27 research outputs found
A Study of Cosmic Ray Secondaries Induced by the Mir Space Station Using AMS-01
The Alpha Magnetic Spectrometer (AMS-02) is a high energy particle physics
experiment that will study cosmic rays in the to range and will be installed on the International Space Station
(ISS) for at least 3 years. A first version of AMS-02, AMS-01, flew aboard the
space shuttle \emph{Discovery} from June 2 to June 12, 1998, and collected
cosmic ray triggers. Part of the \emph{Mir} space station was within the
AMS-01 field of view during the four day \emph{Mir} docking phase of this
flight. We have reconstructed an image of this part of the \emph{Mir} space
station using secondary and emissions from primary cosmic rays
interacting with \emph{Mir}. This is the first time this reconstruction was
performed in AMS-01, and it is important for understanding potential
backgrounds during the 3 year AMS-02 mission.Comment: To be submitted to NIM B Added material requested by referee. Minor
stylistic and grammer change
Cosmic-ray positron fraction measurement from 1 to 30 GeV with AMS-01
A measurement of the cosmic ray positron fraction e+/(e+ + e-) in the energy range of 1-30 GeV is presented. The measurement is based on data taken by the AMS-01 experiment during its 10 day Space Shuttle flight in June 1998. A proton background suppression on the order of 10^6 is reached by identifying converted bremsstrahlung photons emitted from positrons
Group signatures with verifier-local revocation and backward unlinkability in the standard model
Group signatures allow users to anonymously sign messages in the name of a group. Membership revocation has always been a critical issue in such systems. In 2004, Boneh and Shacham formalized the concept of group signatures with verifier-local revocation where revocation messages are only sent to signature verifiers (as opposed to both signers and verifiers). This paper presents an efficient verifier-local revocation group signature (VLR-GS) providing backward unlinkability (i.e. previously issued signatures remain anonymous even after the signer's revocation) with a security proof in the standard model (i.e. without resorting to the random oracle heuristic).Anglai