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Author Granero, D.; Perez-Calatayud, J.; Vijande, J.; Ballester, F.; Rivard, M.J.
Title (up) Limitations of the TG-43 formalism for skin high-dose-rate brachytherapy dose calculations Type Journal Article
Year 2014 Publication Medical Physics Abbreviated Journal Med. Phys.
Volume 41 Issue 2 Pages 021703 - 8pp
Keywords HDR; brachytherapy; skin; Monte Carlo; Geant4; Co-60; Ir-192; Yb-169
Abstract Purpose: In skin high-dose-rate (HDR) brachytherapy, sources are located outside, in contact with, or implanted at some depth below the skin surface. Most treatment planning systems use the TG-43 formalism, which is based on single-source dose superposition within an infinite water medium without accounting for the true geometry in which conditions for scattered radiation are altered by the presence of air. The purpose of this study is to evaluate the dosimetric limitations of the TG-43 formalism in HDR skin brachytherapy and the potential clinical impact. Methods: Dose rate distributions of typical configurations used in skin brachytherapy were obtained: a 5 cm x 5 cm superficial mould; a source inside a catheter located at the skin surface with and without backscatter bolus; and a typical interstitial implant consisting of an HDR source in a catheter located at a depth of 0.5 cm. Commercially available HDR Co-60 and Ir-192 sources and a hypothetical Yb-169 source were considered. The Geant4Monte Carlo radiation transport code was used to estimate dose rate distributions for the configurations considered. These results were then compared to those obtained with the TG-43 dose calculation formalism. In particular, the influence of adding bolus material over the implant was studied. Results: For a 5 cm x 5 cm Ir-192 superficial mould and 0.5 cm prescription depth, dose differences in comparison to the TG-43 method were about -3%. When the source was positioned at the skin surface, dose differences were smaller than -1% for Co-60 and Ir-192, yet -3% for Yb-169. For the interstitial implant, dose differences at the skin surface were -7% for Co-60, -0.6% for Ir-192, and -2.5% for Yb-169. Conclusions: This study indicates the following: (i) for the superficial mould, no bolus is needed; (ii) when the source is in contact with the skin surface, no bolus is needed for either Co-60 and Ir-192. For lower energy radionuclides like Yb-169, bolus may be needed; and (iii) for the interstitial case, at least a 0.1 cm bolus is advised for Co-60 to avoid underdosing superficial target layers. For Ir-192 and Yb-169, no bolus is needed. For those cases where no bolus is needed, its use might be detrimental as the lack of radiation scatter may be beneficial to the patient, although the 2% tolerance for dose calculation accuracy recommended in the AAPM TG-56 report is not fulfilled.
Address [Granero, Domingo] Hosp Gen Univ, ERESA, Dept Radiat Phys, Valencia 46014, Spain, Email: dgranero@eresa.com
Corporate Author Thesis
Publisher Amer Assoc Physicists Medicine Amer Inst Physics Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0094-2405 ISBN Medium
Area Expedition Conference
Notes WOS:000331213300006 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1704
Permanent link to this record
 
 
Author Pastore, A.; Martini, M.; Davesne, D.; Navarro, J.; Goriely, S.; Chamel, N.
Title (up) Linear response theory and neutrino mean free path using Brussels-Montreal Skyrme functionals Type Journal Article
Year 2014 Publication Physical Review C Abbreviated Journal Phys. Rev. C
Volume 90 Issue 2 Pages 025804 - 11pp
Keywords
Abstract The Brussels-Montreal Skyrme functionals have been successful in describing properties of both finite nuclei and infinite homogeneous nuclear matter. In their latest version, these functionals have been equipped with two extra density-dependent terms in order to reproduce simultaneously ground state properties of nuclei and infinite nuclear matter properties while avoiding at the same time the arising of ferromagnetic instabilities. In the present article, we extend our previous results of the linear response theory to include such extra terms at both zero and finite temperature in pure neutron matter. The resulting formalism is then applied to derive the neutrino mean free path. The predictions from the Brussels-Montreal Skyrme functionals are compared with ab initio methods.
Address [Pastore, A.; Martini, M.; Goriely, S.; Chamel, N.] Univ Libre Brussels, Inst Astron & Astrophys, B-1050 Brussels, Belgium
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 0556-2813 ISBN Medium
Area Expedition Conference
Notes WOS:000341027800009 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1901
Permanent link to this record
 
 
Author Davesne, D.; Pastore, A.; Navarro, J.
Title (up) Linear response theory in asymmetric nuclear matter for Skyrme functionals including spin-orbit and tensor terms Type Journal Article
Year 2014 Publication Physical Review C Abbreviated Journal Phys. Rev. C
Volume 89 Issue 4 Pages 044302 - 14pp
Keywords
Abstract The formalism of linear response theory for a Skyrme functional including spin-orbit and tensor terms is generalized to the case of infinite nuclear matter with arbitrary isospin asymmetry. Response functions are obtained by solving an algebraic system of equations, which is explicitly given. Spin-isospin strength functions are analyzed varying the conditions of density, momentum transfer, asymmetry, and temperature. The presence of instabilities, including the spinodal one, is studied by means of the static susceptibility.
Address [Davesne, D.] Univ Lyon, F-69003 Lyon, France, Email: davesne@ipnl.in2p3.fr
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 0556-2813 ISBN Medium
Area Expedition Conference
Notes WOS:000334296000003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1758
Permanent link to this record
 
 
Author Pallis, C.
Title (up) Linking Starobinsky-type inflation in no-scale supergravity to MSSM Type Journal Article
Year 2014 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 04 Issue 4 Pages 024 - 31pp
Keywords particle physics – cosmology connection; supersymmetry and cosmology; cosmology of theories beyond the SM; inflation
Abstract A novel realization of the Starobinsky inflationary model within a moderate extension of the Minimal Supersymmetric Standard Model (MSSM) is presented. The proposed superpotential is uniquely determined by applying a continuous R and a Z2 discrete symmetry, whereas the Kahler potential is associated with a no-scale-type SU(54, 1)/ SU(54) x U(1) R X Z2 Kahler manifold. The inflaton is identified with a Higgs-like modulus whose the vacuum expectation value controls the gravitational strength. Thanks to a strong enough coupling (with a parameter CT involved) between the inflaton and the Ricci scalar curvature, inflation can be attained even for subplanckian values of the inflaton with CT >= 76 and the corresponding effective theory being valid up to the Planck scale. The inflationary observables turn out to be in agreement with the current data and the inflaton mass is predicted to be 3 10(3) GeV. At the cost of a relatively small superpotential coupling constant, the model offers also a resolution of the f,t problem of MSSM for CT <= 4500 and gravitino heavier than about 10(4) GeV. Supplementing MSSM by three right-handed neutrinos we show that spontaneously arising couplings between the inflaton and the particle content of MSSM not only ensure a sufficiently low reheating temperature but also support a scenario of non-thermal leptogenesis consistently with the neutrino oscillation parameters.
Address [Pallis, C.] Univ Valencia, CSIC, Dept Fis Teor, E-46100 Burjassot, Spain, Email: kpallis@auth.gr
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 1475-7516 ISBN Medium
Area Expedition Conference
Notes WOS:000343042800006 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 1961
Permanent link to this record
 
 
Author Makarenko, A.N.; Odintsov, S.D.; Olmo, G.J.
Title (up) Little Rip, Lambda CDM and singular dark energy cosmology from Born-Infeld-f(R) gravity Type Journal Article
Year 2014 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 734 Issue Pages 36-40
Keywords
Abstract We study late-time cosmic accelerating dynamics from Born-Infeld-f(R) gravity in a simplified conformal approach. We find that a variety of cosmic effects such as Little Rip, Lambda CDM universe and dark energy cosmology with finite time future singularities may occur. Unlike the convenient Born-Infeld gravity where in the absence of matter only de Sitter expansion may emerge, apparently any FRW cosmology may be reconstructed from this conformal version of the Born-Infeld-f(R) theory. Despite the fact that the explicit form of f(R) is fixed by the conformal ansatz, the relation between the two metrics in this approach may be changed so as to bring out any desired FRW cosmology.
Address [Makarenko, Andrey N.] Tomsk State Pedag Univ, Tomsk 634061, Russia
Corporate Author Thesis
Publisher Elsevier Science Bv 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:000338943900008 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1861
Permanent link to this record
 
 
Author Herrera-Aguilar, A.; Rojas, A.D.; Santos, E.
Title (up) Localization of gauge fields in a tachyonic de Sitter thick braneworld Type Journal Article
Year 2014 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 74 Issue 4 Pages 2770 - 6pp
Keywords
Abstract In this work we show that universal gauge vector fields can be localized on the recently proposed 5D thick tachyonic braneworld which involves a de Sitter cosmological background induced on the 3-brane. Namely, by performing a suitable decomposition of the vector field, the resulting 4D effective action corresponds to a massive gauge field, while the profile along the extra dimension obeys a Schrodinger-like equation with a Poschl-Teller potential. It turns out that the massless zero mode of the gauge field is bound to the expanding 3-brane and allows us to recover the standard 4D electromagnetic phenomena of our world. Moreover, this zero mode is separated from the continuum of Kaluza-Klein (KK) modes by a mass gap determined by the scale of the expansion parameter. We also were able to analytically solve the corresponding Schrodinger-like equation for arbitrary mass, showing that KK massive modes asymptotically behave like plane waves, as expected.
Address [Herrera-Aguilar, Alfredo; Rojas, Alma D.; Santos, Eli] Univ Autonoma Chiapas, Mesoamer Ctr Theoret Phys, Tuxtla Gutierrez 29050, Chiapas, Mexico, Email: aherreraaguilar@mctp.mx;
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:000334449800001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1751
Permanent link to this record
 
 
Author Ilisie, V.; Pich, A.
Title (up) Low-mass fermiophobic charged Higgs phenomenology in two-Higgs-doublet models Type Journal Article
Year 2014 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 09 Issue 9 Pages 089 - 32pp
Keywords Higgs Physics; Beyond Standard Model
Abstract After the recent discovery of a Higgs-like boson, the possibility of an enlarged scalar sector arises as a natural question. Experimental searches for charged scalars have been already performed with negative results. We analyze the phenomenology associated with a fermiophobic charged Higgs (it does not couple to fermions at tree level), in two-Higgs-doublet models. All present experimental bounds are evaded trivially in this case, and one needs to consider other decay and production channels. We study the associated production of a charged Higgs with either a W or a neutral scalar boson, and the relevant decays for a light fermiophobic charged Higgs. The interesting features of this scenario should result encouraging for the LHC collaborations to perform searches for such a particle.
Address [Ilisie, Victor; Pich, Antonio] Univ Valencia, CSIC, IFIC, E-46071 Valencia, Spain, Email: ilisiev@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 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000342430800001 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 1953
Permanent link to this record
 
 
Author Ullan, M.; Benitez, V.; Quirion, D.; Zabala, M.; Pellegrini, G.; Lozano, M.; Lacasta, C.; Soldevila, U.; Garcia, C.; Fadeyev, V.; Wortman, J.; DeFilippis, J.; Shumko, M.; Grillo, A.A.; Sadrozinski, H.F.W.
Title (up) Low-resistance strip sensors for beam-loss event protection Type Journal Article
Year 2014 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A
Volume 765 Issue Pages 252-257
Keywords Silicon radiation detectors; Strip sensors; Punch through protection; Beam loss; HL-LHC; ATLAS Upgrade
Abstract AC coupled silicon strip sensors can be damaged in case of a beam loss due to the possibility of a large charge accumulation in the bulk, developing very high voltages across the coupling capacitors which can destroy them. Punch-through structures are currently used to avoid this problem helping to evacuate the accumulated charge as large voltages are developing. Nevertheless, previous experiments, performed with laser pulses, have shown that these structures can become ineffective in relatively long strips. The large value of the implant resistance can effectively isolate the “far” end of the strip from the punchthrough structure leading to large voltages. We present here our developments to fabricate lowresistance strip sensors to avoid this problem. The deposition of a conducting material in contact with the implants drastically reduces the strip resistance, assuring the effectiveness of the punch-through structures. First devices have been fabricated with this new technology. Initial results with laser tests show the expected reduction in peak voltages on the low resistivity implants. Other aspects of the sensor performance, including the signal formation, are not affected by the new technology.
Address [Ullan, M.; Benitez, V.; Quirion, D.; Zabala, M.; Pellegrini, G.; Lozano, M.] CSIC, Ctr Nacl Microelect IMB CNM, Barcelona 08193, Spain, Email: Miguel.Ullan@imb-cnm.csic.es
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0168-9002 ISBN Medium
Area Expedition Conference
Notes WOS:000344621000048 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2003
Permanent link to this record
 
 
Author Hernandez, P.; Kekic, M.; Lopez-Pavon, J.
Title (up) Low-scale seesaw models versus N-eff Type Journal Article
Year 2014 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 89 Issue 7 Pages 073009 - 7pp
Keywords
Abstract We consider the contribution of the extra sterile states in generic low-scale seesaw models to extra radiation, parametrized by N-eff. We find that the value of Neff is roughly independent of the seesaw scale within a wide range. We explore the full parameter space in the case of two extra sterile states and find that these models are strongly constrained by cosmological data for any value of the seesaw scale below O(100 MeV).
Address [Hernandez, P.; Kekic, M.] IFIC CSIC UVEG, E-46071 Valencia, Spain
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 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000334317200005 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1754
Permanent link to this record
 
 
Author Racker, J.
Title (up) Mass bounds for baryogenesis from particle decays and the inert doublet model Type Journal Article
Year 2014 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 03 Issue 3 Pages 025 - 23pp
Keywords leptogenesis; baryon asymmetry
Abstract In models for thermal baryogenesis from particle decays, the mass of the decaying particle is typically many orders of magnitude above the TeV scale. We will discuss different ways to lower the energy scale of baryogenesis and present the corresponding lower bounds on the particle's mass. This is done specifically for the inert doublet model with heavy Majorana neutrinos and then we indicate how to extrapolate the results to other scenarios. We also revisit the question of whether or not dark matter, neutrino masses, and the cosmic baryon asymmetry can be explained simultaneously at low energies in the inert doublet model.
Address Univ Valencia, CSIC, Inst Fis Corpuscular IFIC, Valencia 46071, Spain, Email: racker@ific.uv.es
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1475-7516 ISBN Medium
Area Expedition Conference
Notes WOS:000333667900025 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 1744
Permanent link to this record