Preliminary measurements of carbon and oxygen energy spectra from the second flight of CREAM

The Cosmic Ray Energetics and Mass (CREAM) experiment was successfully flown twice on long-duration balloons from McMurdo, Antarctica, in 2004/05 and 2005/06. During the second flight, the redundant charge identification system of the instrument (based on scintillators and silicon detectors) was upgraded with the addition of a second layer of pixelated silicon sensors. A measurement of the particle energy was provided by an ionization calorimeter. From the on-going analysis of the data of the second flight, preliminary results on Carbon and Oxygen spectra up to a few TeV/n will be presented

Relative abundance of heavy ions measured by the CREAM Silicon Charge Detector

The Cosmic Ray Energetics And Mass (CREAM) is a balloon-borne experiment designed for direct measurement of high energy cosmic rays with energy up to 10^15 eV. CREAM incorporates a sampling tungsten/scintillating-fiber calorimeter for energy measurements and a dual-layer Silicon Charge Detector (SCD) and Timing-based Charge Detector (TCD) to measure the charge of incident particles. CREAM has had two successful flights in 2004/5 and 2005/6, with a combined duration of 70 days of data. Preliminary results on the relative abundances of heavy ions measured by the SCD will be presented

The Cosmic Ray Energetics And Mass (CREAM) timing charge detector

The useofdetectorsbasedonplasticscintillatorwithphotomultipliertubes(PMTs)iscommonin cosmic-rayexperimentstodifferentiateparticlecharges.However,inthepresenceofacalorimeter,the standardmethodofpulsechargeintegrationoveratimelongerthanaPMTpulseishamperedby abundantalbedoparticles.TheCosmicRayEnergeticsandMass(CREAM)instrumentsurmountsthis problem bymeasuringthepeakvoltageofthePMTpulsewithin 3 nsofathresholdcrossinginthe readout ofatimingchargedetector(TCD).ThedesignandperformanceoftheTCDispresented. A chargeresolutionof 0.2e for oxygenand0:4e for ironisobtainedforthrough-goingcosmic-ray particles

Elemental Spectra from the CREAM-I flight

The Cosmic Ray Energetics And Mass (CREAM) instrument is a balloon-borne experiment designed to measure the composition and energy spectra of cosmic rays of charge Z = 1 to 26 up to an energy of ~ 10^15 eV. CREAM had two successful flights on long-duration balloons (LDB) launched from McMurdo Station, Antarctica, in December 2004 (CREAM-I) and December 2005. CREAM-I achieves a substantial measurement redundancy by employing multiple detector systems, namely a Timing Charge Detector and a Silicon Charge Detector (SCD) for particle identification, and a Transition Radiation Detector and a sampling tungsten/scintillating-fiber ionization calorimeter (CAL) for energy measurement. In this paper, spectra of various elements measured with SCD/CAL during the first 42-day flight are presented, along with spectral shapes and relative abundances

H and He spectra from the 2004/05 CREAM-I flight

The balloon-borne Cosmic Ray Energetics And Mass (CREAM) payload flew for a record-breaking 42 days during the 2004/05 Antarctic season. The instrument incorporates a tungsten/scintillating-fiber sampling calorimeter and graphite targets to measure energies of nuclei. A finely segmented Silicon Charge detector (SCD) located above the targets is used for charge measurements. The position of the primary particle in the SCD is determined by backward extrapolation of the reconstructed shower axis in the calorimeter. The flight data have been analyzed using the latest calibration of the calorimeter. The energy spectra of proton, helium and their ratios will be presented in this paper

Elemental Spectra from the CREAM-I Flight

The Cosmic Ray Energetics And Mass (CREAM) is a balloon-borne experiment designed to measure the composition and energy spectra of cosmic rays of charge Z = 1 to 26 up to an energy of ~ 10^15 eV. CREAM had two successful flights on long-duration balloons (LDB) launched from Mc- Murdo Station, Antarctica, in December 2004 and December 2005. CREAM-I achieves a substantial measurement redundancy by employing multiple detector systems, namely a Timing Charge Detector and a Silicon Charge Detector (SCD) for particle identification, and a Transition Radiation Detector and a sampling tungsten/scintillating-fiber ionization calorimeter (CAL) for energy measurement. In this paper, preliminary energy spectra of various elements measured with CAL/SCD during the first 42-day flight are presented.The Cosmic Ray Energetics And Mass (CREAM) is a balloon-borne experiment designed to measure the composition and energy spectra of cosmic rays of charge Z = 1 to 26 up to an energy of ~ 10^15 eV. CREAM had two successful flights on long-duration balloons (LDB) launched from Mc- Murdo Station, Antarctica, in December 2004 and December 2005. CREAM-I achieves a substantial measurement redundancy by employing multiple detector systems, namely a Timing Charge Detector and a Silicon Charge Detector (SCD) for particle identification, and a Transition Radiation Detector and a sampling tungsten/scintillating-fiber ionization calorimeter (CAL) for energy measurement. In this paper, preliminary energy spectra of various elements measured with CAL/SCD during the first 42-day flight are presented.The use of detectors based on plastic scintillator with photomultiplier tubes (PMTs) is common in cosmic-ray experiments to differentiate particle charges. However, in the presence of a calorimeter, the standard method of pulse charge integration over a time longer than a PMT pulse is hampered by abundant albedo particles. The Cosmic Ray Energetics and Mass (CREAM) instrument surmounts this problem by measuring the peak voltage of the PMT pulse within ~3ns of a threshold crossing in the readout of a timing charge detector (TCD). The design and performance of the TCD is presented. A charge resolution of 0.2e for oxygen and 0.4e for iron is obtained for through-going cosmic-ray particles

Timing charge and position analysis from the first CREAM flight

The first flight of the Cosmic Ray Energetics And Mass (CREAM) balloon experiment employed a Timing Charge Detector (TCD) and a Calorimeter. For high energy events a large background of back splash particles are created in the Calorimeter, which wash out the low Z charge peaks in the TCD. Traditionally, highly pixelated detectors are used in this situation in order to reduce the effects of the background. However, CREAM employed ultra fast photomultipliers and electronics in order to measure the rise time of the charge peak, which should be proportional to the amplitude of the charge peak and provide the charge of low Z cosmic rays when the peak detectors are saturated. These fast detectors also provide useful lateral tracking information along the direction of the scintillation paddle. These analysis techniques will be presented