Improved measurement of electron antineutrino disappearance at Daya Bay

We report an improved measurement of the neutrino mixing angle θ13 from the Daya Bay Reactor Neutrino Experiment. We exclude a zero value for sin22θ13 with a significance of 7.7 standard deviations. Electron antineutrinos from six reactors of 2.9 GWm th were detected in six antineutrino detectors deployed in two near （flux-weighted baselines of 470 m and 576 m） and one far （1648 m） underground experimental halls. Using 139 days of data, 28909 （205308） electron antineutrino candidates were detected at the far hall （near halls）. The ratio of the observed to the expected number of antineutrinos assuming no oscillations at the far hall is 0.944± 0.007（stat.） ± 0.003（syst.）. An analysis of the relative rates in six detectors finds sin22θ13=0.089± 0.010（stat.）±0.005（syst.） in a three-neutrino framework.

BOTTOM MESONS(B=±1)B^+=u,B^0=d,B^0=db,B^-=b,similarly for B~*'s

Many measurements of B decays involve admixtures of B hadrons. Previously we arbitrarily included such admixtures in the B±section, but because of their importance we have created two new sections：

N BARYONS(S=0,I=1/2)p,N^+=uud;n,N^0=udd

p MASS （atomic mass units u）The mass is known much more precisely in u （atomic mass units） than in MeV. See the next data block.

BOTTOM,CHARMED MESONS(B=C=±1)B_c^+=c,B_c^-=cb,similarly for B_c~*'s

I（JP） = 0（0-）I, J, P need confirmation.Quantum numbers shown are quark-model predictions.

REVIEW OF PARTICLE PHYSICS

The Review summarizes much of particle physics and cosmology. Using data from previous editions, plus 3,283 new measurements from 899 papers, we list, evaluate, and average measured properties of gauge bosons and the recently discovered Higgs boson, leptons, quarks, mesons, and baryons. We summarize searches for hypothetical particles such as heavy neutrinos, supersymmetric and technicolor particles, axions, dark photons, etc. All the particle properties and search limits are listed in Summary Tables. We also give numerous tables, figures, formulae, and reviews of topics such as Supersymmetry, Extra Dimensions, Particle Detectors, Probability, and Statistics. Among the 112 reviews are many that are new or heavily revised including those on： Dark Energy, Higgs Boson Physics, Electroweak Model, Neutrino Cross Section Measurements, Monte Carlo Neutrino Generators, Top Quark, Dark Matter, Dynamical Electroweak Symmetry Breaking, Accelerator Physics of Colliders, High-Energy Collider Parameters, Big Bang Nucleosynthesis, Astrophysical Constants and Cosmological Parameters. A booklet is available containing the Summary Tables and abbreviated versions of some of the other sections of this full Review. All tables, listings, and reviews （and errata） are also available on the Particle Data Group website： http ：//pdg. lbl. gov.

Improved measurement of the reactor antineutrino flux and spectrum at Daya Bay

A new measurement of the reactor antineutrino flux and energy spectrum by the Daya Bay reactor neutrino experiment is reported. The antineutrinos were generated by six 2.9 GWth nuclear reactors and detected by eight antineutrino detectors deployed in two near（560 m and 600 m flux-weighted baselines） and one far（1640 m flux-weighted baseline） underground experimental halls. With 621 days of data, more than 1.2 million inverse beta decay（IBD） candidates were detected. The IBD yield in the eight detectors was measured, and the ratio of measured to predicted flux was found to be 0.946±0.020（0.992±0.021） for the Huber＋Mueller（ILL＋Vogel） model. A 2.9σ deviation was found in the measured IBD positron energy spectrum compared to the predictions. In particular, an excess of events in the region of 4–6 MeV was found in the measured spectrum, with a local significance of 4.4σ. A reactor antineutrino spectrum weighted by the IBD cross section is extracted for model-independent predictions.

CHARMED BARYONS(C=+1)∧_c^+=udc,∑_c^(++)=uuc,∑_c^+=udc,∑_c^0=ddc,≡_c^+=usc,≡_c^0=dsc,Ω_c^0=ssc

CHARMED BARYONS Revised March 2012 by C.G. Wohl （LBNL）. There are 17 known charmed baryons, and four other candidates not well enough established to be promoted to the Summary Tables.＊ Fig. l（a） shows the mass spectrum,

PARTICLE DETECTORS AT ACCELERATORS

33.1. Introduction This review summarizes the detector technologies employed at accelerator particle physics experiments. Several of these detectors are also used in a non-accelerator context and examples of such applications will be provided. The detector techniques which are specific to non-accelerator particle physics experiments are the subject of Chap.

INTRODUCTION

1. Overview The Review of Particle Physics and the abbreviated version, the Particle Physics Booklet, are reviews of the field of Particle Physics. This complete Review includes a compilation/evaluation of data on particle properties, called the ＂Particle Listings.＂ These Listings include 3,283 new measurements from 899 papers, in addition to the 32,153 measurements from 8,944 papers that first appeared in previous editions [1].

BOTTOM BARYONS(B=-1)∧_b^0=udb,≡_b^0=usb,≡_b^-=dsb,Ω_b^-=ssb

In the quark model, a ∧b0 is an isospin-0 udb state. The lowest ∧b0 ought to have JP = 1/2＋. None of I, J, or P have actually been measured.

∧ BARYONS(S=-1,I=0)∧~0=uds

We have omitted some results that have been superseded by later experiments. See our earlier editions.

Search for electron-antineutrinos associated with gravitational-wave events GW150914,GW151012,GW151226,GW170104,GW170608,GW170814,and GW170817 at Daya Bay

The establishment of a possible connection between neutrino emission and gravitational-wave(GW)bursts is important to our understanding of the physical processes that occur when black holes or neutron stars merge.In the Daya Bay experiment,using the data collected from December 2011 to August 2017,a search was per-formed for electron-antineutrino signals that coincided with detected GW events,including GW150914,GW151012,GW151226,GW170104,GW170608,GW 170814,and GW 170817.We used three time windows of±10,±500,and±1000 s relative to the occurrence of the GW events and a neutrino energy range of 1.8 to 100 MeV to search for correlated neutrino candidates.The detected electron-antineutrino candidates were consistent with the expected background rates for all the three time windows.Assuming monochromatic spectra,we found upper limits(90%confidence level)of the electron-antineutrino fluence of(1.13-2.44)×10^(11)cm^(-2)at 5 MeV to 8.0×10^(7)cm^(-2)at 100 MeV for the three time w indows.Under the assumption of a Fermi-Dirac spectrum,the upper limits were found to be(5.4-7.0)×10^(9)cm^(2)for the three time windows.

SU(3) ISOSCALAR FACTORS AND REPRESENTATION MATRICES

Written by R.L. Kelly （LBNL）. The most commonly used SU（3） isoscalar factors, corresponding to the singlet, octet, and deeuplet content of 8 8 and 10 8, are shown at the right. The notation uses particle names to identify the coefficients, so that the pattern of relative couplings may be seen at a glance. We illustrate the use of the coefficients below.

QUARKS

QUARK MASSESUpdated Jan 2014 by A.V. Manohar （University of California, San Diego） and C.T. Sachrajda （University of Southampton）

ELECTROWEAK MODEL AND CONSTRAINTS ON NEW PHYSICS

Revised November 2013 by J. Erler （U. Mexico） and A. Freit＆s （Pittsburgh U.）.10.1 Introduction 10.2 Renormalization and radiative corrections

ACCELERATOR PHYSICS OF COLLIDERS

Revised August 2013 by M.J. Syphers （MSU） and F. Zimmermann （CERN）.29.1. Luminosity This article provides background for the High-Energy Collider Parameter Tables that follow. The number of events, Nexp, is the product of the cross section of interest,

CLEBSCH-GORDAN COEFFICIENTS,SPHERICAL HARMONICS,AND d FUNCTIONS

Note： A square-root sign is to be understood over every coefficient, e.g., for -8/15 read - √8√15.

KINEMATICS

Revised January 2000 by J.D. Jackson （LBNL） and June 2008 by D.R. Tovey （Sheffield）.

QUARK MODEL

Revised August 2013 by C. Amsler （University of Bern）, T. DeGrand （University of Colorado, Boulder）, and B. Krusche （University of Basel）.

BIG-BANG COSMOLOGY

Revised September 2013 by K.A. Olive （University of Minnesota） and J.A. Peacock （University of Edinburgh）.