A search for the doubly charmed baryon ?cc+with the decay mode ?cc+→Ξc+K-π+is performed using proton-proton collision data at a centre-of-mass energy of 13 TeV collected by the LHCb experiment from 2016 to 2018, co...
A search for the doubly charmed baryon ?cc+with the decay mode ?cc+→Ξc+K-π+is performed using proton-proton collision data at a centre-of-mass energy of 13 TeV collected by the LHCb experiment from 2016 to 2018, corresponding to an integrated luminosity of 5.4 fb-1. No significant signal is observed within the invariant mass range of 3.6 to 4.0 GeV/c2. Upper limits are set on the ratio R of the production cross-section times the total branching fraction of the ?cc+→Ξc+K-π+decay with respect to the Ξcc++→Λc+K-π+π+decay. Upper limits at 95% credibility level for R in the range 0.005 to 0.11 are obtained for diferent hypotheses on the ?cc+mass and lifetime in the rapidity range from 2.0 to 4.5 and transverse momentum range from 4 to 15 GeV/c.
The Circular Electron Positron Collider (CEPC) is a large-scale colliderfacility that can serve as a factory of the Higgs, Z, and W bosons and isupgradable to run at the ttbar threshold. This document describes the la...
Recent studies have theoretically investigated the atomic excitation and ionization induced by the dark matter–nucleus scattering, and it was found that the suddenly recoiled atom is much more likely to excite or los...
详细信息
Recent studies have theoretically investigated the atomic excitation and ionization induced by the dark matter–nucleus scattering, and it was found that the suddenly recoiled atom is much more likely to excite or lose its electrons than expected. This phenomenon is called the “Migdal effect.” In this paper, we extend the established strategy to describe the Migdal effect in isolated atoms to the case in semiconductors under the framework of the tight-binding approximation. Since the localized aspects of electrons are respected in the form of the Wannier functions, the extension of the existing Migdal approach for isolated atoms is much more natural, while the extensive nature of electrons in solids is reflected in the hopping integrals. We take a diamond target as a concrete proof of principle for the methodology, and calculate relevant energy spectra and the projected sensitivity of such a diamond detector. It turns out that our method as a preliminary attempt is theoretically self-consistent and practically effective.
The polarization of τ leptons is measured using leptonic and hadronic τ lepton decays in Z → τ+ τ− events in proton-proton collisions at (Formula presented.) recorded by CMS at the CERN LHC with an integrated lum...
详细信息
The perovskite-type iron oxide Sr2/3La1/3FeO3 is known to show characteristic spin-charge ordering (SCO), where sixfold collinear spin ordering and threefold charge ordering are coupled with each other. Here, we repor...
详细信息
The perovskite-type iron oxide Sr2/3La1/3FeO3 is known to show characteristic spin-charge ordering (SCO), where sixfold collinear spin ordering and threefold charge ordering are coupled with each other. Here, we report the discovery of a spin-charge decoupling and an antiferromagnetic (AFM) state competing with the SCO phase in perovskites (Sr1−xBax)2/3La1/3FeO3. By comprehensive measurements including neutron diffraction, Mössbauer spectroscopy, and x-ray absorption spectroscopy, we found that the isovalent Ba2+ substitution systematically reduces the critical temperature of the SCO phase and additionally yields the spin-charge decoupling in x>0.75. Whereas the ground state remains in the SCO phase in the whole x region, an unexpected G-type AFM phase with incoherent charge ordering or charge fluctuation appears as the high-temperature phase in the range of x>0.75. Reflecting the competing nature between them, the G-type AFM phase partially exists as a metastable state in the SCO phase at low temperatures. We discuss the origin of the spin-charge decoupling and the emergence of the G-type AFM phase with charge fluctuation in terms of the bandwidth reduction by the Ba substitution.
A set of measurements for the production of a $$W$$ -boson in association with high-transverse-momentum jets is presented using 140 fb $$^{-1}$$ of proton–proton collision data at a centre-of-mass energy of ...
A set of measurements for the production of a $$W$$ -boson in association with high-transverse-momentum jets is presented using 140 fb $$^{-1}$$ of proton–proton collision data at a centre-of-mass energy of $$\sqrt{s}=13$$ TeV collected by the ATLAS detector at the LHC. The measurements are performed in final states in which the $$W$$ -boson decays into an electron or muon plus a neutrino and is produced in association with jets with $$p_{\text {T}} {EMPTY}>30$$ GeV, where the leading jet has $$p_{\text {T}} {EMPTY}>500$$ GeV. The angular separation between the lepton and the closest jet with $$p_{\text {T}} {EMPTY}>100$$ GeV is measured and used to define a collinear phase space, wherein measurements of kinematic properties of the $$W$$ -boson and the associated jet are performed. The collinear phase space is populated by dijet events radiating a $$W$$ -boson and events with a $$W$$ -boson produced in association with several jets and it serves as an excellent data sample to probe higher-order theoretical predictions. Measured differential distributions are compared with predictions from state-of-the-art next-to-leading order multi-leg merged Monte Carlo event generators and a fixed-order calculation of the $$W+1$$ -jet process computed at next-to-next-to-leading order in the strong coupling constant.
A measurement of the Higgs boson (H) production via vector boson fusion (VBF) and its decay into a bottom quark-antiquark pair (bb¯) is presented using proton-proton collision data recorded by the CMS experiment ...
详细信息
We have been developing the monolithic active pixel detector "XRPIX" onboard the future X-ray astronomical satellite "FORCE". XRPIX is composed of CMOS pixel circuits, SiO2 insulator, and Si sensor...
详细信息
The spongy mesophyll is a complex, porous tissue found in plant leaves that enables carbon capture and provides mechanical stability. Unlike many other biological tissues, which remain confluent throughout development...
详细信息
暂无评论