Isotropy of Cosmic Rays beyond 10

We report an estimation of the injected mass composition of ultrahigh energy cosmic rays (UHECRs) at energies higher than 10 EeV. The composition is inferred from an energy-dependent sky distribution of UHECR events observed by the Telescope Array surface detector by comparing it to the Large Scale Structure of the local Universe. In the case of negligible extragalactic magnetic fields (EGMFs), the results are consistent with a relatively heavy injected composition at E∼10 EeV that becomes lighter up to E∼100 EeV, while the composition at E>100 EeV is very heavy. The latter is true even in the presence of highest experimentally allowed extragalactic magnetic fields, while the composition at lower energies can be light if a strong EGMF is present. The effect of the uncertainty in the galactic magnetic field on these results is subdominant.

An extremely energetic cosmic ray observed by a surface detector array.

Cosmic rays are energetic charged particles from extraterrestrial sources, with the highest-energy events thought to come from extragalactic sources. Their arrival is infrequent, so detection requires instruments with large collecting areas. In this work, we report the detection of an extremely energetic particle recorded by the surface detector array of the Telescope Array experiment. We calculate the particle's energy as [Formula: see text] (~40 joules). Its arrival direction points back to a void in the large-scale structure of the Universe. Possible explanations include a large deflection by the foreground magnetic field, an unidentified source in the local extragalactic neighborhood, or an incomplete knowledge of particle physics.

Indapamide-associated Stevens-Johnson syndrome.

Stevens-Johnson syndrome is an acute, inflammatory eruption of the skin and mucous membranes often associated with drug ingestion. A forty-five-year-old woman showed symptoms consistent with Stevens-Johnson syndrome two days after indapamide therapy was begun for the treatment of hypertension. Initial manifestations consisted of headaches, sore throat, cough, and symptoms of conjunctival injection, including redness and swelling. Approximately two weeks later, the patient noted skin eruptions involving the conjunctiva, lips, face, neck, trunk, and extremities. She was treated with cool compresses, antiseptics, ophthalmic antibiotics and steroids, and oral prednisone. Symptoms began to resolve approximately eight days after indapamide was discontinued and treatment was begun. Although rare, Stevens-Johnson syndrome should be considered in the differential diagnosis of a patient with a history of indapamide ingestion who presents with malaise, fever, and skin eruptions.