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Author Borsato, M. et al; Zurita, J.; Henry, L.; Jashal, B.K.; Oyanguren, A.
Title Unleashing the full power of LHCb to probe stealth new physics Type Journal Article
Year 2022 Publication (down) Reports on Progress in Physics Abbreviated Journal Rep. Prog. Phys.
Volume 85 Issue 2 Pages 024201 - 45pp
Keywords LHCb; stealth physics; BSM physics; hidden sectors; long-lived particles; dark matter
Abstract In this paper, we describe the potential of the LHCb experiment to detect stealth physics. This refers to dynamics beyond the standard model that would elude searches that focus on energetic objects or precision measurements of known processes. Stealth signatures include long-lived particles and light resonances that are produced very rarely or together with overwhelming backgrounds. We will discuss why LHCb is equipped to discover this kind of physics at the Large Hadron Collider and provide examples of well-motivated theoretical models that can be probed with great detail at the experiment.
Address [Borsato, M.] Heidelberg Univ, Phys Inst, Heidelberg, Germany, Email: xabier.cid.vidal@cern.ch
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 0034-4885 ISBN Medium
Area Expedition Conference
Notes WOS:000762056700001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5151
Permanent link to this record
 
 
Author AbdusSalam, S.S. et al; Eberhardt, O.
Title Simple and statistically sound recommendations for analysing physical theories Type Journal Article
Year 2022 Publication (down) Reports on Progress in Physics Abbreviated Journal Rep. Prog. Phys.
Volume 85 Issue 5 Pages 052201 - 11pp
Keywords particle physics; statistics; methodology
Abstract Physical theories that depend on many parameters or are tested against data from many different experiments pose unique challenges to statistical inference. Many models in particle physics, astrophysics and cosmology fall into one or both of these categories. These issues are often sidestepped with statistically unsound ad hoc methods, involving intersection of parameter intervals estimated by multiple experiments, and random or grid sampling of model parameters. Whilst these methods are easy to apply, they exhibit pathologies even in low-dimensional parameter spaces, and quickly become problematic to use and interpret in higher dimensions. In this article we give clear guidance for going beyond these procedures, suggesting where possible simple methods for performing statistically sound inference, and recommendations of readily-available software tools and standards that can assist in doing so. Our aim is to provide any physicists lacking comprehensive statistical training with recommendations for reaching correct scientific conclusions, with only a modest increase in analysis burden. Our examples can be reproduced with the code publicly available at Zenodo.
Address [AbdusSalam, Shehu S.; Fowlie, Andrew] Shahid Beheshti Univ, Dept Phys, Tehran, Iran, Email: andrew.j.fowlie@njnu.edu.cn
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 0034-4885 ISBN Medium
Area Expedition Conference
Notes WOS:000791574900001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5221
Permanent link to this record
 
 
Author Perez-Calatayud, J.; Ballester, F.; Tedgren, C.; DeWerd, L.A.; Papagiannis, P.; Rivard, M.J.; Siebert, F.A.; Vijande, J.
Title GEC-ESTRO ACROP recommendations on calibration and traceability of HE HDR-PDR photon-emitting brachytherapy sources at the hospital level Type Journal Article
Year 2022 Publication (down) Radiotherapy and Oncology Abbreviated Journal Radiother. Oncol.
Volume 176 Issue Pages 108-117
Keywords Brachytherapy; High energy; Calibration; Dosimetry; HDR-PDR
Abstract The vast majority of radiotherapy departments in Europe using brachytherapy (BT) perform temporary implants of high-or pulsed-dose rate (HDR-PDR) sources with photon energies higher than 50 keV. Such techniques are successfully applied to diverse pathologies and clinical scenarios. These recommen-dations are the result of Working Package 21 (WP-21) initiated within the BRAchytherapy PHYsics Quality Assurance System (BRAPHYQS) GEC-ESTRO working group with a focus on HDR-PDR source cal-ibration. They provide guidance on the calibration of such sources, including practical aspects and issues not specifically accounted for in well-accepted societal recommendations, complementing the BRAPHYQS WP-18 Report dedicated to low energy BT photon emitting sources (seeds). The aim of this report is to provide a European-wide standard in HDR-PDR BT source calibration at the hospital level to maintain high quality patient treatments.
Address [Perez-Calatayud, Jose] La Fe Hosp, Radiotherapy Dept, Valencia, Spain, Email: javier.vijande@uv.es
Corporate Author Thesis
Publisher Elsevier Ireland Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0167-8140 ISBN Medium
Area Expedition Conference
Notes WOS:000880438000006 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5466
Permanent link to this record
 
 
Author Viegas, R.; Roser, J.; Barrientos, L.; Borja-Lloret, M.; Casaña, J.V.; Lopez, J.G.; Jimenez-Ramos, M.C.; Hueso-Gonzalez, F.; Ros, A.; Llosa, G.
Title Characterization of a Compton camera based on the TOFPET2 ASIC Type Journal Article
Year 2023 Publication (down) Radiation Physics and Chemistry Abbreviated Journal Radiat. Phys. Chem.
Volume 202 Issue Pages 110507 - 11pp
Keywords Compton camera; Hadron therapy; LaBr3; PETsys TOFPET2; Silicon photomultipliers
Abstract The use of Compton cameras for medical imaging and its interest as a hadron therapy treatment monitoring has increased in the last decade with the development of silicon photomultipliers. MACACOp is a Compton camera prototype designed and assembled at the IRIS group of IFIC-Valencia. This Compton camera is based on monolithic Lanthanum (III) Bromide crystals and silicon photomultipliers, and employs the novel TOFPET2 ASIC as readout electronics. This system emerged as an alternative to MACACO II prototype, with the aim of improving its limited time resolution. To test the performance of the ASIC in a Compton camera setup, the prototype was characterized, both in laboratory and in-beam. A time resolution of 1.5 ns was obtained after time corrections, which improves greatly the performance of the MACACO II. Moreover, the results obtained at high photon energies demonstrate the ability of the system to obtain 1 mm displacements of the reconstructed spots. The results reinforce the potential of the system as a monitoring device for hadron therapy.
Address [Viegas, R.; Roser, J.; Barrientos, L.; Borja-Lloret, M.; Casana, J., V; Hueso-Gonzalez, F.; Ros, A.; Llosa, G.] CSIC UV, Inst Fis Corpuscular IFIC, Valencia, Spain, Email: Rita.Viegas@ific.uv.es
Corporate Author Thesis
Publisher Pergamon-Elsevier Science Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0969-806x ISBN Medium
Area Expedition Conference
Notes WOS:000870840600006 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 5392
Permanent link to this record
 
 
Author Barrientos, L.; Borja-Lloret, M.; Casana, J.V.; Hueso-Gonzalez, F.; Ros, A.; Roser, J.; Senra, C.; Solaz, C.; Viegas, R.; Llosa, G.
Title System characterization and performance studies with MACACO III Compton camera Type Journal Article
Year 2023 Publication (down) Radiation Physics and Chemistry Abbreviated Journal Radiat. Phys. Chem.
Volume 208 Issue Pages 110922 - 13pp
Keywords Compton camera; Scintillator crystals; Silicon photomultipliers
Abstract The IRIS group of IFIC-Valencia has developed a Compton camera prototype. The system detectors are made of Lanthanum (III) bromide scintillator crystals coupled to silicon photomultipliers. Two models of silicon photomultipliers arrays with different micro pixel pitch (25 and 50 μm) have been chosen as possible candidates to improve the response of the new system. Characterization studies with a 22Na point-like source have indicated that the 25 μm photodetector provided better performance in terms of energy resolution (5.2% FWHM at 511 keV) and angular resolution (6.9 degrees FWHM at 1275 keV), and more stability with temperature variations. In addition, MACACO III imaging capabilities have been assessed using a structure composed of thirty-seven 22Na point-like sources. Furthermore, in order to evaluate possible ways of improving the system performance, several studies have been carried out by means of simulations both in realistic and performance improved conditions. In this work, the system performance is evaluated for its future application in different areas.
Address [Barrientos, L.; Borja-Lloret, M.; Casana, J. V.; Hueso-Gonzalez, F.; Ros, A.; Roser, J.; Senra, C.; Solaz, C.; Viegas, R.; Llosa, G.] CSIC UV, Inst Fis Corpuscular IF, Valencia, Spain, Email: Luis.Barrientos@ific.uv.es;
Corporate Author Thesis
Publisher Pergamon-Elsevier Science Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0969-806x ISBN Medium
Area Expedition Conference
Notes WOS:000962800400001 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 5511
Permanent link to this record
 
 
Author Oliver, S.; Vijande, J.; Tejedor-Aguilar, N.; Miro, R.; Rovira-Escutia, J.J.; Ballester, F.; Juste, B.; Carmona, V.; Felici, G.; Verdu, G.; Sanchis, E.; Conde, A.; Perez-Calatayud, J.
Title Monte Carlo flattening filter design to high energy intraoperative electron beam homogenization Type Journal Article
Year 2023 Publication (down) Radiation Physics and Chemistry Abbreviated Journal Radiat. Phys. Chem.
Volume 212 Issue Pages 111102 - 6pp
Keywords Intraoperative radiotherapy; Electron portable LinAc; Flattening filter; Dosimetry; Monte Carlo
Abstract Intraoperative radiotherapy using mobile linear accelerators is used for a wide variety of malignancies. However, when large fields are used in combination with high energies, a deterioration of the flatness dose profile is measured with respect to smaller fields and lower energies. Indeed, for the LIAC HWL of Sordina, this deterioration is observed for the 12 MeV beam combined with 10 cm (or larger) diameter applicator. Aimed to solve this problem, a flattening filter has been designed and validated evaluating the feasibility of its usage at the upper part of the applicator. The design of the filter was based on Monte Carlo simulations because of its accuracy in modeling components of clinical devices, among other purposes. The LIAC 10 cm diameter applicator was modeled and simulated independently by two different research groups using two different MC codes, reproducing the heterogeneity of the 12 MeV energy beam. Then, an iterative process of filter design was carried out. Finally, the MC designed conical filter with the optimal size and height to obtain the desired flattened beam was built in-house using a 3D printer. During the experimental validation of the applicator-filter, percentage depth dose, beam profiles, absolute and peripheral dose measurements were performed to demonstrate the effectiveness of the filter addition in the applicator. These measurements conclude that the beam has been flattened, from 5.9% with the standard configuration to 1.6% for the configuration with the filter, without significant increase of the peripheral dose. Consequently, the new filter-applicator LIAC configuration can be used also in a conventional surgery room. A reduction of 16% of the output dose and a reduction of 1.1 mm in the D50 of the percentage depth dose was measured with respect to the original configuration. This work is a proof-of-concept that demonstrates that it is possible to add a filter able to flatten the beam delivered by the Sordina LIAC HWL. Future studies will focus on more refined technical solutions fully compatible with the integrity of the applicator, including its sterilization, to be safely introduced in the clinical practice.
Address [Oliver, S.; Miro, R.; Juste, B.; Verdu, G.] Univ Polite cn Vale ncia, Inst Segur Ind Radiofis & Medioambiental ISIRYM, Cami Vera S-N, Valencia 46022, Spain, Email: gverdu@iqn.upv.es
Corporate Author Thesis
Publisher Pergamon-Elsevier Science Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0969-806x ISBN Medium
Area Expedition Conference
Notes WOS:001026194900001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5578
Permanent link to this record
 
 
Author n_TOF Collaboration (Alcayne, V. et al); Balibrea-Correa, J.; Domingo-Pardo, C.; Lerendegui-Marco, J.; Babiano-Suarez, V.; Ladarescu, I.
Title A Segmented Total Energy Detector (sTED) optimized for (n,γ) cross-section measurements at n_TOF EAR2 Type Journal Article
Year 2024 Publication (down) Radiation Physics and Chemistry Abbreviated Journal Radiat. Phys. Chem.
Volume 217 Issue Pages 11pp
Keywords Neutron capture; PHWT; Scintillation detectors; Monte Carlo simulation
Abstract The neutron time-of-flight facility nTOF at CERN is a spallation source dedicated to measurements of neutroninduced reaction cross-sections of interest in nuclear technologies, astrophysics, and other applications. Since 2014, Experimental ARea 2 (EAR2) is operational and delivers a neutron fluence of similar to 4 center dot 10(7) neutrons per nominal proton pulse, which is similar to 50 times higher than the one of Experimental ARea 1 (EAR1) of similar to 8 center dot 10(5) neutrons per pulse. The high neutron flux at EAR2 results in high counting rates in the detectors that challenged the previously existing capture detection systems. For this reason, a Segmented Total Energy Detector (sTED) has been developed to overcome the limitations in the detector's response, by reducing the active volume per module and by using a photo-multiplier (PMT) optimized for high counting rates. This paper presents the main characteristics of the sTED, including energy and time resolution, response to gamma-rays, and provides as well details of the use of the Pulse Height Weighting Technique (PHWT) with this detector. The sTED has been validated to perform neutron-capture cross-section measurements in EAR2 in the neutron energy range from thermal up to at least 400 keV. The detector has already been successfully used in several measurements at nTOF EAR2.
Address [Alcayne, V.; Cano-Ott, D.; Garcia, J.; Gonzalez-Romero, E.; Martinez, T.; de Rada, A. Perez; Plaza, J.; Sanchez-Caballero, A.; Mendoza, E.] Ctr Invest Energet Medioambient & Tecnol CIEMAT, Madrid, Spain, Email: victor.alcayne@ciemat.es
Corporate Author Thesis
Publisher Pergamon-Elsevier Science Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0969-806x ISBN Medium
Area Expedition Conference
Notes WOS:001185584800001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5999
Permanent link to this record
 
 
Author Jay, G.; Arnault, P.; Debbasch, F.
Title Dirac quantum walks with conserved angular momentum Type Journal Article
Year 2021 Publication (down) Quantum Studies-Mathematics and Foundations Abbreviated Journal Quantum Stud. Math. Found.
Volume 8 Issue Pages 419-430
Keywords Quantum walks; Quantum simulation; Lattice field theory
Abstract A quantum walk (QW) simulating the flat (1+2)D Dirac equation on a spatial polar grid is constructed. Because fermions are represented by spinors, which do not constitute a representation of the rotation group SO(3), but rather of its double cover SU(2), the QW can only be defined globally on an extended spacetime where the polar angle extends from 0 to 4 pi. The coupling of the QW with arbitrary electromagnetic fields is also presented. Finally, the cylindrical relativistic Landau levels of the Dirac equation are computed explicitly and simulated by the QW.
Address [Jay, Gareth] Univ Western Australia, Phys Dept, Perth, WA 6009, Australia, Email: gareth.jay@uwa.edu.au;
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 2196-5609 ISBN Medium
Area Expedition Conference
Notes WOS:000697709700001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4975
Permanent link to this record
 
 
Author Nzongani, U.; Zylberman, J.; Doncecchi, C.E.; Perez, A.; Debbasch, F.; Arnault, P.
Title Quantum circuits for discrete-time quantum walks with position-dependent coin operator Type Journal Article
Year 2023 Publication (down) Quantum Information Processing Abbreviated Journal Quantum Inf. Process.
Volume 22 Issue 7 Pages 270 - 46pp
Keywords Quantum walks; Quantum circuits; Quantum simulation
Abstract The aim of this paper is to build quantum circuits that implement discrete-time quantum walks having an arbitrary position-dependent coin operator. The position of the walker is encoded in base 2: with n wires, each corresponding to one qubit, we encode 2(n) position states. The data necessary to define an arbitrary position-dependent coin operator is therefore exponential in n. Hence, the exponentiality will necessarily appear somewhere in our circuits. We first propose a circuit implementing the position-dependent coin operator, that is naive, in the sense that it has exponential depth and implements sequentially all appropriate position-dependent coin operators. We then propose a circuit that “transfers” all the depth into ancillae, yielding a final depth that is linear in n at the cost of an exponential number of ancillae. Themain idea of this linear-depth circuit is to implement in parallel all coin operators at the different positions. Reducing the depth exponentially at the cost of having an exponential number of ancillae is a goal which has already been achieved for the problem of loading classical data on a quantum circuit (Araujo in Sci Rep 11:6329, 2021) (notice that such a circuit can be used to load the initial state of the walker). Here, we achieve this goal for the problem of applying a position-dependent coin operator in a discrete-time quantum walk. Finally, we extend the result of Welch (New J Phys 16:033040, 2014) from position-dependent unitaries which are diagonal in the position basis to position-dependent 2 x 2-block-diagonal unitaries: indeed, we show that for a position dependence of the coin operator (the block-diagonal unitary) which is smooth enough, one can find an efficient quantum-circuit implementation approximating the coin operator up to an error epsilon (in terms of the spectral norm), the depth and size of which scale as O(1/epsilon). A typical application of the efficient implementation would be the quantum simulation of a relativistic spin-1/2 particle on a lattice, coupled to a smooth external gauge field; notice that recently, quantum spatial-search schemes have been developed which use gauge fields as the oracle, to mark the vertex to be found (Zylberman in Entropy 23:1441, 2021), (Fredon arXiv:2210.13920). A typical application of the linear-depth circuit would be when there is spatial noise on the coin operator (and hence a non-smooth dependence in the position).
Address [Nzongani, Ugo; Doncecchi, Carlo-Elia; Arnault, Pablo] Univ Paris Saclay, CNRS, INRIA, Lab Methodes Formelles,ENS Paris Saclay, F-91190 Gif Sur Yvette, France, Email: ugo.nzongani@universite-paris-saclay.fr;
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 1570-0755 ISBN Medium
Area Expedition Conference
Notes WOS:001022408900002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5587
Permanent link to this record
 
 
Author Villanueva-Domingo, P.; Ichiki, K.
Title 21 cm forest constraints on primordial black holes Type Journal Article
Year 2023 Publication (down) Publications of the Astronomical Society of Japan Abbreviated Journal Publ. Astron. Soc. Jpn.
Volume 75 Issue SP1 Pages S33-S49
Keywords dark matter; radio lines: ISM
Abstract Primordial black holes (PBHs) as part of the dark matter (DM) would modify the evolution of large-scale structures and the thermal history of the universe. Future 21 cm forest observations, sensitive to small scales and the thermal state of the intergalactic medium (IGM), could probe the existence of such PBHs. In this article, we show that the shot noise isocurvature mode on small scales induced by the presence of PBHs can enhance the amount of low-mass halos, or minihalos, and thus, the number of 21 cm absorption lines. However, if the mass of PBHs is as large as M-PBH greater than or similar to 10 M-circle dot, with an abundant enough fraction of PBHs as DM, f(PBH), the IGM heating due to accretion on to the PBHs counteracts the enhancement due to the isocurvature mode, reducing the number of absorption lines instead. The concurrence of both effects imprints distinctive signatures on the number of absorbers, allowing the abundance of PBHs to be bound. We compute the prospects for constraining PBHs with future 21 cm forest observations, finding achievable competitive upper limits on the abundance as low as f(PBH) similar to 10(-3) at M-PBH = 100 M-circle dot, or even lower at larger masses, in regions of the parameter space unexplored by current probes. The impact of astrophysical X-ray sources on the IGM temperature is also studied, which could potentially weaken the bounds.
Address [Villanueva-Domingo, Pablo] Univ Valencia, Inst Fis Corpuscular IFIC, CSIC, Apartado Correos 22085, E-46071 Valencia, Spain, Email: ichiki@a.phys.nagoya-u.ac.jp
Corporate Author Thesis
Publisher Oxford Univ Press Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0004-6264 ISBN Medium
Area Expedition Conference
Notes WOS:000768441900001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5168
Permanent link to this record