Determination of the Pseudoscalar Decay Constant fDs+ via Ds+→μ+νμ

Aerosol optical properties and direct radiative forcing based on measurements from the China Aerosol Remote Sensing Network (CARSNET) in eastern China

Aerosol pollution in eastern China is an unfortunate consequence of the region's rapid economic and industrial growth. Here, sun photometer measurements from seven sites in the Yangtze River Delta (YRD) from 2011 to 2015 were used to characterize the climatology of aerosol microphysical and optical properties, calculate direct aerosol radiative forcing (DARF) and classify the aerosols based on size and absorption. Bimodal size distributions were found throughout the year, but larger volumes and effective radii of fine-mode particles occurred in June and September due to hygroscopic growth and/or cloud processing. Increases in the fine-mode particles in June and September caused AOD440 nm  &…

First measurement of e+e−→pKS0n¯K−+c.c. above open charm threshold

The process e(+)e(-) -> pK(S)(0)(n) over barK(-) + c.c. and its intermediate processes are studied for the first time, using data samples collected with the BESIII detector at BEPCII at center-o ...

Measurement of the Dynamics of the Decays Ds+→η(′)e+νe

PubMed ID: 30978074

Evidence of a Resonant Structure in the Cross Section between 4.05 and 4.60 GeV

The cross section of the process e^{+}e^{-}→π^{+}D^{0}D^{*-} for center-of-mass energies from 4.05 to 4.60 GeV is measured precisely using data samples collected with the BESIII detector operating at the BEPCII storage ring. Two enhancements are clearly visible in the cross section around 4.23 and 4.40 GeV. Using several models to describe the dressed cross section yields stable parameters for the first enhancement, which has a mass of 4228.6±4.1±6.3  MeV/c^{2} and a width of 77.0±6.8±6.3  MeV, where the first uncertainties are statistical and the second ones are systematic. Our resonant mass is consistent with previous observations of the Y(4220) state and the theoretical prediction of a D…

Determination of the Pseudoscalar Decay Constant fDs+ via Ds+→μ+νμ

Using a 3.19  fb^{-1} data sample collected at an e^{+}e^{-} center-of-mass energy of E_{cm}=4.178  GeV with the BESIII detector, we measure the branching fraction of the leptonic decay D_{s}^{+}→μ^{+}ν_{μ} to be B_{D_{s}^{+}→μ^{+}ν_{μ}}=(5.49±0.16_{stat}±0.15_{syst})×10^{-3}. Combining our branching fraction with the masses of the D_{s}^{+} and μ^{+} and the lifetime of the D_{s}^{+}, we determine f_{D_{s}^{+}}|V_{cs}|=246.2±3.6_{stat}±3.5_{syst}  MeV. Using the c→s quark mixing matrix element |V_{cs}| determined from a global standard model fit, we evaluate the D_{s}^{+} decay constant f_{D_{s}^{+}}=252.9±3.7_{stat}±3.6_{syst}  MeV. Alternatively, using the value of f_{D_{s}^{+}} calculat…

Measurement of the Absolute Branching Fraction of the Inclusive Decay Λc+ → Λ+X

Physical review letters 121(6), 062003 (2018). doi:10.1103/PhysRevLett.121.062003

Precision Measurement of the Branching Fractions of η′ Decays

PubMed ID: 31050481

Measurement of e+ e- → DD cross sections at the ψ(3770) resonance

Chinese physics / C High energy physics and nuclear physics C 42(8), 083001 (2018). doi:10.1088/1674-1137/42/8/083001

Column aerosol optical properties and aerosol radiative forcing during a serious haze-fog month over North China Plain in 2013 based on ground-based sunphotometer measurements

In January 2013, North China Plain experienced several serious haze events. Cimel sunphotometer measurements at seven sites over rural, suburban and urban regions of North China Plain from 1 to 30 January 2013 were used to further our understanding of spatial-temporal variation of aerosol optical parameters and aerosol radiative forcing (ARF). It was found that Aerosol Optical Depth at 500 nm (AOD500 nm) during non-pollution periods at all stations was lower than 0.30 and increased significantly to greater than 1.00 as pollution events developed. The Angstrom exponent (Alpha) was larger than 0.80 for all stations most of the time. AOD500 nm averages increased from north to south during both…

Evidence for the decays of and *

Abstract We study the hadronic decays of to the final states and , using an annihilation data sample of 567 pb-1 taken at a center-of-mass energy of 4.6 GeV with the BESIII detector at the BEPCII collider. We find evidence for the decays and with statistical significance of and , respectively. Normalizing to the reference decays and , we obtain the ratios of the branching fractions and to be and , respectively. The upper limits at the 90% confidence level are set to be and . Using BESIII measurements of the branching fractions of the reference decays, we determine % (<0.68%) and % (<1.9%). Here, the first uncertainties are statistical and the second systematic. The obtained branching …

Observation of D+→f0(500)e+νe and Improved Measurements of D→ρe+νe

Using a data sample corresponding to an integrated luminosity of 2.93 fb(-1) recorded by the BESIII detector at a center-of-mass energy of 3.773 GeV, we present an analysis of the decays D-0 -> ...

Spatial distribution of aerosol microphysical and optical properties and direct radiative effect from the China Aerosol Remote Sensing Network

Multi-year observations of aerosol microphysical and optical properties, obtained through ground-based remote sensing at 50 China Aerosol Remote Sensing Network (CARSNET) sites, were used to characterize the aerosol climatology for representative remote, rural, and urban areas over China to assess effects on climate. The annual mean effective radii for total particles (ReffT) decreased from north to south and from rural to urban sites, and high total particle volumes were found at the urban sites. The aerosol optical depth at 440 nm (AOD440 nm) increased from remote and rural sites (0.12) to urban sites (0.79), and the extinction Ångström exponent (EAE440–870 nm) increased fro…

First Measurement of the Form Factors in Ds+→K0e+νe and Ds+→K*0e+νe Decays

We report on new measurements of Cabibbo-suppressed semileptonic D_{s}^{+} decays using 3.19  fb^{-1} of e^{+}e^{-} annihilation data sample collected at a center-of-mass energy of 4.178 GeV with the BESIII detector at the BEPCII collider. Our results include branching fractions B(D_{s}^{+}→K^{0}e^{+}ν_{e})=[3.25±0.38(stat)±0.16(syst)]×10^{-3} and B(D_{s}^{+}→K^{*0}e^{+}ν_{e})=[2.37±0.26(stat)±0.20(syst)]×10^{-3}, which are much improved relative to previous measurements, and the first measurements of the hadronic form-factor parameters for these decays. For D_{s}^{+}→K^{0}e^{+}ν_{e}, we obtain f_{+}(0)=0.720±0.084(stat)±0.013(syst), and for D_{s}^{+}→K^{*0}e^{+}ν_{e}, we find form-factor r…

Measurement of the phase between strong and electromagnetic amplitudes of J/ψ decays

Kolcu, Onur Buğra (Arel Author)