2,668,924 research outputs found
Constraints on models for the Higgs boson with exotic spin and parity in final states
We present constraints on models containing non-standard model values for the
spin and parity of the Higgs boson, , in up to 9.7~fb of
collisions at 1.96~TeV collected with the D0 detector
at the Fermilab Tevatron Collider. These are the first studies of Higgs boson
with fermions in the final state. In the , , and final states, we compare the standard model (SM) Higgs boson
prediction, , with two alternative hypotheses, and
. We use a likelihood ratio to quantify the degree to which our
data are incompatible with non-SM predictions for a range of possible
production rates. Assuming that the production rate in the signal models
considered is equal to the SM prediction, we reject the and
hypotheses at the 97.6 CL and at the 99.0 CL,
respectively. The expected exclusion sensitivity for a
() state is at the 99.86 (99.94) CL. Under the hypothesis
that our data is the result of a combination of the SM-like Higgs boson and
either a or a signal, we exclude a
fraction above 0.80 and a fraction above 0.67 at the 95 CL.
The expected exclusion covers () fractions above
0.54 (0.47).Comment: 13 Figures, 3 Tables, 19 pages. Accepted by Phys. Rev. Let
New combinations in the genera Atractylocarpus and Metzleria
The type species of Atractylocarpus has revealed to be a species of a genus which was later introduced as Camylopodiella. To avoid taxonomic confusions, it was proposed to keep the current use of Atractylocarpus and Campylopodiella by amending the genus Atractylocarpus. This proposal was rejected by the ICBN committee. Therefore the valid genus for all species so far comprised in Atractylocarpus is Metzleria and all species so far included in Campylopodiella must be transferred to Atractylocarpus. Accoringly, all necessary new combinations are introduced here: Atractylocarpus himalayanus (Broth.) J.-P. Frahm , Atractylocarpus malagensis (Herz.) J.-P. Frahm Metzleria comosa (Dix.) J.-P. Frahm, Metzleria madagascariensis (Thér.) J.-P. Frahm, Metzleria nana (Williams) J.-P. Frahm, Metzleria patagonica (Herz. et Thér.) J.-P. Frahm
Coupled-channel analysis of the possible , and molecular states
We perform a coupled-channel study of the possible deuteron-like molecules
with two heavy flavor quarks, including the systems of with
double charm, with double bottom and
with both charm and bottom, within the
one-boson-exchange model. In our study, we take into account the S-D mixing
which plays an important role in the formation of the loosely bound deuteron,
and particularly, the coupled-channel effect in the flavor space. According to
our calculation, the states and
with double charm, the states
,
and
with double bottom, and
the states and
with both charm and bottom are good
molecule candidates. However, the existence of the states
with double charm and
with both charm and bottom is ruled out.Comment: 1 figure added, published in Physical Review
Magnetic Moments of Pentaquarks
If the of and pentaquarks is really found to
be by future experiments, they will be accompanied by
partners in some models. It is reasonable to expect that
these states will also be discovered in the near future with
the current intensive experimental and theoretical efforts. We estimate
pentaquark magnetic moments using different models.Comment: 13 page
On heavy-light meson resonances and chiral symmetry
We study heavy-light meson resonances with quantum numbers J^P=0^+ and
J^P=1^+ in terms of the non-linear chiral SU(3) Lagrangian. At leading order a
parameter-free prediction is obtained for the scattering of Goldstone bosons
off heavy-light pseudo-scalar and vector mesons once we insist on approximate
crossing symmetry of the unitarized scattering amplitude. The recently
announced narrow open charm states observed by the BABAR and CLEO
collaborations are reproduced. We suggest the existence of states that form an
anti-triplet and a sextet representation of the SU(3) group. In particular, so
far unobserved narrow isospin-singlet states with negative strangeness
(I,S)=(0,-1) are predicted at 2361 MeV J^P=0^+ and 2501 MeV (J^P=1^+).
Similarly, open bottom states are found at 5719 MeV (J^P=0^+) and 5622 MeV
(J^P=1^+). Additional narrow states of mass 5580 MeV (J^P=0^+) and 5650 MeV
(J^P=1^+) with widths of about 50 MeV are obtained in the (I,S)=(1,1) sector.
For the anti-triplet states our results differ most significantly from
predictions that are based on a linear realization of the chiral SU(3) symmetry
in the open bottom sector. Strongly bound 0^+-and 1^+-states with (I,S)=(0,1)
at 5507 MeV and 5553 MeV are predicted.Comment: revised manuscript: improved discussion and minor correction
Charmed baryon Sigmac(2800) as a ND hadronic molecule
The isotriplet Sigmac(2800) baryon with possible quantum numbers J(P) =
1/2(+), 1/2(-) or 3/2(+), 3/2(-) is considered as a hadronic molecule composed
of a nucleon and a D meson. We determine the strong two-body decay widths
Sigmac to Lambdac + pi which are shown to be consistent with current data for
the J(P) = 1/2(+) and J(P) = 3/2(-) assignments.Comment: 8 pages, 2 figure
Density Functionals in the Presence of Magnetic Field
In this paper density functionals for Coulomb systems subjected to electric
and magnetic fields are developed. The density functionals depend on the
particle density, , and paramagnetic current density, . This
approach is motivated by an adapted version of the Vignale and Rasolt
formulation of Current Density Functional Theory (CDFT), which establishes a
one-to-one correspondence between the non-degenerate ground-state and the
particle and paramagnetic current density. Definition of -representable
density pairs is given and it is proven that the set of
-representable densities constitutes a proper subset of the set of
-representable densities. For a Levy-Lieb type functional , it
is demonstrated that (i) it is a proper extension of the universal
Hohenberg-Kohn functional, , to -representable densities,
(ii) there exists a wavefunction such that
, where is the Hamiltonian without
external potential terms, and (iii) it is not convex. Furthermore, a convex and
universal functional is studied and proven to be equal the convex
envelope of . For both and , we give upper and lower
bounds.Comment: 26 page
Open-charm meson resonances with negative strangeness
We study heavy-light meson resonances with quantum numbers J^P=0^+ and
J^P=1^+ in terms of the non-linear chiral SU(3) Lagrangian. Adjusting the free
parameters that arise at subleading order to reproduce the mass of the D(2420)
resonance as well as the new states established recently by the BABAR, CLEO and
BELLE collaborations we obtain refined masses for the anti-triplet and sextet
states. Bound states of antikaons at the D(1867) and D(2008) mesons are
predicted at 2352 MeV (J^P=0^+) and 2416 MeV (J^P=1^+). In addition we
anticipate a narrow scalar state of mass 2389 MeV with (I,S)=(1/2,0)Comment: 12 pages, 3 figure
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