Cosmic Ray Positron and Electron Excess from Hidden-Fermion Dark Matter Decays

The anomalies observed in recent cosmic ray experiments seem to strongly constrain the nature of the dark matter. In this letter, we investigate a possibility of the fermionic dark matter with a minimal extension of the standard model. We found that the dark matter decays caused by the dimension six operators can naturally explain the anomalies.Comment: 10 pages, 8 figures, accepted by PL

Gamma rays and positrons from a decaying hidden gauge boson

We study a scenario that a hidden gauge boson constitutes the dominant component of dark matter and decays into the standard model particles through a gauge kinetic mixing. Interestingly, gamma rays and positrons produced from the decay of hidden gauge boson can explain both the EGRET excess of diffuse gamma rays and the HEAT anomaly in the positron fraction. The spectra of the gamma rays and the positrons have distinctive features; the absence of line emission of the gamma ray and a sharp peak in the positron fraction. Such features may be observed by the GLAST and PAMELA satellites.Comment: 16 pages, 4 figures, adding PAMELA data, the version accepted by PL

R-violating Decay of Wino Dark Matter and electron/positron Excesses in the PAMELA/Fermi Experiments

We show that R-parity violating decay of Wino dark matter of mass \sim 3 TeV can naturally account for the flux and spectral shape of the cosmic-ray electrons and positrons observed by the PAMELA and Fermi satellites. To provide a theoretical basis for the scenario, we also present a model that trilinear R-parity breaking appears with a coefficient suppressed by powers of the gravitino mass, which naturally leads to the Wino lifetime of O(10^26) sec.Comment: 11 pages, 4 figure

High-energy Cosmic-Ray Positrons from Hidden-Gauge-Boson Dark Matter

We provide a scenario in which a hidden U(1) gauge boson constitutes dark matter of the Universe and decays into the standard-model particles through a kinetic mixing with an $U(1)_{B-L}$ gauge boson. Interestingly, our model can naturally account for the steep rise in the positron fraction recently reported by PAMELA. Moreover, we find that due to the charge assignment of $U(1)_{B-L}$, only a small amount of antiprotons are produced in the decay, which is also consistent with the PAMELA and other observational data.Comment: the version appeared in PL

Decaying Hidden Gaugino as a Source of PAMELA/ATIC Anomalies

We study a scenario that a U(1) hidden gaugino constitutes the dark matter in the Universe and decays into a lepton and slepton pair through a mixing with a U(1)B-L gaugino. We find that the dark-matter decay can account for the recent PAMELA and ATIC anomalies in the cosmic-ray positrons and electrons without an overproduction of antiprotons.Comment: 12 pages, 1 figure.v2:a reference adde

Mobile phones and the cultural ecology of fishing in Kerala, India

10.1080/01972243.2011.566756Information Society273172-18

Decrypting E-Governance: Narratives, Power play and Participation in the Gyandoot Intranet

The mapping of the social and political constraints that marginalized communities and individuals encounter in their interface with e-governance projects, perhaps, has implications for the optimistic political vision of new media technologies as a decolonizing force facilitating development of “cyborg skills” required for their survival under techno-human conditions theorized in the cyber-feminist approaches to new technologies. Identifying the structural factors that envelop human technology interaction in the rural setting in South Asia is thus an inevitable step in understanding social innovations and its impacts either initiated by the State or by civil society or by State-civil society partnerships. This paper is an attempt in that direction. The central themes addressed in this paper relate to the critique of the notion of egovernance as an essentially administrative innovation facilitated by ICTs and recognition of e-governance as social process which involves not only attitudinal change and transformation of traditional forms of governmentality but also as a contested arena of social forces shaping the trajectory of the evolution of this technocratic innovation.e-governance, ICT,information technology, South Asia, state-civil society partnership, innovation, technocratic innovation,

Industrial development and the dynamics of innovation in Hong Kong

10.1504/IJTM.2004.004276International Journal of Technology Management274369-392IJTM

ICTs and development: Revisiting the asian experience

10.1177/097172180801300201Science, Technology and Society132159-17