We present the case for a dark matter detector with directional sensitivity. This document was developed at the 2009 CYGNUS workshop on directional dark matter detection, and contains contributions from theorists and experimental groups in the field. We describe the need for a dark matter detector with directional sensitivity; each directional dark matter experiment presents their project's status; and we close with a feasibility study for scaling up to a one ton directional detector, which would cost around $150M.

A direction-sensitive dark matter search experiment at Kamioka underground laboratory with the NEWAGE-0.3a detector was performed. The NEWAGE-0.3a detector is a gaseous micro-time-projection chamber filled with CF 4 gas at 152 Torr. The fiducial volume and target mass are 20 × 25 × 31 cm 3 and 0.0115 kg, respectively. With an exposure of 0.524 kg·days, improved spin-dependent weakly interacting massive particle (WIMP)-proton cross section limits by a direction-sensitive method were achieved including a new record of 5400 pb for 150 GeV/c 2 WIMPs. We studied the remaining background and found that ambient γ-rays contributed about one-fifth of the remaining background and radioactive contaminants inside the gas chamber contributed the rest.

Observations of the PSR B1259À63/SS 2883 binary system using the CANGAROO-II Cerenkov telescope are reported. This nearby binary consists of a 48 ms radio pulsar in a highly eccentric orbit around a Be star and offers a unique laboratory to investigate the interactions between the outflows of the pulsar and Be star at various distances. It has been pointed out that the relativistic pulsar wind and the dense mass outflow of the Be star may result in the emission of gamma rays up to TeV energies. We have observed the binary in 2000 and 2001, $47 and $157 days after the 2000 October periastron. Upper limits at the 0.13-0.54 crab level are obtained. A new model calculation for high-energy gamma-ray emission from the Be star outflow is introduced, and the estimated gammaray flux, considering bremsstrahlung, inverse Compton scattering, and the decay of neutral pions produced in proton-proton interactions, is found to be comparable to the upper limits of these observations. Comparing our results with these model calculations, we constrain the mass-outflow parameters of the Be star.

The Galactic Center has been observed with the CANGAROO-II imaging atmospheric Cherenkov telescope in 2001 and 2002. We detected a statistically significant excess at energies greater than 250GeV. This is the first detection of sub-TeV gamma rays from the Galactic Center region. The signal direction is consistent with the Galactic Center, which includes the massive black hole Sgr A* and supernova remnant Sgr A East. The resultant flux is 1 order of magnitude lower than that of the Crab Nebula at 1 TeV. The differential flux has a steep spectrum and the power law index is observed to be ¢ 4 £ 6 ¤ 0£ 5, although it could flatten to ¢ 3 .4 if the uncertainty in energy determination is included. Here, the analysis for reduction of night sky background effects and the radiation mechanism of sub-TeV gamma rays are reported. The most probable radiation mechanism is π 0 decays. The maximum energy of the inferred cosmic rays is 1-3 TeV and the total cosmic-ray luminosity corresponds to 1 ¥ 10 supernova remnants. We also obtain an upper limit on the cold dark matter density in the galactic halo.

We have detected gamma-ray emission at the 6 σ level at energies greater than 500 GeV from the supernova remnant RX J0852.0−4622 (G266.2−1.2) using the