RECORD
Quantitative Predictions for $B$ semileptonic decays into $D,D^*$ and the orbitally excited $D^{**}$ in quark models \`a la Bakamjian-Thomas
High Energy Physics - Phenomenology · Submitted 5 Jun 1997
abstract compiled · 2026-09-23 · no language-model review
The authors' main claim The overall agreement with experiment is rather good within the present accuracy which is poor for the orbitally excited charmed mesons.
The compiled record
The paper's own sentences, arranged. Each label is drawn from a closed vocabulary; the number beside it is the probability the classifier gave that label. Numbers in the tables are the authors', checked by code. No sentence in this record was written by a model.
Open the compiled record
The abstract, sentence by sentence
Once chosen the dynamics in one frame, the rest frame in this paper, the Bakamjian and Thomas method allows to define relativistic quark models in any frame. These models have been shown to provide, in the infinite quark mass limit, fully covariant current form factors as matrix elements of the quark current operator. In this paper we use the rest frame dynamics fitted from the meson spectrum by various authors, already shown to provide a reasonable value for $\rho^2$. From the general formulae for the scaling invariant form factors $\xi^{(n)}(w)$, $\tau_{1/2}^{(n)}(w)$ and $\tau_{3/2}^{(n)}(w)$, we predict quantitavely the $B$ semileptonic branching ratios to the ground state and orbitally excited charmed mesons $D, D^\ast$ and $D^{\ast\ast}$. We check Bjorken's sum rule and discuss the respective contributions to it. We find $\xi(w)\simeq (2/(1+w)) ^2$, resulting from the fact that the ground state wave function is Coulomb-like. We also find $\tau_{3/2}\simeq 0.5 (2/(1+w))^3$ and $\tau_{1/2}(w)\ll \tau_{3/2}(w)$. Very small branching ratios into $j=1/2$ orbitally excited $D$'s results. The overall agreement with experiment is rather good within the present accuracy which is poor for the orbitally excited charmed mesons. We predict a ratio $Br(B\to D^\ast_2 l \nu)/Br(B\to D_1 l \nu)=1.55\pm 0.15$ as a mere consequence of the heavy quark symmetry. If some faint experimental indications that $Br(B\to D_1 l \nu)\simeq Br(B\to D^\ast_2 l \nu)$ were confirmed, it would indicate a sizeable $O(1/m_c)$ correction.
background contribution method result interpretation main claim
| # | sentence | role | the authors' own work | states the main conclusion | strength |
|---|---|---|---|---|---|
| s0 | Once chosen the dynamics in one frame, the rest frame in this paper, the Bakamjian and Thomas method allows to define relativistic quark models in any frame. | method 0.54 | 0.14 | 0.03 | asserted 1.00 |
| s1 | These models have been shown to provide, in the infinite quark mass limit, fully covariant current form factors as matrix elements of the quark current operator. | background 0.96 | 0.09 | 0.03 | asserted 1.00 |
| s2 | In this paper we use the rest frame dynamics fitted from the meson spectrum by various authors, already shown to provide a reasonable value for $\rho^2$. | method 0.95 | 0.34 | 0.03 | asserted 0.92 |
| s3 | From the general formulae for the scaling invariant form factors $\xi^{(n)}(w)$, $\tau_{1/2}^{(n)}(w)$ and $\tau_{3/2}^{(n)}(w)$, we predict quantitavely the $B$ semileptonic branching ratios to the ground state and orbitally excited charmed mesons $D, D^\ast$ and $D^{\ast\ast}$. | contribution 0.96 | 0.92 | 0.31 | asserted 1.00 |
| s4 | We check Bjorken's sum rule and discuss the respective contributions to it. | contribution 0.87 | 0.89 | 0.04 | asserted 0.82 |
| s5 | We find $\xi(w)\simeq (2/(1+w)) ^2$, resulting from the fact that the ground state wave function is Coulomb-like. | result 0.99 | 0.94 | 0.13 | asserted 1.00 |
| s6 | We also find $\tau_{3/2}\simeq 0.5 (2/(1+w))^3$ and $\tau_{1/2}(w)\ll \tau_{3/2}(w)$. | result 1.00 | 0.96 | 0.12 | asserted 1.00 |
| s7 | Very small branching ratios into $j=1/2$ orbitally excited $D$'s results. | result 1.00 | 0.90 | 0.09 | asserted 1.00 |
| s8 | The overall agreement with experiment is rather good within the present accuracy which is poor for the orbitally excited charmed mesons. | interpretation 0.47 | 0.81 | 0.23 | asserted 0.92 |
| s9 | We predict a ratio $Br(B\to D^\ast_2 l \nu)/Br(B\to D_1 l \nu)=1.55\pm 0.15$ as a mere consequence of the heavy quark symmetry. | result 1.00 | 0.91 | 0.22 | asserted 1.00 |
| s10 | If some faint experimental indications that $Br(B\to D_1 l \nu)\simeq Br(B\to D^\ast_2 l \nu)$ were confirmed, it would indicate a sizeable $O(1/m_c)$ correction. | interpretation 0.98 | 0.20 | 0.07 | hedged possibility 0.93 |
What was examined, and what was not
- arXiv listing abstract v2
- full text
- figures and tables
- references and citing sentences
- relations to other papers
- P abstract
- S sections
- T body sentences
- C citations
- R cross-paper relations
The paper
Original abstract
Once chosen the dynamics in one frame, the rest frame in this paper, the Bakamjian and Thomas method allows to define relativistic quark models in any frame. These models have been shown to provide, in the infinite quark mass limit, fully covariant current form factors as matrix elements of the quark current operator. In this paper we use the rest frame dynamics fitted from the meson spectrum by various authors, already shown to provide a reasonable value for $\rho^2$. From the general formulae for the scaling invariant form factors $\xi^{(n)}(w)$, $\tau_{1/2}^{(n)}(w)$ and $\tau_{3/2}^{(n)}(w)$, we predict quantitavely the $B$ semileptonic branching ratios to the ground state and orbitally excited charmed mesons $D, D^\ast$ and $D^{\ast\ast}$. We check Bjorken's sum rule and discuss the respective contributions to it. We find $\xi(w)\simeq (2/(1+w)) ^2$, resulting from the fact that the ground state wave function is Coulomb-like. We also find $\tau_{3/2}\simeq 0.5 (2/(1+w))^3$ and $\tau_{1/2}(w)\ll \tau_{3/2}(w)$. Very small branching ratios into $j=1/2$ orbitally excited $D$'s results. The overall agreement with experiment is rather good within the present accuracy which is poor for the orbitally excited charmed mesons. We predict a ratio $Br(B\to D^\ast_2 l \nu)/Br(B\to D_1 l \nu)=1.55\pm 0.15$ as a mere consequence of the heavy quark symmetry. If some faint experimental indications that $Br(B\to D_1 l \nu)\simeq Br(B\to D^\ast_2 l \nu)$ were confirmed, it would indicate a sizeable $O(1/m_c)$ correction.
Human review
References
How the literature uses it
11 arXiv papers cite this in 13 sentences
Papers citing it · 8 sentences without a confident label
Compares with it 2 papers
-
One observes that for reasonable intervals of masses[Constituent mass of quarks in the presented model is smaller than in other similar quark models due to the explicit inclusion of gluon condensate in the dynamics of the model.] slope is of the order of -1 and beyond, which is in agreement with values mentioned in the Introduction, as well as with values obtained within other theoretical frameworks [ref] and on the lattice [ref] .
The Isgur-Wise Function within a Modified Heavy-Light Chiral Quark Model · Results and discussion · 0.84
-
Our result ([ref]) is also similar to the prediction of a Bakamjian-Thomas relativistic quark model [ref] , when using a Godfrey-Isgur interquark potential: $τ_1/2 = 0.22$ and $τ_3/2 = 0.54$.
Lattice calculation of the Isgur-Wise functions tau_{1/2} and tau_{3/2} with dynamical quarks · Conclusions · 0.99
Cites it as background 3 papers
-
The significant discrepancies in the theories and experiments have been discussed in several works [ref] .
A proposal to the '$\frac{1}{2}$ vs. $\frac{3}{2}$ puzzle' · Introduction · 0.89
-
Another related issue is the long-standing so-called “$1/2$ vs. $3/2$” puzzle in semileptonic $B$ decays [ref] .
-
The theoretical argument relies on a series of sum rules [ref] derived from QCD comforted by model calculations [ref] .
Lattice calculation of the Isgur-Wise functions tau_{1/2} and tau_{3/2} with dynamical quarks · Introduction · 0.80
Discussion
Know something about this paper? Leave a comment, or highlight any passage above to comment on it.