Dark matter annihilation at the galactic center

If cold dark matter is present at the galactic center, as in current models of the dark halo, it is accreted by the central black hole into a dense spike. Particle dark matter then annihilates strongly inside the spike, making it a compact source of photons, electrons, positrons, protons, antiprotons, and neutrinos. The spike luminosity depends on the density profile of the inner halo: halos with finite cores have unnoticeable spikes, while halos with inner cusps may have spikes so bright that the absence of a detected neutrino signal from the galactic center already places interesting upper limits on the density slope of the inner halo. Future neutrino telescopes observing the galactic center could probe the inner structure of the dark halo, or indirectly find the nature of dark matter.Comment: 4 pages, 5 figure

Search for point sources of neutrinos with KGF underground muon detectors

The proton decay detectors operated underground in the Kolar Gold Fields in India during 1980-1993 have recorded a large number of muon events. Out of these, 243 large zenith angle events were selected as being due to muons arising from neutrino interactions in the surrounding rock. This selection was based on the different zenith angular distributions of the atmospheric and neutrino-induced muons. These selected events are analysed here to look for powerful point sources of neutrinos

On inconsistency of experimental data on primary nuclei spectra with sea level muon intensity measurements

For the first time a complete set of the most recent direct data on primary cosmic ray spectra is used as input into calculations of muon flux at sea level in wide energy range $E_\mu=1-3\cdot10^5$ GeV. Computations have been performed with the CORSIKA/QGSJET and CORSIKA/VENUS codes. The comparison of the obtained muon intensity with the data of muon experiments shows, that measurements of primary nuclei spectra conform to sea level muon data only up to several tens of GeV and result in essential deficit of muons at higher energies. As it follows from our examination, uncertainties in muon flux measurements and in the description of nuclear cascades development are not suitable to explain this contradiction, and the only remaining factor, leading to this situation, is underestimation of primary light nuclei fluxes. We have considered systematic effects, that may distort the results of the primary cosmic ray measurements with the application of the emulsion chambers. We suggest, that re-examination of these measurements is required with the employment of different hadronic interaction models. Also, in our point of view, it is necessary to perform estimates of possible influence of the fact, that sizable fraction of events, identified as protons, actually are antiprotons. Study of these cosmic ray component begins to attract much attention, but today nothing definite is known for the energies $>40$ GeV. In any case, to realize whether the mentioned, or some other reasons are the sources of disagreement of the data on primaries with the data on muons, the indicated effects should be thoroughly analyzed

Neutrino astronomy with the MACRO detector

High energy gamma ray astronomy is now a well established field and several sources have been discovered in the region from a few GeV up to several TeV. If sources involving hadronic processes exist, the production of photons would be accompanied by neutrinos too. Other possible neutrino sources could be related to the annihilation of WIMPs at the center of galaxies with black holes. We present the results of a search for point-like sources using 1100 upward-going muons produced by neutrino interactions in the rock below and inside the MACRO detector in the underground Gran Sasso Laboratory. These data show no evidence for a possible neutrino point-like source or for possible correlations between gamma ray bursts and neutrinos. They have been used to set flux upper limits for candidate point-like sources which are in the range 10^-14-10^-15 cm-2 s-1.Comment: 37 pages, 15 figures, replacement due to a typo in tab. 6, AASLaTex, submitted to Ap

Deindustrialization in cities of the global south

Recent research by economists has shown that deindustrialization is more severe in Sub-Saharan Africa and Latin America than it ever was in the Organisation for Economic Co-operation and Development (OECD). Nevertheless, most research on deindustrialization is focused on the former centres of Fordist manufacturing in the industrial heartlands of the North Atlantic. In short, there is a mismatch between where deindustrialization is researched and where it is occurring, and the objective of this paper is to shift the geographical focus of research on deindustrialization to the Global South. Case studies from Argentina, India, Tanzania and Turkey demonstrate the variegated nature of deindustrialization beyond the North Atlantic. In the process, it is demonstrated that cities in the Global South can inform wider theoretical discussions on the impacts of deindustrialization at the urban scale

New balloon-borne telescope system tical - Mark II for hard X-ray astronomy

For the study of hard X-rays (18-150 KeV) from the celestial X-ray sources, NaI/CsI phoswich scintillator telescopes have been flown from Hyderabad during the last decade. The NaI(Tl)/CsI(Na) scintillator phoswich with Pulse Shape Discrimination technique reduces the non X-ray background by a factor 10 at balloon altitudes. The new telescope TICAL Mark-II with 1000sq.cm area [5 mm thick NaI(Tl) and 50 mm thick CsI(Na) phoswich] had a sensitivity to detect a minimum flux of 2.2 × 10-6 photons/sq.cm sec KeV in the energy range 18-150 KeV for 104 s exposure; this allows study of several bright active galactic nuclei. The telescope had a microprocessor-based tracking system to automatically follow celestial sources in elevation and azimuth according to a predetermined schedule. Several galactic X-ray sources, mostly binary pulsars, and the quasar 3C273 have been studied. The scintillator phoswich X-ray detector, the X-ray telescope and the electronic systems of the TICAL Mark II will be described

Search for high-energy neutrinos from celestial sources in the Kolar gold fields experiments

Neutrino-induced muons from celestial sources are searched for using KGF nucleon decay detectors. The large-angle penetrating muons produced by muon-neutrinos in the rock surrounding the detector are used. The overall rate of such muons is found to be consistent with that expected from atmospheric neutrinos; no significant excess is seen from any of the sources under consideration

Search for point sources of neutrinos with KGF underground muon Detectors

The proton decay detectors operated underground in the Kolar Gold Fields in India during 1980 - 1993 have recorded a large number of muon events. Out of these, 243 large zenith angle events were selected as being due to muons arising from neutrino interactions in the surrounding rock. This selection was based on the different zenith angular distributions of the atmospheric and neutrino-induced muons. These selected events are analysed to look for powerful point sources of neutrinos