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Lattice studies present a qualitative guide, but in most cases theoretical expectations nonetheless depend on models as well as a quantitative basic theory continues to be missing. four.four Strong coupling s There are numerous heavy-quark systems that happen to be suitable for [https://dx.doi.org/10.2196/jmir.6472 title= jmir.6472] a precise determination of s , mostly involving quarkonium, or quarkonium-like, configurations, which are fundamentally governed by the sturdy interactions. One particular can typically take advantage of non-relativistic powerful theories, high-order perturbative calculations which can be available for these systems, and of progress in lattice computations. Using moments of heavy-quark correlators calculated around the lattice, plus the continuum perturbation theory outcomes for them [1129], the HPQCD collaboration has obtained s (M Z ) = 0.1183 ?0.0007 [2]. This result is very close, each inside the central worth and error, for the one particular obtained from measuring many quantities associated to short-distance Wilson loops by precisely the same collaboration [2]. The energy amongst two static sources within the basic representation, as a function of its separation, can also be appropriate to get a precise s extraction. The perturbative computation has now reached a three-loop level [1130?135], and lattice-QCD results with Nf = two + 1 sea quarks are accessible [1136]. A comparison from the two offers s (M Z ) = 0.1156+0.0021 [1137]. New lattice information for -0.0022 the static energy, like points at shorter distances, might be out there in the close to future, and an update with the outcome for s might be expected, in principle with reduced errors. Quarkonium decays, or a lot more precisely ratios of their widths (used to minimize the sensitivity to long-distance effects), were readily identified as an excellent spot for s extractions. One complication could be the dependence on coloroctet configurations. The ideal ratio for s extractions, within the sense that the sensitivity to color-octet matrix components and relativistic effects is most lowered, turns out to be R := ( X )/ ( X ), from which one obtains s (M Z ) = 0.119+0.006 [1138]. The primary uncertainty in this -0.005 result comes in the systematic errors of your experimental measurement of R [1139]. Belle may very well be able to create an enhanced measurement of R , which may perhaps translate into a greater s determination. Very lately the CMS collaboration has presented a determination of s from the measurement from the inclusive cross ?section for t t production, by [http://brycefoster.com/members/bear74peony/activity/812810/ http://brycefoster.com/members/bear74peony/activity/812810/] comparing it with all the NNLO QCD prediction. The [https://dx.doi.org/10.1080/17470919.2015.1029593 title= 17470919.2015.1029593] evaluation is performed with diverse NNLO PDF sets, and the result from the NNPDF set is used as the most important outcome. Employing m t = 173.two ?1.4 GeV, s (M Z ) = 0.1151+0.0033 is obtained [1140], the initial s -0.0032 determination from top-quark production.Eur. Phys. J. C (2014) 74:Web page 75 of 2414.five Heavy quarkonium production Forty years after the discovery of the J/, the mechanism underlying quarkonium production has nevertheless not been clarified. Until the mid-90s largely the standard color singlet model was utilized in perturbative cross section calculations. The dramatic failure to describe J/ production in the Tevatron led, nonetheless, to a search for option explanations.
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S) (n = 1, two, 3) transitions with partial widths of 300 - 400 keV [1116]. Recently Belle
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S) (n = 1, two, three) transitions with partial widths of 300 - 400 keV [1116]. Recently Belle reported preliminary outcomes around the observation of (5S) (1S, 2S) and (5S) + - (1D) with anomalously significant prices [985]. It's proposed that these anomalies are because of rescatterings [1123,1124]. The big branching fraction from the (4S) (1S) decay observed in 2010 by BaBar could have a similar origin [1125]. The mechanism can be regarded as either as a rescatter??ing on the D D or B B mesons, or as a [http://www.tongji.org/members/shadow2pantry/activity/516070/ http://www.tongji.org/members/shadow2pantry/activity/516070/] contribution of the molecular component towards the quarkonium wave function. ?The model in which Y (4260) is really a D1 (2420) D molecule naturally explains the high probability of the intermediate molecular resonance within the Y (4260) + - J/ transitions [1126,1127] and predicts the Y (4260) X (3872) transitions with high prices [1128]. Such transitions have not too long ago been observed by BES III, with [1107] K + - (2S)2981 Page 74 ofEur. Phys. J. C (2014) 74:[e+ e- X (3872)] 11 . [e+ e- + - J/](4.15)Regardless of striking similarities in between the observations in the charmonium and bottomonium sectors, you'll find also clear variations. In the charmonium sector, every of the Y (3915), (4040), (4160), Y (4260), Y (4360) and Y (4660) decays to only one certain final state with charmonium [ J/, J/, + - J/ or + - (2S)]. Inside the bottomonium sector, there is certainly a single state with anomalous properties, the (5S), and it decays to distinctive channels with comparable prices [ + - (nS), + - h b (m P), + - (1D), (nS)]. There is no common model describing these peculiarities. To explain the affinity from the charmonium-like states to some particular channels, the notion of "hadrocharmonium" was proposed in [1084]. It really is a heavy quarkonium embedded into a cloud of light hadron(s), therefore the fallapart decay is dominant. Hadrocharmonium could also deliver an explanation for [https://dx.doi.org/10.1089/jir.2014.0001 title= jir.2014.0001] the charged charmonium-like states Z (4430)+ , Z (4050)+ and Z (4250)+ . four.three.five Summary Quarkonium spectroscopy enjoys an intensive flood of new benefits. The number of spin-singlet bottomonium states has elevated from 1 to 4 more than the final 2 years, including a far more precise measurement of your b (1S) mass, 11 MeV away in the PDG2012 typical. There is evidence for one of the two nonetheless missing narrow charmonium states anticipated ??within the area amongst the D D and D D thresholds. Observations and detailed studies from the charged bottomoniumlike states Z b (10610) and Z b (10650) and initial benefits on the charged charmonium-like states Z c open a rich phenomenological field to study exotic states near open flavor thresholds. There's also considerable progress as well as a extra clear experimental scenario for the highly excited heavy quarkonium states above open flavor thresholds. Current highlights incorporate confirmation in the Y (4140) state by CMS and D0, observation of your decays (4040, 4160) J/ by Belle, measurement on the energy dependence with the e+ e- + - h c cross section by BES III, observation of your Y (4260) X (3872) by BES III and determination on the Z (4430) spin arity from complete amplitude analysis by Belle.

Revision as of 06:04, 3 January 2018

S) (n = 1, two, 3) transitions with partial widths of 300 - 400 keV [1116]. Recently Belle S) (n = 1, two, three) transitions with partial widths of 300 - 400 keV [1116]. Recently Belle reported preliminary outcomes around the observation of (5S) (1S, 2S) and (5S) + - (1D) with anomalously significant prices [985]. It's proposed that these anomalies are because of rescatterings [1123,1124]. The big branching fraction from the (4S) (1S) decay observed in 2010 by BaBar could have a similar origin [1125]. The mechanism can be regarded as either as a rescatter??ing on the D D or B B mesons, or as a http://www.tongji.org/members/shadow2pantry/activity/516070/ contribution of the molecular component towards the quarkonium wave function. ?The model in which Y (4260) is really a D1 (2420) D molecule naturally explains the high probability of the intermediate molecular resonance within the Y (4260) + - J/ transitions [1126,1127] and predicts the Y (4260) X (3872) transitions with high prices [1128]. Such transitions have not too long ago been observed by BES III, with [1107] K + - (2S)2981 Page 74 ofEur. Phys. J. C (2014) 74:[e+ e- X (3872)] 11 . [e+ e- + - J/](4.15)Regardless of striking similarities in between the observations in the charmonium and bottomonium sectors, you'll find also clear variations. In the charmonium sector, every of the Y (3915), (4040), (4160), Y (4260), Y (4360) and Y (4660) decays to only one certain final state with charmonium [ J/, J/, + - J/ or + - (2S)]. Inside the bottomonium sector, there is certainly a single state with anomalous properties, the (5S), and it decays to distinctive channels with comparable prices [ + - (nS), + - h b (m P), + - (1D), (nS)]. There is no common model describing these peculiarities. To explain the affinity from the charmonium-like states to some particular channels, the notion of "hadrocharmonium" was proposed in [1084]. It really is a heavy quarkonium embedded into a cloud of light hadron(s), therefore the fallapart decay is dominant. Hadrocharmonium could also deliver an explanation for title= jir.2014.0001 the charged charmonium-like states Z (4430)+ , Z (4050)+ and Z (4250)+ . four.three.five Summary Quarkonium spectroscopy enjoys an intensive flood of new benefits. The number of spin-singlet bottomonium states has elevated from 1 to 4 more than the final 2 years, including a far more precise measurement of your b (1S) mass, 11 MeV away in the PDG2012 typical. There is evidence for one of the two nonetheless missing narrow charmonium states anticipated ??within the area amongst the D D and D D thresholds. Observations and detailed studies from the charged bottomoniumlike states Z b (10610) and Z b (10650) and initial benefits on the charged charmonium-like states Z c open a rich phenomenological field to study exotic states near open flavor thresholds. There's also considerable progress as well as a extra clear experimental scenario for the highly excited heavy quarkonium states above open flavor thresholds. Current highlights incorporate confirmation in the Y (4140) state by CMS and D0, observation of your decays (4040, 4160) J/ by Belle, measurement on the energy dependence with the e+ e- + - h c cross section by BES III, observation of your Y (4260) X (3872) by BES III and determination on the Z (4430) spin arity from complete amplitude analysis by Belle.

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