Dalitzplot analysis of particle decays is an important and. This allows a modelindependentmeasurement ofthemassdependence ofthei. Work supported in part by us department of energy contract deac0276sf00515. We fit the dalitz plot distribution using an isobar model and measure the magnitudes and phases of the decay coefficients. Dalitz plot analysis of heavy quark mesons decays 4. Typically, for m abc, use invariant mass squared brian lindquist, dalitz plots sass talk 17 2 ac 2 x ab ym 2 b a 2 m ab p p 2 m bc. The model assumes, for example, a dmeson decays into an excited state r kk. The scatter plot in m2 ab versus m 2 bc is the dalitz plot. If one has a sample of events of such a character, a question arises as to how to analyze the data to obtain useful information about the final state. At each e 3, e 4 point in such a dalitz plot the neutron energy e 5 and the np relative energy e 35 each have definite values because of energymomentum conservation. Tr is the dynamical function describing the resonance r. They fit the dalitz plot distribution using an isobar model and report the measured values of magnitudes and phases of the production coefficients. The dalitz plot was an important contributor to the tautheta puzzle of the 1950s, which was eventually solved by the discovery of parity violation.
Dalitz plot analy sis of bsuperscript plus or minus pi. Relativistic usually dont use the original dalitz plot variables. The kinematics of a threebody decay can be completely described using two variables. The amplitude for modeling the dalitz plot is a phenomenological object. The depopulation in the center of both the 4 and z 892 bands is. The data are fitted to a model consisting of a sum of relativistic breitwigner. Measurement of the i 12 kswave amplitude from dalitz. A modelindependent dalitz plot analysis of bdk with d. Introduction to dalitz plot analysis tim gershon university of warwick 479. On the analysis of taumeson data and the nature of the taumeson. Dalitz plot analysis of b d connecting repositories. In addition, he is known for other key developments in particle physics. Pdf we report a dalitzplot analysis of the charmless hadronic decays of neutral b mesons to k0.
The dalitz plot is a ternary plot often used in particle physics to represent the relative frequency of various kinematically distinct manners in which the products of certain otherwise similar threebody decays may move apart. Work supported in part by us department of energy contract deac0276sf00515 hepex. It will definitely keep us company over the next few years some complications have already emerged expecially in the charm field others unexpected will only become clearer when we delve deeper into the beauty sector bs will be a new chapter plb645 2007 201. In this analysis we apply a formalism similar to that used in other cleo dalitz plot analyses, 14.
The purpose of the binned dalitz plot fit is to measure the cpviolating parameters x and y, as introduced in section 2. We select 67086 candidate events for the dalitz plot analysis 12. His various fundamental contributions have led to practitioners in. Clns 051908 cleo 053 search for d mixing in the dalitz plot. National central university, chungli, taiwan 320, republic of china. The analysis uses a 384 fb1 data sample recorded by the babar detector at the pepii asymmetric.
Dalitz plot analy sis of bsuperscript plus or minus. Normalization set n variables pdf and dataset have in common pdf is projected over all unplotted observables the plot variable set x the plotted dimensions of the pdf for a 1d rooplot this is always 1 variable the projection set p is n x the projected pdf function is. Prominent peaks occur in the dalitz plot due to pp qfs and due to np fsi. At birmingham he completed his thesis demonstrating that the electrically neutral pion could decay into a photon and an electronpositron pair, now known as a dalitz pair. Dalitz plot analysis of b d slac national accelerator. The focus collaboration has studied this decay in a dalitz plot analysis in an unpublished thesis 4 and a conference presentation 5. Introduction dalitz plots from heavy meson decays have been conventionally analyzed with isobar models. We express the amplitude for d0 to decay via the jth quasitwo. Nuclear and high energy physics, mathematical physics, physics and astronomy all. Wright lawrence livermore national laboratory, livermore, california 94550, usa i.
Dalitz had applied this technique for the first time to k l decays to determine spin and parity of the then known. Dalitz plot analyses of decays of heavy mesons d, b mesons very popular in recent years. Grabowski and ricardo graciani diaz and eugeni grauges and elena graverini. This histograms is used to weight the signal pdf in the dalitz plot fit. Additional information can be obtained via multibody decays n 2. Consider either a production reaction or the decay of a particle leading to a final state consisting of three or more particles. One approach for solving this problem, adopted by babar 46 and belle 79, isto use an amplitudemodel. The term dalitz decay itself is never used without a meson as far as i saw in the search, so i changed my answer. Dalitz plot analysis is teaching us much about hadronic decays. These forms are very general and satisfy all the requirements stated at the beginning. We would like to show you a description here but the site wont allow us. There are several commands which will direct output to a file instead of the screen.
Dalitz plots are a powerful tool for studying three body systems. The has a small effective radius r, so larger angular momenta. Dec 20, 2007 pdf we present for the first time a measurement of the weak phase 2. D three body decay dabc decaying through a resonance rab. Our data are fit to a model consisting of a sum of ekeitwigner amplitudes for the intermediate iwobody resonant decay modes. Nonresonant or background flat homogeneous distribution. In the absence of any reconstruction effects, the dp pdf would be. Many elementaryparticle decay processes and highenergy nuclear reactions lead to final states consisting of three particles which may be denoted by a, b, c, with mass values m a, m b, m c.
We find no evidence of cp violation for the individual components of the isobar model. If m2 is constant, the kinematically allowed region of the plot will be populated uniformly with events. The dalitz plot for data and the kinematic b oundary corresponding to m. Dalitz plot article about dalitz plot by the free dictionary. The latest versions of adobe reader do not support viewing pdf files within firefox on mac os and if you are using a modern intel mac, there is no official plugin for viewing pdf. The dalitz decay is when a virtual photon from 2 photon decay of. Any variation in the population over the dalitz plot is due to dynamic rather than kinematic e. Dalitz plot analy sis of bsuperscript plus or minuspisuperscript plus or minuspisuperscript plus or minuspisuperscript minus ov er plus decay s the mit faculty has made this article openly available. Dalitz plot technique threebody decays having reasonable. Poluektov2 1 massachusetts institute of technology, cambridge, ma, united states 2 department of physics, university of warwick, coventry, united kingdom abstract two of the most powerful methods currently used to determine the angle. Techniques of amplitude analysis college of william mary williamsburg, virginia, usa wed.
The latest versions of adobe reader do not support viewing pdf files within firefox on mac os and if you are using a modern intel mac, there is no official plugin for viewing pdf files within the browser window. Pictorial representation in highenergy nuclear physics for data on the distribution of certain threeparticle configurations. Bdk dalitz plot analyses for gf 3 at belle yoshiyuki onuki university of tokyo on behalf of belle 1 37th international conference on high energy physics, 29 july 2014, valencia. A dalitz plot analysis of approximately 12500 d0 events reconstructed in the hadronic decay d0k.
A double dalitz decay is into four leptons, so that establishes that the usage is for 2 lepton final states. A comparison between the present measurement and those from previous experiments indicates similar 2. D threebody decay dabc decaying through a resonance rab. Dalitz plots play a central role in the discovery of new particles in current highenergy physics experiments, including higgs boson research, and are tools in exploratory efforts that might open avenues beyond the standard model. Mckenna university of british columbia, vancouver, british columbia, canada v6t 1z1 a.