Status and recent results from the cream experiment

The Cosmic Ray Energetics And Mass (CREAM) balloon-borne experiment has accumulated ∼156 days of exposure during five successful flights over Antarctica. Energy measurements are made with a transition radiation detector and an ionization calorimeter. Charge measurements are made with timing scintillators, pixelated Si, and Cherenkov detectors to minimize the effect of backscattered particles. High energy cosmic-ray data were collected over a wide energy range from ∼ 10¹⁰ to ∼ 10¹⁵ eV at an average altitude of ∼38.5 km, with ∼3.9 g/cm² atmospheric overburden. All cosmic-ray elements from protons (Z = 1) to iron nuclei (Z = 26) are separated with excellent charge resolution. The instrument performance, results from the ongoing data analysis, and their implications on cosmic-ray origin, acceleration and propagation are discussed.