Weheraeusseminar physics at lhcb 26 april 2011 tim gershon introduction to dalitz plot analysis. In the absence of any reconstruction effects, the dp pdf would be. Introduction to dalitz plot analysis tim gershon university of warwick 479. Giubega and konstantin gizdov and dmitry golubkov and a. 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. Xvi international conference on hadron spectroscopy, newport news, va, usa sudeep ghosh of clas, for the lmdcaa indian institute of technology indore, india september 2015 sudeep ghosh of clas, for the lmdcaa dalitz plot analysis of. A modelindependent dalitz plot analysis of bdk with d.
If m2 is constant, the kinematically allowed region of the plot will be populated uniformly with events. The model assumes, for example, a dmeson decays into an excited state r kk. We fit the dalitz plot distribution using an isobar model and measure the magnitudes and phases of the decay coefficients. Pdf we report a dalitzplot analysis of the charmless hadronic decays of neutral b mesons to k0. Dec 20, 2007 pdf we present for the first time a measurement of the weak phase 2.
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. One approach for solving this problem, adopted by babar 46 and belle 79, isto use an amplitudemodel. 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. 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. The dalitz plot for data and the kinematic b oundary corresponding to m.
Dalitz plot analyses of decays of heavy mesons d, b mesons very popular in recent years. They fit the dalitz plot distribution using an isobar model and report the measured values of magnitudes and phases of the production coefficients. In this analysis we apply a formalism similar to that used in other cleo dalitz plot analyses, 14. The dalitz plot was an important contributor to the tautheta puzzle of the 1950s, which was eventually solved by the discovery of parity violation. The dalitz plot is symmetric under the interchange of likesign pions, so. D threebody decay dabc decaying through a resonance rab. The scatter plot in m2 ab versus m 2 bc is the dalitz plot. Techniques of amplitude analysis college of william mary williamsburg, virginia, usa wed. 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. Clns 051908 cleo 053 search for d mixing in the dalitz plot. The focus collaboration has studied this decay in a dalitz plot analysis in an unpublished thesis 4 and a conference presentation 5. On the analysis of taumeson data and the nature of the taumeson. 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.
Relativistic usually dont use the original dalitz plot variables. In addition, he is known for other key developments in particle physics. Dalitz plot technique threebody decays having reasonable. History of the dalitz plot dalitzs original plot nonrelativistic. Prominent peaks occur in the dalitz plot due to pp qfs and due to np fsi. 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. The term dalitz decay itself is never used without a meson as far as i saw in the search, so i changed my answer. We would like to show you a description here but the site wont allow us. Nuclear and high energy physics, mathematical physics, physics and astronomy all. Dalitz plot analysis of heavy quark mesons decays 4. 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.
Work supported in part by us department of energy contract deac0276sf00515 hepex. There are other ways, not involving dcs decays, in which d0 and d0 singly cabibbosuppressed decays can populate the same dalitz plot. A double dalitz decay is into four leptons, so that establishes that the usage is for 2 lepton final states. Introduction dalitz plots from heavy meson decays have been conventionally analyzed with isobar models. His various fundamental contributions have led to practitioners in. Grabowski and ricardo graciani diaz and eugeni grauges and elena graverini.
A comparison between the present measurement and those from previous experiments indicates similar 2. 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. Dalitz plot analysis is teaching us much about hadronic decays. Any variation in the population over the dalitz plot is due to dynamic rather than kinematic e. We find no evidence of cp violation for the individual components of the isobar model.
Dalitz plots give information about particle masses, lifetimes, spins, and interference. 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. This histograms is used to weight the signal pdf in the dalitz plot fit. There are several commands which will direct output to a file instead of the screen. The kinematics of a threebody decay can be completely described using two variables. 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. Dalitzplot analysis of particle decays is an important and. Dalitz plot analysis of heavy quark mesons decays 2.
Our data are fit to a model consisting of a sum of ekeitwigner amplitudes for the intermediate iwobody resonant decay modes. These forms are very general and satisfy all the requirements stated at the beginning. D three body decay dabc decaying through a resonance rab. Now, however, we generalize to the case where the timedependent state is a mixture of d0 and d0 so the dalitz plot distribution depends also on x and y. Work supported in part by us department of energy contract deac0276sf00515. Dalitz plots are a powerful tool for studying three body systems. We express the amplitude for d0 to decay via the jth quasitwo. Consider either a production reaction or the decay of a particle leading to a final state consisting of three or more particles.
Dalitz plot analysis of b d slac national accelerator. The has a small effective radius r, so larger angular momenta. Dalitz plot article about dalitz plot by the free dictionary. Pictorial representation in highenergy nuclear physics for data on the distribution of certain threeparticle configurations. Dalitz had applied this technique for the first time to k l decays to determine spin and parity of the then known. 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. 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 analysis of b d connecting repositories. Measurement of the i 12 kswave amplitude from dalitz. The data are fitted to a model consisting of a sum of relativistic breitwigner. Wright lawrence livermore national laboratory, livermore, california 94550, usa i. Tr is the dynamical function describing the resonance r.
National central university, chungli, taiwan 320, republic of china. We select 67086 candidate events for the dalitz plot analysis 12. Dalitz plot analy sis of bsuperscript plus or minus. This allows a modelindependentmeasurement ofthemassdependence ofthei. 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. The purpose of the binned dalitz plot fit is to measure the cpviolating parameters x and y, as introduced in section 2. A dalitz plot analysis of approximately 12500 d0 events reconstructed in the hadronic decay d0k. 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. Mckenna university of british columbia, vancouver, british columbia, canada v6t 1z1 a. The analysis uses a 384 fb1 data sample recorded by the babar detector at the pepii asymmetric. Additional information can be obtained via multibody decays n 2. Nonresonant or background flat homogeneous distribution. The dalitz decay is when a virtual photon from 2 photon decay of.
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