<p>The KM3NeT experiment has recently observed a neutrino with an energy around 100 PeV, and IceCube has detected five neutrinos with energies above 1 PeV. While there are no known astrophysical sources, exploding primordial black holes could have produced these high-energy neutrinos. For Schwarzschild black holes this interpretation results in tensions between the burst rates inferred from the KM3NeT and IceCube observations, with indirect constraints from the extragalactic gamma-ray background and with the nonobservation of an associated gamma-ray signal at LHAASO. In this Letter we show that if there is a population of primordial black holes charged under a new dark <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>u</mi><mo stretchy="false">(</mo><mn>1</mn><mo stretchy="false">)</mo></math> symmetry which spend most of their time in a quasiextremal state, the neutrino emission at 1 PeV may be more suppressed than at 100 PeV. The burst rates implied by the KM3NeT and IceCube observations and the indirect constraints can then all be consistent at <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>1</mn><mi>σ</mi></math>, and no associated gamma-ray signal was expected at LHAASO. Furthermore, these black holes could constitute all of the observed dark matter in the universe.</p>

United States

Michael J. Baker

Joaquim Iguaz Juan

Aidan Symons

Andrea Thamm

Explaining the PeV Neutrino Fluxes at KM3NeT and IceCube with Quasiextremal Primordial Black Holes

<p>Observation of gamma rays from an exploding black hole would provide strong evidence for primordial black holes, the first direct evidence of Hawking radiation, and definitive information on the particles present in nature. However, indirect constraints suggest that direct observation of an exploding Schwarzschild black hole at current or upcoming gamma ray observatories is implausible. We introduce a dark-QED toy model consisting of a dark photon and a heavy dark electron. In this scenario a population of light primordial black holes charged under the dark <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>u</mi><mo stretchy="false">(</mo><mn>1</mn><mo stretchy="false">)</mo></math> symmetry can become quasiextremal, so they survive much longer than if they were uncharged, before discharging and exhibiting a Schwarzschild-like final explosion. We show that the answer is “yes,” in this scenario the probability of observing an exploding black hole over the next 10 years could potentially be over 90%.</p>

Could We Observe an Exploding Black Hole in the Near Future?

The constituent quark model is used to compute the ground and excited state masses of QQQbaryons containing either c or bquarks. The quark model parameters previously used to describe the properties of charmonium and bottomonium states were used in this analysis. The non-relativistic three-body bound state problem is solved by means of the Gaussian expansion method which provides sufficient accuracy and simplifies the subsequent evaluation of the matrix elements. Several low-lying states with quantum numbers 
					 and 
					 are reported. We compare the results with those obtained by the other theoretical formalisms. There is a general agreement for the mass of the ground state in each sector of triply heavy baryons. However, the situation is more puzzling for the excited states, and appropriate comments about the most relevant features of our comparison are given.
				

China

Gang Yang

Jialun Ping

Spain

Pablo G. Ortega

Jorge Segovia

Triply heavy baryons in the constituent quark model Supported by China Postdoctoral Science Foundation (2019M650617), National Natural Science Foundation of China (11535005, 11775118), and by Spanish Ministerio de Economía, Industria y Competitividad under contractsno. FPA2017-86380-P and FPA2016-77177-C2-2-P. P.G.O. acknowledges the financial support from Spanish MINECO's Juan de la Cierva-Incorporación programme, Grant Agreement No. IJCI-2016-28525.