scholarly journals Recent LHCb results on charm and charmonium spectroscopy

2019 ◽  
Vol 222 ◽  
pp. 02011
Author(s):  
Viacheslav Matiunin
Keyword(s):  
High Precision ◽  
Lhcb Collaboration ◽  
Charmonium State ◽  
Decay Modes

The recent results on charm and charmonium spectroscopy obtained by the LHCb collaboration are reviewed. In particular, observation of new charmonium state in the decay modes X(3842) → D0D−0 and X(3842) → D+D−, evidence for ηc(1S)π− resonance in B0 → ηc(1S)K+π− decay and observation of three narrow P+c pentaquark candidates decaying to J/ψp are obtained. Also, lifetimes of Ξ+c, Λ+c, Ξ0c and Ω0c baryons are measured with high precision.

scholarly journals Determination of the phase ϕs at LHCb

2018 ◽  
Vol 177 ◽  
pp. 04003
Author(s):  
Varvara Batozskaya
Keyword(s):  
Lhcb Collaboration ◽  
Data Set ◽  
Lhcb Experiment ◽  
Decay Modes

The determination of the mixing-induced CP-violating phase ϕs in the B0s - B0s system is one of the key goals of the LHCb experiment. Using several B0s decay modes it has been measured by the LHCb collaboration exploiting the Run I data set. The first observation of the B0s → ηcϕ and B0s → ηcπ+π- decay modes which can be used to measure ϕs with Run II data is presented.

HEAVY FLAVOUR HADRONIC MOLECULES

2011 ◽  
Vol 26 (03n04) ◽  
pp. 613-615
Author(s):  
P. G. ORTEGA ◽  
D. R. ENTEM ◽  
F. FERNÁNDEZ
Keyword(s):  
Quark Model ◽  
Constituent Quark ◽  
Bound State ◽  
Constituent Quark Model ◽  
Charmonium State ◽  
Decay Modes

The structure and different decay modes of the X(3872) resonance are described in a constituent quark model as dynamically generated by the coupling of a molecular DD* state with a [Formula: see text] state. We also obtain in the D*D* JPC = 1-- channel a bound state that can be identify with the Y(4008) charmonium state. Other possible molecular states in the hidden bottom sector are discussed.

scholarly journals A U-spin prediction for the CP-forbidden transition e+e−→ D0D̄0 → (K+K−)D(π+π−)D

2019 ◽  
Vol 34 (29) ◽  
pp. 1950238 ◽  
Author(s):  
Zhi-Zhong Xing
Keyword(s):  
Cp Violation ◽  
Strong Interaction ◽  
Branching Fraction ◽  
Spin Symmetry ◽  
Lhcb Collaboration ◽  
High Luminosity ◽  
Decay Modes ◽  
Forbidden Transition ◽  
Transition Formula

The LHCb Collaboration has recently reported the discovery of direct CP violation in combined [Formula: see text] and [Formula: see text] decay modes at the [Formula: see text] level. Assuming U-spin symmetry (i.e. [Formula: see text] interchange symmetry) for the strong-interaction parts of these two channels, we find that their corresponding direct CP-violating asymmetries are [Formula: see text] and [Formula: see text]. The CP-forbidden transition [Formula: see text] on the [Formula: see text] resonance is therefore expected to have a branching fraction of [Formula: see text] or smaller under U-spin symmetry, and it can be observed at a high-luminosity super-[Formula: see text]-charm factory if at least [Formula: see text] pairs of coherent [Formula: see text] and [Formula: see text] events are accumulated.

scholarly journals Canonical interpretation of the X(4140) state within the $$^3P_0$$ model

2020 ◽  
Vol 80 (7) ◽  
Author(s):  
Wei Hao ◽  
Guan-Ying Wang ◽  
En Wang ◽  
Guan-Nan Li ◽  
De-Min Li
Keyword(s):  
Quark Model ◽  
High Precision ◽  
Precision Measurement ◽  
Mass Spectra ◽  
Lhcb Collaboration ◽  
Experimental Measurements ◽  
Strong Decay ◽  
High Precision Measurement ◽  
Decay Properties ◽  
Small Width

Abstract Recently, the LHCb Collaboration has confirmed the state X(4140), with a mass $$M=4146.5\pm 4.5^{+4.6}_{-2.8}$$M=4146.5±4.5-2.8+4.6 MeV, and a much larger width $$\Gamma =83\pm 21^{+21}_{-14}$$Γ=83±21-14+21 MeV than the previous experimental measurements, which has confused the understanding of its nature. We will investigate the possibility of the $$\chi _{c1}(3P)$$χc1(3P) interpretation for the X(4140), considering the mass spectra predicted in the quark model, and the strong decay properties within the $$^3P_0$$3P0 model. We also predict the strong decay properties of the charmonium states $$\chi _{c0}(3P)$$χc0(3P) and $$\chi _{c2}(3P)$$χc2(3P). Our results show that the X(4140) state with the small width given in PDG can be explained as the charmonium state $$\chi _{c1}(3P)$$χc1(3P) in the $$^3P_0$$3P0 model, and high precision measurement of the width of the X(4140) is crucial to understand its nature.

Automatic measurement of SAED patterns from asbestos minerals

1988 ◽  
Vol 46 ◽  
pp. 846-847
Author(s):  
J. C. Russ ◽  
T. Taguchi ◽  
P. M. Peters ◽  
E. Chatfield ◽  
J. C. Russ ◽  
...  
Keyword(s):  
Diffraction Pattern ◽  
High Precision ◽  
Diffraction Data ◽  
Automatic Measurement ◽  
Automatic Method ◽  
Important Method ◽  
X Ray ◽  
Integrated Intensity ◽  
Asbestiform Minerals ◽  
True Center

Conventional SAD patterns as obtained in the TEM present difficulties for identification of materials such as asbestiform minerals, although diffraction data is considered to be an important method for making this purpose. The preferred orientation of the fibers and the spotty patterns that are obtained do not readily lend themselves to measurement of the integrated intensity values for each d-spacing, and even the d-spacings may be hard to determine precisely because the true center location for the broken rings requires estimation. We have implemented an automatic method for diffraction pattern measurement to overcome these problems. It automatically locates the center of patterns with high precision, measures the radius of each ring of spots in the pattern, and integrates the density of spots in that ring. The resulting spectrum of intensity vs. radius is then used just as a conventional X-ray diffractometer scan would be, to locate peaks and produce a list of d,I values suitable for search/match comparison to known or expected phases.

On effects of non-systematic reflections on weak-beam images of partial dislocations

1991 ◽  
Vol 49 ◽  
pp. 688-689
Author(s):  
K. Z. Botros ◽  
S. S. Sheinin
Keyword(s):  
High Precision ◽  
Stacking Fault ◽  
Important Application ◽  
Stacking Fault Energy ◽  
Sharp Peak ◽  
Weak Beam ◽  
Partial Dislocations ◽  
Deviation Parameter ◽  
Beam Diffraction

The main features of weak beam images of dislocations were first described by Cockayne et al. using calculations of intensity profiles based on the kinematical and two beam dynamical theories. The feature of weak beam images which is of particular interest in this investigation is that intensity profiles exhibit a sharp peak located at a position very close to the position of the dislocation in the crystal. This property of weak beam images of dislocations has an important application in the determination of stacking fault energy of crystals. This can easily be done since the separation of the partial dislocations bounding a stacking fault ribbon can be measured with high precision, assuming of course that the weak beam relationship between the positions of the image and the dislocation is valid. In order to carry out measurements such as these in practice the specimen must be tilted to "good" weak beam diffraction conditions, which implies utilizing high values of the deviation parameter Sg.

Digital differential hysteresis iimage processing displays what the microscope acquires but the eye can't see

1995 ◽  
Vol 53 ◽  
pp. 642-643
Author(s):  
Klaus-Ruediger Peters
Keyword(s):  
Image Processing ◽  
Visual System ◽  
High Precision ◽  
Image Data ◽  
Processing Technology ◽  
Output Data ◽  
Contrast Resolution ◽  
Pixel Intensity ◽  
Data Reading ◽  
Hysteresis Properties

Differential hysteresis processing is a new image processing technology that provides a tool for the display of image data information at any level of differential contrast resolution. This includes the maximum contrast resolution of the acquisition system which may be 1,000-times higher than that of the visual system (16 bit versus 6 bit). All microscopes acquire high precision contrasts at a level of <0.01-25% of the acquisition range in 16-bit - 8-bit data, but these contrasts are mostly invisible or only partially visible even in conventionally enhanced images. The processing principle of the differential hysteresis tool is based on hysteresis properties of intensity variations within an image.Differential hysteresis image processing moves a cursor of selected intensity range (hysteresis range) along lines through the image data reading each successive pixel intensity. The midpoint of the cursor provides the output data. If the intensity value of the following pixel falls outside of the actual cursor endpoint values, then the cursor follows the data either with its top or with its bottom, but if the pixels' intensity value falls within the cursor range, then the cursor maintains its intensity value.

High precision measurement of the SOS surface thickness in the rough phase

1991 ◽  
Vol 1 (12) ◽  
pp. 1669-1673 ◽  
Author(s):  
Hans Gerd Evertz ◽  
Martin Hasenbusch ◽  
Mihail Marcu ◽  
Klaus Pinn ◽  
Sorin Solomon
Keyword(s):  
High Precision ◽  
Precision Measurement ◽  
High Precision Measurement ◽  
Surface Thickness
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