The nearby active galaxy NGC 1275, has widely been detected from radio to gamma rays. Its spectral energy distribution (SED) shows a double-peak feature, which is well explained by synchrotron self-Compton (SSC) model. However, recent TeV detections
might suggest that very-high-energy $gamma$-rays (E$geq$100 GeV) may not have a leptonic origin. We test a lepto-hadronic model to describe the whole SED through SSC emission and neutral pion decay resulting from p$gamma$ interactions. Also, we estimate the neutrino events expected in a Km$^3$ Cherenkov telescope.
Markarian 421 (Mrk 421) is one of the brightest, fastest and closest BL Lac object known. Its very high energy (VHE) spectrum has been successfully modeled with both leptonic and hadronic models and not conclusive results have been achieved yet about
the origin of its VHE emission. Here we investigate the possibility that a fraction of the VHE flares of Mrk 421 are due to hadronic processes and calculate the expected neutrino flux associated. We introduce the obtained neutrino flux in a Monte Carlo simulation to see the expectation for a Km$^{3}$ Cherenkov neutrino telescope.
Fanaroff-Riley I radiogalaxies have been observed in TeV gamma-rays during the last decades. The origin of the emission processes related with this energy band is still under debate. Here we consider the case of the two closest Fanaroff-Riley I objec
ts: Centaurus A and M87. Their entire broadband spectral energy distributions and variability fluxes show evidences that leptonic models are not sufficient to explain their fluxes above 100 GeV. Indeed, both objects have been imaged by LAT instrument aboard of Fermi telescope with measured spectra well connected with one-zone leptonic models. However, to explain the TeV spectra obtained with campaigns by H.E.S.S., for Centaurus A, and by VERITAS, MAGIC and H.E.S.S. for M87, different emission processes must be introduced. In this work we evoke hadronic scenarios to describe the TeV gamma-ray fluxes observed and to obtain the expected neutrino counterparts for each considered TeV campaign. With the obtained neutrino spectra we calculate, through Monte Carlo simulations, the expected neutrino event rate in a hypothetical Km$^{3}$ neutrino telescope and we compare the results with what has been observed by IceCube experiment up to now.
Very high energy gamma-ray emission of Fanaroff-Riley I objects is not univocally explained by a single emission model. Leptonic models with one and multi-zone emission regions, occurring in the jet of these objects, are usually used to describe the
broadband spectral energy distribution. A correlation between the X-ray and TeV emission is naturally expected within leptonic models whereas a lack of correlation between these two observables represents a challenge and favors the hadronic scenarios. This is the case of M87 as we show here by analyzing its TeV and X-ray emission recorded in the last decade. Furthermore, we point out that the spectra obtained by MAGIC, H.E.S.S. and VERITAS telescopes cannot be described with the same leptonic model introduced by the Fermi-LAT collaboration. We introduce hadronic scenarios to explain the TeV gamma-ray fluxes of this radiogalaxy as products of Fermi-accelarated protons interacting with seed photons in the jet or thermal particles in the giant lobes. By fitting this part of spectral energy distribution as pion decay products, we obtain the expected neutrino counterpart and the luminosity of accelerating protons in the jet and/or lobes. With the expected neutrino fluxes we investigate, through Monte Carlo simulations, the possibility to see the signal from M87 with a Km$^{3}$ neutrino telescope, and compare the results with what has been seen by IceCube experiment up to now. Finally we constrain the features of giant lobes through the observations performed at ultra high energies by TA experiment.
VAMOS was a prototype detector built in 2011 at an altitude of 4100m a.s.l. in the state of Puebla, Mexico. The aim of VAMOS was to finalize the design, construction techniques and data acquisition system of the HAWC observatory. HAWC is an air-showe
r array currently under construction at the same site of VAMOS with the purpose to study the TeV sky. The VAMOS setup included six water Cherenkov detectors and two different data acquisition systems. It was in operation between October 2011 and May 2012 with an average live time of 30%. Besides the scientific verification purposes, the eight months of data were used to obtain the results presented in this paper: the detector response to the Forbush decrease of March 2012, and the analysis of possible emission, at energies above 30 GeV, for long gamma-ray bursts GRB111016B and GRB120328B.
The High Altitude Water Cherenkov (HAWC) observatory is a TeV gamma-ray and cosmic-ray detector currently under construction at an altitude of 4100 m close to volcano Sierra Negra in the state of Puebla, Mexico. The HAWC observatory is an extensive a
ir-shower array comprised of 300 optically-isolated water Cherenkov detectors (WCDs). Each WCD contains $sim$200,000 liters of filtered water and four upward-facing photomultiplier tubes. In Fall 2014, when the HAWC observatory will reach an area of 22,000 m$^{2}$, the sensitivity will be 15 times higher than its predecessor Milagro. Since September 2012, more than 30 WCDs have been instrumented and taking data. This first commissioning phase has been crucial for the verification of the data acquisition and event reconstruction algorithms. Moreover, with the increasing number of instrumented WCDs, it is important to verify the data taken with different configuration geometries. In this work we present a comparison between Monte Carlo simulation and data recorded by the experiment during 24 hours of live time between 14 and 15 April of 2013 when 29 WCDs were active.
