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Author Papavassiliou, J.
Title Emergence of mass in the gauge sector of QCD Type Journal Article
Year 2022 Publication Chinese Physics C Abbreviated Journal Chin. Phys. C
Volume 46 Issue 11 Pages 112001 - 23pp
Keywords non perturbative QCD; Schwinger-Dyson equations; Schwinger functions
Abstract It is currently widely accepted that gluons, while massless at the level of the fundamental QCD Lagrangian, acquire an effective mass through the non-Abelian implementation of the classic Schwinger mechanism. The key dynamical ingredient that triggers the onset of this mechanism is the formation of composite massless poles inside the fundamental vertices of the theory. These poles enter the evolution equation of the gluon propagator and nontrivially affect the way the Slavnov-Taylor identities of the vertices are resolved, inducing a smoking-gun displacement in the corresponding Ward identities. In this article, we present a comprehensive review of the pivotal concepts associated with this dynamical scenario, emphasizing the synergy between functional methods and lattice simulations and highlighting recent advances that corroborate the action of the Schwinger mechanism in QCD.
Address (down) [Papavassiliou, J.] Univ Valencia, Dept Theoret Phys, E-46100 Valencia, Spain, Email: joannis.papavassiliou@uv.es
Corporate Author Thesis
Publisher IOP Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1674-1137 ISBN Medium
Area Expedition Conference
Notes WOS:000873336100001 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 5398
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Author Panes, B.; Eckner, C.; Hendriks, L.; Caron, S.; Dijkstra, K.; Johannesson, G.; Ruiz de Austri, R.; Zaharijas, G.
Title Identification of point sources in gamma rays using U-shaped convolutional neural networks and a data challenge Type Journal Article
Year 2021 Publication Astronomy & Astrophysics Abbreviated Journal Astron. Astrophys.
Volume 656 Issue Pages A62 - 18pp
Keywords catalogs; gamma rays: general; astroparticle physics; methods: numerical; methods: data analysis; techniques: image processing
Abstract Context. At GeV energies, the sky is dominated by the interstellar emission from the Galaxy. With limited statistics and spatial resolution, accurately separating point sources is therefore challenging. Aims. Here we present the first application of deep learning based algorithms to automatically detect and classify point sources from gamma-ray data. For concreteness we refer to this approach as AutoSourceID. Methods. To detect point sources, we utilized U-shaped convolutional networks for image segmentation and k-means for source clustering and localization. We also explored the Centroid-Net algorithm, which is designed to find and count objects. Using two algorithms allows for a cross check of the results, while a combination of their results can be used to improve performance. The training data are based on 9.5 years of exposure from The Fermi Large Area Telescope (Fermi-LAT) and we used source properties of active galactic nuclei (AGNs) and pulsars (PSRs) from the fourth Fermi-LAT source catalog in addition to several models of background interstellar emission. The results of the localization algorithm are fed into a classification neural network that is trained to separate the three general source classes (AGNs, PSRs, and FAKE sources). Results. We compared our localization algorithms qualitatively with traditional methods and find them to have similar detection thresholds. We also demonstrate the robustness of our source localization algorithms to modifications in the interstellar emission models, which presents a clear advantage over traditional methods. The classification network is able to discriminate between the three classes with typical accuracy of similar to 70%, as long as balanced data sets are used in classification training. We published online our training data sets and analysis scripts and invite the community to join the data challenge aimed to improve the localization and classification of gamma-ray point sources.
Address (down) [Panes, Boris] Pontificia Univ Catolica Chile, Ave Vicuna Mackenna 4860, Macul, Region Metropol, Chile, Email: bapanes@gmail.com
Corporate Author Thesis
Publisher Edp Sciences S A Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0004-6361 ISBN Medium
Area Expedition Conference
Notes WOS:000725877600001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5053
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Author Pajtler, M.V. et al; Gadea, A.
Title Excited states of Y-90,Y-92,Y-94 populated in Zr-90+Pb-208 multinucleon transfer reaction Type Journal Article
Year 2021 Publication Physica Scripta Abbreviated Journal Phys. Scr.
Volume 96 Issue 3 Pages 035305 - 7pp
Keywords multinucleon transfer reactions; gamma spectroscopy; magnetic spectrometers; gamma-ray spectrometers
Abstract Multinucleon transfer reactions in Zr-90+Pb-208 have been studied via fragment-gamma coincidences, employing the PRISMA magnetic spectrometer coupled to the CLARA gamma-array. An analysis on Y isotopes has been carried out incorporating spectroscopic as well as reaction mechanism aspects. New gamma transitions have been observed in Y-94, confirming the findings of recent studies where nuclei were produced via fission of uranium, and a comparison with near-by Y-90,Y-92 isotopes populated in the same reaction has been discussed. Experimental cross sections have been extracted and compared with the GRAZING calculations, showing a fair agreement along the neutron pick-up side. The results confirm how multinucleon transfer reactions are a suitable mechanism for the study of neutron-rich nuclei.
Address (down) [Pajtler, M. Varga] Univ Osijek, Dept Phys, Osijek, Croatia, Email: Suzana.Szilner@irb.hr;
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-8949 ISBN Medium
Area Expedition Conference
Notes WOS:000611517400001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4694
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Author Otten, S.; Rolbiecki, K.; Caron, S.; Kim, J.S.; Ruiz de Austri, R.; Tattersall, J.
Title DeepXS: fast approximation of MSSM electroweak cross sections at NLO Type Journal Article
Year 2020 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 80 Issue 1 Pages 12 - 9pp
Keywords
Abstract We present a deep learning solution to the prediction of particle production cross sections over a complicated, high-dimensional parameter space. We demonstrate the applicability by providing state-of-the-art predictions for the production of charginos and neutralinos at the Large Hadron Collider (LHC) at the next-to-leading order in the phenomenological MSSM-19 and explicitly demonstrate the performance for pp ->(chi) over tilde (+)(1)(chi) over tilde (-)(1), (chi) over tilde (0)(2)(chi) over tilde (0)(2) and (chi) over tilde (0)(2)(chi) over tilde (+/-)(1) as a proof of concept which will be extended to all SUSY electroweak pairs. We obtain errors that are lower than the uncertainty from scale and parton distribution functions with mean absolute percentage errors of well below 0.5% allowing a safe inference at the next-to-leading order with inference times that improve the Monte Carlo integration procedures that have been available so far by a factor of O(10(7)) from O(min) to O(mu s) per evaluation.
Address (down) [Otten, Sydney; Caron, Sascha] Radboud Univ Nijmegen, IMAPP, Nijmegen, Netherlands, Email: Sydney.Otten@ru.nl
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1434-6044 ISBN Medium
Area Expedition Conference
Notes WOS:000513271500001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4279
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Author Otten, S.; Caron, S.; de Swart, W.; van Beekveld, M.; Hendriks, L.; van Leeuwen, C.; Podareanu, D.; Ruiz de Austri, R.; Verheyen, R.
Title Event generation and statistical sampling for physics with deep generative models and a density information buffer Type Journal Article
Year 2021 Publication Nature Communications Abbreviated Journal Nat. Commun.
Volume 12 Issue 1 Pages 2985 - 16pp
Keywords
Abstract Simulating nature and in particular processes in particle physics require expensive computations and sometimes would take much longer than scientists can afford. Here, we explore ways to a solution for this problem by investigating recent advances in generative modeling and present a study for the generation of events from a physical process with deep generative models. The simulation of physical processes requires not only the production of physical events, but to also ensure that these events occur with the correct frequencies. We investigate the feasibility of learning the event generation and the frequency of occurrence with several generative machine learning models to produce events like Monte Carlo generators. We study three processes: a simple two-body decay, the processes e(+)e(-)-> Z -> l(+)l(-) and pp -> tt<mml:mo><overbar></mml:mover> including the decay of the top quarks and a simulation of the detector response. By buffering density information of encoded Monte Carlo events given the encoder of a Variational Autoencoder we are able to construct a prior for the sampling of new events from the decoder that yields distributions that are in very good agreement with real Monte Carlo events and are generated several orders of magnitude faster. Applications of this work include generic density estimation and sampling, targeted event generation via a principal component analysis of encoded ground truth data, anomaly detection and more efficient importance sampling, e.g., for the phase space integration of matrix elements in quantum field theories. Here, the authors report buffered-density variational autoencoders for the generation of physical events. This method is computationally less expensive over other traditional methods and beyond accelerating the data generation process, it can help to steer the generation and to detect anomalies.
Address (down) [Otten, Sydney; Caron, Sascha; de Swart, Wieske; van Beekveld, Melissa; Hendriks, Luc; Verheyen, Rob] Radboud Univ Nijmegen, Inst Math Astro & Particle Phys IMAPP, Nijmegen, Netherlands, Email: Sydney.Otten@ru.nl
Corporate Author Thesis
Publisher Nature Research Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2041-1723 ISBN Medium
Area Expedition Conference
Notes WOS:000658761600003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4862
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Author Otal, A.; Celada, F.; Chimeno, J.; Vijande, J.; Pellejero, S.; Perez-Calatayud, M.J.; Villafranca, E.; Fuentemilla, N.; Blazquez, F.; Rodriguez, S.; Perez-Calatayud, J.
Title Review on Treatment Planning Systems for Cervix Brachytherapy (Interventional Radiotherapy): Some Desirable and Convenient Practical Aspects to Be Implemented from Radiation Oncologist and Medical Physics Perspectives Type Journal Article
Year 2022 Publication Cancers Abbreviated Journal Cancers
Volume 14 Issue 14 Pages 3467 - 15pp
Keywords cervix; treatment planning systems; interstitial applicators; magnetic resonance
Abstract Simple Summary There are no brachytherapy treatment planning systems (TPS) exclusively for the treatment of cervical tumours, so general-purpose TPSs are used. However, these treatments have some particular features concerning the treatment of other pathologies, especially in the case of exclusive use of MRI as an imaging modality and the presence of gynaecological applicators in combination with an interstitial part. That is why it is essential to review the latest versions of commercial TPSs to find the potential features to improve with the help of a group of experimented medical physicists and radiation oncologists. Furthermore, after reviewing the recent literature for advances applicable to cervical brachytherapy and through his own clinical experience, possible improvements are proposed to software providers for the development of new tools. Intracavitary brachytherapy (BT, Interventional Radiotherapy, IRT), plays an essential role in the curative intent of locally advanced cervical cancer, for which the conventional approach involves external beam radiotherapy with concurrent chemotherapy followed by BT. This work aims to review the different methodologies used by commercially available treatment planning systems (TPSs) in exclusive magnetic resonance imaging-based (MRI) cervix BT with interstitial component treatments. Practical aspects and improvements to be implemented into the TPSs are discussed. This review is based on the clinical expertise of a group of radiation oncologists and medical physicists and on interactive demos provided by the software manufacturers. The TPS versions considered include all the new tools currently in development for future commercial releases. The specialists from the supplier companies were asked to propose solutions to some of the challenges often encountered in a clinical environment through a questionnaire. The results include not only such answers but also comments by the authors that, in their opinion, could help solve the challenges covered in these questions. This study summarizes the possibilities offered nowadays by commercial TPSs, highlighting the absence of some useful tools that would notably improve the planning of MR-based interstitial component cervix brachytherapy.
Address (down) [Otal, Antonio] Hosp Arnau Vilanova, Med Phys Dept, Lleida 25198, Spain, Email: aotalpalacin@gmail.com;
Corporate Author Thesis
Publisher Mdpi Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes WOS:000832057600001 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 5304
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Author Oset, E.; Roca, L.
Title Exotic molecular meson states of B(*) K(*) nature Type Journal Article
Year 2022 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 82 Issue 10 Pages 882 - 9pp
Keywords
Abstract We evaluate theoretically the interaction of the open bottom and strange systems (B) over bar (K) over bar, (B) over bar * (K) over bar, (B) over bar (K) over bar * and (B) over bar* (K) over bar* to look for possible bound states which could correspond to exotic non-quark-antiquark mesons since they would contain at least one b and one s quarks. The s-wave scattering matrix is evaluated implementing unitarity by means of the Bethe-Salpeter equation, with the potential kernels obtained from contact and vector meson exchange mechanisms. The vertices needed are supplied from Lagrangians derived from suitable extensions of the hidden gauge symmetry approach to the bottom sector. We find poles below the respective thresholds for isospin 0 interaction and evaluate the widths of the different obtained states by including the main sources of imaginary part, which are the B *-> B gamma decay in the (B) over bar * (K) over bar channels, the K *-> K pi in the channels involving a K *, plus the box diagrams with (B) over bar (K) over bar and (B) over bar * (K) over bar intermediate states for the (B) over bar * (K) over bar * channels.
Address (down) [Oset, E.] Univ Valencia, Ctr Mixto, CSIC, Inst Invest Paterna,Dept Fis Teor, Aptdo 22085, Valencia 46071, Spain, Email: oset@ific.uv.es;
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1434-6044 ISBN Medium
Area Expedition Conference
Notes WOS:000864656100003 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 5369
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Author Ortiz Arciniega, J.L.; Carrio, F.; Valero, A.
Title FPGA implementation of a deep learning algorithm for real-time signal reconstruction in particle detectors under high pile-up conditions Type Journal Article
Year 2019 Publication Journal of Instrumentation Abbreviated Journal J. Instrum.
Volume 14 Issue Pages P09002 - 13pp
Keywords Data processing methods; Pattern recognition; cluster finding; calibration and fitting methods; Simulation methods and programs
Abstract The analog signals generated in the read-out electronics of particle detectors are shaped prior to the digitization in order to improve the signal to noise ratio (SNR). The real amplitude of the analog signal is then obtained using digital filters, which provides information about the energy deposited in the detector. The classical digital filters have a good performance in ideal situations with Gaussian electronic noise and no pulse shape distortion. However, high-energy particle colliders, such as the Large Hadron Collider (LHC) at CERN, can produce multiple simultaneous events, which produce signal pileup. The performance of classical digital filters deteriorates in these conditions since the signal pulse shape gets distorted. In addition, this type of experiments produces a high rate of collisions, which requires high throughput data acquisitions systems. In order to cope with these harsh requirements, new read-out electronics systems are based on high-performance FPGAs, which permit the utilization of more advanced real-time signal reconstruction algorithms. In this paper, a deep learning method is proposed for real-time signal reconstruction in high pileup particle detectors. The performance of the new method has been studied using simulated data and the results are compared with a classical FIR filter method. In particular, the signals and FIR filter used in the ATLAS Tile Calorimeter are used as benchmark. The implementation, resources usage and performance of the proposed Neural Network algorithm in FPGA are also presented.
Address (down) [Ortiz Arciniega, J. L.] Univ Valencia, Avinguda Univ S-N, Burjassot, Spain, Email: orarjo@alumni.uv.es
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1748-0221 ISBN Medium
Area Expedition Conference
Notes WOS:000486990000002 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 4150
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Author Orrigo, S.E.A.; Tain, J.L.; Mont-Geli, N.; Tarifeño-Saldivia, A.; Fraile, L.M.; Grieger, M.; Agramunt, J.; Algora, A.; Bemmerer, D.; Calvino, F.; Cortes, G.; De Blas, A.; Dillmann, I.; Dominguez Bugarin, A.; Garcia, R.; Nacher, E.; Tolosa-Delgado, A.
Title Long-term evolution of the neutron rate at the Canfranc Underground Laboratory Type Journal Article
Year 2022 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 82 Issue 9 Pages 814 - 11pp
Keywords
Abstract We report results on the long-term variation of the neutron counting rate at the Canfranc Underground Laboratory, of importance for several low-background experiments installed there, including rare-event searches. The measurement campaign was performed employing the High Efficiency Neutron Spectrometry Array (HENSA) mounted in Hall A and lasted 412 live days. The present study is the first long-term measurement of the neutron rate with sensitivity over a wide range of neutron energies (from thermal up to 0.1 GeV and beyond) performed in any underground laboratory so far. Data on the environmental variables inside the experimental hall (radon concentration, air temperature, air pressure and humidity) were also acquired during all the measurement campaign. We have investigated for the first time the evolution of the neutron rate for different energies of the neutrons and its correlation with the ambient variables.
Address (down) [Orrigo, S. E. A.; Tain, J. L.; Agramunt, J.; Algora, A.; Nacher, E.; Tolosa-Delgado, A.] Univ Valencia, Inst Fis Corpuscular, CSIC, Valencia 46071, Spain, Email: Sonja.Orrigo@ific.uv.es
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1434-6044 ISBN Medium
Area Expedition Conference
Notes WOS:000853333800003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5358
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Author Orrigo, S.E A. et al; Rubio, B.; Gelletly, W.; Aguilera, P.; Algora, A.; Morales, A.I.; Agramunt, J.; Guadilla, V.; Montaner-Piza, A.
Title beta decay of the very neutron-deficient Ge-60 and Ge-62 nuclei Type Journal Article
Year 2021 Publication Physical Review C Abbreviated Journal Phys. Rev. C
Volume 103 Issue 1 Pages 014324 - 12pp
Keywords
Abstract We report here the results of a study of the beta decay of the proton-rich Ge isotopes, Ge-60 and Ge-62, produced in an experiment at the RIKEN Nishina Center. We have improved our knowledge of the half-lives of Ge-62 [73.5(1) ms] and Ge-60 [25.0(3) ms] and its daughter nucleus, Ga-60 [69.4(2) ms]. We measured individual beta-delayed proton and gamma emissions and their related branching ratios. Decay schemes and absolute Fermi and Gamow-Teller transition strengths have been determined. The mass excesses of the nuclei under study have been deduced. A total beta-delayed proton-emission branching ratio of 67(3)% has been obtained for Ge-60. New information has been obtained on the energy levels populated in Ga-60 and on the 1/2(-) excited state in the beta p daughter Zn-59. We extracted a ground state-to-ground state feeding of 85.3(3)% for the decay of Ge-62. Eight new y lines have been added to the deexcitation of levels populated in the Ga-62 daughter.
Address (down) [Orrigo, S. E. A.; Rubio, B.; Gelletly, W.; Aguilera, P.; Algora, A.; Morales, A., I; Agramunt, J.; Guadilla, V; Montaner-Piza, A.] Univ Valencia, Inst Fis Corpuscular, CSIC, E-46071 Valencia, Spain, Email: sonja.orrigo@ific.uv.es
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2469-9985 ISBN Medium
Area Expedition Conference
Notes WOS:000613141500002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4716
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