Пахлова Галина Владимировна
Московский институт электроники и математики им. А.Н. Тихонова
Профессиональные интересы
Должности
- Ведущий научный сотрудник — Московский институт электроники и математики им. А.Н. Тихонова, Международная лаборатория физики элементарных частиц
Био
- · Начала работать в НИУ ВШЭ в 2020 году.
- · Научно-педагогический стаж: 4 года.
Образование
- 2011 · Доктор физико-математических наук: Высшая аттестационная комиссия Республика Болгария
- 1994 · Кандидат физико-математических наук: Институт теоретической и экспериментальной физики
- 1984 · Специалитет: Московский инженерно-физический институт, специальность «Экспериментальная ядерная физика», квалификация «Инженер-физик»
Идентификаторы исследователя
- ORCID:
0000-0001-7518-3022 - ResearcherID:
C-5378-2014 - SPIN РИНЦ:
1406-3272 - Google Scholar: https://scholar.google.com/citations?view_op=list_works&hl=en&user=fFiMLk0AAAAJ&gmla=AJsN-F7mn-IyCnEj_Ug1RmF450uvfNhIP59Uxymi_BKjMGYOUB8KunCrnueLqUiIeo_gIyW4wBX8b-M5m79_triQ4PcDP35zFxATkp5JZ_5okKDfZW6pyWs
- Scopus AuthorID:
35234620700
Публикации (189)
Search for transitions from Υ(4S) and Υ(5S) to ηb(1S) and ηb(2S) with emission of an ω meson
2020 в печати · ARTICLE · en
Using data collected in the Belle experiment at the KEKB asymmetric-energy e+e− collider we search for transitions Υ(4S)→ηb(1S)ω, Υ(5S)→ηb(1S)ω and Υ(5S)→ηb(2S)ω. No significant signals are observed and we set 90\% confidence level upper limits on the corresponding visible cross sections: 0.2 pb,0.4 pb and 1.9 pb, respectively.
Evidence for X(3872)→J/ψπ+π− produced in single-tag two-photon interactions
2020 в печати · ARTICLE · en
We report the first evidence for X(3872) production in two-photon interactions by tagging either the electron or the position in the final state, exploring the highly virtual photon region. The search is performed in e+e−→e+e−J/ψπ+π−, using 825 fb−1 of data collected by the Belle detector operated at the KEKB e+e− collider. We observe three X(3872) candidates with an expected background of 0.11±0.10 events, with a significance of 3.2σ. We obtain an estimated value for Γ~γγB(X(3872)→J/ψπ+π−) assuming the Q2 dependence predicted by a cc¯ meson model, where −Q2 is the invariant mass-squared of the virtual photon. No X(3915)→J/ψπ+π− candidates are found.
Search for a doubly-charged DDK bound state in Υ(1S,2S) inclusive decays and via direct production in e+e− collisions at s√ = 10.520, 10.580, and 10.867 GeV
2020 в печати · ARTICLE · en
We report the results of a first search for a doubly-charged DDK bound state, denoted the R++, in Υ(1S) and Υ(2S) inclusive decays and via direct production in e+e− collisions at s√ = 10.520, 10.580, and 10.867 GeV. The search uses data accumulated with the Belle detector at the KEKB asymmetric-energy e+e− collider. No significant signals are observed in the D+D∗+s invariant-mass spectra of all studied modes. The 90\% credibility level upper limits on their product branching fractions in Υ(1S) and Υ(2S) inclusive decays (B(Υ(1S,2S)→R+++anything)×B(R++→D+D∗+s)), and the product values of Born cross section and branching fraction in e+e− collisions (σ(e+e−→R+++anything)×B(R++→D+D∗+s)) at s√ = 10.520, 10.580, and 10.867 GeV under different assumptions of R++ masses varying from 4.13 to 4.17 GeV/c2, and widths varying from 0 to 5 MeV are obtained.
Search for the B →Y(4260)K, Y(4260) →J/ψπ+π- decays
2019 · ARTICLE · en
We report the results of a search for the B→Y(4260)K, Y(4260)→J/ψπ+π− decays. This study is based on a data sample corresponding to an integrated luminosity of 711~fb−1 , collected at the Υ(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e− collider. We investigate the J/ψπ+π− invariant mass distribution in the range 4.0 to 4.6 GeV/c2 using both B+→J/ψπ+π−K+ and B0→J/ψπ+π−K0S decays. We find excesses of events above the background levels, with a significances of 2.1 and 0.9 standard deviations for charged and neutral B→Y(4260)K decays, respectively, taking into account the systematic uncertainties. These correspond to upper limits on the product of branching fractions, B(B+→Y(4260)K+)×B(Y(4260)→J/ψπ+π−)B0→Y(4260)K0)×B(Y(4260)→J/ψπ+π−)
Measurements of the branching fractions B(B- → Λc-Ξ'c0), B(B- → Λc-Ξc(2645)0) and B(B- → Λc-Ξc(2790)0
2019 · ARTICLE · en
Using the data sample of 711 fb−1 of Υ(4S) on-resonance data taken by the Belle detector at the KEKB asymmetric-energy electron-positron collider, we present the first measurements of branching fractions of the decays B−→Λ¯−cΞ′0c , B−→Λ¯−cΞc(2645)0 , and B−→Λ¯−cΞc(2790)0 . The signal yields for these decays are extracted from the recoil mass spectrum of the system recoiling against Λ¯−c baryons in selected B− candidates. The branching fraction of B−→Λ¯−cΞc(2790)0 is measured to be (1.1±0.4±0.2)×10−3 , where the first uncertainty is statistical and the second systematic. The 90\% credibility level upper limits on B(B−→Λ¯−cΞ′0c) and B(B−→Λ¯−cΞc(2645)0) are determined to be 6.5×10−4 and 7.9×10−4 , respectively.
Observation of a new structure near 10.75 GeV in the energy dependence of the e+e- → ϒ(nS)π+π- (n=1,2,3) cross sections
2019 · ARTICLE · en
We report a new measurement of the e+e−→Υ(nS)π+π− (n=1,2,3) cross sections at energies from 10.52 to 11.02 GeV using data collected with the Belle detector at the KEKB asymmetric-energy e+e− collider. We observe a new structure in the energy dependence of the cross sections; if described by a Breit-Wigner function its mass and width are found to be M=(10752.7±5.9+0.7−1.1)MeV/c2 and Γ=(35.5+17.6−11.3+3.9−3.3)MeV, where the first error is statistical and the second is systematic. The global significance of the new structure including systematic uncertainty is 5.2 standard deviations. We also find evidence for the e+e−→Υ(1S)π+π− process at the energy 10.52 GeV, which is below the BB¯ threshold.
Search for X(3872) and X(3915) decay into chi(c1)pi(0) in B decays at Belle
2019 · ARTICLE · en
We report a search for X(3872) and X(3915) in B+→χc1π0K+ decays. We set an upper limit of B(B+→X(3872)K+)×B(X(3872)→χc1π0) B+→X(3915)K+)×B(X(3915)→χc1π0) X(3872)→χc1π0)/B(X(3872)→J/ψπ+π−)BB¯¯¯¯ events collected at the Υ(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e− collider.
First measurements of absolute branching fractions of the Ξc 0 Baryon at Belle
2019 · ARTICLE · en
We present the first measurements of the absolute branching fractions of Ξ+c decays into Ξ−π+π+ and pK−π+ final states. Our analysis is based on a data set of (772±11)×106 BB¯ pairs collected at the Υ(4S) resonance with the Belle detector at the KEKB e+e− collider. We measure the absolute branching fraction of B¯0→Λ¯−cΞ+c with the Ξ+c recoiling against Λ¯−c in B¯0 decays resulting in B(B¯0→Λ¯−cΞ+c)=[1.16±0.42(stat.)±0.15(syst.)]×10−3 . We then measure the product branching fractions B(B¯0→Λ¯−cΞ+c)B(Ξ+c→Ξ−π+π+) and B(B¯0→Λ¯−cΞ+c)B(Ξ+c→pK−π+) . Dividing these product branching fractions by B¯0→Λ¯−cΞ+c yields: B(Ξ+c→Ξ−π+π+)=[2.86±1.21(stat.)±0.38(syst.)]% and B(Ξ+c→pK−π+)=[0.45±0.21(stat.)±0.07(syst.)]% . Our result for B(Ξ+c→Ξ−π+π+) can be combined with Ξ+c branching fractions measured relative to Ξ+c→Ξ−π+π+ to set the absolute scale for many Ξ+c branching fractions.
Observation of B+ →p Λ ̄ K+K- and B+ → p ̄ Λk+K+
2019 · ARTICLE · en
We report the study of B+→pΛ̄K+K- and B+→p̄ΛK+K+ decays using a 772×106 BB̄ pair data sample recorded on the Ï (4S) resonance with the Belle detector at KEKB. The following branching fractions are measured: B(B+→pΛ̄K+K-)=(4.10-0.43+0.45±0.50)×10-6, B(B+→p̄ΛK+K+)=(3.70-0.37+0.39±0.44)×10-6, B(ηc→pΛ̄K-+c.c.)=(2.83-0.34+0.36±0.35)×10-3 and B(B+→pΛ̄φ)=(7.95±2.09±0.77)×10-7, where c.c. denotes the corresponding charge-conjugation process. The intermediate resonance decays are excluded in the four-body decay measurements. We also find evidence for B(ηc→Λ(1520)Λ̄+c.c.)=(3.48±1.48±0.46)×10-3 and B(B+→Λ(1520)Λ̄K+)=(2.23±0.63±0.25)×10-6. No significant signals are found for J/ψ→Λ(1520)Λ̄+c.c. and B+→Λ̄(1520)ΛK+; we set the 90% confidence level upper limits on their decay branching fractions as
Measurement of time-dependent CP violation in B0 → KS0 π0π0 decays
2019 · ARTICLE · en
We report a measurement of time-dependent CP violation in B0→KS0π0π0 decays using a data sample of 772×106 BB pairs collected by the Belle experiment running at the ?(4S) resonance at the KEKB e+e- collider. This decay proceeds mainly via a b→sdd "penguin" amplitude. The results are sin2φ1eff=0.92-0.31+0.27 (stat.) ±0.11 (syst.) and A=0.28±0.21 (stat.) ±0.04 (syst.), which are the most precise measurements of CP violation in this decay mode to date. The value for the CP-violating parameter sin2φ1eff is consistent with that obtained using decay modes proceeding via a b→ccs "tree" amplitude.
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