|
Records |
Links |
|
Author |
Navarro-Salas, J.; Pla, S. |
|
|
Title |
(F, G)-summed form of the QED effective action |
Type |
Journal Article |
|
Year |
2021 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
|
|
Volume |
103 |
Issue |
8 |
Pages |
L081702 - 7pp |
|
|
Keywords |
|
|
|
Abstract |
We conjecture that the proper-time series expansion of the one-loop effective Lagrangian of quantum electrodynamics can be summed in all terms containing the field-strength invariants F = 1/4F F-mu nu(mu nu) (x), G = 1/4 (F) over tilde F-mu nu(mu nu) (x), including those also possessing derivatives of the electromagnetic field strength. This partial resummation is exactly encapsulated in a factor with the same form as the Heisenberg-Euler Lagrangian density, except that now the electric and magnetic fields can depend arbitrarily on spacetime coordinates. We provide strong evidence for this conjecture, which is proved to sixth order in the proper time. Furthermore, and as a byproduct, we generate some solvable electromagnetic backgrounds. We also discuss the implications for a generalization of the Schwinger formula for pair production induced by nonconstant electric fields. Finally, we briefly outline the extension of these results in the presence of gravity. |
|
|
Address |
[Navarro-Salas, Jose; Pla, Silvia] Univ Valencia, Dept Fis Teor, Valencia 46100, Spain, Email: jnavarro@ific.uv.es; |
|
|
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:000649081100005 |
Approved |
no |
|
|
Is ISI |
yes |
International Collaboration |
no |
|
|
Call Number |
IFIC @ pastor @ |
Serial |
4834 |
|
Permanent link to this record |
|
|
|
|
Author |
Aiola, S.; Bandiera, L.; Cavoto, G.; De Benedetti, F.; Fu, J.; Guidi, V.; Henry, L.; Marangotto, D.; Martinez-Vidal, F.; Mascagna, V.; Mazorra de Cos, J.; Mazzolari, A.; Merli, A.; Neri, N.; Prest, M.; Romagnoni, M.; Ruiz Vidal, J.; Soldani, M.; Sytov, A.; Tikhomirov, V.; Vallazza, E. |
|
|
Title |
Progress towards the first measurement of charm baryon dipole moments |
Type |
Journal Article |
|
Year |
2021 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
|
|
Volume |
103 |
Issue |
7 |
Pages |
072003 - 15pp |
|
|
Keywords |
|
|
|
Abstract |
Electromagnetic dipole moments of short-lived particles are sensitive to physics within and beyond the Standard Model of particle physics but have not been accessible experimentally to date. To perform such measurements it has been proposed to exploit the spin precession of channeled particles in bent crystals at the LHC. Progress that enables the first measurement of charm baryon dipole moments is reported. In particular, the design and characterization on beam of silicon and germanium bent crystal prototypes, the optimization of the experimental setup, and advanced analysis techniques are discussed. Sensitivity studies show that first measurements of Lambda(+)(c) and Xi(+)(c) baryon dipole moments can he performed in two years of data taking with an experimental setup positioned upstream of the LHCb detector. |
|
|
Address |
[Aiola, S.; De Benedetti, F.; Fu, J.; Henry, L.; Marangotto, D.; Merli, A.; Neri, N.] Ist Nazl Fis Nucl, Sez Milano, Milan, Italy |
|
|
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:000648575400001 |
Approved |
no |
|
|
Is ISI |
yes |
International Collaboration |
yes |
|
|
Call Number |
IFIC @ pastor @ |
Serial |
4835 |
|
Permanent link to this record |
|
|
|
|
Author |
Richard, J.M.; Valcarce, A.; Vijande, J. |
|
|
Title |
Effect of relativistic kinematics on the stability of multiquarks |
Type |
Journal Article |
|
Year |
2021 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
|
|
Volume |
103 |
Issue |
5 |
Pages |
054020 - 8pp |
|
|
Keywords |
|
|
|
Abstract |
We discuss whether the bound nature of multiquark states in quark models could benefit from relativistic effects on the kinetic energy operator. For mesons and baryons, relativistic corrections to the kinetic energy lead to lower energies, and thus call for a retuning of the parameters of the model. For multiquark states, as well as their respective thresholds, a comparison is made of the results obtained with nonrelativistic and relativistic kinetic energy. It is found that the binding energy is lower in the relativistic case. In particular, QQ (q) over bar(q) over bar tetraquarks with double heavy flavor become stable for a larger ratio of the heavy to light quark masses; the all-heavy tetraquarks QQ (Q) over bar(Q) over bar that are not stable in standard nonrelativistic quark models remain unstable when a relativistic form of kinetic energy is adopted. |
|
|
Address |
[Richard, Jean-Marc] Univ Lyon, Inst Phys Infinis Lyon 2, IN2P3 CNRS UCBL, 4 Rue Enrico Fermi, F-69622 Villeurbanne, France, Email: j-m.richard@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 |
2470-0010 |
ISBN |
|
Medium |
|
|
|
Area |
|
Expedition |
|
Conference |
|
|
|
Notes |
WOS:000648531300004 |
Approved |
no |
|
|
Is ISI |
yes |
International Collaboration |
yes |
|
|
Call Number |
IFIC @ pastor @ |
Serial |
4838 |
|
Permanent link to this record |
|
|
|
|
Author |
Brunet, M. et al; Nacher, E. |
|
|
Title |
Competition between allowed and first-forbidden beta decays of At-208 and expansion of the Po-208 level scheme |
Type |
Journal Article |
|
Year |
2021 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
|
|
Volume |
103 |
Issue |
5 |
Pages |
054327 - 13pp |
|
|
Keywords |
|
|
|
Abstract |
The structure of Po-208 populated through the EC/beta(+) decay of At-208 is investigated using gamma-ray spectroscopy at the ISOLDE Decay Station. The presented level scheme contains 27 new excited states and 43 new transitions, as well as a further 50 previously observed. rays which have been (re)assigned a position. The level scheme is compared to shell model calculations. Through this analysis approximately half of the beta-decay strength of At-208 is found to proceed via allowed decay and half via first-forbidden decay. The first-forbidden transitions predominantly populate core excited states at high excitation energies, which is qualitatively understood using shell model considerations. This mass region provides an excellent testing ground for the competition between allowed and first-forbidden beta-decay calculations, important for the detailed understanding of the nucleosynthesis of heavy elements. |
|
|
Address |
[Brunet, M.; Podolyak, Zs; Berry, T. A.; Carroll, R. J.; Regan, P. H.; Rudigier, M.; Shand, C. M.; Shearman, R.] Univ Surrey, Dept Phys, Guildford GU2 7XH, Surrey, England, Email: m.h.brunet@surrey.ac.uk |
|
|
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 |
2469-9985 |
ISBN |
|
Medium |
|
|
|
Area |
|
Expedition |
|
Conference |
|
|
|
Notes |
WOS:000655863700002 |
Approved |
no |
|
|
Is ISI |
yes |
International Collaboration |
yes |
|
|
Call Number |
IFIC @ pastor @ |
Serial |
4839 |
|
Permanent link to this record |
|
|
|
|
Author |
Pla, S.; Newsome, I.M.; Link, R.S.; Anderson, P.R.; Navarro-Salas, J. |
|
|
Title |
Pair production due to an electric field in 1+1 dimensions and the validity of the semiclassical approximation |
Type |
Journal Article |
|
Year |
2021 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
|
|
Volume |
103 |
Issue |
10 |
Pages |
105003 - 23pp |
|
|
Keywords |
|
|
|
Abstract |
Solutions to the backreaction equation in 1 + 1-dimensional semiclassical electrodynamics are obtained and analyzed when considering a time-varying homogeneous electric field initially generated by a classical electric current, coupled to either a quantized scalar field or a quantized spin-1/2 field. Particle production by way of the Schwinger effect leads to backreaction effects that modulate the electric field strength. Details of the particle production process are investigated along with the transfer of energy between the electric field and the particles. The validity of the semiclassical approximation is also investigated using a criterion previously implemented for chaotic inflation and, in an earlier form, semiclassical gravity. The criterion states that the semiclassical approximation will break down if any linearized gauge-invariant quantity constructed from solutions to the linear response equation, with finite nonsingular data, grows rapidly for some period of time. Approximations to homogeneous solutions of the linear response equation are computed and it is found that the criterion is violated when the maximum value, E-max, obtained by the electric field is of the order of the critical scale for the Schwinger effect, E-max similar to E-crit m(2)/q, where m is the mass of the quantized field and q is its electric charge. For these approximate solutions the criterion appears to be satisfied in the extreme limits qE(max)/m(2) << 1 and qE(max)/m(2) >> 1. |
|
|
Address |
[Pla, Silvia; Navarro-Salas, Jose] Univ Valencia, Ctr Mixto Univ Valencia, Fac Fis, CSIC,Dept Fis Teor, E-46100 Valencia, Spain, Email: silvia.pla@uv.es; |
|
|
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:000655874700008 |
Approved |
no |
|
|
Is ISI |
yes |
International Collaboration |
yes |
|
|
Call Number |
IFIC @ pastor @ |
Serial |
4844 |
|
Permanent link to this record |