SwePub - sökning: WFRF:(Dietz R)

Numrering	Referens	Omslagsbild	Hitta
1.	Aad, G, et al. (författare) 2015 swepub:Mat__t
2.	Abadie, J., et al. (författare) Implementation and testing of the first prompt search for gravitational wave transients with electromagnetic counterparts 2012 Ingår i: Astronomy & Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 539 Tidskriftsartikel (refereegranskat)abstract Aims. A transient astrophysical event observed in both gravitational wave (GW) and electromagnetic (EM) channels would yield rich scientific rewards. A first program initiating EM follow-ups to possible transient GW events has been developed and exercised by the LIGO and Virgo community in association with several partners. In this paper, we describe and evaluate the methods used to promptly identify and localize GW event candidates and to request images of targeted sky locations. Methods. During two observing periods (Dec. 17, 2009 to Jan. 8, 2010 and Sep. 2 to Oct. 20, 2010), a low-latency analysis pipeline was used to identify GW event candidates and to reconstruct maps of possible sky locations. A catalog of nearby galaxies and Milky Way globular clusters was used to select the most promising sky positions to be imaged, and this directional information was delivered to EM observatories with time lags of about thirty minutes. A Monte Carlo simulation has been used to evaluate the low-latency GW pipeline's ability to reconstruct source positions correctly. Results. For signals near the detection threshold, our low-latency algorithms often localized simulated GW burst signals to tens of square degrees, while neutron star/neutron star inspirals and neutron star/black hole inspirals were localized to a few hundred square degrees. Localization precision improves for moderately stronger signals. The correct sky location of signals well above threshold and originating from nearby galaxies may be observed with similar to 50% or better probability with a few pointings of wide-field telescopes.
3.	Adrian-Martinez, S., et al. (författare) A first search for coincident gravitational waves and high energy neutrinos using LIGO, Virgo and ANTARES data from 2007 2013 Ingår i: Journal of Cosmology and Astroparticle Physics. - : IOP Publishing. - 1475-7516. ; :6 Tidskriftsartikel (refereegranskat)abstract We present the results of the first search for gravitational wave bursts associated with high energy neutrinos. Together, these messengers could reveal new, hidden sources that are not observed by conventional photon astronomy, particularly at high energy. Our search uses neutrinos detected by the underwater neutrino telescope ANTARES in its 5 line configuration during the period January - September 2007, which coincided with the fifth and first science runs of LIGO and Virgo, respectively. The LIGO-Virgo data were analysed for candidate gravitational-wave signals coincident in time and direction with the neutrino events. No significant coincident events were observed. We place limits on the density of joint high energy neutrino - gravitational wave emission events in the local universe, and compare them with densities of merger and core-collapse events.
4.	Abadie, J., et al. (författare) All-sky search for periodic gravitational waves in the full S5 LIGO data 2012 Ingår i: Physical Review D (Particles, Fields, Gravitation and Cosmology). - 1550-2368. ; 85:2 Tidskriftsartikel (refereegranskat)abstract We report on an all-sky search for periodic gravitational waves in the frequency band 50-800 Hz and with the frequency time derivative in the range of 0 through -6 x 10(-9) Hz/s. Such a signal could be produced by a nearby spinning and slightly nonaxisymmetric isolated neutron star in our Galaxy. After recent improvements in the search program that yielded a 10x increase in computational efficiency, we have searched in two years of data collected during LIGO's fifth science run and have obtained the most sensitive all-sky upper limits on gravitational-wave strain to date. Near 150 Hz our upper limit on worst-case linearly polarized strain amplitude h(0) is 1 x 10(-24), while at the high end of our frequency range we achieve a worst-case upper limit of 3.8 x 10(-24) for all polarizations and sky locations. These results constitute a factor of 2 improvement upon previously published data. A new detection pipeline utilizing a loosely coherent algorithm was able to follow up weaker outliers, increasing the volume of space where signals can be detected by a factor of 10, but has not revealed any gravitational-wave signals. The pipeline has been tested for robustness with respect to deviations from the model of an isolated neutron star, such as caused by a low-mass or long-period binary companion.
5.	Abadie, J., et al. (författare) Search for Gravitational Waves Associated with Gamma-Ray Bursts during LIGO Science Run 6 and Virgo Science Runs 2 and 3 2012 Ingår i: Astrophysical Journal. - 0004-637X. ; 760:1 Tidskriftsartikel (refereegranskat)abstract We present the results of a search for gravitational waves associated with 154 gamma-ray bursts (GRBs) that were detected by satellite-based gamma-ray experiments in 2009-2010, during the sixth LIGO science run and the second and third Virgo science runs. We perform two distinct searches: a modeled search for coalescences of either two neutron stars or a neutron star and black hole, and a search for generic, unmodeled gravitational-wave bursts. We find no evidence for gravitational-wave counterparts, either with any individual GRB in this sample or with the population as a whole. For all GRBs we place lower bounds on the distance to the progenitor, under the optimistic assumption of a gravitational-wave emission energy of 10(-2) M-circle dot c(2) at 150 Hz, with a median limit of 17 Mpc. For short-hard GRBs we place exclusion distances on binary neutron star and neutron-star-black-hole progenitors, using astrophysically motivated priors on the source parameters, with median values of 16 Mpc and 28 Mpc, respectively. These distance limits, while significantly larger than for a search that is not aided by GRB satellite observations, are not large enough to expect a coincidence with a GRB. However, projecting these exclusions to the sensitivities of Advanced LIGO and Virgo, which should begin operation in 2015, we find that the detection of gravitational waves associated with GRBs will become quite possible.
6.	Abadie, J., et al. (författare) Search for gravitational waves from low mass compact binary coalescence in LIGO's sixth science run and Virgo's science runs 2 and 3 2012 Ingår i: Physical Review D (Particles, Fields, Gravitation and Cosmology). - 1550-2368. ; 85:8 Tidskriftsartikel (refereegranskat)abstract We report on a search for gravitational waves from coalescing compact binaries using LIGO and Virgo observations between July 7, 2009, and October 20, 2010. We searched for signals from binaries with total mass between 2 and 25M(circle dot); this includes binary neutron stars, binary black holes, and binaries consisting of a black hole and neutron star. The detectors were sensitive to systems up to 40 Mpc distant for binary neutron stars, and further for higher mass systems. No gravitational-wave signals were detected. We report upper limits on the rate of compact binary coalescence as a function of total mass, including the results from previous LIGO and Virgo observations. The cumulative 90% confidence rate upper limits of the binary coalescence of binary neutron star, neutron star-black hole, and binary black hole systems are 1.3 x 10(-4), 3.1 x 10(-5), and 6.4 x 10(-6) Mpc(-3) yr(-1), respectively. These upper limits are up to a factor 1.4 lower than previously derived limits. We also report on results from a blind injection challenge.
7.	Abadie, J., et al. (författare) All-sky search for gravitational-wave bursts in the second joint LIGO-Virgo run 2012 Ingår i: Physical Review D (Particles, Fields, Gravitation and Cosmology). - 1550-2368. ; 85:12 Tidskriftsartikel (refereegranskat)abstract We present results from a search for gravitational-wave bursts in the data collected by the LIGO and Virgo detectors between July 7, 2009 and October 20, 2010: data are analyzed when at least two of the three LIGO-Virgo detectors are in coincident operation, with a total observation time of 207 days. The analysis searches for transients of duration less than or similar to 1 s over the frequency band 64-5000 Hz, without other assumptions on the signal waveform, polarization, direction or occurrence time. All identified events are consistent with the expected accidental background. We set frequentist upper limits on the rate of gravitational-wave bursts by combining this search with the previous LIGO-Virgo search on the data collected between November 2005 and October 2007. The upper limit on the rate of strong gravitational-wave bursts at the Earth is 1.3 events per year at 90% confidence. We also present upper limits on source rate density per year and Mpc(3) for sample populations of standard-candle sources. As in the previous joint run, typical sensitivities of the search in terms of the root-sum-squared strain amplitude for these waveforms lie in the range similar to 5 x 10(-22) Hz(-1/2) to similar to 1 x 10(-20) Hz(-1/2). The combination of the two joint runs entails the most sensitive all-sky search for generic gravitational-wave bursts and synthesizes the results achieved by the initial generation of interferometric detectors.
8.	Abadie, J., et al. (författare) First low-latency LIGO plus Virgo search for binary inspirals and their electromagnetic counterparts 2012 Ingår i: Astronomy & Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 541 Tidskriftsartikel (refereegranskat)abstract Aims. The detection and measurement of gravitational-waves from coalescing neutron-star binary systems is an important science goal for ground-based gravitational-wave detectors. In addition to emitting gravitational-waves at frequencies that span the most sensitive bands of the LIGO and Virgo detectors, these sources are also amongst the most likely to produce an electromagnetic counterpart to the gravitational-wave emission. A joint detection of the gravitational-wave and electromagnetic signals would provide a powerful new probe for astronomy. Methods. During the period between September 19 and October 20, 2010, the first low-latency search for gravitational-waves from binary inspirals in LIGO and Virgo data was conducted. The resulting triggers were sent to electromagnetic observatories for followup. We describe the generation and processing of the low-latency gravitational-wave triggers. The results of the electromagnetic image analysis will be described elsewhere. Results. Over the course of the science run, three gravitational-wave triggers passed all of the low-latency selection cuts. Of these, one was followed up by several of our observational partners. Analysis of the gravitational-wave data leads to an estimated false alarm rate of once every 6.4 days, falling far short of the requirement for a detection based solely on gravitational-wave data.
9.	Abadie, J., et al. (författare) Search for gravitational waves from intermediate mass binary black holes 2012 Ingår i: Physical Review D (Particles, Fields, Gravitation and Cosmology). - 1550-2368. ; 85:10 Tidskriftsartikel (refereegranskat)abstract We present the results of a weakly modeled burst search for gravitational waves from mergers of nonspinning intermediate mass black holes in the total mass range 100-450 M-circle dot and with the component mass ratios between 1: and 4:1. The search was conducted on data collected by the LIGO and Virgo detectors between November of 2005 and October of 2007. No plausible signals were observed by the search which constrains the astrophysical rates of the intermediate mass black holes mergers as a function of the component masses. In the most efficiently detected bin centered on 88 + 88 M-circle dot, for nonspinning sources, the rate density upper limit is 0.13 per Mpc(3) per Myr at the 90% confidence level.
10.	Abadie, J., et al. (författare) Upper limits on a stochastic gravitational-wave background using LIGO and Virgo interferometers at 600-1000 Hz 2012 Ingår i: Physical Review D (Particles, Fields, Gravitation and Cosmology). - 1550-2368. ; 85:12 Tidskriftsartikel (refereegranskat)abstract A stochastic background of gravitational waves is expected to arise from a superposition of many incoherent sources of gravitational waves, of either cosmological or astrophysical origin. This background is a target for the current generation of ground-based detectors. In this article we present the first joint search for a stochastic background using data from the LIGO and Virgo interferometers. In a frequency band of 600-1000 Hz, we obtained a 95% upper limit on the amplitude of Omega(GW)(f) = Omega(3)(f/900 Hz)(3), of Omega(3) < 0.32, assuming a value of the Hubble parameter of h(100) = 0.71. These new limits are a factor of seven better than the previous best in this frequency band.
11.	Aasi, J., et al. (författare) Einstein@Home all-sky search for periodic gravitational waves in LIGO S5 data 2013 Ingår i: Physical Review D (Particles, Fields, Gravitation and Cosmology). - 1550-2368. ; 87:4 Tidskriftsartikel (refereegranskat)abstract This paper presents results of an all-sky search for periodic gravitational waves in the frequency range [50, 1190] Hz and with frequency derivative range of similar to[-20, 1.1] x 10(-10) Hz s(-1) for the fifth LIGO science run (S5). The search uses a noncoherent Hough-transform method to combine the information from coherent searches on time scales of about one day. Because these searches are very computationally intensive, they have been carried out with the Einstein@Home volunteer distributed computing project. Postprocessing identifies eight candidate signals; deeper follow-up studies rule them out. Hence, since no gravitational wave signals have been found, we report upper limits on the intrinsic gravitational wave strain amplitude h(0). For example, in the 0.5 Hz-wide band at 152.5 Hz, we can exclude the presence of signals with h(0) greater than 7.6 x 10(-25) at a 90% confidence level. This search is about a factor 3 more sensitive than the previous Einstein@Home search of early S5 LIGO data.
12.	Aasi, J., et al. (författare) Search for gravitational waves from binary black hole inspiral, merger, and ringdown in LIGO-Virgo data from 2009-2010 2013 Ingår i: Physical Review D (Particles, Fields, Gravitation and Cosmology). - 1550-2368. ; 87:2 Tidskriftsartikel (refereegranskat)abstract We report a search for gravitational waves from the inspiral, merger and ringdown of binary black holes (BBH) with total mass between 25 and 100 solar masses, in data taken at the LIGO and Virgo observatories between July 7, 2009 and October 20, 2010. The maximum sensitive distance of the detectors over this period for a (20, 20)M-circle dot coalescence was 300 Mpc. No gravitational wave signals were found. We thus report upper limits on the astrophysical coalescence rates of BBH as a function of the component masses for nonspinning components, and also evaluate the dependence of the search sensitivity on component spins aligned with the orbital angular momentum. We find an upper limit at 90% confidence on the coalescence rate of BBH with nonspinning components of mass between 19 and 28M(circle dot) of 3:3 x 10(-7) mergers Mpc(-3) yr(-1).
13.	Aasi, J., et al. (författare) The characterization of Virgo data and its impact on gravitational-wave searches 2012 Ingår i: Classical and Quantum Gravity. - : IOP Publishing. - 1361-6382 .- 0264-9381. ; 29:15 Tidskriftsartikel (refereegranskat)abstract Between 2007 and 2010 Virgo collected data in coincidence with the LIGO and GEO gravitational-wave (GW) detectors. These data have been searched for GWs emitted by cataclysmic phenomena in the universe, by non-axisymmetric rotating neutron stars or from a stochastic background in the frequency band of the detectors. The sensitivity of GW searches is limited by noise produced by the detector or its environment. It is therefore crucial to characterize the various noise sources in a GW detector. This paper reviews the Virgo detector noise sources, noise propagation, and conversion mechanisms which were identified in the three first Virgo observing runs. In many cases, these investigations allowed us to mitigate noise sources in the detector, or to selectively flag noise events and discard them from the data. We present examples from the joint LIGO-GEO-Virgo GW searches to show how well noise transients and narrow spectral lines have been identified and excluded from the Virgo data. We also discuss how detector characterization can improve the astrophysical reach of GW searches.
14.	Evans, P. A., et al. (författare) Swift Follow-up Observations of Candidate Gravitational-wave Transient Events 2012 Ingår i: The Astrophysical Journal Supplement Series. - : American Astronomical Society. - 0067-0049 .- 1538-4365. ; 203:2 Tidskriftsartikel (refereegranskat)abstract We present the first multi-wavelength follow-up observations of two candidate gravitational-wave (GW) transient events recorded by LIGO and Virgo in their 2009-2010 science run. The events were selected with low latency by the network of GW detectors (within less than 10 minutes) and their candidate sky locations were observed by the Swift observatory (within 12 hr). Image transient detection was used to analyze the collected electromagnetic data, which were found to be consistent with background. Off-line analysis of the GW data alone has also established that the selected GW events show no evidence of an astrophysical origin; one of them is consistent with background and the other one was a test, part of a "blind injection challenge." With this work we demonstrate the feasibility of rapid follow-ups of GW transients and establish the sensitivity improvement joint electromagnetic and GW observations could bring. This is a first step toward an electromagnetic follow-up program in the regime of routine detections with the advanced GW instruments expected within this decade. In that regime, multi-wavelength observations will play a significant role in completing the astrophysical identification of GW sources. We present the methods and results from this first combined analysis and discuss its implications in terms of sensitivity for the present and future instruments.
15.	Aasi, J., et al. (författare) Parameter estimation for compact binary coalescence signals with the first generation gravitational-wave detector network 2013 Ingår i: Physical Review D (Particles, Fields, Gravitation and Cosmology). - 1550-2368. ; 88:6 Tidskriftsartikel (refereegranskat)abstract Compact binary systems with neutron stars or black holes are one of the most promising sources for ground-based gravitational-wave detectors. Gravitational radiation encodes rich information about source physics; thus parameter estimation and model selection are crucial analysis steps for any detection candidate events. Detailed models of the anticipated waveforms enable inference on several parameters, such as component masses, spins, sky location and distance, that are essential for new astrophysical studies of these sources. However, accurate measurements of these parameters and discrimination of models describing the underlying physics are complicated by artifacts in the data, uncertainties in the waveform models and in the calibration of the detectors. Here we report such measurements on a selection of simulated signals added either in hardware or software to the data collected by the two LIGO instruments and the Virgo detector during their most recent joint science run, including a "blind injection'' where the signal was not initially revealed to the collaboration. We exemplify the ability to extract information about the source physics on signals that cover the neutron-star and black-hole binary parameter space over the component mass range 1M(circle dot)-25M(circle dot) and the full range of spin parameters. The cases reported in this study provide a snapshot of the status of parameter estimation in preparation for the operation of advanced detectors.
16.	Burtness, B, et al. (författare) Afatinib vs Placebo as Adjuvant Therapy After Chemoradiotherapy in Squamous Cell Carcinoma of the Head and Neck: A Randomized Clinical Trial 2019 Ingår i: JAMA oncology. - : American Medical Association (AMA). - 2374-2445 .- 2374-2437. ; 5:8, s. 1170-1180 Tidskriftsartikel (refereegranskat)
17.	Kelly, ME, et al. (författare) Simultaneous pelvic exenteration and liver resection for primary rectal cancer with synchronous liver metastases: results from the PelvEx Collaborative 2020 Ingår i: Colorectal disease : the official journal of the Association of Coloproctology of Great Britain and Ireland. - : Wiley. - 1463-1318 .- 1462-8910. ; 22:10, s. 1258-1262 Tidskriftsartikel (refereegranskat)
18.	West, CT, et al. (författare) Beating the empty pelvis syndrome: the PelvEx Collaborative core outcome set study protocol 2024 Ingår i: BMJ open. - 2044-6055. ; 14:2, s. e076538- Tidskriftsartikel (refereegranskat)
19.	West, CT, et al. (författare) Empty pelvis syndrome: PelvEx Collaborative guideline proposal 2023 Ingår i: The British journal of surgery. - 1365-2168. ; 110:12, s. 1730-1731 Tidskriftsartikel (refereegranskat)
20.	Chok, AY, et al. (författare) Perioperative management and anaesthetic considerations in pelvic exenterations using Delphi methodology: results from the PelvEx Collaborative 2021 Ingår i: BJS open. - : Wiley. - 2474-9842. ; 5:1 Tidskriftsartikel (refereegranskat)
21.	Dudurych, I, et al. (författare) Predicting outcomes of pelvic exenteration using machine learning 2020 Ingår i: Colorectal disease : the official journal of the Association of Coloproctology of Great Britain and Ireland. - : Wiley. - 1463-1318 .- 1462-8910. ; 22:12, s. 1933-1940 Tidskriftsartikel (refereegranskat)
22.	Praena, J., et al. (författare) Measurement and resonance analysis of the 33S(n,alpha)30Si cross section at the CERN n_TOF facility in the energy region from 10 to 300 keV 2018 Ingår i: Phys. Rev. C. - : American Physical Society. ; 97 Tidskriftsartikel (refereegranskat)
23.	Voogt, ELK, et al. (författare) Induction chemotherapy followed by chemoradiotherapy versus chemoradiotherapy alone as neoadjuvant treatment for locally recurrent rectal cancer: study protocol of a multicentre, open-label, parallel-arms, randomized controlled study (PelvEx II) 2021 Ingår i: BJS open. - : Wiley. - 2474-9842. ; 5:3 Tidskriftsartikel (refereegranskat)
24.	Aalbers, AGJ, et al. (författare) The empty pelvis syndrome: a core data set from the PelvEx collaborative 2024 Ingår i: The British journal of surgery. - 1365-2168. ; 111:3 Tidskriftsartikel (refereegranskat)
25.	Alcayne, V., et al. (författare) A Segmented Total Energy Detector (sTED) optimized for (n,ϒ) cross-section measurements at n_TOF EAR2 2024 Ingår i: Radiation Physics and Chemistry. - : Elsevier. - 0969-806X .- 1879-0895. ; 217 Tidskriftsartikel (refereegranskat)abstract The neutron time-of-flight facility n_TOF 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 n_TOF EAR2.
26.	Balibrea-Correa, J., et al. (författare) First measurement of the 94Nb(n,γ) cross section at the CERN n_TOF facility 2023 Ingår i: EPJ Web of Conferences. - : EDP Sciences. - 2100-014X. ; 279 Tidskriftsartikel (refereegranskat)abstract One of the crucial ingredients for the improvement of stellar models is the accurate knowledge of neutron capture cross-sections for the different isotopes involved in the s-,r- and i- processes. These measurements can shed light on existing discrepancies between observed and predicted isotopic abundances and help to constrain the physical conditions where these reactions take place along different stages of stellar evolution.In the particular case of the radioactive 94Nb, the 94Nb(n,γ) cross-section could play a role in the determination of the s-process production of 94Mo in AGB stars, which presently cannot be reproduced by state-of-the-art stellar models. There are no previous 94Nb(n,γ) experimental data for the resolved and unresolved resonance regions mainly due to the difficulties in producing highquality samples and also due to limitations in conventional detection systems commonly used in time-of-flight experiments.Motivated by this situation, a first measurement of the 94Nb(n,γ) reaction was carried out at CERN n_TOF, thereby exploiting the high luminosity of the EAR2 area in combination with a new detection system of small-volume C6D6-detectors and a high quality 94Nb-sample. The latter was based on hyper-pure 93Nb material activated at the high-flux reactor of ILL-Grenoble. An innovative ring-configuration detection system in close geometry around the capture sample allowed us to significantly enhance the signal-to-background ratio. This set-up was supplemented with two conventional C6D6-detectors and a highresolution LaCl3(Ce)-detector, which will be employed for addressing reliably systematic effects and uncertainties.At the current status of the data analysis, 18 resonance in 94Nb+n have been observed for the first time in the neutron energy range from thermal up to 10 keV.
27.	Domingo-Pardo, C., et al. (författare) Compton imaging for enhanced sensitivity (n,gamma) cross section TOF experiments : Status and prospects 2023 Ingår i: 15TH INTERNATIONAL CONFERENCE ON NUCLEAR DATA FOR SCIENCE AND TECHNOLOGY, ND2022. - : EDP Sciences. Konferensbidrag (refereegranskat)abstract Radiative neutron-capture cross sections are of pivotal importance in many fields such as nucle-osynthesis studies or innovative reactor technologies. A large number of isotopes have been measured with high accuracy, but there are still a large number of relevant isotopes whose cross sections could not be experimentally determined yet, at least with sufficient accuracy and completeness, owing to limitations in detection techniques, sample production methods or in the facilities themselves. In the context of the HYMNS (High-sensitivitY Measurements of key stellar Nucleo-Synthesis reactions) project over the last six years we have developed a novel detection technique aimed at background suppression in radiative neutron-capture time-of-flight measurements. This new technique utilizes a complex detection set-up based on position-sensitive radiation-detectors deployed in a Compton-camera array configuration. The latter enables to implement gamma-ray imaging techniques, which help to disentangle true capture events arising from the sample under study and contaminant background events from the surroundings. A summary on the main developments is given in this contribution together with an update on recent experiments at CERN n_TOF and an outlook on future steps.
28.	Domingo-Pardo, C., et al. (författare) The neutron time-of-flight facility n_TOF at CERN Recent facility upgrades and detector developments 2023 Ingår i: Journal of Physics, Conference Series. - : Institute of Physics (IOP). - 1742-6588 .- 1742-6596. ; 2586 Tidskriftsartikel (refereegranskat)abstract Based on an idea by Carlo Rubbia, the n_TOF facility at CERN has been operating for over 20 years. It is a neutron spallation source, driven by the 20 GeV/c proton beam from the CERN PS accelerator. Neutrons in a very wide energy range (from GeV, down to sub-eV kinetic energy) are generated by a massive Lead spallation target feeding two experimental areas. EAR1, horizonal with respect to the proton beam direction is set at 185 meters from the spallation target. EAR2, on the vertical line from the spallation source, is placed at 20 m. Neutron energies for experiments are selected by the time-of-flight technique (hence the name n_TOF), while the long flight paths ensure a very good energy resolution. Over one hundred experiments have been performed by the n_TOF Collaboration at CERN, with applications ranging from nuclear astrophysics (synthesis of the heavy elements in stars, big bang nucleosynthesis, nuclear cosmo-chronology), to advanced nuclear technologies (nuclear data for applications, nuclear safety), as well as for basic nuclear science (reaction mechanisms, structure and decay of highly excited compound states). During the planned shutdown of the CERN accelerator complex between 2019 and 2021, the facility went through a substantial upgrade with a new target-moderator assembly, refurbishing of the neutron beam lines and experimental areas. An additional measuring and irradiation station (the NEAR Station) has been envisaged and its capabilities for performing material test studies and new physics opportunities are presently explored. An overview of the facility and of the activities performed at CERN is presented in this contribution, with a particular emphasis on the most relevant experiments for nuclear astrophysics.
29.	Dupont, E., et al. (författare) Overview of the dissemination of n_TOF experimental data and resonance parameters 2023 Ingår i: 15TH INTERNATIONAL CONFERENCE ON NUCLEAR DATA FOR SCIENCE AND TECHNOLOGY, ND2022. - : EDP Sciences. Konferensbidrag (refereegranskat)abstract The n_TOF neutron time-of-flight facility at CERN is used for nuclear data measurements. The n_TOF Collaboration works closely with the Nuclear Reaction Data Centres (NRDC) network to disseminate the experimental data through the international EXFOR library. In addition, the Collaboration helps integrate the results in the evaluated library projects. The present contribution describes the dissemination status of n_TOF results, their impact on evaluated libraries and ongoing efforts to provide n_TOF resonance parameters in ENDF-6 format for further use by evaluation projects.
30.	Lerendegui-Marco, J., et al. (författare) New detection systems for an enhanced sensitivity in key stellar (n,γ) measurements 2023 Ingår i: EPJ Web of Conferences. - : EDP Sciences. - 2100-014X. ; 279 Tidskriftsartikel (refereegranskat)abstract Neutron capture cross-section measurements are fundamental in the study of astrophysical phenomena, such as the slow neutron capture (s-) process of nucleosynthesis operating in red-giant and massive stars. However, neutron capture measurements via the time-of-flight (TOF) technique on key s-process nuclei are often challenging. Difficulties arise from the limited mass (∼mg) available and the high sample-related background in the case of the unstable s-process branching points. Measurements on neutron magic nuclei, that act as s-process bottlenecks, are affected by low (n,γ) cross sections and a dominant neutron scattering background. Overcoming these experimental challenges requires the combination of facilities with high instantaneous flux, such as n_TOFEAR2, with detection systems with an enhanced detection sensitivity and high counting rate capabilities. This contribution reviews some of the latest detector developments in detection systems for (n,γ) measurements at n_TOF, such as i-TED, an innovative detection system which exploits the Compton imaging technique to reduce the dominant neutron scattering background and s-TED, a highly segmented total energy detector intended for high flux facilities. The discussion will be illustrated with results of the first measurement of key the s-process branching-point reaction 79Se(n,γ).
31.	Mastromarco, M., et al. (författare) Measurement of the Gd-160(n, gamma) cross section at n_TOF and its medical implications 2023 Ingår i: 15TH INTERNATIONAL CONFERENCE ON NUCLEAR DATA FOR SCIENCE AND TECHNOLOGY, ND2022. - : EDP Sciences. Konferensbidrag (refereegranskat)abstract Neutron-capture reactions on gadolinium isotopes play an important role in several fields of physics, in particular in nuclear Astrophysics for the understanding of the nucleosynthesis of heavy elements (beyond iron) in stars via the s- and r-processes [1] and in nuclear technology. Another important application of gadolinium is linked to the production of terbium, that offers a set of clinically interesting isotopes for theranostics, characterized by complementary physical decay characteristics. In particular, the low -energy beta(-) emitter terbium-161 is very similar to lutetium-177 in terms of half-life (6.89 d), beta(-) - energy and chemical properties. Being a significant emitter of conversion/Auger electrons, greater therapeutic effect can therefore be expected in comparison to Lu-177 [2, 3]. For this reason, in the last decade, the study of the neutron capture reaction Gd-160(n,,gamma)(161) Gd and the subsequent beta(-) - decay in terbium-161 is getting particular attention. As the nuclear data on the Gd-160 neutron capture reaction are quite scarce and inconsistent, a new measurement of the capture cross section of Gd-160 at the CERN neutron Time -Of-Flight facilty was performed in order to provide high resolution, high -accuracy data on this important reaction, in the energy range from thermal to hundreds of keV. In this contribution, the preliminary results of the n_TOF measurement are presented.
32.	Patronis, N., et al. (författare) Status report of the n_TOF facility after the 2nd CERN long shutdown period 2023 Ingår i: EPJ TECHNIQUES AND INSTRUMENTATION. - : Springer Nature. - 2195-7045. ; 10 Tidskriftsartikel (refereegranskat)abstract During the second long shutdown period of the CERN accelerator complex (LS2, 2019-2021), several upgrade activities took place at the n_TOF facility. The most important have been the replacement of the spallation target with a next generation nitrogen-cooled lead target. Additionally, a new experimental area, at a very short distance from the target assembly (the NEAR Station) was established. In this paper, the core commissioning actions of the new installations are described. The improvement in the n_TOF infrastructure was accompanied by several detector development projects. All these upgrade actions are discussed, focusing mostly on the future perspectives of the n_TOF facility. Furthermore, some indicative current and future measurements are briefly reported.
33.	Praena, J., et al. (författare) Preparation and characterization of 33S samples for 33S(n,alpha)30Si cross-section measurements at the n_TOF facility at CERN 2018 Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier BV. - 0168-9002 .- 1872-9576. ; 890, s. 142-147 Tidskriftsartikel (refereegranskat)abstract Thin 33S samples for the study of the 33S(n,alpha)30Si cross-section at the n_TOF facility at CERN were made by thermal evaporation of 33S powder onto a dedicated substrate made of kapton covered with thin layers of copper, chromium and titanium. This method has provided for the first time bare sulfur samples a few centimeters in diameter. The samples have shown an excellent adherence with no mass loss after few years and no sublimation in vacuum at room temperature. The determination of the mass thickness ofÂ 33S has been performed by means of Rutherford backscattering spectrometry. The samples have been successfully tested under neutron irradiation.
34.	Domingo-Pardo, C., et al. (författare) Advances and new ideas for neutron-capture astrophysics experiments at CERN n_TOF 2023 Ingår i: European Physical Journal A. - : Springer. - 1434-6001 .- 1434-601X. ; 59:1 Tidskriftsartikel (refereegranskat)abstract This article presents a few selected developments and future ideas related to the measurement of (n,γ) data of astrophysical interest at CERN n_TOF. The MC-aided analysis methodology for the use of low-efficiency radiation detectors in time-of-flight neutron-capture measurements is discussed, with particular emphasis on the systematic accuracy. Several recent instrumental advances are also presented, such as the development of total-energy detectors with γ-ray imaging capability for background suppression, and the development of an array of small-volume organic scintillators aimed at exploiting the high instantaneous neutron-flux of EAR2. Finally, astrophysics prospects related to the intermediate i neutron-capture process of nucleosynthesis are discussed in the context of the new NEAR activation area.
35.	Figueroa, JD, et al. (författare) Associations of common variants at 1p11.2 and 14q24.1 (RAD51L1) with breast cancer risk and heterogeneity by tumor subtype: findings from the Breast Cancer Association Consortium 2011 Ingår i: Human molecular genetics. - : Oxford University Press (OUP). - 1460-2083 .- 0964-6906. ; 20:23, s. 4693-4706 Tidskriftsartikel (refereegranskat)
36.	Halsey, LG, et al. (författare) Greater male variability in daily energy expenditure develops through puberty 2023 Ingår i: Biology letters. - 1744-957X .- 1744-9561. ; 19:9, s. 20230152- Tidskriftsartikel (refereegranskat)
37.	Lerendegui-Marco, J., et al. (författare) New perspectives for neutron capture measurements in the upgraded CERN-n_TOF Facility 2023 Ingår i: 15th International Conference on Nuclear Data for Science and Technology, ND2022. - : EDP Sciences. Konferensbidrag (refereegranskat)abstract The n_TOF facility has just undergone in 2021 a major upgrade with the installation of its third generation spallation target that has been designed to optimize the performance of the two n_TOF time-of-flight lines. This contribution describes the key features and limitations for capture measurements in the two beam lines prior to the target upgrade and presents first results of (n,gamma) measurements carried out as part of the commissioning of the upgraded facility. In particular, the energy resolution, a key factor for both increasing the signal-to background ratio and obtaining accurate resonance parameters, has been clearly improved for the 20 m long vertical beam-line with the new target design while keeping the remarkably high resolution of the long beamline n_TOF-EAR1. The improvements in the n_TOF neutron beam-lines need to be accompanied by improvements in the instrumentation. A review is given on recent detector R&D projects aimed at tackling the existing challenges and further improving the capabilities of this facility.
38.	Massimi, C., et al. (författare) Neutron-induced cross section measurements 2023 Ingår i: EPJ Web of Conferences. - : EDP Sciences. - 2100-014X. ; 279 Tidskriftsartikel (refereegranskat)abstract Neutron-induced cross sections represent the main nuclear input to models of stellar and Big-Bang nucleosynthesis. While (n,γ) reactions are relevant for the formation of elements heavier than iron, (n,p) and (n,α) reactions can play an important role in specific cases. The time-of-flight method is routinely used at n_TOF to experimentally determine the cross section data. In addition, recent upgrades of the facility will allow the use of activation techniques as well, possibly opening the way to a systematic study of neutron interaction with radioactive isotopes. In the last 20 years n_TOF has provided a large amount of experimental data for Nuclear Astrophysics. Our plan is to carry on challenging measurements and produce nuclear data in the next decades as well.
39.	Mucciola, R., et al. (författare) Neutron capture and total cross-section measurements on Mo-94'95'96 at n_TOF and GELINA 2023 Ingår i: 15th International Conference on Nuclear Data for Science and Technology, ND2022. - : EDP Sciences. Konferensbidrag (refereegranskat)abstract Capture and total cross section measurements for 94'95'96 MO have been performed at the neutron time -of-flight facilities, n_TOF at CERN and GELINA at JRC-Geel. The measurements were performed using isotopically enriched samples with an enrichment above 95% for each of the (94'95'96)M0 isotopes. The capture measurements were performed at n_TOF using C6D6 detectors and a new sTED detector. The transmission measurements were performed at a 10 m station of GELINA using a Li-6 glass neutron detector. Preliminary results of these measurements are presented.
40.	Tagliente, G., et al. (författare) The n_TOF facility at CERN 2024 Ingår i: 16<sup>th</sup> Varenna Conference on Nuclear Reaction Mechanisms (NRM2023). - : EDP Sciences. - 9782759891245 Konferensbidrag (refereegranskat)abstract The neutron Time-of-Flight facility (n_TOF) is an innovative facility operative since 2001 at CERN, with three experimental areas. In this paper the n_TOF facility will be described, together with the upgrade of the facility during the Long Shutdown 2 at CERN. The main features of the detectors used for capture fission cross section measurements will be presented with perspectives for the future measurements.
41.	Alcayne, V., et al. (författare) A segmented total energy detector (sTED) for (n, gamma) cross section measurements at n_TOF EAR2 2023 Ingår i: 15TH INTERNATIONAL CONFERENCE ON NUCLEAR DATA FOR SCIENCE AND TECHNOLOGY, ND2022. - : EDP Sciences. Konferensbidrag (refereegranskat)abstract The neutron time-of-flight facility n_TOF is characterised by its high instantaneous neutron intensity, high resolution and broad neutron energy spectra, specially conceived for neutron-induced reaction cross section measurements. Two Time-Of-Flight (TOR) experimental areas are available at the facility: experimental area 1 (EAR1), located at the end of the 185 m horizontal flight path from the spallation target, and experimental area 2 (EAR2), placed at 20 m from the target in the vertical direction. The neutron fluence in EAR2 is similar to 300 times more intense than in EARL in the relevant time-of-flight window. EAR2 was designed to carry out challenging cross-section measurements with low mass samples (approximately 1 mg), reactions with small cross-sections or/and highly radioactive samples. The high instantaneous fluence of EAR2 results in high counting rates that challenge the existing capture systems. Therefore, the sTED detector has been designed to mitigate these effects. In 2021, a dedicated campaign was done validating the performance of the detector up to at least 300 keV neutron energy. After this campaign, the detector has been used to perform various capture cross section measurements at n_TOF EAR2.
42.	Garcia-Infantes, F., et al. (författare) First high resolution measurement of neutron capture resonances in Yb-176 at the n_TOF CERN facility. 2023 Ingår i: 15TH INTERNATIONAL CONFERENCE ON NUCLEAR DATA FOR SCIENCE AND TECHNOLOGY, ND2022. - : EDP Sciences. Konferensbidrag (refereegranskat)abstract Several international agencies recommend the study of new routes and new facilities for producing radioisotopes with application to nuclear medicine. Lu-177 is a versatile radioisotope used for therapy and diagnosis (theranostics) of cancer with good success in neuroendocrine tumours that is being studied to be applied to a wider range of tumours. Lu-177 is produced in few nuclear reactors mainly by the neutron capture on Lu-176. However, it could be produced at high -intensity accelerator-based neutron facilities. The energy of the neutrons in accelerator-based neutron facilities is higher than in thermal reactors. Thus, experimental data on the Yb-176(n,(sic)) cross-section in the eV and keV region are mandatory to calculate accurately the production of Yb-177, which beta decays to 177Lu. At present, there are not experimental data available from thermal to 3 keV of the Yb-176(n,(sic)) cross-section. In addition, there is no data in the resolved resonance region (RRR). This contribution shows the first results of the Yb-176 capture measurement performed at the n_TOF facility at CERN.
43.	Kelly, ME, et al. (författare) Changing outcomes following pelvic exenteration for locally advanced and recurrent rectal cancer 2019 Ingår i: BJS open. - : Oxford University Press (OUP). - 2474-9842. ; 3:4, s. 516-520 Tidskriftsartikel (refereegranskat)
44.	Kelly, ME, et al. (författare) Pelvic Exenteration for Advanced Nonrectal Pelvic Malignancy 2019 Ingår i: Annals of surgery. - 1528-1140. ; 270:5, s. 899-905 Tidskriftsartikel (refereegranskat)
45.	Kögler, T., et al. (författare) Fast-neutron-induced fission cross section of Pu 242 measured at the neutron time-of-flight facility nELBE 2019 Ingår i: Physical Review C. - 2469-9985. ; 99:2 Tidskriftsartikel (refereegranskat)abstract The fast-neutron-induced fission cross section of Pu242 was measured at the neutron time-of-flight facility nELBE. A parallel-plate fission ionization chamber with novel, homogeneous, large-area Pu242 deposits on Si-wafer backings was used to determine this quantity relative to the IAEA neutron cross-section standard U235(n,f) in the energy range of 0.5 to 10 MeV. The number of target nuclei was determined from the measured spontaneous fission rate of Pu242. This helps to reduce the influence of the fission fragment detection efficiency on the cross section. Neutron transport simulations performed with geant4, mcnp6, and fluka2011 are used to correct the cross-section data for neutron scattering. In the reported energy range the systematic uncertainty is below 2.7% and on average the statistical uncertainty is 4.9%. The determined results show an agreement within 0.67(16)% to recently published data and a good accordance to current evaluated data sets.
46.	Pavon-Rodriguez, J. A., et al. (författare) Characterisation of the n_TOF 20 m beam line at CERN with the new spallation target 2023 Ingår i: 15TH INTERNATIONAL CONFERENCE ON NUCLEAR DATA FOR SCIENCE AND TECHNOLOGY, ND2022. - : EDP Sciences. Konferensbidrag (refereegranskat)abstract The n_TOF facility hosts CERN's pulsed neutron source, comprising two beam lines of different flight paths and one activation station. It is based on a proton beam delivered by the PS accelerator impinging on a lead spallation target. During Long Shutdown 2 (LS2) at CERN (2019-2021), a major upgrade of the spallation target was carried out in order to optimize the performances of the neutron beam. Therefore, the characteristics of n_TOF two experimental areas were investigated in detail. In this work, the focus is on the second experimental area (EAR2), located 20 m above the spallation target. Preliminary results of the neutron energy distribution and beam line energy resolution are presented, compared to previous experimental campaigns and Monte Carlo simulations with the FLUKA code. Moreover, preliminary results of the spatial beam profile measurements are shown.
47.	Stamati, M. E., et al. (författare) The n_TOF NEAR Station Commissioning and first physics case 2023 Ingår i: 15TH INTERNATIONAL CONFERENCE ON NUCLEAR DATA FOR SCIENCE AND TECHNOLOGY, ND2022. - : EDP Sciences. Konferensbidrag (refereegranskat)abstract The NEAR Station is a new experimental area developed at the n_TOF Facility at CERN. The activation station of NEAR underwent a characterization of the beam following the installation of the new n_TOF Spallation Target. The commissioning of the neutron beam comprises a set of simulations made with the FLUKA code and experimental verification. The experimental determination of the neutron spectrum was made using activation techniques with three separate set-ups. Two set-ups were based on the Multi-foil Activation technique (MAM-1 and MAM-2), and the third set-up relied on the process of neutron moderation and activation of a single material (ANTILoPE). The three set-ups are presented. Also the present plans and future perspectives of the activation station of NEAR are discussed.
48.	Acs, B, et al. (författare) Systematically higher Ki67 scores on core biopsy samples compared to corresponding resection specimen in breast cancer: a multi-operator and multi-institutional study 2022 Ingår i: Modern pathology : an official journal of the United States and Canadian Academy of Pathology, Inc. - : Elsevier BV. - 1530-0285. ; 35:10, s. 1362-1369 Tidskriftsartikel (refereegranskat)
49.	Kroon, HM, et al. (författare) Palliative pelvic exenteration: A systematic review of patient-centered outcomes 2019 Ingår i: European journal of surgical oncology : the journal of the European Society of Surgical Oncology and the British Association of Surgical Oncology. - : Elsevier BV. - 1532-2157 .- 0748-7983. ; 45:10, s. 1787-1795 Tidskriftsartikel (refereegranskat)
50.	Liu, X. D., et al. (författare) Origin and expansion of the world's most widespread pinniped: Range-wide population genomics of the harbour seal (Phoca vitulina) 2022 Ingår i: Molecular Ecology. - : Wiley. - 0962-1083 .- 1365-294X. ; 31:6, s. 1682-1699 Tidskriftsartikel (refereegranskat)abstract The harbour seal (Phoca vitulina) is the most widely distributed pinniped, occupying a wide variety of habitats and climatic zones across the Northern Hemisphere. Intriguingly, the harbour seal is also one of the most philopatric seals, raising questions as to how it colonized its current range. To shed light on the origin, remarkable range expansion, population structure and genetic diversity of this species, we used genotyping-by-sequencing to analyse similar to 13,500 biallelic single nucleotide polymorphisms from 286 individuals sampled from 22 localities across the species' range. Our results point to a Northeast Pacific origin of the harbour seal, colonization of the North Atlantic via the Canadian Arctic, and subsequent stepping-stone range expansions across the North Atlantic from North America to Europe, accompanied by a successive loss of genetic diversity. Our analyses further revealed a deep divergence between modern North Pacific and North Atlantic harbour seals, with finer-scale genetic structure at regional and local scales consistent with strong philopatry. The study provides new insights into the harbour seal's remarkable ability to colonize and adapt to a wide range of habitats. Furthermore, it has implications for current harbour seal subspecies delineations and highlights the need for international and national red lists and management plans to ensure the protection of genetically and demographically isolated populations.

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