排序方式: 共有15条查询结果,搜索用时 31 毫秒
1.
S. V. Golovkin A. P. Kozhevnikov V. P. Kubarovsky A. I. Kulyavtzev V. F. Kurshetsov A. I. Kushnirenko L. G. Landsberg V. V. Molchanov V. A. Mukhin V. I. Solyanik D. V. Vavilov V. A. Victorov M. Ya. Balatz G. V. Dzubenko A. D. Kamenskii G. K. Kliger V. Z. Kolganov V. S. Lakaev G. S. Lomkatzi A. P. Nilov V. T. Smolyankin V. E. Vishnyakov 《Zeitschrift fur Physik C Particles and Fields》1995,68(4):585-594
In the experiments at the SPHINX facility in 70 GeV proton beam of the IHEP accelerator the coherent diffractive production reactions on carbon nucleip+C [(1385)0
K
++C andp+C[0
K
+]+C were investigated. The evidences for new baryon states were obtained in the study of hyperon-kaon effective mass spectra in these two reactions:X (2050) with massM=(2052±6) MeV and width =(35
–35
+22
) MeV inM[(1385)0
K
+] andX(2000) withM=1999±6 MeV and =91±17 MeV inM[0
K
+]. The unusual features of these massive states (small enough decay widths, anomalously large branching ratios for decays with strange particles emission) make them very serious candidates for cryptoexotic pentaquark baryons with hidden strangeness. 相似文献
2.
Mattson M Alkhazov G Atamantchouk AG Balatz MY Bondar NF Cooper PS Dauwe LJ Davidenko GV Dersch U Dolgolenko AG Dzyubenko GB Edelstein R Emediato L Endler AM Engelfried J Eschrich I Escobar CO Evdokimov AV Filimonov IS Garcia FG Gaspero M Giller I Golovtsov VL Gouffon P Gülmez E Kangling H Iori M Jun SY Kaya M Kilmer J Kim VT Kochenda LM Konorov I Kozhevnikov AP Krivshich AG Krüger H Kubantsev MA Kubarovsky VP Kulyavtsev AI Kuropatkin NP Kurshetsov VF Kushnirenko A Kwan S Lach J Lamberto A 《Physical review letters》2002,89(11):112001
We observe a signal for the doubly charmed baryon Xi(+)(cc) in the charged decay mode Xi(+)(cc)-->Lambda(+)(c)K-pi(+) in data from SELEX, the charm hadroproduction experiment at Fermilab. We observe an excess of 15.9 events over an expected background of 6.1+/-0.5 events, a statistical significance of 6.3sigma. The observed mass of this state is 3519+/-1 MeV/c(2). The Gaussian mass width of this state is 3 MeV/c(2), consistent with resolution; its lifetime is less than 33 fs at 90% confidence. 相似文献
3.
S.V. Golovkin A.P. Kozhevnikov V.P. Kubarovsky V.F. Kurshetsov L.G. Landsberg V.V. Molchanov V.A. Mukhin S.V. Petrenko V.A. Senko D.V. Vavilov V.A. Victorov V.Z. Kolganov G.S. Lomkatsi A.F. Nilov V.T. Smolyankin 《The European Physical Journal A - Hadrons and Nuclei》1999,5(4):409-416
New data for the diffractive reaction p+N→ [Σ0
K
+] +N at E
p= 70 GeV were obtained with partially upgraded SPHINX setup. The data are in a good agreement with the results of our previous
study of this reaction. In the mass spectrum M(Σ0
K
+) a structure at the threshold region with a mass ∼1810 MeV and a distinct X(2000) peak with M= 1989 ± 6 MeV and γ= 91 ± 20 MeV are observed. Unusual features of the massive X(2000) state (narrow decay width, anomalously
large branching ratio for the decay channel with strange particle emission) make it a serious candidate for cryptoexotic pentaquark
baryon with hidden strangeness |qqqsˉs>. We also present new results on the narrow threshold structure X(1810) with M= 1807 ± 7 MeV and γ= 62 ± 19 MeV which is produced in the region of very small P
2
T < 0.01 GeV2. The possibility of the Coulomb production mechanism for X(1810) is discussed.
Received: 28 April 1999 相似文献
4.
Burtovoy V. S. Akimenko S. A. Artamonov A. V. Blik A. M. Brekhovskikh V. V. Gorin A. M. Donskov S. V. Inyakin A. V. Kolosov V. N. Kurshetsov V. F. Lishin V. A. Medynsky M. V. Mikhailov Yu. V. Obraztsov V. F. Polyakov V. A. Romanovsky V. I. Rykalin V. I. Sadovsky A. S. Samoilenko V. D. Stenyakin O. V. Uvarov V. A. Filin A. P. Khaustov G. V. Kholodenko S. A. Tchikilev O. G. Yushchenko O. P. Guschin E. N. Duk V. A. Kravtsov V. I. Kudenko Yu. G. Polyarush A. Yu. Filippov S. N. Khudyakov A. A. Bychkov V. N. Zalikhanov B. Zh. Kekelidze G. D. Lysan V. M. 《Journal of Experimental and Theoretical Physics》2020,131(6):928-939
Journal of Experimental and Theoretical Physics - On the statistics of ~1.7 × 108 interactions of positively charged kaons on copper nuclei, coherent events of the K+π0 system production... 相似文献
5.
S. V. Golovkin A. P. Kozhevnikov V. P. Kubarovsky A. I. Kulyavtsev V. F. Kurshetsov L. G. Landsberg V. V. Molchanov V. A. Mukhin I. N. Nikitin V. I. Solyanik D. V. Vavilov V. A. Victorov M. Ya. Balatz G. V. Dzubenko G. S. Lomkatsi V. T. Smolyankin 《Zeitschrift für Physik A Hadrons and Nuclei》1997,359(4):435-444
In the experiments with LEPTON-F and SPHINX spectrometers the pion-induced charged exchange reactions π- + p → ? + n and π- + p → ω + n at Pπ-=32.5 GeV, as well as proton-induced diffractive reactions p + N → [p?] + N and p + N → [pω] + N at E p =70 GeV were studied. The comparison of the cross-sections for ? and ω-production in these reactions is used for testing the OZI selection rule in hadronic processes. It has been demonstrated that in pion reactions the ratio of the yields of ? and ω-mesons R(?/ω) = (3 ± 1) · 10?3 is in a good agreement with naive quark model prediction based on the mixing in vector meson nonet and on the OZI rule (R(?/ω)ozi = tg 2Δθ V ? 4 · 10?3). At the same time in proton reactions the effective ratio of ? and ω yields is ~ (4 ÷ 7) · 10-2, i.e. a strong violation of the OZI rule is observed in proton-nucleon interactions. This violation can be in favor of possible existence of some exotic ss? component in the quark structure of protons. 相似文献
6.
V. F. Kurshetsov Yu. M. Antipov A. V. Artamonov V. A. Batarin O. V. Eroshin V. Z. Kolganov A. S. Konstantinov A. P. Kozhevnikov A. E. Kushnirenko L. G. Landsberg V. M. Leontiev G. S. Lomkatsi V. V. Molchanov V. A. Mukhin A. F. Nilov D. I. Patalakha S. V. Petrenko V. T. Smolyankin D. V. Vavilov V. A. Victorov 《Physics of Atomic Nuclei》2005,68(3):439-454
A search for narrow Θ+(1540), a candidate for a pentaquark baryon with positive strangeness, has been performed in an exclusive proton-induced reaction $p + C(N) \to \Theta ^ + \bar \kappa ^0 + C(N)$ on carbon nuclei or quasifree nucleons at $E_{beam} = 70GeV(\sqrt s = 11.5GeV)$ studying nK +, pK S 0 , and pK L 0 decay channels of Θ+(1540) in four different final states of the $\Theta ^ + \bar K^0 $ system. In order to assess the quality of the identification of the final states with neutron or K L 0 , we reconstructed Λ(1520) → nK S 0 and ? → K L 0 K S 0 decays in the calibration reactions p + C(N) → Λ (1520)K ++C(N) and p+C(N) → p?+C(N). We found no evidence for a narrow pentaquark peak in any of the studied final states and decay channels. Assuming that the production characteristics of the $\Theta ^ + \bar K^0 $ system are not drastically different from those of the Λ(1520)K + and p? systems, we established upper limits on the cross-section ratios $\sigma (\Theta ^ + \bar K^0 )/\sigma (\Lambda (1520)K^ + ) < 0.02$ and $\sigma (\Theta ^ + \bar K^0 )/\sigma (p\phi ) < 0.15$ at 90% C.L. and a preliminary upper limit for the forward-hemisphere cross section $\sigma (\Theta ^ + \bar K^0 )$ nb/nucleon. 相似文献
7.
M. Ya. Balatz I. M. Belyaev V. A. Dorofeev G. B. Dzubenko I. M. Filimonov S. V. Frolov S. V. Golovkin Yu. L. Grishkin M. V. Gritzuk A. D. Kamenskii G. K. Kliger A. P. Kozevnikov V. Z. Kolganov A. S. Konstantinov Yu. V. Korchagin V. P. Kubarovskii N. Yu. Kulman A. I. Kulyavtsev V. F. Kurshetsov A. E. Kushnirenko V. S. Lakaev L. G. Landsberg G. S. Lomkatzi V. V. Molchanov V. A. Mukhin A. P. Nilov Yu. B. Novoghilov V. A. Prutskoi A. I. Sitnikov V. T. Smolyankin V. I. Solyanik D. V. Vavilov V. A. Victorov V. E. Vishnyakov 《Zeitschrift fur Physik C Particles and Fields》1994,61(3):399-405
In the experiments at the SPHINX facility in the 70 GeV proton beam of the IHEP accelerator the diffractive production reactionsp+N[(1385)0
K
+] +N andp+N[(1385)0
K
+]+N+ (neutral particles) were studied. In the effective mass spectra of the [(1385)0
K
+] system in these processes there were no signals from the anomalously narrow baryon stateN
(1960) which had been observed earlier in the measurement at the BIS-2 setup.SPHINX Collaboration (IHEP-ITEP) 相似文献
8.
D. V. Vavilov Yu. M. Antipov A. V. Artamonov V. A. Batarin V. A. Victorov S. V. Golovkin Yu. P. Gorin O. V. Eroshin A. P. Kozhevnikov V. Z. Kolganov A. S. Konstantinov V. P. Kubarovsky V. F. Kurshetsov L. G. Landsberg V. M. Leontiev G. S. Lomkatsi V. V. Molchanov V. A. Mukhin A. F. Nilov D. I. Patalakha S. V. Petrenko A. I. Petrukhin V. T. Smolyankin 《Physics of Atomic Nuclei》2005,68(3):378-384
The radiative decay Λ(1520) → Λγ was recorded in the exclusive reaction p + N → Λ(1520)K + + N at the SPHINX facility. The branching ratio for this decay and the corresponding partial width were found to be, respectively, Br[Λ(1520) → Λγ] = (1.02 ± 0.21) × 10?2 and Γ[Λ(1520) → Λγ] = 159 ± 35 keV (the quoted errors are purely statistical, the systematic errors being within 15%). 相似文献
9.
Kushnirenko A Alkhazov G Atamantchouk AG Balatz MY Bondar NF Cooper PS Dauwe LJ Davidenko GV Dersch U Dolgolenko AG Dzyubenko GB Edelstein R Emediato L Endler AM Engelfried J Eschrich I Escobar CO Evdokimov AV Filimonov IS Garcia FG Gaspero M Giller I Golovtsov VL Gouffon P Gülmez E Kangling H Iori M Jun SY Kaya M Kilmer J Kim VT Kochenda LM Konorov I Kozhevnikov AP Krivshich AG Krüger H Kubantsev MA Kubarovsky VP Kulyavtsev AI Kuropatkin NP Kurshetsov VF Kwan S Lach J Lamberto A Landsberg LG 《Physical review letters》2001,86(23):5243-5246
We report new precision measurements of the lifetimes of the Lambda(+)(c) and D0 from SELEX, the charm hadroproduction experiment at Fermilab. Based upon 1630 Lambda(+)(c) and 10 210 D0 decays we observe lifetimes of tau[Lambda(+)(c)] = 198.1+/-7.0+/-5.6 fs and tau[D0] = 407.9+/-6.0+/-4.3 fs. 相似文献
10.
E. N. Gushchin V. F. Kurshetsov V. A. Lebedev V. I. Romanovskiy V. K. Semenov S. N. Filippov A. A. Khudyakov 《Physics of Atomic Nuclei》2011,74(5):783-787
The matrix hodoscope of the OKA experimental setup and a prototype of the hodoscope for the NA62 experiment are described.
The design of both hodoscopes is presented. The requirements for the hodoscope prototype are listed, and the efficiency and
the time resolution obtained on the basis of experimental data are quoted. 相似文献