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Jonathan L. Rosner

Publications and source records attributed to Jonathan L. Rosner.

At least 55 records · Page 3Linked to original sources
arXiv2015

Prospects for observing the lowest-lying odd-parity $Σ_c$ and $Σ_b$ baryons

There exist candidates for the negative-parity states $Λ_{c,b}(1/2^-, 3/2^-)$ consisting of an isospin-zero, spin-zero light diquark $[ud]$ with one unit of orbital angular momentum with respect to a $c,b$ quark. However, there exists only one candidate for the orbital excitations of the $Σ_c(1/2^+)$ and $Σ_c^*(3/2^+)$, and none for the orbital excitations of $Σ_b(1/2^+)$ or $Σ_b^*(3/2^+)$. We extend a previous discussion of odd-parity $Λ_{c,b}$ states and explore some patterns of the odd-parity $Σ_{c,b}$ baryons consisting of a light isospin-one nonstrange diquark $(uu,ud,dd)$ in a state of $L=1$ with respect to the spin-1/2 heavy quark $(c,b)$.

hep-ph↗
arXiv2015

New Exotic Meson and Baryon Resonances from Doubly-Heavy Hadronic Molecules

We predict several new exotic doubly-heavy hadronic resonances, inferring from the observed exotic bottomonium-like and charmonium-like narrow states $X(3872)$, $Z_b(10610)$, $Z_b(10650)$, $Z_c(3900)$, and $Z_c(4020/4025)$. We interpret the binding mechanism as mostly molecular-like isospin-exchange attraction between two heavy-light mesons in a relative S-wave state. We then generalize it to other systems containing two heavy hadrons which can couple through isospin exchange. The new predicted states include resonances in meson-meson, meson-baryon, baryon-baryon, and baryon-antibaryon channels. These include those giving rise to final states involving a heavy quark $Q=c,b$ and antiquark $\bar Q' = \bar c,\bar b$, namely $D \bar D^*$, $D^* \bar D^*$, $D^* B^*$, $\bar B B^*$, $\bar B^* B^*$, $Σ_c \bar D^*$, $Σ_c B^*$, $Σ_b \bar D^*$, $Σ_b B^*$, $Σ_c \bar Σ_c$, $Σ_c \bar Λ_c$, $Σ_c \bar Λ_b$, $Σ_b \bar Σ_b$, $Σ_b \bar Λ_b$, and $Σ_b \bar Λ_c$, as well as corresponding S-wave states giving rise to $Q Q'$ or $\bar Q \bar Q'$.

hep-ph↗
arXiv2015

Triple product asymmmetries in $Λ_b$ and $Ξ_b$ decays

The LHCb experiment is capable of studying four-body decays of the $b$-flavored baryons $Λ_b$ and $Ξ_b^0$ to charmless final states consisting of charged pions, kaons, and baryons. We remark on the search in such modes for CP-violating triple product asymmetries and for CP rate asymmetries relative to decays involving charmed baryons.

hep-ph↗
arXiv2015

Low-energy photon production in neutrino neutral-current interactions

The search for $ν_μ\to ν_e$ oscillations by the MiniBooNE Collaboration at Fermilab has revealed a low-energy signal which could be due either to electrons produced by $ν_e$ or photons produced by the interaction of the weak neutral current on the target nucleus. One contribution to the latter is a Wess-Zumino-Witten anomaly leading to a term in the Lagrangian proportional to $ε^{μνκλ} Z_μω_νF_{κλ}$. This term is normalized with the help of the known rates for the processes $f_1 \to ργ$ and $τ\to ν_τa_1$. A rate of about 1/4 of that employed in several previous estimates is obtained. As the anomaly term had already been found to play a subdominant role in photon production (e.g., in comparison with $Δ$ excitation and decay), the present estimate reduces its strength even further.

hep-ph↗
arXiv2015

Radiative Return Capabilities of a High-Energy, High-Luminosity $e^+e^-$ Collider

An electron-positron collider operating at a center-of-mass energy $E_{CM}$ can collect events at all lower energies through initial-state radiation (ISR or radiative return). We explore the capabilities for radiative return studies by a proposed high-luminosity collider at $E_{CM}$ = 250 or 90 GeV, to fill in gaps left by lower-energy colliders such as PEP, PETRA, TRISTAN, and LEP. These capabilities are compared with those of the lower-energy $e^+e^-$ colliders as well as hadron colliders such as the Tevatron and the CERN Large Hadron Collider (LHC). Some examples of accessible questions in dark photon searches and heavy flavor spectroscopy are given.

hep-ph↗
arXiv2015

Sterile Neutrinos in $E_{\rm 6}$

The opportunity to accommodate three flavors of sterile neutrinos exists within the exceptional group $E_{\rm 6}$. Implications of this description are discussed.

hep-ph↗
arXiv2014

CDF Results on Heavy Quarks

Some recent CDF results on heavy quarks (mainly $b$) are presented, including baryon masses and lifetimes, CP violation in charmless baryon decays, $B_c$ production, $A_{FB}$ at high $m(b \bar b)$, and excited $B$ mesons. Typographic corrections.

hep-ex↗
arXiv2014

$X(3872)$, $X_b$, and the $χ_{b1}(3P)$ state

We discuss the possible production and discovery channels in $e^+e^-$ and $pp$ machines of the $X_b$, the bottomonium counterpart of $X(3872)$ and the putative isoscalar analogue of the charged bottomonium-like states $Z_b$ discovered by Belle. We suggest that the $X_b$ may be close in mass to the bottomonium state $χ_{b1}(3P)$, mixing with it and sharing its decay channels, just as $X(3872)$ is likely a mixture of a $\bar D D^*$ molecule and $χ_{c1}(2P)$. Consequently, the experiments which reported observing $χ_{b1}(3P)$ might have actually discovered the $X_b$, or a mixture of the two states.

hep-ph↗
arXiv2014

Interpretation of an "edge" in proton-proton scattering

A study of proton-proton collisions at very high energy has revealed a "black disk," whose radius grows with the logarithm of the center-of-mass energy, surrounded by an edge of approximately constant width 1 fm. We interpret this behavior as the maximum length of a QCD string connecting the color triplet and antitriplet components of the proton, and propose further tests of this explanation.

hep-ph↗
arXiv2014

Baryons with two heavy quarks: Masses, production, decays, and detection

The large number of $B_c$ mesons observed by LHCb suggests a sizable cross section for producing doubly-heavy baryons in the same experiment. Motivated by this, we estimate masses of the doubly-heavy $J=1/2$ baryons $Ξ_{cc}$, $Ξ_{bb}$, and $Ξ_{bc}$, and their $J=3/2$ hyperfine partners, using a method which accurately predicts the masses of ground-state baryons with a single heavy quark. We obtain $M(Ξ_{cc}) = 3627 \pm 12$ MeV, $M(Ξ_{cc}^*)= 3690 \pm 12$ MeV, $M(Ξ_{bb}) = 10162 \pm 12$ MeV, $M(Ξ_{bb}^*)= 10184 \pm 12$ MeV, $M(Ξ_{bc}) = 6914 \pm 13$ MeV, $M(Ξ'_{bc}) = 6933 \pm 12$ MeV, and $M(Ξ_{bc}^*) = 6969 \pm 14$ MeV. As a byproduct, we estimate the hyperfine splitting between $B_c^*$ and $B_c$ mesons to be $68 \pm 8$ MeV. We discuss P-wave excitations, production mechanisms, decay modes, lifetimes, and prospects for detection of the doubly heavy baryons.

hep-ph↗
arXiv2014

Asymmetry in $Λ_b$ and $\bar Λ_b$ production

In CMS data at the CERN Large Hadron Collider, the ratio $σ(pp \to \bar Λ_b X)/σ(p p \to Λ_b X)$ appears to fall as the baryons become more forward. Mechanisms which could give rise to this effect are discussed. It is urged that the same physics be explored in data from the LHCb Detector at CERN and the Fermilab Tevatron proton-antiproton collider. In the latter, if such leading-baryon effects are present, one expects $Λ_b$ to be preferentially produced in the direction of the proton and $\bar Λ_b$ to be preferentially produced in the direction of the antiproton.

hep-ph↗
arXiv2014

Three sterile neutrinos in E6

Candidates for unfication of the electroweak and strong interactions include the grand unified groups SU(5), SO(10), and the exceptional group E6. The 27-dimensional fundamental representation of E6 contains exotic fermions, including weak isosinglet quarks of charge -1/3, vector-like weak isodoublet leptons, and neutral leptons which are singlets under both left-handed and right-handed SU(2). These last are candidates for light "sterile" neutrinos, hinted at by some recent short-baseline neutrino experiments. In order to accommodate three families of quarks and charged leptons, an E6 model must contain three 27-plets, each of which contains a sterile neutrino candidate n. The mixing pattern within a 27-plet is described, and experimental consequences are discussed.

hep-ph↗
arXiv2014

Charmless B -> PPP Decays: the Fully-Symmetric Final State

In charmless B -> PPP decays, where P is a pseudoscalar meson, there are six possibilities for the symmetry of the final state. In this paper, for P=pi,K, we examine the properties of the fully-symmetric final state. We present expressions for all 32 B -> PPP decay amplitudes as a function of both SU(3) reduced matrix elements and diagrams, demonstrating the equivalence of diagrams and SU(3). We also give 25 relations among the amplitudes in the SU(3) limit, as well as those that appear when the diagrams E/A/PA are neglected. In the SU(3) limit, one has the equalities \sqrt{2} A(B+ -> K+ pi+ pi-)_{FS} = A(B+ -> K+ K+ K-)_{FS} and \sqrt{2} A(B+ -> pi+ K+ K-)_{FS} = A(B+ -> pi+ pi+ pi-)_{FS}, where FS denotes the fully-symmetric final state. These provide good tests of the standard model that can be carried out now by the LHCb Collaboration.

hep-ph↗
arXiv2013

Flavor SU(3) and $Λ_b$ decays

Some flavor SU(3) results are presented for decays of the $Λ_b$ baryon into non-charmed final states $PB$, where $P$ is a pseudoscalar mesons and $B$ is a spin-1/2 baryon. Although these relations are among amplitudes and hence not yet subject to direct experimental test, they can form the basis for triangle inequalities among decay rates.

hep-ph↗
arXiv2013

Theoretical Issues in Flavor Physics

Quark and lepton flavor physics presents us with a basic question: Can we understand the pattern of masses and mixings of the known quarks and leptons, and how do present and proposed measurements help to advance that goal? Topics discussed include the apparent suppression of new flavor-changing effects, the status of quark and lepton mixing, the implications of new measurements of CP asymmetries in heavy quark decays, the impications of forthcoming experiments on the muon's anomalous magnetic moment and its transitions to an electron, and what we can hope to learn from electric dipole moments.

hep-ph↗
arXiv2013

Leptonic Decays of Charged Pseudoscalar Mesons - 2013

We review the physics of purely leptonic decays of $π^\pm$, $K^\pm$, $D^{\pm}$, $D_s^\pm$, and $B^\pm$ pseudoscalar mesons. The measured decay rates are related to the product of the relevant weak-interaction-based CKM matrix element of the constituent quarks and a strong interaction parameter related to the overlap of the quark and antiquark wave-functions in the meson, called the decay constant $f_P$. The interplay between theory and experiment is different for each particle. Theoretical predictions of $f_B$ that are needed in the $B$ sector can be tested by measuring $f_{D^+}$ and $f_{D_s^+}$ in the charm sector. The lighter $π^{\pm}$ and $K^{\pm}$ mesons provide stringent comparisons between experiment and theory due to the accuracy of both the measurements and the theoretical predictions. An abridged version of this review was prepared for the Particle Data Group's 2014 edition \cite{Previous}.

hep-ex↗
arXiv2013

CP asymmetries in three-body B+- decays to charged pions and kaons

CP asymmetries have been measured recently by the LHCb collaboration in three-body $B^+$ decays to final states involving charged pions and kaons. Large asymmetries with opposite signs at a level of about 60% have been observed in $B^\pm\to π^\pm({\rm or} K^\pm)π^+π^-$ and $B^\pm \to π^\pm K^+K^-$ for restricted regions in the Dalitz plots involving $π^+π^-$ and $K^+K^-$ with low invariant mass. U-spin is shown to predict corresponding $ΔS=0$ and $ΔS=1$ asymmetries with opposite signs and inversely proportional to their branching ratios, in analogy with a successful relation predicted thirteen years ago between asymmetries in $B_s\to K^-π^+$ and $B^0 \to K^+ π^-$. We compare these predictions with the measured integrated asymmetries. Effects of specific resonant or non-resonant partial waves on enhanced asymmetries for low-pair-mass regions of the Dalitz plot are studied in $B^\pm \to π^\pm π^+π^-$. The closure of low-mass $π^+π^-$ and $K^+K^-$ channels involving only $ππ\leftrightarrow K\bar K$ rescattering may explain by CPT approximately equal magnitudes and opposite signs measured in $B^\pm\to π^\pmπ^+π^-$ and $B^\pm \to π^\pm K^+K^-$.

hep-ph↗