| Records |
| Author |
Coloma, P.; Huber, P.; Schwetz, T. |
| Title |
Statistical interpretation of sterile neutrino oscillation searches at reactors |
Type |
Journal Article |
| Year |
2021 |
Publication |
European Physical Journal C |
Abbreviated Journal |
Eur. Phys. J. C |
| Volume |
81 |
Issue |
1 |
Pages |
2 - 13pp |
Keywords  |
|
| Abstract |
A considerable experimental effort is currently under way to test the persistent hints for oscillations due to an eV-scale sterile neutrino in the data of various reactor neutrino experiments. The assessment of the statistical significance of these hints is usually based on Wilks' theorem, whereby the assumption is made that the log-likelihood is chi 2-distributed. However, it is well known that the preconditions for the validity of Wilks' theorem are not fulfilled for neutrino oscillation experiments. In this work we derive a simple asymptotic form of the actual distribution of the log-likelihood based on reinterpreting the problem as fitting white Gaussian noise. From this formalism we show that, even in the absence of a sterile neutrino, the expectation value for the maximum likelihood estimate of the mixing angle remains non-zero with attendant large values of the log-likelihood. Our analytical results are then confirmed by numerical simulations of a toy reactor experiment. Finally, we apply this framework to the data of the Neutrino-4 experiment and show that the null hypothesis of no-oscillation is rejected at the 2.6 sigma level, compared to 3.2 sigma obtained under the assumption that Wilks' theorem applies. |
| Address |
[Coloma, Pilar] Univ Autonoma Madrid, CSIC, Inst Fis Teor UAM, Calle Nicolas Cabrera 13-15, Madrid 28049, Spain, Email: pilar.coloma@ift.csic.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:000606481000002 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
4680 |
| Permanent link to this record |
| |
|
| |
| Author |
Schaffter, T. et al; Albiol, F.; Caballero, L. |
| Title |
Evaluation of Combined Artificial Intelligence and Radiologist Assessment to Interpret Screening Mammograms |
Type |
Journal Article |
| Year |
2020 |
Publication |
JAMA Network Open |
Abbreviated Journal |
JAMA Netw. Open |
| Volume |
3 |
Issue |
3 |
Pages |
e200265 - 15pp |
| Keywords |
|
| Abstract |
Importance Mammography screening currently relies on subjective human interpretation. Artificial intelligence (AI) advances could be used to increase mammography screening accuracy by reducing missed cancers and false positives. Objective To evaluate whether AI can overcome human mammography interpretation limitations with a rigorous, unbiased evaluation of machine learning algorithms. Design, Setting, and Participants In this diagnostic accuracy study conducted between September 2016 and November 2017, an international, crowdsourced challenge was hosted to foster AI algorithm development focused on interpreting screening mammography. More than 1100 participants comprising 126 teams from 44 countries participated. Analysis began November 18, 2016. Main Outcomes and Measurements Algorithms used images alone (challenge 1) or combined images, previous examinations (if available), and clinical and demographic risk factor data (challenge 2) and output a score that translated to cancer yes/no within 12 months. Algorithm accuracy for breast cancer detection was evaluated using area under the curve and algorithm specificity compared with radiologists' specificity with radiologists' sensitivity set at 85.9% (United States) and 83.9% (Sweden). An ensemble method aggregating top-performing AI algorithms and radiologists' recall assessment was developed and evaluated. Results Overall, 144231 screening mammograms from 85580 US women (952 cancer positive <= 12 months from screening) were used for algorithm training and validation. A second independent validation cohort included 166578 examinations from 68008 Swedish women (780 cancer positive). The top-performing algorithm achieved an area under the curve of 0.858 (United States) and 0.903 (Sweden) and 66.2% (United States) and 81.2% (Sweden) specificity at the radiologists' sensitivity, lower than community-practice radiologists' specificity of 90.5% (United States) and 98.5% (Sweden). Combining top-performing algorithms and US radiologist assessments resulted in a higher area under the curve of 0.942 and achieved a significantly improved specificity (92.0%) at the same sensitivity. Conclusions and Relevance While no single AI algorithm outperformed radiologists, an ensemble of AI algorithms combined with radiologist assessment in a single-reader screening environment improved overall accuracy. This study underscores the potential of using machine learning methods for enhancing mammography screening interpretation. Question How do deep learning algorithms perform compared with radiologists in screening mammography interpretation? Findings In this diagnostic accuracy study using 144231 screening mammograms from 85580 women from the United States and 166578 screening mammograms from 68008 women from Sweden, no single artificial intelligence algorithm outperformed US community radiologist benchmarks; including clinical data and prior mammograms did not improve artificial intelligence performance. However, combining best-performing artificial intelligence algorithms with single-radiologist assessment demonstrated increased specificity. Meaning Integrating artificial intelligence to mammography interpretation in single-radiologist settings could yield significant performance improvements, with the potential to reduce health care system expenditures and address resource scarcity experienced in population-based screening programs. This diagnostic accuracy study evaluates whether artificial intelligence can overcome human mammography interpretation limits with a rigorous, unbiased evaluation of machine learning algorithms. |
| Address |
[Schaffter, Thomas; Hoff, Bruce; Yu, Thomas; Neto, Elias Chaibub; Friend, Stephen; Guinney, Justin] Sage Bionetworks, Computat Oncol, Seattle, WA USA, Email: gustavo@us.ibm.com |
| Corporate Author |
|
Thesis |
|
| Publisher |
Amer Medical Assoc |
Place of Publication |
|
Editor |
|
| Language |
English |
Summary Language |
|
Original Title |
|
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2574-3805 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
WOS:000519249800002 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
4683 |
| Permanent link to this record |
| |
|
| |
| Author |
LHCb Collaboration (Aaij, R. et al); Henry, L.; Jashal, B.K.; Martinez-Vidal, F.; Oyanguren, A.; Remon Alepuz, C.; Ruiz Vidal, J. |
| Title |
Observation of a new Xi(0)(b) state |
Type |
Journal Article |
| Year |
2021 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
| Volume |
103 |
Issue |
1 |
Pages |
012004 - 17pp |
| Keywords |
|
| Abstract |
Using a proton-proton collision data sample collected by the LHCb experiment, corresponding to an integrated luminosity of 8.5 fb(-1), the observation of a new excited Xi(0)(b) resonance decaying to the Xi(-)(b)pi(+) final state is presented. The state, referred to as Xi(b) (6227)(0), has a measured mass and natural width of m(Xi(b)(6227)(0)) = 6227.1(-1.5)(+1.4) +/- 0.5 MeV and Gamma(Xi(b)(6227)(0)) = 18.6(-4.1)(+5.0) +/- 1.4 MeV, where the uncertainties are statistical and systematic. The production rate of the Xi(b)(6227)(0) state relative to that of the Xi(-)(b) baryon in the kinematic region 2 < eta < 5 and p(T) < 30 GeV is measured to be f(Xi b(6227)0)/f(Xi b)(-) B(Xi(b)(6227)(0) -> Xi(-)(b)pi(+)) = 0.045 +/- 0.008 +/- 0.004, where B(Xi(b)(6227)(0) -> Xi(-)(b)pi(+)) is the branching fraction of the decay, and f(Xi b(6227)0) and f(Xi b-) represent fragmentation fractions. Improved measurements of the mass and natural width of the previously observedf Xi(b)(6227)(-) state, along with the mass of the Xi(-)(b) baryon, are also reported. Both measurements are significantly more precise than, and consistent with, previously reported values. |
| Address |
[Leite, J. Baptista; Bediaga, I; Torres, M. Cruz; De Miranda, J. M.; dos Reis, A. C.; Gomes, A.; Massafferri, A.; Machado, D. Torres] Ctr Brasileiro Pesquisas Fis CBPF, Rio De Janeiro, Brazil |
| 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 |
2470-0010 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
WOS:000605120700001 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
4684 |
| Permanent link to this record |
| |
|
| |
| Author |
Linster, M.; Lopez-Pavon, J.; Ziegler, R. |
| Title |
Neutrino observables from a U(2) flavor symmetry |
Type |
Journal Article |
| Year |
2021 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
| Volume |
103 |
Issue |
1 |
Pages |
015020 - 9pp |
| Keywords |
|
| Abstract |
We study the predictions for CP phases and absolute neutrino mass scale for broad classes of models with a U(2)-like flavor symmetry. For this purpose we consider the same special textures in neutrino and charged lepton mass matrices that are successful in the quark sector. While in the neutrino sector the U(2) structure enforces two texture zeros, the contribution of the charged lepton sector to the Pontecorvo-Maki-Nakagawa-Sakata (PMNS) matrix can be parametrized by two rotation angles. Restricting to the cases where at least one of these angles is small, we obtain three representative scenarios. In all scenarios we obtain a narrow prediction for the sum of neutrino masses in the range of 60-75 meV, possibly in the reach of upcoming galaxy survey experiments. All scenarios can be excluded if near-future experimental date provide evidence for either neutrinoless double-beta decay or inverted neutrino mass ordering. |
| Address |
[Linster, Matthias; Ziegler, Robert] Karlsruhe Inst Technol, Inst Theoret Teilchenphys, D-76131 Karlsruhe, Germany |
| 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 |
2470-0010 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
WOS:000609014300006 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
4689 |
| Permanent link to this record |
| |
|
| |
| Author |
ATLAS Collaboration (Aad, G. et al); Aparisi Pozo, J.A.; Bailey, A.J.; Cabrera Urban, S.; Cardillo, F.; Castillo, F.L.; Castillo Gimenez, V.; Costa, M.J.; Escobar, C.; Estrada Pastor, O.; Ferrer, A.; Fiorini, L.; Fullana Torregrosa, E.; Fuster, J.; Garcia, C.; Garcia Navarro, J.E.; Gonzalez de la Hoz, S.; Gonzalvo Rodriguez, G.R.; Guerrero Rojas, J.G.R.; Higon-Rodriguez, E.; Lacasta, C.; Lozano Bahilo, J.J.; Madaffari, D.; Mamuzic, J.; Marti-Garcia, S.; Martinez Agullo, P.; Mitsou, V.A.; Moreno Llacer, M.; Poveda, J.; Prades Ibañez, A.; Rodriguez Bosca, S.; Ruiz-Martinez, A.; Sabatini, P.; Salt, J.; Santra, A.; Sayago Galvan, I.; Soldevila, U.; Sanchez, J.; Torro Pastor, E.; Valero, A.; Valls Ferrer, J.A.; Vos, M. |
| Title |
Search for phenomena beyond the Standard Model in events with large b-jet multiplicity using the ATLAS detector at the LHC |
Type |
Journal Article |
| Year |
2021 |
Publication |
European Physical Journal C |
Abbreviated Journal |
Eur. Phys. J. C |
| Volume |
81 |
Issue |
1 |
Pages |
11 - 29pp |
| Keywords |
|
| Abstract |
A search is presented for new phenomena in events characterised by high jet multiplicity, no leptons (electrons or muons), and four or more jets originating from the fragmentation of b-quarks (b-jets). The search uses 139fb(-1)of s root = 13 TeV proton-proton collision data collected by the ATLAS experiment at the Large Hadron Collider during Run 2. The dominant Standard Model background originates from multijet production and is estimated using a data-driven technique based on an extrapolation from events with low b-jet multiplicity to the high b-jet multiplicities used in the search. No significant excess over the Standard Model expectation is observed and 95% confidence-level limits that constrain simplified models of R-parity-violating supersymmetry are determined. The exclusion limits reach 950 GeV in top-squark mass in the models considered. |
| Address |
[Banerjee, S.; Dang, N. P.; Duvnjak, D.; Jackson, P.; Oliver, J. L.; Petridis, A.; Qureshi, A.; Sharma, A. S.; White, M. J.] Univ Adelaide, Dept Phys, Adelaide, SA, Australia |
| 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:000610446600001 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
4690 |
| Permanent link to this record |
| |
|
| |
| Author |
ATLAS Collaboration (Aaboud, M. et al); Alvarez Piqueras, D.; Aparisi Pozo, J.A.; Bailey, A.J.; Cabrera Urban, S.; Castillo, F.L.; Castillo Gimenez, V.; Cerda Alberich, L.; Costa, M.J.; Escobar, C.; Estrada Pastor, O.; Ferrer, A.; Fiorini, L.; Fullana Torregrosa, E.; Fuster, J.; Garcia, C.; Garcia Navarro, J.E.; Gonzalez de la Hoz, S.; Gonzalvo Rodriguez, G.R.; Guerrero Rojas, J.G.R.; Higon-Rodriguez, E.; Jimenez Pena, J.; Lacasta, C.; Lozano Bahilo, J.J.; Madaffari, D.; Mamuzic, J.; Marti-Garcia, S.; Melini, D.; Miñano, M.; Mitsou, V.A.; Rodriguez Bosca, S.; Rodriguez Rodriguez, D.; Ruiz-Martinez, A.; Salt, J.; Santra, A.; Soldevila, U.; Sanchez, J.; Valero, A.; Valls Ferrer, J.A.; Vos, M. |
| Title |
Measurement of the jet mass in high transverse momentum Z(-> b(b)over-bar)gamma production at root s=13 TeV using the ATLAS detector |
Type |
Journal Article |
| Year |
2021 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
| Volume |
812 |
Issue |
|
Pages |
135991 - 23pp |
| Keywords |
|
| Abstract |
The integrated fiducial cross-section and unfolded differential jet mass spectrum of high transverse momentum Z -> b (b) over bar decays are measured in Z gamma events in proton-proton collisions at root s = 13 TeV. The data analysed were collected between 2015 and 2016 with the ATLAS detector at the Large Hadron Collider and correspond to an integrated luminosity of 36.1 fb(-1). Photons are required to have a transverse momentum p(T) > 175 GeV. The Z -> b (b) over bar decay is reconstructed using a jet with p(T) > 200 GeV, found with the anti-k(t) R = 1.0 jet algorithm, and groomed to remove soft and wide-angle radiation and to mitigate contributions from the underlying event and additional proton-proton collisions. Two different but related measurements are performed using two jet grooming definitions for reconstructing the Z -> b (b) over bar decay: trimming and soft drop. These algorithms differ in their experimental and phenomenological implications regarding jet mass reconstruction and theoretical precision. To identify Zbosons, b-tagged R = 0.2 track-jets matched to the groomed large-R calorimeter jet are used as a proxy for the b-quarks. The signal yield is determined from fits of the data-driven background templates to the different jet mass distributions for the two grooming methods. Integrated fiducial cross-sections and unfolded jet mass spectra for each grooming method are compared with leading-order theoretical predictions. The results are found to be in good agreement with Standard Model expectations within the current statistical and systematic uncertainties. |
| Address |
[Banerjee, S.; Dang, N. P.; Duvnjak, D.; Jackson, P.; Oliver, J. L.; Petridis, A.; Qureshi, A.; Sharma, A. S.; White, M. J.] Univ Adelaide, Dept Phys, Adelaide, SA, Australia |
| Corporate Author |
|
Thesis |
|
| Publisher |
Elsevier |
Place of Publication |
|
Editor |
|
| Language |
English |
Summary Language |
|
Original Title |
|
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0370-2693 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
WOS:000608167600013 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
4691 |
| Permanent link to this record |
| |
|
| |
| Author |
ATLAS Collaboration (Aad, G. et al); Aparisi Pozo, J.A.; Bailey, A.J.; Cabrera Urban, S.; Cardillo, F.; Castillo, F.L.; Castillo Gimenez, V.; Costa, M.J.; Escobar, C.; Estrada Pastor, O.; Ferrer, A.; Fiorini, L.; Fullana Torregrosa, E.; Fuster, J.; Garcia, C.; Garcia Navarro, J.E.; Gonzalez de la Hoz, S.; Gonzalvo Rodriguez, G.R.; Guerrero Rojas, J.G.R.; Higon-Rodriguez, E.; Lacasta, C.; Lozano Bahilo, J.J.; Madaffari, D.; Mamuzic, J.; Marti-Garcia, S.; Martinez Agullo, P.; Mitsou, V.A.; Moreno Llacer, M.; Poveda, J.; Prades Ibañez, A.; Rodriguez Bosca, S.; Ruiz-Martinez, A.; Sabatini, P.; Salt, J.; Santra, A.; Sayago Galvan, I.; Soldevila, U.; Sanchez, J.; Torro Pastor, E.; Valero, A.; Valls Ferrer, J.A.; Vos, M. |
| Title |
A search for the dimuon decay of the Standard Model Higgs boson with the ATLAS detector |
Type |
Journal Article |
| Year |
2021 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
| Volume |
812 |
Issue |
|
Pages |
135980 - 24pp |
| Keywords |
|
| Abstract |
A search for the dimuon decay of the Standard Model (SM) Higgs boson is performed using data corresponding to an integrated luminosity of 139 fb(-1) collected with the ATLAS detector in Run 2 pp collisions at root s = 13 TeV at the Large Hadron Collider. The observed (expected) significance over the background-only hypothesis for a Higgs boson with a mass of 125.09 GeV is 2.0 sigma (1.7 sigma). The observed upper limit on the cross section times branching ratio for pp -> H -> μμis 2.2 times the SM prediction at 95% confidence level, while the expected limit on a H -> μμsignal assuming the absence (presence) of a SM signal is 1.1(2.0). The best-fit value of the signal strength parameter, defined as the ratio of the observed signal yield to the one expected in the SM, is μ= 1.2 +/- 0.6. |
| Address |
[Banerjee, S.; Dang, N. P.; Duvnjak, D.; Jackson, P.; Oliver, J. L.; Petridis, A.; Qureshi, A.; Sharma, A. S.; White, M. J.] Univ Adelaide, Dept Phys, Adelaide, SA, Australia |
| Corporate Author |
|
Thesis |
|
| Publisher |
Elsevier |
Place of Publication |
|
Editor |
|
| Language |
English |
Summary Language |
|
Original Title |
|
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0370-2693 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
WOS:000608167600020 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
4692 |
| Permanent link to this record |
| |
|
| |
| Author |
Bruschini, R.; Gonzalez, P. |
| Title |
Strong decays of the lowest bottomonium hybrid within an extended Born-Oppenheimer framework |
Type |
Journal Article |
| Year |
2021 |
Publication |
European Physical Journal C |
Abbreviated Journal |
Eur. Phys. J. C |
| Volume |
81 |
Issue |
1 |
Pages |
74 - 9pp |
| Keywords |
|
| Abstract |
We analyze the decays of the theoretically predicted lowest bottomonium hybrid H(1P) to open bottom two-meson states. We do it by embedding a quark pair creation model into the Born-Oppenheimer framework which allows for a unified, QCD-motivated description of bottomonium hybrids as well as bottomonium. A new 1P1 decay model for H(1P) comes out. The same analysis applied to bottomonium leads naturally to the well-known 3 P0 decay model. We show that H(1P) and the theoretically predicted bottomonium state Upsilon (5S), whose calculated masses are close to each other, have very different widths for such decays. A comparison with data from Upsilon (10860), an experimental resonance whose mass is similar to that of Upsilon (5S) and H(1P), is carried out. Neither a Upsilon (5S) nor a H(1P) assignment can explain the measured decay widths. However, a Upsilon (5S)-H(1P) mixing may give account of them supporting previous analyses of dipion decays of Upsilon (10860) and suggesting a possible experimental evidence of H(1P). |
| Address |
[Bruschini, R.; Gonzalez, P.] Univ Valencia, CSIC, Inst Fis Corpuscular, Unidad Teor, Valencia 46980, Spain, Email: roberto.bruschini@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:000612840500001 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
no |
| Call Number |
IFIC @ pastor @ |
Serial |
4695 |
| Permanent link to this record |
| |
|
| |
| Author |
Woolley, B.; Burt, G.; Dexter, A.C.; Peacock, R.; Millar, W.L.; Catalan Lasheras, N.; Degiovanni, A.; Grudiev, A.; Mcmonagle, G.; Syratchev, I.; Wuensch, W.; Rodriguez Castro, E.; Giner Navarro, J. |
| Title |
High-gradient behavior of a dipole-mode rf structure |
Type |
Journal Article |
| Year |
2020 |
Publication |
Physical Review Accelerators and Beams |
Abbreviated Journal |
Phys. Rev. Accel. Beams |
| Volume |
23 |
Issue |
12 |
Pages |
122002 - 11pp |
| Keywords |
|
| Abstract |
A normal-conducting, X-band traveling wave structure operating in the dipole mode has been systematically high-gradient tested to gain insight into the maximum possible gradients in these types of structure. Measured structure conditioning, breakdown behavior, and achieved surface fields are reported as well as a postmortem analysis of the breakdown position and a scanning electron microscope analysis of the high-field surfaces. The results of these measurements are then compared to high-gradient results from monopole-mode cavities. Scaled to a breakdown rate of 10(-6), the cavities were found to operate at a peak electric field of 154 MV/m and a peak modified Poynting vector S-c of 5.48 MW/mm(2). The study provides important input for the further development of dipole-mode cavities for use in the Compact Linear Collider as a crab cavity and dipole-mode cavities for use in x-ray free-electron lasers as well as for studies of the fundamental processes in vacuum arcs. Of particular relevance are the unique field patterns in dipole cavities compared to monopole cavities, where the electric and magnetic fields peak in orthogonal planes, which allow the separation of the role of electric and magnetic fields in breakdown via postmortem damage observation. The azimuthal variation of breakdown crater density is measured and is fitted to sinusoidal functions. The best fit is a power law fit of exponent 6. This is significant, as it shows how breakdown probability varies over a surface area with a varying electric field after conditioning to a given peak field. |
| Address |
[Woolley, B.; Burt, G.; Dexter, A. C.; Peacock, R.; Millar, W. L.] Univ Lancaster, Lancaster LA1 4YW, England |
| 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 |
2469-9888 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
WOS:000614886300002 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
4696 |
| Permanent link to this record |
| |
|
| |
| Author |
Antusch, S.; Figueroa, D.G.; Marschall, K.; Torrenti, F. |
| Title |
Energy distribution and equation of state of the early Universe: Matching the end of inflation and the onset of radiation domination |
Type |
Journal Article |
| Year |
2020 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
| Volume |
811 |
Issue |
|
Pages |
135888 - 7pp |
| Keywords |
|
| Abstract |
We study the energy distribution and equation of state of the universe between the end of inflation and the onset of radiation domination (RD), considering observationally consistent single-field inflationary scenarios, with a potential 'flattening' at large field values, and a monomial shape V(phi) proportional to vertical bar phi vertical bar(p) around the origin. As a proxy for (p)reheating, we include a quadratic interaction g(2)phi X-2(2) between the inflaton phi and a light scalar 'daughter' field X, with g(2) > 0. We capture the non-perturbative and non-linear nature of the system dynamics with lattice simulations, obtaining that: i) the final energy transferred to X depends only on p, not on g(2); ii) the final transfer of energy is always negligible for 2 <= p < 4, and of order similar to 50% for p >= 4; iii) the system goes at late times to matter-domination for p = 2, and always to RD for p > 2. In the latter case we calculate the number of e-folds until RD, significantly reducing the uncertainty in the inflationary observables Tl-s and r. |
| Address |
[Antusch, Stefan; Marschall, Kenneth; Torrenti, Francisco] Univ Basel, Dept Phys, Klingelbergstr 82, CH-4056 Basel, Switzerland, Email: f.torrenti@unibas.ch |
| Corporate Author |
|
Thesis |
|
| Publisher |
Elsevier |
Place of Publication |
|
Editor |
|
| Language |
English |
Summary Language |
|
Original Title |
|
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0370-2693 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
WOS:000612225400040 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
4699 |
| Permanent link to this record |
