged pions and kaons up to 3 standard deviations (s.d.) for particle momenta up to 4 GeV/c in order to cover the important particle phase space. This document describes the technical design and the expected performance of the novel PANDA Disc DIRC detector that has not been used in any other high energy physics experiment (HEP) before. The performance has been studied with Monte-Carlo simulations and various beam tests at DESY and CERN. The final design meets all PANDA requirements and guarantees suffcient safety margins., Comment: TDR for Panda/Fair to be published

Published
2019

7. Feasibility of cardiac-synchronized quantitative T1 and T2 mapping on a hybrid 1.5 Tesla magnetic resonance imaging and linear accelerator system

Author

Osman Akdag, Stefano Mandija, Astrid L.H.M.W. van Lier, Pim T.S. Borman, Tim Schakel, Eveline Alberts, Oscar van der Heide, Rutger J. Hassink, Joost J.C. Verhoeff, Firdaus A.A. Mohamed Hoesein, Bas W. Raaymakers, and Martin F. Fast

Subjects
MR-linac, MRI, Quantitative cardiac MRI, MRI-guided radiotherapy, Cardiac MR-linac, Medical physics. Medical radiology. Nuclear medicine, R895-920, Neoplasms. Tumors. Oncology. Including cancer and carcinogens, RC254-282
Abstract

Background and Purpose: The heart is important in radiotherapy either as target or organ at risk. Quantitative T1 and T2 cardiac magnetic resonance imaging (qMRI) may aid in target definition for cardiac radioablation, and imaging biomarker for cardiotoxicity assessment. Hybrid MR-linac devices could facilitate daily cardiac qMRI of the heart in radiotherapy. The aim of this work was therefore to enable cardiac-synchronized T1 and T2 mapping on a 1.5 T MR-linac and test the reproducibility of these sequences on phantoms and in vivo between the MR-linac and a diagnostic 1.5 T MRI scanner. Materials and methods: Cardiac-synchronized MRI was performed on the MR-linac using a wireless peripheral pulse-oximeter unit. Diagnostically used T1 and T2 mapping sequences were acquired twice on the MR-linac and on a 1.5 T MR-simulator for a gel phantom and 5 healthy volunteers in breath-hold. Phantom T1 and T2 values were compared to gold-standard measurements and percentage errors (PE) were computed, where negative/positive PE indicate underestimations/overestimations. Manually selected regions-of-interest were used for in vivo intra/inter scanner evaluation. Results: Cardiac-synchronized T1 and T2 qMRI was enabled after successful hardware installation on the MR-linac. From the phantom experiments, the measured T1/T2 relaxation times had a maximum percentage error (PE) of −4.4%/−8.8% on the MR-simulator and a maximum PE of −3.2%/+8.6% on the MR-linac. Mean T1/T2 of the myocardium were 1012±34/51±2 ms on the MR-simulator and 1034±42/51±1 ms on the MR-linac. Conclusions: Accurate cardiac-synchronized T1 and T2 mapping is feasible on a 1.5 T MR-linac and might enable novel plan adaptation workflows and cardiotoxicity assessments.

Published
2022
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8. Using Cooperative Adaptive Cruise Control (CACC) to Form High-Performance Vehicle Streams. FINAL REPORT

Author

Liu, Hao, Xiao, Lin, Kan, Xingan (David), Shladover, Steven E., Lu, Xiao-Yun, Wang, Meng, Schakel, Wouter, and van Arem, Bart

Abstract

Freeway capacity and throughput can be significantly improved via CACC vehicle string operations. This research aims to provide authoritative predictions regarding impacts of CACC on traffic flow and quantitative estimations of the influences of CACC operation strategies that might create the capacity and throughput improvement in the freeway traffic stream. To this end, the PATH and Delft team have independently developed micro simulation platforms that represent the behaviors of CACC vehicles and their interactions with human drivers. The models have been calibrated using archived data from a complicated 13-mile long section of the northbound SR-99 freeway near Sacramento, California for an 8-hour period in which the traffic fluctuated between free-flow and congested conditions. Calibration results show extremely good agreement between field data and model predictions. The models have been cross-validated and produced similar macroscopic traffic performance. With the simulation platforms, we have explored the effects of CACC under various market penetrations and the impacts of a CACC managed lane (ML) strategy, a vehicle awareness device (VAD) strategy and discretionary lane change (DLC) restrictions on the traffic flow dynamics of a simple four-lane freeway section and the 13-mile freeway corridor.

Published
2018

10. Feasibility study for the measurement of $\pi N$ TDAs at PANDA in $\bar{p}p\to J/\psi\pi^0$

Author

PANDA Collaboration, Singh, B., Erni, W., Krusche, B., Steinacher, M., Walford, N., Liu, H., Liu, Z., Liu, B., Shen, X., Wang, C., Zhao, J., Albrecht, M., Erlen, T., Fink, M., Heinsius, F. H., Held, T., Holtmann, T., Jasper, S., Keshk, I., Koch, H., Kopf, B., Kuhlmann, M., Kümmel, M., Leiber, S., Mikirtychyants, M., Musiol, P., Mustafa, A., Pelizäus, M., Pychy, J., Richter, M., Schnier, C., Schröder, T., Sowa, C., Steinke, M., Triffterer, T., Wiedner, U., Ball, M., Beck, R., Hammann, C., Ketzer, B., Kube, M., Mahlberg, P., Rossbach, M., Schmidt, C., Schmitz, R., Thoma, U., Urban, M., Walther, D., Wendel, C., Wilson, A., Bianconi, A., Bragadireanu, M., Caprini, M., Pantea, D., Patel, B., Czyzycki, W., Domagala, M., Filo, G., Jaworowski, J., Krawczyk, M., Lisowski, E., Lisowski, F., Michałek, M., Poznański, P., Płażek, J., Korcyl, K., Kozela, A., Kulessa, P., Lebiedowicz, P., Pysz, K., Schäfer, W., Szczurek, A., Fiutowski, T., Idzik, M., Mindur, B., Przyborowski, D., Swientek, K., Biernat, J., Kamys, B., Kistryn, S., Korcyl, G., Krzemien, W., Magiera, A., Moskal, P., Pyszniak, A., Rudy, Z., Salabura, P., Smyrski, J., Strzempek, P., Wronska, A., Augustin, I., Böhm, R., Lehmann, I., Marinescu, D. Nicmorus, Schmitt, L., Varentsov, V., Al-Turany, M., Belias, A., Deppe, H., Veis, N. Divani, Dzhygadlo, R., Ehret, A., Flemming, H., Gerhardt, A., Götzen, K., Gromliuk, A., Gruber, L., Karabowicz, R., Kliemt, R., Krebs, M., Kurilla, U., Lehmann, D., Löchner, S., Lühning, J., Lynen, U., Orth, H., Patsyuk, M., Peters, K., Saito, T., Schepers, G., Schmidt, C. J., Schwarz, C., Schwiening, J., Täschner, A., Traxler, M., Ugur, C., Voss, B., Wieczorek, P., Wilms, A., Zühlsdorf, M., Abazov, V., Alexeev, G., Arefiev, V. A., Astakhov, V., Barabanov, M. Yu., Batyunya, B. V., Davydov, Y., Dodokhov, V. Kh., Efremov, A., Fechtchenko, A., Fedunov, A. G., Galoyan, A., Grigoryan, S., Koshurnikov, E. K., Lobanov, Y. Yu., Lobanov, V. I., Makarov, A. F., Malinina, L. V., Malyshev, V., Olshevskiy, A. G., Perevalova, E., Piskun, A. A., Pocheptsov, T., Pontecorvo, G., Rodionov, V., Rogov, Y., Salmin, R., Samartsev, A., Sapozhnikov, M. G., Shabratova, G., Skachkov, N. B., Skachkova, A. N., Strokovsky, E. A., Suleimanov, M., Teshev, R., Tokmenin, V., Uzhinsky, V., Vodopianov, A., Zaporozhets, S. A., Zhuravlev, N. I., Zinchenko, A., Zorin, A. G., Branford, D., Glazier, D., Watts, D., Böhm, M., Britting, A., Eyrich, W., Lehmann, A., Pfaffinger, M., Uhlig, F., Dobbs, S., Seth, K., Tomaradze, A., Xiao, T., Bettoni, D., Carassiti, V., Ramusino, A. Cotta, Dalpiaz, P., Drago, A., Fioravanti, E., Garzia, I., Savrie, M., Akishina, V., Kisel, I., Kozlov, G., Pugach, M., Zyzak, M., Gianotti, P., Guaraldo, C., Lucherini, V., Bersani, A., Bracco, G., Macri, M., Parodi, R. F., Biguenko, K., Brinkmann, K. T., Di Pietro, V., Diehl, S., Dormenev, V., Drexler, P., Düren, M., Etzelmüller, E., Galuska, M., Gutz, E., Hahn, C., Hayrapetyan, A., Kesselkaul, M., Kühn, W., Kuske, T., Lange, J. S., Liang, Y., Metag, V., Moritz, M., Nanova, M., Nazarenko, S., Novotny, R., Quagli, T., Reiter, S., Riccardi, A., Rieke, J., Rosenbaum, C., Schmidt, M., Schnell, R., Stenzel, H., Thöring, U., Ullrich, T., Wagner, M. N., Wasem, T., Wohlfahrt, B., Zaunick, H. G., Tomasi-Gustafsson, E., Ireland, D., Rosner, G., Seitz, B., Deepak, P. N., Kulkarni, A., Apostolou, A., Babai, M., Kavatsyuk, M., Lemmens, P. J., Lindemulder, M., Loehner, H., Messchendorp, J., Schakel, P., Smit, H., Tiemens, M., van der Weele, J. C., Veenstra, R., Vejdani, S., Dutta, K., Kalita, K., Kumar, A., Roy, A., Sohlbach, H., Bai, M., Bianchi, L., Büscher, M., Cao, L., Cebulla, A., Dosdall, R., Gillitzer, A., Goldenbaum, F., Grunwald, D., Herten, A., Hu, Q., Kemmerling, G., Kleines, H., Lai, A., Lehrach, A., Nellen, R., Ohm, H., Orfanitski, S., Prasuhn, D., Prencipe, E., Pütz, J., Ritman, J., Schadmand, S., Sefzick, T., Serdyuk, V., Sterzenbach, G., Stockmanns, T., Wintz, P., Wüstner, P., Xu, H., Zambanini, A., Li, S., Li, Z., Sun, Z., Rigato, V., Isaksson, L., Achenbach, P., Corell, O., Denig, A., Distler, M., Hoek, M., Karavdina, A., Lauth, W., Merkel, H., Müller, U., Pochodzalla, J., Sanchez, S., Schlimme, S., Sfienti, C., Thiel, M., Ahmadi, H., Ahmed, S., Bleser, S., Capozza, L., Cardinali, M., Dbeyssi, A., Deiseroth, M., Feldbauer, F., Fritsch, M., Fröhlich, B., Kang, D., Khaneft, D., Klasen, R., Leithoff, H. H., Lin, D., Maas, F., Maldaner, S., Martínez, M., Michel, M., Espí, M. C. Mora, Morales, C. Morales, Motzko, C., Nerling, F., Noll, O., Pflüger, S., Pitka, A., Piñeiro, D. Rodríguez, Sanchez-Lorente, A., Steinen, M., Valente, R., Weber, T., Zambrana, M., Zimmermann, I., Fedorov, A., Korjik, M., Missevitch, O., Boukharov, A., Malyshev, O., Marishev, I., Balanutsa, V., Balanutsa, P., Chernetsky, V., Demekhin, A., Dolgolenko, A., Fedorets, P., Gerasimov, A., Goryachev, V., Chandratre, V., Datar, V., Dutta, D., Jha, V., Kumawat, H., Mohanty, A. K., Parmar, A., Roy, B., Sonika, G., Fritzsch, C., Grieser, S., Hergemöller, A. K., Hetz, B., Hüsken, N., Khoukaz, A., Wessels, J. P., Khosonthongkee, K., Kobdaj, C., Limphirat, A., Srisawad, P., Yan, Y., Barnyakov, A. Yu., Barnyakov, M., Beloborodov, K., Blinov, V. E., Bobrovnikov, V. S., Kuyanov, I. A., Martin, K., Onuchin, A. P., Serednyakov, S., Sokolov, A., Tikhonov, Y., Blinov, A. E., Kononov, S., Kravchenko, E. A., Atomssa, E., Kunne, R., Ma, B., Marchand, D., Ramstein, B., van de Wiele, J., Wang, Y., Boca, G., Costanza, S., Genova, P., Montagna, P., Rotondi, A., Abramov, V., Belikov, N., Bukreeva, S., Davidenko, A., Derevschikov, A., Goncharenko, Y., Grishin, V., Kachanov, V., Kormilitsin, V., Levin, A., Melnik, Y., Minaev, N., Mochalov, V., Morozov, D., Nogach, L., Poslavskiy, S., Ryazantsev, A., Ryzhikov, S., Semenov, P., Shein, I., Uzunian, A., Vasiliev, A., Yakutin, A., Roy, U., Yabsley, B., Belostotski, S., Gavrilov, G., Izotov, A., Manaenkov, S., Miklukho, O., Veretennikov, D., Zhdanov, A., Bäck, T., Cederwall, B., Makonyi, K., Preston, M., Tegner, P. E., Wölbing, D., Rai, A. K., Godre, S., Calvo, D., Coli, S., De Remigis, P., Filippi, A., Giraudo, G., Lusso, S., Mazza, G., Mignone, M., Rivetti, A., Wheadon, R., Amoroso, A., Bussa, M. P., Busso, L., De Mori, F., Destefanis, M., Fava, L., Ferrero, L., Greco, M., Hu, J., Lavezzi, L., Maggiora, M., Maniscalco, G., Marcello, S., Sosio, S., Spataro, S., Balestra, F., Iazzi, F., Introzzi, R., Lavagno, A., Olave, J., Birsa, R., Bradamante, F., Bressan, A., Martin, A., Calen, H., Andersson, W. Ikegami, Johansson, T., Kupsc, A., Marciniewski, P., Papenbrock, M., Pettersson, J., Schönning, K., Wolke, M., Galnander, B., Diaz, J., Chackara, V. Pothodi, Chlopik, A., Kesik, G., Melnychuk, D., Slowinski, B., Trzcinski, A., Wojciechowski, M., Wronka, S., Zwieglinski, B., Bühler, P., Marton, J., Steinschaden, D., Suzuki, K., Widmann, E., Zmeskal, J., and Semenov-Tian-Shansky, K. M.

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

The exclusive charmonium production process in $\bar{p}p$ annihilation with an associated $\pi^0$ meson $\bar{p}p\to J/\psi\pi^0$ is studied in the framework of QCD collinear factorization. The feasibility of measuring this reaction through the $J/\psi\to e^+e^-$ decay channel with the PANDA (AntiProton ANnihilation at DArmstadt) experiment is investigated. Simulations on signal reconstruction efficiency as well as the background rejection from various sources including the $\bar{p}p\to\pi^+\pi^-\pi^0$ and $\bar{p}p\to J/\psi\pi^0\pi^0$ reactions are performed with PandaRoot, the simulation and analysis software framework of the PANDA experiment. It is shown that the measurement can be done at PANDA with significant constraining power under the assumption of an integrated luminosity attainable in four to five months of data taking at the maximum design luminosity., Comment: 25 pages, 22 figures

Published
2016
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11. Feasibility studies of time-like proton electromagnetic form factors at PANDA at FAIR

Author

PANDA Collaboration, Singh, B., Erni, W., Krusche, B., Steinacher, M., Walford, N., Liu, B., Liu, H., Liu, Z., Shen, X., Wang, C., Zhao, J., Albrecht, M., Erlen, T., Fink, M., Heinsius, F., Held, T., Holtmann, T., Jasper, S., Keshk, I., Koch, H., Kopf, B., Kuhlmann, M., Kümmel, M., Leiber, S., Mikirtychyants, M., Musiol, P., Mustafa, A., Pelizäus, M., Pychy, J., Richter, M., Schnier, C., Schröder, T., Sowa, C., Steinke, M., Triffterer, T., Wiedner, U., Ball, M., Beck, R., Hammann, C., Ketzer, B., Kube, M., Mahlberg, P., Rossbach, M., Schmidt, C., Schmitz, R., Thoma, U., Urban, M., Walther, D., Wendel, C., Wilson, A., Bianconi, A., Bragadireanu, M., Caprini, M., Pantea, D., Patel, B., Czyzycki, W., Domagala, M., Filo, G., Jaworowski, J., Krawczyk, M., Lisowski, F., Lisowski, E., Michałek, M., Poznański, P., Płażek, J., Korcyl, K., Kozela, A., Kulessa, P., Lebiedowicz, P., Pysz, K., Schäfer, W., Szczurek, A., Fiutowski, T., Idzik, M., Mindur, B., Przyborowski, D., Swientek, K., Biernat, J., Kamys, B., Kistryn, S., Korcyl, G., Krzemien, W., Magiera, A., Moskal, P., Pyszniak, A., Rudy, Z., Salabura, P., Smyrski, J., Strzempek, P., Wronska, A., Augustin, I., Böhm, R., Lehmann, I., Marinescu, D. Nicmorus, Schmitt, L., Varentsov, V., Al-Turany, M., Belias, A., Deppe, H., Dzhygadlo, R., Ehret, A., Flemming, H., Gerhardt, A., Götzen, K., Gromliuk, A., Gruber, L., Karabowicz, R., Kliemt, R., Krebs, M., Kurilla, U., Lehmann, D., Löchner, S., Lühning, J., Lynen, U., Orth, H., Patsyuk, M., Peters, K., Saito, T., Schepers, G., Schmidt, C. J., Schwarz, C., Schwiening, J., Täschner, A., Traxler, M., Ugur, C., Voss, B., Wieczorek, P., Wilms, A., Zühlsdorf, M., Abazov, V., Alexeev, G., Arefiev, V. A., Astakhov, V., Barabanov, M. Yu., Batyunya, B. V., Davydov, Y., Dodokhov, V. Kh., Efremov, A., Fechtchenko, A., Fedunov, A. G., Galoyan, A., Grigoryan, S., Koshurnikov, E. K., Lobanov, Y. Yu., Lobanov, V. I., Makarov, A. F., Malinina, L. V., Malyshev, V., Olshevskiy, A. G., Perevalova, E., Piskun, A. A., Pocheptsov, T., Pontecorvo, G., Rodionov, V., Rogov, Y., Salmin, R., Samartsev, A., Sapozhnikov, M. G., Shabratova, G., Skachkov, N. B., Skachkova, A. N., Strokovsky, E. A., Suleimanov, M., Teshev, R., Tokmenin, V., Uzhinsky, V., Vodopianov, A., Zaporozhets, S. A., Zhuravlev, N. I., Zorin, A. G., Branford, D., Glazier, D., Watts, D., Böhm, M., Britting, A., Eyrich, W., Lehmann, A., Pfaffinger, M., Uhlig, F., Dobbs, S., Seth, K., Tomaradze, A., Xiao, T., Bettoni, D., Carassiti, V., Ramusino, A. Cotta, Dalpiaz, P., Drago, A., Fioravanti, E., Garzia, I., Savrie, M., Akishina, V., Kisel, I., Kozlov, G., Pugach, M., Zyzak, M., Gianotti, P., Guaraldo, C., Lucherini, V., Bersani, A., Bracco, G., Macri, M., Parodi, R. F., Biguenko, K., Brinkmann, K., Di Pietro, V., Diehl, S., Dormenev, V., Drexler, P., Düren, M., Etzelmüller, E., Galuska, M., Gutz, E., Hahn, C., Hayrapetyan, A., Kesselkaul, M., Kühn, W., Kuske, T., Lange, J. S., Liang, Y., Metag, V., Nanova, M., Nazarenko, S., Novotny, R., Quagli, T., Reiter, S., Rieke, J., Rosenbaum, C., Schmidt, M., Schnell, R., Stenzel, H., Thöring, U., Ullrich, M., Wagner, M. N., Wasem, T., Wohlfahrt, B., Zaunick, H., Ireland, D., Rosner, G., Seitz, B., Deepak, P. N., Kulkarni, A., Apostolou, A., Babai, M., Kavatsyuk, M., Lemmens, P. J., Lindemulder, M., Loehner, H., Messchendorp, J., Schakel, P., Smit, H., Tiemens, M., van der Weele, J. C., Veenstra, R., Vejdani, S., Dutta, K., Kalita, K., Kumar, A., Roy, A., Sohlbach, H., Bai, M., Bianchi, L., Büscher, M., Cao, L., Cebulla, A., Dosdall, R., Gillitzer, A., Goldenbaum, F., Grunwald, D., Herten, A., Hu, Q., Kemmerling, G., Kleines, H., Lehrach, A., Nellen, R., Ohm, H., Orfanitski, S., Prasuhn, D., Prencipe, E., Pütz, J., Ritman, J., Schadmand, S., Sefzick, T., Serdyuk, V., Sterzenbach, G., Stockmanns, T., Wintz, P., Wüstner, P., Xu, H., Zambanini, A., Li, S., Li, Z., Sun, Z., Rigato, V., Isaksson, L., Achenbach, P., Corell, O., Denig, A., Distler, M., Hoek, M., Karavdina, A., Lauth, W., Merkel, H., Müller, U., Pochodzalla, J., Sanchez, S., Schlimme, S., Sfienti, C., Thiel, M., Ahmadi, H., Ahmed, S., Bleser, S., Capozza, L., Cardinali, M., Dbeyssi, A., Deiseroth, M., Feldbauer, F., Fritsch, M., Fröhlich, B., Jasinski, P., Kang, D., Khaneft, D., Klasen, R., Leithoff, H. H., Lin, D., Maas, F., Maldaner, S., Marta, M., Michel, M., Espí, M. C. Mora, Morales, C. Morales, Motzko, C., Nerling, F., Noll, O., Pflüger, S., Pitka, A., Piñeiro, D. Rodríguez, Sanchez-Lorente, A., Steinen, M., Valente, R., Weber, T., Zambrana, M., Zimmermann, I., Fedorov, A., Korjik, M., Missevitch, O., Boukharov, A., Malyshev, O., Marishev, I., Balanutsa, V., Balanutsa, P., Chernetsky, V., Demekhin, A., Dolgolenko, A., Fedorets, P., Gerasimov, A., Goryachev, V., Chandratre, V., Datar, V., Dutta, D., Jha, V., Kumawat, H., Mohanty, A. K., Parmar, A., Roy, B., Sonika, G., Fritzsch, C., Grieser, S., Hergemöller, A., Hetz, B., Hüsken, N., Khoukaz, A., Wessels, J. P., Khosonthongkee, K., Kobdaj, C., Limphirat, A., Srisawad, P., Yan, Y., Barnyakov, M., Barnyakov, A. Yu., Beloborodov, K., Blinov, A. E., Blinov, V. E., Bobrovnikov, V. S., Kononov, S., Kravchenko, E. A., Kuyanov, I. A., Martin, K., Onuchin, A. P., Serednyakov, S., Sokolov, A., Tikhonov, Y., Atomssa, E., Kunne, R., Marchand, D., Ramstein, B., van de Wiele, J., Wang, Y., Boca, G., Costanza, S., Genova, P., Montagna, P., Rotondi, A., Abramov, V., Belikov, N., Bukreeva, S., Davidenko, A., Derevschikov, A., Goncharenko, Y., Grishin, V., Kachanov, V., Kormilitsin, V., Levin, A., Melnik, Y., Minaev, N., Mochalov, V., Morozov, D., Nogach, L., Poslavskiy, S., Ryazantsev, A., Ryzhikov, S., Semenov, P., Shein, I., Uzunian, A., Vasiliev, A., Yakutin, A., Tomasi-Gustafsson, E., Roy, U., Yabsley, B., Belostotski, S., Gavrilov, G., Izotov, A., Manaenkov, S., Miklukho, O., Veretennikov, D., Zhdanov, A., Makonyi, K., Preston, M., Tegner, P., Wölbing, D., Bäck, T., Cederwall, B., Rai, A. K., Godre, S., Calvo, D., Coli, S., De Remigis, P., Filippi, A., Giraudo, G., Lusso, S., Mazza, G., Mignone, M., Rivetti, A., Wheadon, R., Balestra, F., Iazzi, F., Introzzi, R., Lavagno, A., Olave, J., Amoroso, A., Bussa, M. P., Busso, L., De Mori, F., Destefanis, M., Fava, L., Ferrero, L., Greco, M., Hu, J., Lavezzi, L., Maggiora, M., Maniscalco, G., Marcello, S., Sosio, S., Spataro, S., Birsa, R., Bradamante, F., Bressan, A., Martin, A., Calen, H., Andersson, W. Ikegami, Johansson, T., Kupsc, A., Marciniewski, P., Papenbrock, M., Pettersson, J., Schönning, K., Wolke, M., Galnander, B., Diaz, J., Chackara, V. Pothodi, Chlopik, A., Kesik, G., Melnychuk, D., Slowinski, B., Trzcinski, A., Wojciechowski, M., Wronka, S., Zwieglinski, B., Bühler, P., Marton, J., Steinschaden, D., Suzuki, K., Widmann, E., and Zmeskal, J.

Subjects
High Energy Physics - Experiment, Nuclear Experiment
Abstract

Simulation results for future measurements of electromagnetic proton form factors at \PANDA (FAIR) within the PandaRoot software framework are reported. The statistical precision with which the proton form factors can be determined is estimated. The signal channel $\bar p p \to e^+ e^-$ is studied on the basis of two different but consistent procedures. The suppression of the main background channel, $\textit{i.e.}$ $\bar p p \to \pi^+ \pi^-$, is studied. Furthermore, the background versus signal efficiency, statistical and systematical uncertainties on the extracted proton form factors are evaluated using two different procedures. The results are consistent with those of a previous simulation study using an older, simplified framework. However, a slightly better precision is achieved in the PandaRoot study in a large range of momentum transfer, assuming the nominal beam conditions and detector performance.

Published
2016

12. Controlled Experiments for Word Embeddings

Author

Wilson, Benjamin J. and Schakel, Adriaan M. J.

Subjects
Computer Science - Computation and Language, 68T50, I.2.7
Abstract

An experimental approach to studying the properties of word embeddings is proposed. Controlled experiments, achieved through modifications of the training corpus, permit the demonstration of direct relations between word properties and word vector direction and length. The approach is demonstrated using the word2vec CBOW model with experiments that independently vary word frequency and word co-occurrence noise. The experiments reveal that word vector length depends more or less linearly on both word frequency and the level of noise in the co-occurrence distribution of the word. The coefficients of linearity depend upon the word. The special point in feature space, defined by the (artificial) word with pure noise in its co-occurrence distribution, is found to be small but non-zero., Comment: Chagelog: Rerun experiment with subsampling turned off; re-interpreted results in light of Schnabel et al. (2015). 15 pages

Published
2015

13. Measuring Word Significance using Distributed Representations of Words

Author

Schakel, Adriaan M. J. and Wilson, Benjamin J.

Subjects
Computer Science - Computation and Language
Abstract

Distributed representations of words as real-valued vectors in a relatively low-dimensional space aim at extracting syntactic and semantic features from large text corpora. A recently introduced neural network, named word2vec (Mikolov et al., 2013a; Mikolov et al., 2013b), was shown to encode semantic information in the direction of the word vectors. In this brief report, it is proposed to use the length of the vectors, together with the term frequency, as measure of word significance in a corpus. Experimental evidence using a domain-specific corpus of abstracts is presented to support this proposal. A useful visualization technique for text corpora emerges, where words are mapped onto a two-dimensional plane and automatically ranked by significance., Comment: 7 pages, 6 figures

Published
2015

14. Differential Placental DNA Methylation of NR3C1 in Extremely Preterm Infants With Poorer Neurological Functioning

Author

Nienke H. van Dokkum, Sofia Bachini, Rikst Nynke Verkaik-Schakel, Dyvonne H. Baptist, Sahar Salavati, Karianne E. Kraft, Sicco A. Scherjon, Arend F. Bos, and Torsten Plösch

Subjects
placenta, DNA methylation, stress, prematurity, neurological functioning, Pediatrics, RJ1-570
Abstract

BackgroundUnderstanding underlying mechanisms of neurodevelopmental impairment following preterm birth may enhance opportunities for targeted interventions. We aimed to assess whether placental DNA methylation of selected genes affected early neurological functioning in preterm infants.MethodsWe included 43 infants, with gestational age

Published
2022
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15. Experimental access to Transition Distribution Amplitudes with the \={P}ANDA experiment at FAIR

Author

PANDA Collaboration, Singh, B. P., Erni, W., Keshelashvili, I., Krusche, B., M. Steinacher, Liu, B., Liu, H., Liu, Z., Shen, X., Wang, C., J. Zhao, Albrecht, M., Fink, M., Heinsius, F. H., Held, T., Holtmann, T., Koch, H., Kopf, B., Kümmel, M., Kuhl, G., Kuhlmann, M., Leyhe, M., Mikirtychyants, M., Musiol, P., Mustafa, A., Pelizäus, M., Pychy, J., Richter, M., Schnier, C., Schröder, T., Sowa, C., Steinke, M., Triffterer, T., Wiedner, U., Beck, R., Hammann, C., Kaiser, D., Ketzer, B., Kube, M., Mahlberg, P., Rossbach, M., Schmidt, C., Schmitz, R., Thoma, U., Walther, D., Wendel, C., Wilson, A., Bianconi, A., Bragadireanu, M., Caprini, M., Pantea, D., Pietreanu, D., Vasile, M. E., Patel, B., Kaplan, D., Brandys, P., Czyzewski, T., Czyzycki, W., Domagala, M., Hawryluk, M., Filo, G., Krawczyk, M., Kwiatkowski, D., Lisowski, E., Lisowski, F., Fiutowski, T., Idzik, M., Mindur, B., Przyborowski, D., Swientek, K., Czech, B., Kliczewski, S., Korcyl, K., Kozela, A., Kulessa, P., Lebiedowicz, P., Malgorzata, K., Pysz, K., Schäfer, W., Siudak, R., Szczurek, A., Biernat, J., Jowzaee, S., Kamys, B., Kistryn, S., Korcyl, G., Krzemien, W., Magiera, A., Moskal, P., Palka, M., Psyzniak, A., Rudy, Z., Salabura, P., Smyrski, J., Strzempek, P., Wrońska, A., Augustin, I., Lehmann, I., Nicmorus, D., Schepers, G., Schmitt, L., Al-Turany, M., Cahit, U., Capozza, L., Dbeyssi, A., Deppe, H., Dzhygadlo, R., Ehret, A., Flemming, H., Gerhardt, A., Götzen, K., Karabowicz, R., Kliemt, R., Kunkel, J., Kurilla, U., Lehmann, D., Lühning, J., Maas, F., Morales, C. Morales, Espí, M. C. Mora, Nerling, F., Orth, H., Peters, K., Pineiro, D. Rodríguez, Saito, N., Saito, T., Lorente, A. Sánchez, Schmidt, C. J., Schwarz, C., Schwiening, J., Traxler, M., Valente, R., Voss, B., Wieczorek, P., Wilms, A., Zühlsdorf, M., Abazov, V. M., Alexeev, G., Arefiev, A., Astakhov, V. I., Barabanov, M. Yu., Batyunya, B. V., Davydov, Yu. I., Dodokhov, V. Kh., Efremov, A. A., Fedunov, A. G., Festchenko, A. A., Galoyan, A. S., Grigoryan, S., Karmokov, A., Koshurnikov, E. K., Lobanov, V. I., Lobanov, Yu. Yu., Makarov, A. F., Malinina, L. V., Malyshev, V. L., Mustafaev, G. A., Olshevskiy, A., Pasyuk, M. A., Perevalova, E. A., Piskun, A. A., Pocheptsov, T. A., Pontecorvo, G., Rodionov, V. K., Rogov, Yu. N., Salmin, R. A., Samartsev, A. G., Sapozhnikov, M. G., Shabratova, G. S., Skachkov, N. B., Skachkova, A. N., Strokovsky, E. A., Suleimanov, M. K., Teshev, R. Sh., Tokmenin, V. V., Uzhinsky, V. V., Vodopyanov, A. S., Zaporozhets, S. A., Zhuravlev, N. I., Zorin, A. G., Branford, D., Glazier, D., Watts, D., Woods, P., Britting, A., Eyrich, W., Lehmann, A., Uhlig, F., Dobbs, S., Seth, K., Tomaradze, A., Xiao, T., Bettoni, D., Carassiti, V., Ramusino, A. Cotta, Dalpiaz, P., Drago, A., Fioravanti, E., Garzia, I., Savriè, M., Stancari, G., Akishina, V., Kisel, I., Kulakov, I., Zyzak, M., Arora, R., Bel, T., Gromliuk, A., Kalicy, G., Krebs, M., Patsyuk, M., Zuehlsdorf, M., Bianchi, N., Gianotti, P., Guaraldo, C., Lucherini, V., Pace, E., Bersani, A., Bracco, G., Macri, M., Parodi, R. F., Bianco, S., Bremer, D., Brinkmann, K. T., Diehl, S., Dormenev, V., Drexler, P., Düren, M., Eissner, T., Etzelmüller, E., Föhl, K., Galuska, M., Gessler, T., Gutz, E., Hayrapetyan, A., Hu, J., Kröck, B., Kühn, W., Kuske, T., Lange, S., Liang, Y., Merle, O., Metag, V., Mülhheim, D., Münchow, D., Nanova, M., Novotny, R., Pitka, A., Quagli, T., Rieke, J., Rosenbaum, C., Schnell, R., Spruck, B., Stenzel, H., Thöring, U., Ullrich, M., Wasem, T., Werner, M., Zaunick, H. G., Ireland, D., Rosner, G., Seitz, B., Deepak, P. N., Kulkarni, A. V., Apostolou, A., Babai, M., Kavatsyuk, M., Lemmens, P., Lindemulder, M., Löhner, H., Messchendorp, J., Schakel, P., Smit, H., van der Weele, J. C., Tiemens, M., Veenstra, R., Vejdani, S., Kalita, K., Mohanta, D. P., Kumar, A., Roy, A., Sahoo, R., Sohlbach, H., Büscher, M., Cao, L., Cebulla, A., Deermann, D., Dosdall, R., Esch, S., Georgadze, I., Gillitzer, A., Goerres, A., Goldenbaum, F., Grunwald, D., Herten, A., Hu, Q., Kemmerling, G., Kleines, H., Kozlov, V., Lehrach, A., Leiber, S., Maier, R., Nellen, R., Ohm, H., Orfanitski, S., Prasuhn, D., Prencipe, E., Ritman, J., Schadmand, S., Schumann, J., Sefzick, T., Serdyuk, V., Sterzenbach, G., Stockmanns, T., Wintz, P., Wüstner, P., Xu, H., Li, S., Li, Z., Sun, Z., Rigato, V., Fissum, S., Hansen, K., Isaksson, L., Lundin, M., Schröder, B., Achenbach, P., Bleser, S., Cardinali, M., Corell, O., Deiseroth, M., Denig, A., Distler, M., Feldbauer, F., Fritsch, M., Jasinski, P., Hoek, M., Kangh, D., Karavdina, A., Lauth, W., Leithoff, H., Merkel, H., Michel, M., Motzko, C., Müller, U., Noll, O., Plueger, S., Pochodzalla, J., Sanchez, S., Schlimme, S., Sfienti, C., Steinen, M., Thiel, M., Weber, T., Zambrana, M., Dormenev, V. I., Fedorov, A. A., Korzihik, M. V., Missevitch, O. V., Balanutsa, P., Balanutsa, V., Chernetsky, V., Demekhin, A., Dolgolenko, A., Fedorets, P., Gerasimov, A., Goryachev, V., Varentsov, V., Boukharov, A., Malyshev, O., Marishev, I., Semenov, A., Konorov, I., Paul, S., Grieser, S., Hergemöller, A. K., Khoukaz, A., Köhler, E., Täschner, A., Wessels, J., Dash, S., Jadhav, M., Kumar, S., Sarin, P., Varma, R., Chandratre, V. B., Datar, V., Dutta, D., Jha, V., Kumawat, H., Mohanty, A. K., Roy, B., Yan, Y., Chinorat, K., Khanchai, K., Ayut, L., Pornrad, S., Barnyakov, A. Y., Blinov, A. E., Blinov, V. E., Bobrovnikov, V. S., Kononov, S. A., Kravchenko, E. A., Kuyanov, I. A., Onuchin, A. P., Sokolov, A. A., Tikhonov, Y. A., Atomssa, E., Hennino, T., Imre, M., Kunne, R., Galliard, C. Le, Ma, B., Marchand, D., Ong, S., Ramstein, B., Rosier, P., Tomasi-Gustafsson, E., Van de Wiele, J., Boca, G., Costanza, S., Genova, P., Lavezzi, L., Montagna, P., Rotondi, A., Abramov, V., Belikov, N., Bukreeva, S., Davidenko, A., Derevschikov, A., Goncharenko, Y., Grishin, V., Kachanov, V., Kormilitsin, V., Melnik, Y., Levin, A., Minaev, N., Mochalov, V., Morozov, D., Nogach, L., Poslavskiy, S., Ryazantsev, A., Ryzhikov, S., Semenov, P., Shein, I., Uzunian, A., Vasiliev, A., Yakutin, A., Yabsley, B., Bäck, T., Cederwall, B., Makónyi, K., Tegnér, P. E., von Würtemberg, K. M., Belostotski, S., Gavrilov, G., Izotov, A., Kashchuk, A., Levitskaya, O., Manaenkov, S., Miklukho, O., Naryshkin, Y., Suvorov, K., Veretennikov, D., Zhadanov, A., Rai, A. K., Godre, S. S., Duchat, R., Amoroso, A., Bussa, M. P., Busso, L., De Mori, F., Destefanis, M., Fava, L., Ferrero, L., Greco, M., Maggiora, M., Maniscalco, G., Marcello, S., Sosio, S., Spataro, S., Zotti, L., Calvo, D., Coli, S., De Remigis, P., Filippi, A., Giraudo, G., Lusso, S., Mazza, G., Mingnore, M., Rivetti, A., Wheadon, R., Balestra, F., Iazzi, F., Introzzi, R., Lavagno, A., Younis, H., Birsa, R., Bradamante, F., Bressan, A., Martin, A., Clement, H., Gålnander, B., Balkeståhl, L. Caldeira, Calén, H., Fransson, K., Johansson, T., Kupsc, A., Marciniewski, P., Pettersson, J., Schönning, K., Wolke, M., Zlomanczuk, J., Díaz, J., Ortiz, A., Vinodkumar, P. C., Parmar, A., Chlopik, A., Melnychuk, D., Slowinski, B., Trzcinski, A., Wojciechowski, M., Wronka, S., Zwieglinski, B., Bühler, P., Marton, J., Suzuki, K., Widmann, E., Zmeskal, J., Fröhlich, B., Khaneft, D., Lin, D., Zimmermann, I., and Semenov-Tian-Shansky, K.

Subjects
High Energy Physics - Experiment, High Energy Physics - Phenomenology, Nuclear Experiment
Abstract

Baryon-to-meson Transition Distribution Amplitudes (TDAs) encoding valuable new information on hadron structure appear as building blocks in the collinear factorized description for several types of hard exclusive reactions. In this paper, we address the possibility of accessing nucleon-to-pion ($\pi N$) TDAs from $\bar{p}p \to e^+e^- \pi^0$ reaction with the future \={P}ANDA detector at the FAIR facility. At high center of mass energy and high invariant mass squared of the lepton pair $q^2$, the amplitude of the signal channel $\bar{p}p \to e^+e^- \pi^0$ admits a QCD factorized description in terms of $\pi N$ TDAs and nucleon Distribution Amplitudes (DAs) in the forward and backward kinematic regimes. Assuming the validity of this factorized description, we perform feasibility studies for measuring $\bar{p}p \to e^+e^- \pi^0$ with the \={P}ANDA detector. Detailed simulations on signal reconstruction efficiency as well as on rejection of the most severe background channel, i.e. $\bar{p}p \to \pi^+\pi^- \pi^0$ were performed for the center of mass energy squared $s = 5$ GeV$^2$ and $s = 10$ GeV$^2$, in the kinematic regions $3.0 < q^2 < 4.3$ GeV$^2$ and $5 < q^2 < 9$ GeV$^2$, respectively, with a neutral pion scattered in the forward or backward cone $| \cos\theta_{\pi^0}| > 0.5 $ in the proton-antiproton center of mass frame. Results of the simulation show that the particle identification capabilities of the \={P}ANDA detector will allow to achieve a background rejection factor of $5\cdot 10^7$ ($1\cdot 10^7$) at low (high) $q^2$ for $s=5$ GeV$^2$, and of $1\cdot 10^8$ ($6\cdot 10^6$) at low (high) $q^2$ for $s=10$ GeV$^2$, while keeping the signal reconstruction efficiency at around $40\%$. At both energies, a clean lepton signal can be reconstructed with the expected statistics corresponding to $2$ fb$^{-1}$ of integrated luminosity. (.../...), Comment: 19 pages, 7 figures (some multiple), 2 tables (each double), preprint of an article for epj - v2

Published
2014

16. Critical Line of the O($N$) Loop Model on the Square Lattice

Author

Silva, Antônio Márcio P., Schakel, Adriaan M. J., and Vasconcelos, Giovani L.

Subjects
Condensed Matter - Statistical Mechanics
Abstract

An efficient algorithm is presented to simulate the O(N) loop model on the square lattice for arbitrary values of $N>0$. The scheme combines the worm algorithm with a new data structure to resolve both the problem of loop crossings and the necessity of counting the number of loops at each Monte Carlo update. With the use of this scheme, the line of critical points (and other properties) of the O($N$) model on the square lattice for $0

Published
2013
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17. Vortex motion around a circular cylinder

Author

Vasconcelos, G. L., Moura, M. N., and Schakel, A. M. J.

Subjects
Physics - Fluid Dynamics
Abstract

The motion of a pair of counter-rotating point vortices placed in a uniform flow around a circular cylinder forms a rich nonlinear system that is often used to model vortex shedding. The phase portrait of the Hamiltonian governing the dynamics of a vortex pair that moves symmetrically with respect to the centerline---a case that can be realized experimentally by placing a splitter plate in the center plane---is presented. The analysis provides new insights and reveals novel dynamical features of the system, such as a nilpotent saddle point at infinity whose homoclinic orbits define the region of nonlinear stability of the so-called F\"oppl equilibrium. It is pointed out that a vortex pair properly placed downstream can overcome the cylinder and move off to infinity upstream. In addition, the nonlinear dynamics resulting from antisymmetric perturbations of the F\"oppl equilibrium is studied and its relevance to vortex shedding discussed., Comment: 21 pages, 6 figures

Published
2012
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18. Technical Design Report for the: PANDA Straw Tube Tracker

Author

PANDA Collaboration, Erni, W., Keshelashvili, I., Krusche, B., Steinacher, M., Heng, Y., Liu, Z., Liu, H., Shen, X., Wang, Q., Xu, H., Aab, A., Albrecht, M., Becker, J., Csapó, A., Feldbauer, F., Fink, M., Friedel, P., Heinsius, F. H., Held, T., Klask, L., Koch, H., Kopf, B., Leiber, S., Leyhe, M., Motzko, C., Pelizäus, M., Pychy, J., Roth, B., Schröder, T., Schulze, J., Sowa, C., Steinke, M., Trifterer, T., Wiedner, U., Zhong, J., Beck, R., Bianco, S., Brinkmann, K. T., Hammann, C., Hinterberger, F., Kaiser, D., Kliemt, R., Kube, M., Pitka, A., Quagli, T., Schmidt, C., Schmitz, R., Schnell, R., Thoma, U., Vlasov, P., Walther, D., Wendel, C., Würschig, T., Zaunick, H. G., Bianconi, A., Bragadireanu, M., Caprini, M., Pantea, D., Pantelica, D., Pietreanu, D., Serbina, L., Tarta, P. D., Kaplan, D., Fiutowski, T., Idzik, M., Mindur, B., Przyborowski, D., Swientek, K., Czech, B., Kistryn, M., Kliczewski, S., Kozela, A., Kulessa, P., Lebiedowicz, P., Pysz, K., Schäfer, W., Siudak, R., Szczurek, A., Jowzaee, S., Kajetanowicz, M., Kamys, B., Kistryn, S., Korcyl, G., Korcyl, K., Krzemien, W., Magiera, A., Moskal, P., Palka, M., Rudy, Z., Salabura, P., Smyrski, J., Wrońska, A., Augustin, I., Lehmann, I., Nimorus, D., Schepers, G., Al-Turany, M., Arora, R., Deppe, H., Flemming, H., Gerhardt, A., Götzen, K., Jordi, A. F., Kalicy, G., Karabowicz, R., Lehmann, D., Lewandowski, B., Lühning, J., Maas, F., Orth, H., Patsyuk, M., Peters, K., Saito, T., Schmidt, C. J., Schmitt, L., Schwarz, C., Schwiening, J., Traxler, M., Voss, B., Wieczorek, P., Wilms, A., Zühlsdorf, M., Abazov, V. M., Alexeev, G., Arefiev, A., Astakhov, V. I., Barabanov, M. Yu., Batyunya, B. V., Davydov, Yu. I., Dodokhov, V. Kh., Efremov, A. A., Fedunov, A. G., Festchenko, A. A., Galoyan, A. S., Grigoryan, S., Karmokov, A., Koshurnikov, E. K., Lobanov, V. I., Lobanov, Yu. Yu., Makarov, A. F., Malinina, L. V., Malyshev, V. L., Mustafaev, G. A., Olshevskiy, A., Pasyuk, M. A., Perevalova, E. A., Piskun, A. A., Pocheptsov, T. A., Pontecorvo, G., Rodionov, V. K., Rogov, Yu. N., Salmin, R. A., Samartsev, A. G., Sapozhnikov, M. G., Shabratova, G. S., Skachkova, A. N., Skachkov, N. B., Strokovsky, E. A., Suleimanov, M. K., Teshev, R. Sh., Tokmenin, V. V., Uzhinsky, V. V., Vodopyanov, A. S., Zaporozhets, S. A., Zhuravlev, N. I., Zorin, A. G., Branford, D., Glazier, D., Watts, D., Woods, P., Britting, A., Eyrich, W., Lehmann, A., Uhlig, F., Dobbs, S., Metreveli, Z., Seth, K., Tomaradze, A., Xiao, T., Bettoni, D., Carassiti, V., Ramusino, A. Cotta, Dalpiaz, P., Drago, A., Fioravanti, E., Garzia, I., Savriè, M., Stancari, G., Bianchi, N., Gianotti, P., Guaraldo, C., Lucherini, V., Orecchini, D., Pace, E., Bersani, A., Bracco, G., Macri, M., Parodi, R. F., Bremer, D., Dormenev, V., Drexler, P., Düren, M., Eissner, T., Föhl, K., Galuska, M., Gessler, T., Hayrapetyan, A., Hu, J., Koch, P., Kröck, B., Kühn, W., Lange, S., Liang, Y., Merle, O., Metag, V., Moritz, M., Münchow, D., Nanova, M., Novotny, R., Spruck, B., Stenzel, H., Ullrich, T., Werner, M., Euan, C., Hoek, M., Ireland, D., Keri, T., Montgomery, R., Protopopescu, D., Rosner, G., Seitz, B., Babai, M., Glazenborg-Kluttig, A., Kavatsyuk, M., Lemmens, P., Lindemulder, M., Löhner, H., Messchendorp, J., Moeini, H., Schakel, P., Schreuder, F., Smit, H., Tambave, G., van der Weele, J. C., Veenstra, R., Sohlbach, H., Büscher, M., Deermann, D., Dosdall, R., Esch, S., Gillitzer, A., Goldenbaum, F., Grunwald, D., Henssler, S., Herten, A., Hu, Q., Kemmerling, G., Kleines, H., Kozlov, V., Lehrach, A., Maier, R., Mertens, M., Ohm, H., Orfanitski, S., Prasuhn, D., Randriamalala, T., Ritman, J., Schadmand, S., Serdyuk, V., Sterzenbach, G., Stockmanns, T., Wintz, P., Wüstner, P., Kisiel, J., Li, S., Li, Z., Sun, Z., Rigato, V., Fissum, S., Hansen, K., Isaksson, L., Lundin, M., Schröder, B., Achenbach, P., Bleser, S., Cahit, U., Cardinali, M., Denig, A., Distler, M., Fritsch, M., Kangh, D., Karavdina, A., Lauth, W., Merkel, H., Michel, M., Espi, M. C. Mora, Müller, U., Pochodzalla, J., Prometeusz, J., Sanchez, S., Sanchez-Lorente, A., Schlimme, S., Sfienti, C., Thiel, M., Weber, T., Dormenev, V. I., Fedorov, A. A., Korzhik, M. V., Missevitch, O. V., Balanutsa, V., Chernetsky, V., Demekhin, A., Dolgolenko, A., Fedorets, P., Gerasimov, A., Goryachev, V., Varentsov, V., Boukharov, A., Malyshev, O., Marishev, I., Semenov, A., Böhmer, F., Dørheim, S., Ketzer, B., Paul, S., Hergemöller, A. K., Khoukaz, A., Köhler, E., Täschner, A., Wessels, J., Varma, R., Chaterjee, A., Jha, V., Kailas, S., Roy, B., Yan, Y., Chinorat, K., Khanchai, K., Ayut, L., Pomrad, S., Baldin, E., Kotov, K., Peleganchuk, S., Tikhonov, Yu., Boucher, J., Chambert, V., Dbeyssi, A., Hennino, T., Imre, M., Kunne, R., Galliard, C. Le, Ma, B., Marchand, D., Maroni, A., Ong, S., Ramstein, B., Rosier, P., Sudol, M., Tomasi-Gustafsson, E., Van de Wiele, J., Boca, G., Braghieri, A., Costanza, S., Genova, P., Lavezzi, L., Montagna, P., Rotondi, A., Abramov, V., Belikov, N., Davidenko, A., Derevschikov, A., Goncharenko, Y., Grishin, V., Kachanov, V., Konstantinov, D., Kormilitsin, V., Melnik, Y., Levin, A., Minaev, N., Mochalov, V., Morozov, D., Nogach, L., Poslavskiy, S., Ryazantsev, A., Ryzhikov, S., Semenov, P., Shein, I., Uzunian, A., Vasiliev, A., Yakutin, A., Bäck, T., Cederwall, B., Makónyi, K., Tegnér, P. E., von Würtemberg, K. M., Belostotski, S., Gavrilov, G., Itzotov, A., Kashchuk, A., Kisselev, A., Kravchenko, P., Levitskaya, O., Manaenkov, S., Miklukho, O., Naryshkin, Y., Veretennikov, D., Vikhrov, V., Zhadanov, A., Alberto, D., Amoroso, A., Bussa, M. P., Busso, L., De Mori, F., Destefanis, M., Fava, L., Ferrero, L., Greco, M., Maggiora, M., Marcello, S., Sosio, S., Spataro, S., Zotti, L., Calvo, D., Coli, S., De Remigis, P., Filippi, A., Giraudo, G., Lusso, S., Mazza, G., Morra, O., Rivetti, A., Wheadon, R., Iazzi, F., Lavagno, A., Younis, H., Birsa, R., Bradamante, F., Bressan, A., Martin, A., Clement, H., Galander, B., Balkeståhl, L. Caldeira, Calén, H., Fransson, K., Johansson, T., Kupsc, A., Marciniewski, P., Thomé, E., Wolke, M., Zlomanczuk, J., Díaz, J., Ortiz, A., Dmowski, K., Duda, P., Korzeniewski, R., Slowinski, B., Chlopik, A., Guzik, Z., Kosinski, K., Melnychuk, D., Wasilewski, A., Wojciechowski, M., Wronka, S., Wysocka, A., Zwieglinski, B., Bühler, P., Hartman, O., Kienle, P., Marton, J., Suzuki, K., Widmann, E., and Zmeskal, J.

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

This document describes the technical layout and the expected performance of the Straw Tube Tracker (STT), the main tracking detector of the PANDA target spectrometer. The STT encloses a Micro-Vertex-Detector (MVD) for the inner tracking and is followed in beam direction by a set of GEM-stations. The tasks of the STT are the measurement of the particle momentum from the reconstructed trajectory and the measurement of the specific energy-loss for a particle identification. Dedicated simulations with full analysis studies of certain proton-antiproton reactions, identified as being benchmark tests for the whole PANDA scientific program, have been performed to test the STT layout and performance. The results are presented, and the time lines to construct the STT are described., Comment: accepted for publication on EPJA

Published
2012
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19. Tan Relations in Dilute Bose Gasses

Author

Schakel, Adriaan M. J.

Subjects
Condensed Matter - Quantum Gases
Abstract

The exact relations for strongly interacting Fermi gasses, recently derived by Tan, are shown to first order in the loop expansion to also apply to dilute Bose gasses. A simple thermodynamic argument is put forward to support their validity. As an application, the second-order correction to the depletion of the condensate is determined to logarithmic accuracy., Comment: 4 pages, no figures

Published
2010

20. Holographic interpretation of two-dimensional O(N) models coupled to quantum gravity

Author

Janke, Wolfhard and Schakel, Adriaan M. J.

Subjects
Condensed Matter - Statistical Mechanics, High Energy Physics - Theory
Abstract

Various two-dimensional O(N) models coupled to Euclidean quantum gravity, whose intrinsic dimension is four, are shown to belong to universality classes of nongravitating statistical models in a lower number of dimensions. It is speculated that the matching critical behaviors in the gravitating and dimensionally reduced models may be manifestations of the holographic principle., Comment: 12 pages, 1 figure

Published
2010

21. Derivation of the effective action of a dilute Fermi gas in the unitary limit of the BCS-BEC crossover

Author

Schakel, Adriaan M. J.

Subjects
Condensed Matter - Quantum Gases
Abstract

The effective action describing the gapless Nambu-Goldstone, or Anderson-Bogoliubov, mode of a zero-temperature dilute Fermi gas at unitarity is derived up to next-to-leading order in derivatives from the microscopic theory. Apart from a next-to-leading order term that is suppressed in the BCS limit, the effective action obtained in the strong-coupling unitary limit is proportional to that in the weak-coupling BCS limit., Comment: 13 pages, no figures; v2: discussion of one-dimensional system and references added

Published
2009
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22. Critical Loop Gases and the Worm Algorithm

Author

Janke, Wolfhard, Neuhaus, Thomas, and Schakel, Adriaan M. J.

Subjects
Condensed Matter - Statistical Mechanics, High Energy Physics - Lattice
Abstract

The loop gas approach to lattice field theory provides an alternative, geometrical description in terms of fluctuating loops. Statistical ensembles of random loops can be efficiently generated by Monte Carlo simulations using the worm update algorithm. In this paper, concepts from percolation theory and the theory of self-avoiding random walks are used to describe estimators of physical observables that utilize the nature of the worm algorithm. The fractal structure of the random loops as well as their scaling properties are studied. To support this approach, the O(1) loop model, or high-temperature series expansion of the Ising model, is simulated on a honeycomb lattice, with its known exact results providing valuable benchmarks., Comment: 34 pages, 12 figures; v2: 2 figures and 1 table added; v3: typo's corrected

Published
2009
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23. Geometric Properties of the Three-Dimensional Ising and XY Models

Author

Winter, Frank, Janke, Wolfhard, and Schakel, Adriaan M. J.

Subjects
Condensed Matter - Statistical Mechanics
Abstract

The fractal structure of high-temperature graphs of the three-dimensional Ising and XY models is investigated by simulating these graphs directly on a cubic lattice and analyzing them with the help of percolation observables. The Ising graphs are shown to percolate right at the Curie critical point. The diverging length scale relevant to the graphs in the vicinity of the percolation threshold is shown to be provided by the spin correlation length. The fractal dimension of the high-temperature graphs at criticality is estimated to be $D = 1.7349(65)$ for the Ising and $D = 1.7626(66)$ for the XY model., Comment: 19 pages

Published
2008
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24. Percolation of Vortices in the 3D Abelian Lattice Higgs Model

Author

Wenzel, Sandro, Bittner, Elmar, Janke, Wolfhard, and Schakel, Adriaan M. J.

Subjects
High Energy Physics - Lattice
Abstract

The compact Abelian Higgs model is simulated on a cubic lattice where it possesses vortex lines and pointlike magnetic monopoles as topological defects. The focus of this high-precision Monte Carlo study is on the vortex network, which is investigated by means of percolation observables. In the region of the phase diagram where the Higgs and confinement phases are separated by a first-order transition, it is shown that the vortices percolate right at the phase boundary, and that the first-order nature of the transition is reflected by the network. In the crossover region, where the phase boundary ceases to be first order, the vortices are shown to still percolate. In contrast to other observables, the percolation observables show finite-size scaling. The exponents characterizing the critical behavior of the vortices in this region are shown to fall in the random percolation universality class., Comment: 24 pages, 12 figures

Published
2007
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25. Two-Dimensional Critical Potts and its Tricritical Shadow

Author

Janke, Wolfhard and Schakel, Adriaan M. J.

Subjects
Condensed Matter - Statistical Mechanics
Abstract

These notes give examples of how suitably defined geometrical objects encode in their fractal structure thermal critical behavior. The emphasis is on the two-dimensional Potts model for which two types of spin clusters can be defined. Whereas the Fortuin-Kasteleyn clusters describe the standard critical behavior, the geometrical clusters describe the tricritical behavior that arises when including vacant sites in the pure Potts model. Other phase transitions that allow for a geometrical description discussed in these notes include the superfluid phase transition and Bose-Einstein condensation., Comment: 10 pages,9 figures. Contribution to the IV Brazilian Meeting on Simulational Physics (Ouro Preto, Minas Gerais, Brazil, 9 - 12 August 2005)

Published
2006
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26. Spacetime Approach to Phase Transitions

Author

Janke, Wolfhard and Schakel, Adriaan M. J.

Subjects
Condensed Matter - Statistical Mechanics, High Energy Physics - Lattice
Abstract

In these notes, the application of Feynman's sum-over-paths approach to thermal phase transitions is discussed. The paradigm of such a spacetime approach to critical phenomena is provided by the high-temperature expansion of spin models. This expansion, known as the hopping expansion in the context of lattice field theory, yields a geometric description of the phase transition in these models, with the thermal critical exponents being determined by the fractal structure of the high-temperature graphs. The graphs percolate at the thermal critical point and can be studied using purely geometrical observables known from percolation theory. Besides the phase transition in spin models and in the closely related $\phi^4$ theory, other transitions discussed from this perspective include Bose-Einstein condensation, and the transitions in the Higgs model and the pure U(1) gauge theory., Comment: 59 pages, 18 figures. Write-up of Ising Lectures presented at the National Academy of Sciences, Lviv, Ukraine, 2004. 2nd version: corrected typos

Published
2006
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27. Vortex Proliferation and the Dual Superconductor Scenario for Confinement: The 3D Compact U(1) Lattice Higgs Model

Author

Wenzel, Sandro, Bittner, Elmar, Janke, Wolfhard, Schakel, Adriaan M. J., and Schiller, Arwed

Subjects
High Energy Physics - Lattice
Abstract

It is argued that the phase diagram of the 3D Compact U(1) Lattice Higgs Model is more refined than generally thought. The confined and Higgs phases are separated by a well-defined phase boundary, marked by proliferating vortices. It is shown that the confinement mechanism at work is precisely the dual superconductor scenario., Comment: 6 pages, 2 figures, Talk presented at Lattice 2005 (Spin and Higgs Models)

Published
2005

28. Anomalous Scaling and Fractal Dimensions

Author

Janke, Wolfhard and Schakel, Adriaan M. J.

Subjects
Condensed Matter - Statistical Mechanics
Abstract

The relation between critical exponents, characterizing a continuous phase transition, and the fractal structure of physical lines, proliferating at the critical point, is established by considering the two-dimensional O($N$) spin model for which many exact results are available., Comment: 3 pages, 1 figure

Published
2005

29. Kertesz Line in the Three-Dimensional Compact U(1) Lattice Higgs Model

Author

Wenzel, Sandro, Bittner, Elmar, Janke, Wolfhard, Schakel, Adriaan M. J., and Schiller, Arwed

Subjects
Condensed Matter - Strongly Correlated Electrons, High Energy Physics - Lattice
Abstract

The three-dimensional lattice Higgs model with compact U(1) gauge symmetry and unit charge is investigated by means of Monte Carlo simulations. The full model with fluctuating Higgs amplitude is simulated, and both energy as well as topological observables are measured. The data show a Higgs and a confined phase separated by a well-defined phase boundary, which is argued to be caused by proliferating vortices. For fixed gauge coupling, the phase boundary consists of a line of first-order phase transitions at small Higgs self-coupling, ending at a critical point. The phase boundary then continues as a Kertesz line across which thermodynamic quantities are nonsingular. Symmetry arguments are given to support these findings., Comment: 4 pages, 3 figures

Published
2005
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30. Fractal Structure of High-Temperature Graphs of O($N$) Models in Two Dimensions

Author

Janke, Wolfhard and Schakel, Adriaan M. J.

Subjects
Condensed Matter - Statistical Mechanics
Abstract

The fractal structure and critical properties of the high-temperature graphs of the two-dimensional O($N)$ model close to criticality are investigated. Based on Monte Carlo simulations, De Gennes' results for polymer chains, corresponding to the limit $N \to 0$, are generalized to random loops for arbitrary $-2 \leq N \leq 2$. The loops are also studied close to their tricritical point, known as the $\Theta$ point in the context of polymers, where they collapse. The corresponding fractal dimensions are argued to be in one-to-one correspondence with those at the critical point, leading to an analytic prediction for the magnetic scaling dimension at the O($N)$ tricritical point., Comment: 4 pages, no figures; 2nd version: Introduction rewritten, comparison of prediction with recent high-precision Monte Carlo data with figure included, references added

Published
2005
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31. Anomalous Dimension of Dirac's Gauge-Invariant Nonlocal Order Parameter in Ginzburg-Landau Field Theory

Author

Kleinert, H. and Schakel, A. M. J.

Subjects
Condensed Matter - Superconductivity, Condensed Matter - Statistical Mechanics
Abstract

In a Ginzburg-Landau theory with $n$ fields, the anomalous dimension of the gauge-invariant nonlocal order parameter defined by the long-distance limit of Dirac's gauge-invariant two-point function is calculated. The result is exact for all $n$ to first order in $\epsilon \equiv 4-d$, and for all $d\in (2,4)$ to first order in $1/n$, and coincides with the previously calculated gauge-dependent exponent in the Landau gauge., Comment: Author Information under http://www.physik.fu-berlin.de/~kleinert/institution.html . Latest update of paper http://www.physik.fu-berlin.de/~kleinert/356

Published
2005
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32. DNA Methylation of TLR4, VEGFA, and DEFA5 Is Associated With Necrotizing Enterocolitis in Preterm Infants

Author

Daphne H. Klerk, Torsten Plösch, Rikst Nynke Verkaik-Schakel, Jan B. F. Hulscher, Elisabeth M. W. Kooi, and Arend F. Bos

Subjects
neonatology, DNA methylation, epigenetics, preterm infant, necrotizing enterocolitis, Toll-like receptor 4, Pediatrics, RJ1-570
Abstract

Background: Epigenetic changes, such as DNA methylation, may contribute to an increased susceptibility for developing necrotizing enterocolitis (NEC) in preterm infants. We assessed DNA methylation in five NEC-associated genes, selected from literature: EPO, VEGFA, ENOS, DEFA5, and TLR4 in infants with NEC and controls.Methods: Observational cohort study including 24 preterm infants who developed NEC (≥Bell Stage IIA) and 45 matched controls. DNA was isolated from stool samples and methylation measured using pyrosequencing. We investigated differences in methylation prior to NEC compared with controls. Next, in NEC infants, we investigated methylation patterns long before, a short time before NEC onset, and after NEC.Results: Prior to NEC, only TLR4 CpG 2 methylation was increased in NEC infants (median = 75.4%, IQR = 71.3–83.8%) versus controls (median = 69.0%, IQR = 64.5–77.4%, p = 0.025). In NEC infants, VEGFA CpG 3 methylation was 0.8% long before NEC, increasing to 1.8% a short time before NEC and 2.0% after NEC (p = 0.011; p = 0.021, respectively). A similar pattern was found in DEFA5 CpG 1, which increased from 75.4 to 81.4% and remained 85.3% (p = 0.027; p = 0.019, respectively). These changes were not present for EPO, ENOS, and TLR4.Conclusion: Epigenetic changes of TLR4, VEGFA, and DEFA5 are present in NEC infants and can differ in relation to the time of NEC onset. Differences in DNA methylation of TLR4, VEGFA, and DEFA5 may influence gene expression and increase the risk for developing NEC. This study also demonstrates the use of human DNA extraction from stool samples as a novel non-invasive method for exploring the bowel of preterm infants and which can also be used for necrotizing enterocolitis patients.

Published
2021
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33. Fractal Structure of Spin Clusters and Domain Walls in 2D Ising Model

Author

Janke, Wolfhard and Schakel, Adriaan M. J.

Subjects
Condensed Matter - Statistical Mechanics
Abstract

The fractal structure of spin clusters and their boundaries in the critical two-dimensional (2D) Ising model is investigated numerically. The fractal dimensions of these geometrical objects are estimated by means of Monte Carlo simulations on relatively small lattices through standard finite-size scaling. The obtained results are in excellent agreement with theoretical predictions and partly provide significant improvements in precision over existing numerical estimates., Comment: 8 pages, 8 figures; v2: minor changes in text, various plots are put in one figure

Published
2004
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34. Geometrical Phase Transitions

Author

Janke, Wolfhard and Schakel, Adriaan M. J.

Subjects
Condensed Matter - Statistical Mechanics
Abstract

The geometrical approach to phase transitions is illustrated by simulating the high-temperature representation of the Ising model on a square lattice., Comment: 5 pages, 3 figures, talk presented at Conference on Computational Physics 2004, Genoa, 1-4 September 2004; 2nd version: slightly expanded version

Published
2004
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35. Geometrical vs. Fortuin-Kasteleyn Clusters in the Two-Dimensional $q$-State Potts Model

Author

Janke, Wolfhard and Schakel, Adriaan M. J.

Subjects
Condensed Matter - Statistical Mechanics
Abstract

The tricritical behavior of the two-dimensional $q$-state Potts model with vacancies for $1\leq q \leq4$ is argued to be encoded in the fractal structure of the geometrical spin clusters of the pure model. The close connection between the critical properties of the pure model and the tricritical properties of the diluted model is shown to be reflected in an intimate relation between Fortuin-Kasteleyn and geometrical clusters: The same transformation mapping the two critical regimes onto each other also maps the two cluster types onto each other. The map conserves the central charge, so that both cluster types are in the same universality class. The geometrical picture is supported by a Monte Carlo simulation of the high-temperature representation of the Ising model ($q=2$). In this new numerical approach, closed graph configurations are generated by means of a Metropolis update algorithm, involving single plaquettes., Comment: 23 pages, 11 figures, 2nd version: references added, introduction partly rewritten, error estimates improved

Published
2003
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36. Zeta Function Regularization of Infrared Divergences in Bose-Einstein Condensation

Author

Schakel, Adriaan M. J.

Subjects
Condensed Matter
Abstract

The perturbative calculation of the effect of fluctuations in the nonzero frequency modes of a weakly interacting Bose gas on the condensation temperature is reviewed. These dynamic modes, discarded in most of the recent studies, have a temperature-induced energy gap that allows for a perturbative approach. The simple, yet powerful algorithm used to calculate the effect in a high-temperature expansion in conjunction with zeta function regularization of infrared divergences is explained in detail. The algorithm is shown to be reliable by demonstrating that it reproduces known results for a series of examples. With two-loop contributions properly included, the dynamic modes are seen not to lead to a shift in the condensation temperature, thus revising our earlier finding obtained at one loop., Comment: 17 pages, no figures Updated version includes two-loop contributions

Published
2003

37. Gauge-invariant critical exponents for the Ginzburg-Landau model

Author

Kleinert, H. and Schakel, Adriaan M. J.

Subjects
Condensed Matter
Abstract

The critical behavior of the Ginzburg-Landau model is described in a manifestly gauge-invariant manner. The gauge-invariant correlation-function exponent is computed to first order in the $4-d$ and $1/n$-expansion, and found to agree with the ordinary exponent obtained in the covariant gauge, with the parameter $\alpha=1-d$ in the gauge-fixing term $(\partial_\mu A_\mu)^2 /2 \alpha$., Comment: 4 pages, no figures

Published
2002
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38. Entangled Vortices: Onsager's geometrical picture of superfluid phase transitions

Author

Schakel, Adriaan M. J.

Subjects
Condensed Matter
Abstract

Superfluid phase transitions are discussed from a geometrical perspective as envisaged by Onsager. The approach focuses on vortex loops which close to the critical temperature form a fluctuating vortex tangle. As the transition is approached, vortex lines proliferate and thereby disorder the superfluid state, so that the system reverts to the normal state. It is shown in detail that loop proliferation can be described in exactly the same way as cluster percolation. Picturing vortex loops as worldlines of bosons, with one of the spatial coordinates interpreted as the time coordinate, a quantitative description of vortex loops can be given. Applying a rotation (to superfluids) or a magnetic field (to superconductors), which suppresses the formation of vortex loops and instead can lead to open vortex lines along the field direction, is shown to be equivalent to taking the nonrelativistic limit. The nonrelativistic theory is the one often used to study vortex lattice melting and to describe the resulting entangled vortex liquid., Comment: 24 pages, 14 figures, write-up of lectures presented at the Kevo Winter School, Kevo, Finland, 20-26 April 2002

Published
2002

39. Effective Free Energy of Ginzburg-Landau Model

Author

Schakel, Adriaan M. J.

Subjects
Condensed Matter
Abstract

It is argued that the presence of a nonanalytic term in the effective potential of the Ginzburg-Landau model is immaterial as far as the order of the superconductor-normal phase transition is concerned. To achieve agreement with the renormalization group, the effective potential has to be extended to include derivative terms, which provide the theory with a low momentum scale which can be varied to probe the (possible) fixed point., Comment: 6 pages, contribution to the Festschrift dedicated to Professor Kleinert on the occasion of his 60th birthday

Published
2001
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40. On the Ground State of Electron Gases at Negative Compressibility

Author

Schakel, Adriaan M. J.

Subjects
Condensed Matter
Abstract

Two- and three-dimensional electron gases with a uniform neutralizing background are studied at negative compressibility. Parametrized expressions for the dielectric function are used to access this strong-coupling regime, where the screened Coulomb potential becomes overall attractive for like charges. Closely examining these expressions reveals that the ground state with a periodic modulation of the charge density, albeit exponentially damped, replaces the homogeneous one at positive compressibility. The wavevector characterizing the new ground state depends on the density and is complex, having a positive imaginary part, as does the homogeneous ground state, and real part, as does the genuine charge density wave., Comment: 6 double-column pages, 2 figures. 2nd version is an extension of the 1st one, giving more details

Published
2001
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41. Superconductor-Insulator Quantum Phase Transitions

Author

Schakel, Adriaan M. J.

Subjects
Condensed Matter
Abstract

In these lectures, superconductivity in impure thin films close to the absolute zero of temperature is discussed. The behavior as function of the applied magnetic field and the amount of impurities suggests the presence of a superconductor-insulator transition at zero temperature. The theory of superconductivity in the limit where all the electrons become tightly bound in pairs is used to explain the main characteristics of the transition. In that limit, where the theory becomes equivalent to a phase-only theory, electron pairs exist on either side of the transition. The presentation is pedagogical in nature and includes exercises as a learning aid for those new to the field., Comment: 36 pages, lectures presented at the XL Cracow School of Theoretical Physics, Zakopane, Poland, June 3-11, 2000, to appear in the proceedings as a special issue of Acta Physica Polonica B, see http://th-www.if.uj.edu.pl/acta/

Published
2000

42. Percolation, Bose-Einstein Condensation, and String Proliferation

Author

Schakel, Adriaan M. J.

Subjects
Condensed Matter
Abstract

The close analogy between cluster percolation and string proliferation in the context of critical phenomena is studied. Like clusters in percolation theory, closed strings, which can be either finite-temperature worldlines or topological line defects, are described by a distribution parametrized by only two exponents. On approaching the critical point, the string tension vanishes, and the loops proliferate thereby signalling the onset of Bose-Einstein condensation (in case of worldlines) or the disordering of the ordered state (in case of vortices). The ideal Bose gas with modified energy spectrum is used as a stepping stone to derive general expressions for the critical exponents in terms of the two exponents parameterizing the loop distribution near criticality., Comment: 12 pages, 3x2 figures

Published
2000
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43. Vertical Melting of a Stack of Membranes

Author

Borelli, M. E. S., Kleinert, H., and Schakel, Adriaan M. J.

Subjects
Condensed Matter
Abstract

A stack of tensionless membranes with nonlinear curvature energy and vertical harmonic interaction is studied. At low temperatures, the system forms a lamellar phase. At a critical temperature, the stack disorders vertically in a melting-like transition., Comment: 8 pages, 2 figures

Published
2000
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44. Comment on 'The Transition Temperature of the Dilute Interacting Bose Gas' and on 'Transition Temperature of a Uniform Bose Gas'

Author

Schakel, Adriaan M. J.

Subjects
Condensed Matter
Abstract

It is pointed out that first, contrary to the claim by Baym et al.[Phys. Rev. Lett 83, 1703 (1999)], the shift in the transition temperature of a weakly interacting Bose gas can be calculated perturbatively. And second, that the regime considered by Huang [Phys. Rev. Lett 83, 3770 (1999)] while addressing the same issue does not describe the Bose-Einstein condensed phase., Comment: One page comment

Published
2000

45. Self-Duality in Superconductor-Insulator Quantum Phase Transitions

Author

Schakel, Adriaan M. J.

Subjects
Condensed Matter
Abstract

It is argued that close to a Coulomb interacting quantum critical point, the interaction between two vortices in a disordered superconducting thin film separated by a distance $r$ changes from logarithmic in the mean-field region to $1/r$ in the region dominated by quantum critical fluctuations. This gives support to the charge-vortex duality picture of the observed reflection symmetry in the current-voltage characteristics on both sides of the transition., Comment: 4 pages, no figures, 2nd version: title (slightly) changed and text accordingly

Published
2000
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46. Gestational oxidative stress protects against adult obesity and insulin resistance

Author

Lidiya G. Dimova, Simone Battista, Torsten Plösch, Rosalie A. Kampen, Fan Liu, Rikst Nynke Verkaik-Schakel, Domenico Pratico, Henkjan J. Verkade, and Uwe J.F. Tietge

Subjects
Medicine (General), R5-920, Biology (General), QH301-705.5
Abstract

Pregnancy complications such as preeclampsia cause increased fetal oxidative stress and fetal growth restriction, and associate with a higher incidence of adult metabolic syndrome. However, the pathophysiological contribution of oxidative stress per se is experimentally difficult to discern and has not been investigated. This study determined, if increased intrauterine oxidative stress (IUOx) affects adiposity, glucose and cholesterol metabolism in adult Ldlr−/−xSod2+/+ offspring from crossing male Ldlr−/−xSod2+/+ mice with Ldlr−/−xSod2 +/- dams (IUOx) or Ldlr−/−xSod2 +/- males with Ldlr−/−xSod2+/+ dams (control). At 12 weeks of age mice received Western diet for an additional 12 weeks. Adult male IUOx offspring displayed lower body weight and reduced adiposity associated with improved glucose tolerance compared to controls. Reduced weight gain in IUOx was conceivably due to increased energy dissipation in white adipose tissue conveyed by higher expression of Ucp1 and an accompanying decrease in DNA methylation in the Ucp1 enhancer region. Female offspring did not show comparable phenotypes. These results demonstrate that fetal oxidative stress protects against the obesogenic effects of Western diet in adulthood by programming energy dissipation in white adipose tissue at the level of Ucp1. Keywords: Fetal oxidative stress, Mitohormesis, Metabolic programming, Adiposity, Epigenetics, Methylation

Published
2020
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47. Bogoliubov's Theory: A Paradigm of Quantum Phase Transitions

Author

Schakel, Adriaan M. J.

Subjects
Condensed Matter
Abstract

This short essay discusses the application of Bogoliubov's theory of superfluidity in the context of quantum phase transitions., Comment: 13 pages, contribution to special issue of Journal of Physical Studies commemorating Bogoliubov's 90s birthday

Published
1999

48. Quantum Statistical Mechanics of Nonrelativistic Membranes: Crumpling Transition at Finite Temperature

Author

Borelli, M. E. S., Kleinert, H., and Schakel, Adriaan M. J.

Subjects
Condensed Matter
Abstract

The effect of quantum fluctuations on a nearly flat, nonrelativistic two-dimensional membrane with extrinsic curvature stiffness and tension is investigated. The renormalization group analysis is carried out in first-order perturbative theory. In contrast to thermal fluctuations, which soften the membrane at large scales and turn it into a crumpled surface, quantum fluctuations are found to {\em stiffen} the membrane, so that it exhibits a Hausdorff dimension equal to two. The large-scale behavior of the membrane is further studied at finite temperature, where a nontrivial fixed point is found, signaling a crumpling transition., Comment: RevTex, 9 pages, 1 figure

Published
1999
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49. String Picture of Bose-Einstein Condensation

Author

Bund, S. and Schakel, Adriaan M. J.

Subjects
Condensed Matter
Abstract

A nonrelativistic Bose gas is represented as a grand-canonical ensemble of fluctuating closed spacetime strings of arbitrary shape and length. The loops are characterized by their string tension and the number of times they wind around the imaginary time axis. At the temperature where Bose-Einstein condensation sets in, the string tension, being determined by the chemical potential, vanishes, the system becomes critical, and the strings proliferate. A comparison with Feynman's description in terms of rings of cyclicly permuted bosons shows that the winding number of a loop corresponds to the number of particles contained in a ring., Comment: 13 pages, 6 figures; references added

Published
1999
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50. Time-Dependent Ginzburg-Landau Theory and Duality

Author

Schakel, Adriaan M. J.

Subjects
Condensed Matter
Abstract

In the first part of this review paper, the time-dependent Ginzburg-Landau theory is derived starting from the microscopic BCS model with the help of a derivative expansion. Special attention is paid to two space dimensions, where the entire crossover from the weak-coupling BCS limit to the strong-coupling BEC limit of tightly bound fermion pairs is accessible analytically. The second part deals with the dual approach to the time-independent Ginzburg-Landau theory in three space dimensions. In this approach, the magnetic vortices of a superconductor play the central role, and the superconductor-to-normal phase transition is understood as a proliferation of these vortices., Comment: 16 pages, 1 figure. Lectures presented at the NATO Winter School and European Science Foundation (ESF) Workshop Topological Defects and the Non-Equilibrium Dynamics of Symmetry Breaking Phase Transitions, Les Houches, February 16-26, 1999, in Topological Defects in Cosmology and Condensed Matter Physics, edited by Yu. Bunkov and H. Godfrin (Kluwer, Dordrecht, 2000)

Published
1999

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