# Physical Review Letters (APS)

 2019-03-1518:16 Evidence of a Resonant Structure in the ${e}^{+}{e}^{-}\to {\pi }^{+}{D}^{0}{D}^{*-}$ Cross Section between 4.05 and 4.60 GeV / Ablikim, M. ; Achasov, M. N. ; Ahmed, S. ; Albrecht, M. ; et al The cross section of the process ${e}^{+}{e}^{-}\to {\pi }^{+}{D}^{0}{D}^{*-}$ 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. [...] Published in Physical Review Letters 122 (2019) 10.1103/PhysRevLett.122.102002 2019-03-1322:16 Primordial Black Holes from the QCD Axion / Ferrer, Francesc ; Masso, Eduard ; Panico, Giuliano ; Pujolas, Oriol ; et al We propose a mechanism to generate primordial black holes (PBHs) that is independent of cosmological inflation and occurs slightly below the QCD phase transition. [...] Published in Physical Review Letters 122 (2019) 10.1103/PhysRevLett.122.101301 Fulltext: XML PDF; 2019-03-1318:16 Thermal Emission from Semiclassical Dynamical Systems / Morita, Takeshi Recently the bound on the Lyapunov exponent ${\lambda }_{L}\le 2\pi T/\hslash$ in thermal quantum systems was conjectured by Maldacena, Shenker, and Stanford. [...] Published in Physical Review Letters 122 (2019) 10.1103/PhysRevLett.122.101603 Fulltext: PDF XML; 2019-03-1122:16 Spinor-Helicity Formalism for Massless Fields in ${\mathrm{AdS}}_{4}$ / Nagaraj, Balakrishnan ; Ponomarev, Dmitry In this Letter, we suggest a natural spinor-helicity formalism for massless fields in four-dimensional anti–de Sitter space (${\mathrm{AdS}}_{4}$). [...] Published in Physical Review Letters 122 (2019) 10.1103/PhysRevLett.122.101602 arXiv:1811.08438 Fulltext: XML PDF; 2019-03-1118:16 Polarized Scattering Equations for 6D Superamplitudes / Geyer, Yvonne ; Mason, Lionel We introduce a spinorial version of the scattering equations, the polarized scattering equations, that incorporates spinor polarization data. [...] Published in Physical Review Letters 122 (2019) 10.1103/PhysRevLett.122.101601 arXiv:1812.05548 Fulltext: PDF XML; 2019-03-0116:46 First Measurement of a Long-Lived ${\pi }^{+}{\pi }^{-}$ Atom Lifetime / Adeva, B. ; Afanasyev, L. ; Anania, A. ; Aogaki, S. ; et al The adapted DIRAC experiment at the CERN PS accelerator observed for the first time long-lived hydrogenlike ${\pi }^{+}{\pi }^{-}$ atoms, produced by protons hitting a beryllium target. [...] Published in Physical Review Letters 122 (2019) 10.1103/PhysRevLett.122.082003 arXiv:1811.08659 Fulltext: XML PDF; 2019-03-0116:44 Search for Narrow $H\gamma$ Resonances in Proton-Proton Collisions at $\sqrt{s}=13\text{}\text{}\mathrm{TeV}$ / Sirunyan, A. M. ; Tumasyan, A. ; Adam, W. ; Ambrogi, F. ; et al A search for heavy, narrow resonances decaying to a Higgs boson and a photon ($H\gamma$) has been performed in proton-proton collision data at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of $35.9\text{}\text{}{\mathrm{fb}}^{-1}$ collected with the CMS detector at the LHC in 2016. [...] Published in Physical Review Letters 122 (2019) 10.1103/PhysRevLett.122.081804 arXiv:1808.01257 Fulltext: XML PDF; 2019-03-0116:44 Gravitational Mass Carried by Sound Waves / Esposito, Angelo ; Krichevsky, Rafael ; Nicolis, Alberto We show that the commonly accepted statement that sound waves do not transport mass is only true at linear order. [...] Published in Physical Review Letters 122 (2019) 10.1103/PhysRevLett.122.084501 arXiv:1807.08771 Fulltext: XML PDF; 2019-02-2802:19 Neutrino Masses from Planck-Scale Lepton Number Breaking / Ibarra, Alejandro ; Strobl, Patrick ; Toma, Takashi We consider an extension of the standard model by right-handed neutrinos and we argue that, under plausible assumptions, a neutrino mass of $O\left(0.1\right)\text{}\text{}\mathrm{eV}$ is naturally generated by the breaking of the lepton number at the Planck scale, possibly by gravitational effects, without the necessity of introducing new mass scales in the model. [...] Published in Physical Review Letters 122 (2019) 10.1103/PhysRevLett.122.081803 arXiv:1802.09997 Fulltext: PDF XML; 2019-02-2802:19 Observation of the Decay ${D}^{0}\to {K}^{-}{\pi }^{+}{e}^{+}{e}^{-}$ / Lees, J. P. ; Poireau, V. ; Tisserand, V. ; Grauges, E. ; et al We report the observation of the rare charm decay ${D}^{0}\to {K}^{-}{\pi }^{+}{e}^{+}{e}^{-}$, based on $468\text{}\text{}{\mathrm{fb}}^{-1}$ of ${e}^{+}{e}^{-}$ annihilation data collected at or close to the center-of-mass energy of the $\Upsilon \left(4S\right)$ resonance with the BABAR detector at the SLAC National Accelerator Laboratory. [...] Published in Physical Review Letters 122 (2019) 10.1103/PhysRevLett.122.081802 arXiv:1808.09680 Fulltext: XML PDF;