| |
Records |
Links |
|
Author |
Granero, D.; Perez-Calatayud, J.; Vijande, J.; Ballester, F.; Rivard, M.J. |
|
| |
Title |
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 |
Valcarce, A.; Garcilazo, H.; Vijande, J. |
|
| |
Title |
Heavy baryon spectroscopy with relativistic kinematics |
Type |
Journal Article |
| |
Year |
2014 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
|
| |
Volume |
733 |
Issue |
|
Pages |
288-295 |
|
| |
Keywords |
|
|
| |
Abstract |
We present a comparative Faddeev study of heavy baryon spectroscopy with nonrelativistic and relativistic kinematics. We show results for different standard hyperfine interactions with both kinematics in an attempt to learn about the light quark dynamics. We highlight the properties of particular states accessible in nowadays laboratories that would help in discriminating between different dynamical models. The advance in the knowledge of light quark dynamics is a key tool for the understanding of the existence of exotic hadrons. |
|
| |
Address |
[Valcarce, A.] Univ Salamanca, Dept Fis Fundamental, E-37008 Salamanca, Spain |
|
| |
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:000336430400050 |
Approved |
no |
|
| |
Is ISI |
yes |
International Collaboration |
yes |
|
| |
Call Number |
IFIC @ pastor @ |
Serial |
1806 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Vijande, J.; Valcarce, A.; Carames, T.F.; Richard, J.M. |
|
| |
Title |
Multiquark Systems |
Type |
Journal Article |
| |
Year |
2014 |
Publication |
Few-Body Systems |
Abbreviated Journal |
Few-Body Syst. |
|
| |
Volume |
55 |
Issue |
8-10 |
Pages |
675-681 |
|
| |
Keywords |
|
|
| |
Abstract |
In this talk we tackle the description of hadron spectroscopy in terms of the constituent quark model. We focus on the mesonic charm sector, where several of the new reported resonances seem to defy their classification as simple quark-antiquark states. We pay special attention to higher order Fock space components in describing excited states of the meson spectra in close connection with the hadron-hadron interaction. The main goal of the present study is a coherent understanding of the low-energy hadron phenomenology without enforcing any particular model, to constrain its characteristics and learn about low-energy realization of the theory. |
|
| |
Address |
[Vijande, J.] Univ Valencia, Dept Fis Atom Mol & Nucl, Valencia, Spain, Email: javier.vijande@uv.es |
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
Springer Wien |
Place of Publication |
|
Editor |
|
|
| |
Language |
English |
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0177-7963 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
WOS:000339828900015 |
Approved |
no |
|
| |
Is ISI |
yes |
International Collaboration |
yes |
|
| |
Call Number |
IFIC @ pastor @ |
Serial |
1864 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Pujades, M.C.; Granero, D.; Vijande, J.; Ballester, F.; Perez-Calatayud, J.; Papagiannis, P.; Siebert, F.A. |
|
| |
Title |
Air-kerma evaluation at the maze entrance of HDR brachytherapy facilities |
Type |
Journal Article |
| |
Year |
2014 |
Publication |
Journal of Radiological Protection |
Abbreviated Journal |
J. Radiol. Prot. |
|
| |
Volume |
34 |
Issue |
4 |
Pages |
741-753 |
|
| |
Keywords |
bunker; shielding; NCRP 151; brachytherapy; Monte Carlo |
|
| |
Abstract |
In the absence of procedures for evaluating the design of brachytherapy (BT) facilities for radiation protection purposes, the methodology used for external beam radiotherapy facilities is often adapted. The purpose of this study is to adapt the NCRP 151 methodology for estimating the air-kerma rate at the door in BT facilities. Such methodology was checked against Monte Carlo (MC) techniques using the code Geant4. Five different facility designs were studied for Ir-192 and Co-60 HDR applications to account for several different bunker layouts. For the estimation of the lead thickness needed at the door, the use of transmission data for the real spectra at the door instead of the ones emitted by Ir-192 and Co-60 will reduce the lead thickness by a factor of five for Ir-192 and ten for Co-60. This will significantly lighten the door and hence simplify construction and operating requirements for all bunkers. The adaptation proposed in this study to estimate the air-kerma rate at the door depends on the complexity of the maze: it provides good results for bunkers with a maze (i.e. similar to those used for linacs for which the NCRP 151 methodology was developed) but fails for less conventional designs. For those facilities, a specific Monte Carlo study is in order for reasons of safety and cost-effectiveness. |
|
| |
Address |
[Pujades, M. C.] Natl Ctr Dosimetry CND, Valencia, Spain, Email: mpuclau@gmail.com |
|
| |
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 |
0952-4746 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
WOS:000345895800005 |
Approved |
no |
|
| |
Is ISI |
yes |
International Collaboration |
yes |
|
| |
Call Number |
IFIC @ pastor @ |
Serial |
2031 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Vijande, J.; Valcarce, A.; Garcilazo, H. |
|
| |
Title |
Constituent-quark model description of triply heavy baryon nonperturbative lattice QCD data |
Type |
Journal Article |
| |
Year |
2015 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
|
| |
Volume |
91 |
Issue |
5 |
Pages |
054011 - 7pp |
|
| |
Keywords |
|
|
| |
Abstract |
This paper provides results for the spectra of triply charmed and bottom baryons based on a constituent-quark model approach. We take advantage of the assumption that potential models are expected to describe triply heavy baryons to a similar degree of accuracy as the successful results obtained in the charmonium and bottomonium sectors. The high precision calculation of the ground state and positive and negative parity excited states recently reported by nonperturbative lattice QCD provides us with a unique opportunity to confront model predictions with the data. This comparison may also help to build a bridge between two difficult to reconcile lattice QCD results, namely, the lattice SU(3) QCD static three-quark potential and the recent results of nonperturbative lattice QCD for the triply heavy baryon spectra. |
|
| |
Address |
[Vijande, J.] Univ Valencia, Dept Fis Atom Mol & Nucl, E-46100 Burjassot, 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:000352025200005 |
Approved |
no |
|
| |
Is ISI |
yes |
International Collaboration |
yes |
|
| |
Call Number |
IFIC @ pastor @ |
Serial |
2184 |
|
| Permanent link to this record |
