With the increase in center-of-mass energy, a new energy frontier has been opened by the Large Hadron Collider. More than 25 fb^-1 of proton-proton collisions at sqrt(s)=13 TeV have been delivered to both ATLAS and CMS experiments during 2016. This enormous dataset can be used to test the Standard Model in a complete new regime with tremendous precision and it has the potential to unveil new...
There is overwhelming indirect evidence that dark matter exists, however, the dark matter particle has not yet been directly detected in laboratory experiments. In order to be able to identify the rare dark matter interactions with the target nuclei, such instruments have to feature a very low threshold and an extremely low radioactive background. They are therefore installed in underground...
Axions are a natural consequence of the Peccei-Quinn mechanism, the most compelling solution to the strong-CP problem. Similar axion-like particles (ALPs) also appear in a number of possible extensions of the Standard Model, notably in string theories. Both axions and ALPs are very well motivated candidates for the Dark Matter, and in addition would be copiously produced at the stellar cores....
DM searches using missing ET at LHC (CMS)
We present a precision measurement of the cosmic-ray proton flux at rigidity from 1 GV to 1.8 TV and the helium flux at rigidity from 2 GV to 3 TV. The measurement is based on the data collected by the Alpha Magnetic Spectrometer experiment on the International Space Station. The two fluxes are found to progressively harden at rigidities larger than 100 GV, while the proton-to-helium ratio is...
Varying Yukawas open new possibilities for electroweak baryogenesis. In this talk I will focus on the CP-violation and the baryon-asymmetry (for details on the strength of the phase transition, see abstract by Iason Baldes). Starting from first principles, I will derive the general form of the CP-violating semiclassical force and the diffusion equations for models with varying Yukawa...
Precision measurements by the Alpha Magnetic Spectrometer on the International Space Station of the primary cosmic-ray electron flux in the range 0.5 to 700 GeV and the positron flux in the range 0.5 to 500 GeV are presented. The electron flux and the positron flux each require a description beyond a single power-law spectrum. Both the electron flux and the positron flux change their behavior...
Searches for light dark matter through dijets and long-lived particles at the LHC
The Compton Spectrometer and Imager (COSI) is a balloon-borne, gamma ray imager, spectrometer, and polarimeter with sensitivity from 0.2 to 5 MeV. Utilizing a compact Compton telescope design with twelve cross-strip, high-purity germanium detectors, COSI has three main science goals: study the 511 keV positron annihilation line from the galactic plane, image diffuse emission from stellar...
A precision measurement by AMS of the antiproton flux and
the antiproton-to-proton flux ratio in primary cosmic rays in the
absolute rigidity range from 1 to 450 GV is presented based on $3.49
\times 10^5$ antiproton events and $2.42 \times 10^9$ proton events. The
antiproton-to-proton flux ratio reaches a maximum at ∼20 GV and is
rigidity independent above 60.3 GV.
It has been recently shown that if dark matter is produced at the LHC via spin-0 mediators, multijet+MET searches are more sensitive than the standard monojet ones. We have recast the latest multijet+MET analysis using 13 TeV data, to show the present and future prospects of exclusion power of this signal. We apply these constraints to several DM well motivated models, including the...
Interactions that manifest themselves as lepton number violating processes at low energies in combination with sphaleron transitions typically erase any pre-existing baryon asymmetry of the Universe. We demonstrate in a model independent approach that the observation of lepton number violation, namely in neutrinoless double beta decay and at the LHC, would impose a stringent constraint on...
Expensive detector simulations are in general required to assess the implications of LHC data on extensions of the Standard Model of particle physics, as they allow to directly compare the predicted phenomenology for a given point in (an often high-dimensional) theory parameter space, with actual data. We show here that a suitable application of advanced machine learning methods that can...
I will first describe the experimental setup with which we took data at different photon energies from 1.7MeV to 74MeV, and with different polarisation configurations.
I will present the software I developed to reconstruct the photon conversion events, especially for low energies.
I will also introduce the complete detailed simulation I made of the detector.
Finally I will present the...
Astroparticle physics of Galactic cosmic rays (CR) has entered a new level of precision with the measurements of AMS-02. On the other hand, uncertainties in CR production in the sources and in their propagation are still large. We thus perform a global analysis of injection and propagation parameters testing how the current diffusion models perform in the light of the new precise data. Using...
In this talk I will start by considering a question which curiously had not been properly considered so far: in the standard seesaw model what is the minimum value the mass of a right-handed (RH) neutrino must have for allowing successful leptogenesis via CP-violating decays? I show that, for low RH neutrino masses and thanks to thermal effects, leptogenesis turns out to proceed efficiently...
The CALET Gamma-ray Burst Monitor (CGBM) is the secondary scientific instrument of the CALET mission on the International Space Station (ISS), which was successfully launched and attached to the International Space Station (ISS) at the end of August 2015 and began scientific operations in October 2015.
The CGBM consists of two LaBr3(Ce) and one BGO scintillators, each read by a single...
One of the possible sources of hadronic cosmic rays (CRs) are newborn pulsars. If it is indeed the case, they should feature diffusive gamma-ray halos produced by interactions of CRs with interstellar gas. In my talk I will report on the attempts to identify extended gamma-ray emission around young pulsars making use of the 7-year Fermi-LAT data.
I will describe the method and the selected...
The extension of the Standard Model by heavy right-handed neutrinos can simultaneously explain the observed neutrino masses via the seesaw mechanism and the baryon asymmetry of the Universe via leptogenesis. If the mass of the heavy neutrinos is below the electroweak scale, they may be found at LHCb, BELLE II, the proposed SHiP experiment or a future high-energy collider. In this mass range,...
After the monumental discovery of the Higgs boson, the LHC presently confronts the major challenge in searching for new physics. Any such observation necessitates the determination of mass and other quantum numbers like spin, polarization etc for the new resonance. Most of the BSM theories motivated from profound experimental indication of dark matter (DM), trying to accommodate them as some...
The High Altitude Water Cherenkov (HAWC) Observatory has been fully operational since its inauguration on 20 March 2015. HAWC opens a new window for survey observations of gamma rays and cosmic rays in the very high energy (VHE) range from 100 GeV to 100 TeV, facilitating studies of Galactic and extragalactic particle accelerators, indirect dark matter searches, gamma-ray bursts, and many...
We present a combined analysis of the recent AMS-02 data on electrons, positrons, electrons plus positrons and positron fraction. We consider a self-consistent framework where we realize a theoretical modeling of all the astrophysical components that can contribute to the observed fluxes. The primary electron contribution is modeled through a smooth spatial distribution of distant supernova...
One of the most promising way to detect dark matter is to look for its annihilation or decay products among cosmic-rays. Especially, it is found that quite strong constraints can be imposed by the gamma-ray measurements of dwarf spheroidal galaxies. However, recent studies reveal that these constraints are largely affected by the uncertainty of the dark matter halo density. In this talk, we...
The Precision IceCube Next Generation Upgrade (PINGU) is a proposed low-energy in-fill extension to the IceCube Neutrino Observatory that will feature the world's largest effective mass of a few MTon for neutrinos at an energy threshold of a few GeV. The unprecedented statistical sample of GeV-scale atmospheric neutrinos will enable PINGU to quickly and at a modest cost investigate the...
The particle physics nature of the dark matter is one the top unknowns in physics. The Particle and Astrophysical Xenon (PandaX) project is a series of xenon-based experiments in the China Jin-Ping Underground Laboratory (CJPL). The first and second stage experiments (PandaX-I and II) both utilize dual-phase xenon time-projection chamber to carry out direct search for the dark matter...
We present the new Third Catalog of Hard Fermi-LAT Sources, dubbed 3FHL, which describes the sky at energies above 10 GeV. Relying on 7 years of data and the Pass 8 event level analysis, this catalog reports the detection of more than 1700 sources, representing a huge step forward relative to the 1FHL, which characterizes the sky at the same energies. The improved flux sensitivity (factor of...
We use the Maximum Likelihood technique to derive the density profile parameters of the the dark matter halos containing the Dwarf Spheroidal Galaxies of the Milky Way. This is done using the Jeans equation formalism on the the stellar kinematic data available for such systems. The method is validated on simulated data generated by the Gaia Challenge team.
The XENON program aims at direct detection of Weakly Interacting Massive Particles (WIMPs) detection with dual phase xenon time projection chambers (TPCs), located at the Laboratori Nazionale de Gran Sasso. This contribution is going to review recent results of the still operational XENON-100 detector, as well as discuss the status and prospects for the presently commissioned XENON-1T...
The observation of EeV astrophysical neutrinos will be a significant scientific achievement, and the radio-frequency Antarctic neutrino observatories represent the cutting edge in the field of high-energy neutrino science. Being electrically neutral, astrophysical neutrinos propagate directly from the highest-energy objects in the cosmos, and could reveal the source of the highest energy...
A broadband study of high-z (z>3) blazars enables us to understand the evolution of the properties of relativistic jets over cosmic time. Moreover, it has been found in many studies that such high-z blazars host extremely massive black holes (M$_{BH}$> 1e9 M$_{\odot}$) and thus shed a new light on the formation of supermassive black holes in the early Universe. Here we report the first...
The Diffuse Gamma-Ray Background (DGRB) collects the radiation produced by all those sources that are not bright enough to be resolved individually. Therefore, it represents an essential tool to study faint gamma-ray emitters, like star-forming or radio galaxies and the exotic Dark Matter. The anisotropy pattern of the DGRB is extremely informative: I will review the recent measurement of the...
A brief introduction to two-phase xenon TPCs, the details of the LUX project, illustration of how signals are reconstructed, details of calibrations, analysis and background estimates, and presentation of the most recent results
The KM3NeT Collaboration aims at the discovery and subsequent observation of high neutrino sources in the Universe (ARCA) and at the determination of the neutrino mass hierarchy (ORCA). The KM3NeT technologies, current status and expected performances are reported. In particular the ARCA detector is described and its perspectives for detection of high energy neutrinos signals from different...
The blazars Mrk421 and Mrk501 are among the brightest keV and TeV sources in the sky, and among the few sources whose (radio to VHE gamma-rays) Spectral Energy Distributions (SEDs) can be characterized by current instruments by means of relatively short observations (minutes to hours). Consequently, Mrk421 and Mrk501 can be studied with a larger degree of accuracy than most of the other...
Anisotropies in the electromagnetic emission produced by dark matter (DM) annihilation
or decay in the extragalactic sky are a recent tool in the quest for a particle DM evidence.
In particular, the angular two-point cross-correlation signal between non-gravitational DM emissions and the gravitational manifestation of DM has been shown to be a promising novel technique to disentangle a WIMP...
The ANTARES high energy neutrino telescope, the largest in the Northern Hemisphere and the first one ever built under the sea, has been running in its final configuration since 2008. It is located in the Mediterranean Sea 40 km off the Southern coast of France, at a depth of 2.5 km.
After the discovery of a cosmic neutrino diffuse flux by the IceCube detector, the search for its origin has...
PKS1510-089 is a flat spectrum radio quasar with a redshift of 0.36 and is one of the few such sources detected in very-high-energy (VHE, >100 GeV) gamma rays. PKS1510-089 is highly variable at GeV energies, but until recently no variability in the VHE range has been observed.
In 2015 May PKS1510-089 showed a high state in optical and in the GeV range. MAGIC observations performed at that...
I will discuss a model-independent approach to calculate the spectra arising from dark matter annihilations or decays into intermediary particles with arbitrary spin, which subsequently produce neutrinos or photons via two-body decays. I illustrate this with two examples. First, with the neutrino spectra arising from dark matter annihilations into the massive Standard Model gauge bosons....
The DarkSide-50 experiment employs a dual-phase liquid argon time projection chamber inside a system of two active veto detectors to directly search for WIMP dark matter. DarkSide-50 has recently performed a background-free search using 70 live days of data with low radioactivity argon extracted from underground, setting the strongest limit to date on the WIMP-nucleon elastic cross section...
We performed a set of time dependent and multi-messenger searches for neutrino flaring emissions from astrophysical sources. We present the results of three searches applied to IceCube data measured between April 2008 and April 2015. The most generic search is an un-triggered scan for clustering of track like IceCube events simultaneously in both, time and direction. The second one is a...
Massive black holes in active galaxies are surrounded by bulges of both evolved late type and also young luminous stars in nuclear stellar clusters. The luminous stars can enter a jet region which contain fast moving blobs filled with relativistic electrons. We calculate
the gamma-ray spectra and light curves produced by these electrons in the Inverse Compton electron-positron pair cascade...
We evaluate the prompt atmospheric neutrino flux at high energies using different QCD frameworks for calculating the heavy quark production cross section in collisions of cosmic ray protons and atmospheric nuclei. We use QCD parameters consistent with heavy quark production cross sections measured at fixed target experiments, such as RHIC and LHC, to deduce a band of uncertainty for charm and...
Angular power spectrum is getting more and more important in recent years to study components of the diffuse gamma-ray background. Understanding constituents through this and other measurements is extremely important for our generic knowledge on high-energy sky. If we are interested in searching for new physics such as dark matter annihilation, it is essential to address all possible...
will be based on
A.~Cuoco, J.~Q.~Xia, M.~Regis, E.~Branchini, N.~Fornengo and M.~Viel,
%``Dark Matter Searches in the Gamma-ray Extragalactic Background via Cross-correlations With Galaxy Catalogs,''
Astrophys.\ J.\ Suppl.\ {\bf 221} (2015) no.2, 29
doi:10.1088/0067-0049/221/2/29
[arXiv:1506.01030 [astro-ph.HE]]
M.~Regis, J.~Q.~Xia, A.~Cuoco, E.~Branchini, N.~Fornengo...
Dwarf spheroidal galaxies are among the most important targets in the search for gamma rays from dark matter annihilation in the cosmos. In fact, joint likelihood analyses using dozens of dwarfs have recently reached the sensitivity necessary to test the putative dark matter signal detected from the Galactic center. While the gamma-ray flux from conventional astrophysical emission processes...
Towards CP violation: from T2K to HyperK.
This talk follows announcements earlier this year by the LIGO and Virgo Scientific Collaborations, based on data from the first
four-month observing run the advanced LIGO gravitational wave
detectors (aLIGO). In two instances, on 14.9.2015 and on 26.12.2015, we have directly detected the gravitational waves emitted by the final orbits and merger of massive black hole binary systems. I...
In the past year, the LIGO-Virgo Collaboration announced the first secure detection of gravitational waves. This discovery heralds the beginning of gravitational wave astronomy: the use of gravitational waves as a tool for studying the dense and dynamical universe. In this talk, I will describe the full spectrum of gravitational waves, from Hubble-scale modes, through waves with periods of...
Abstract: IceCube's discovery of a diffuse flux of astrophysical neutrinos started a new era of neutrino astronomy.I will review the multiple diffuse analyses in IceCube that observe the astrophysical flux, and what each can tell us. Then I will focus on spatial analyses that aim to identify the sources of such astrophysical neutrinos. This will be followed by an attempt to reconcile all...
A core-collapse supernova is a nearly perfect neutrino bomb. While capable of outshining its entire host galaxy, this stunning light show represents just a small portion of the explosion. Indeed, each such cataclysmic event typically radiates two orders of magnitude more energy as low-energy neutrinos than it does as electromagnetic radiation or as kinetic shockwaves. Consequently, MeV-scale...
The discovery of astrophysical neutrinos at high energy by IceCube raises a host of questions: What are the sources? Is there a Galactic as well as an extragalactic component? How does the astrophysical spectrum continue to lower energy where the dominant signal is from atmospheric neutrinos? Is there a measureable flux of cosmogenic neutrinos at higher energy? What is the connection to cosmic...
Since June 2006 the PAMELA satellite-borne experiment has presented fundamental results on various aspects of cosmic-ray physics. Above all, PAMELA investigated the features present in the antiparticle component of galactic cosmic rays, which have been interpreted in terms of DM annihilation or pulsar contribution. The combination of a permanent magnet with a silicon-strip spectrometer and a...
Under general circumstances, the Standard Model Higgs is excited in the form of a condensate during or towards the end of inflation. The Higgs condensate is then forced to decay afterwards — due to non-perturbative effects — into the rest of the SM species. I will present the cosmological implications of this primordial decay, quantifying the necessary conditions to achieve a successful...
We investigate the production of gravitational waves during the preheating process after inflation in the common case of field potentials that are asymmetric around the minimum where the universe reheats. In particular, we study the impact of oscillons, comparatively long lived and spatially localized regions where a scalar field (e.g. the inflaton) oscillates with large amplitude. Contrary to...
The nuclei fluxes with rigidity and their ratios are important for understanding the production, acceleration and propagation mechanisms of cosmic rays. Latest result from the Alpha Magnetic Spectrometer on the International Space Station of the light nuclei measurement will be presented.
In view of the latest publications of the primary CR fluxes, namely proton and helium flux from AMS-02 and CREAM, we aim at re-evaluating the positron flux coming from conventional astrophysical processes, i. e. secondary positrons. Moreover, we plan to estimate how the experimental uncertainties on the primary CR fluxes affect the secondary positron flux, computed by means of a new...
The search for neutrinoless double beta decay (0$\nu\beta\beta$) might be the only window to observe lepton number violation. Its observation would have many implications in neutrino physics (Majorana nature, mass scale and ordering, etc) and beyond.
The GERmanium Detector Array (GERDA) experiment, located at the Laboratori Nazionali del Gran Sasso, has been constructed to search for this...
Status of eLISA; Gravitational waves from first-order phase transitions; BSM physics with first-order phase transitions.
I will present the results of the scan of the parameter space for cosmic ray (CR) injection and propagation of Two-Halo-Model (THM). A Bayesian analysis is performed with Markov Chain Monte Carlo algorithm (MCMC). In THM, the propagation halo is divided into two different regions along the z-axis: inner and outer, where CRs will suffer from different propagation effects. We use proton and...
The search for WIMP dark matter by direct detection faces an encroaching background due to coherent neutrino nucleus scattering. In this talk I will review the various types of neutrino that are backgrounds to direct detection - Solar, supernovae and atmospheric neutrinos - and explain how their presence results in the theoretical limit known as the neutrino floor. The proximity of the...
Gravitational waves are a promising new observational tool, not only for astrophysics but also for cosmology. In various extensions of the Standard Model the phase transition can be first order, and could produce copious gravitational waves from bubble collisions. Other possibilities, such as a tachyonic transition at the electroweak scale, produce a more subdued signature at higher...
I will talk about ongoing research into aspects of the fact that the next generation of dark matter detectors will detect neutrinos. I will describe some of the physics which will be constrained using such detections and also new methods to both eliminate and study the neutrino background.
We revisit the production of baryon asymmetries in the minimal type I seesaw model with heavy Majorana singlets in the GeV range. In particular we include for the first time "washout" effects from scattering processes with gauge bosons and higgs decays and inverse decays, besides the dominant top scatterings. We show that in the minimal model with two singlets, and for an inverted light...
The direct detection experiments are reaching new limits in the upcoming searches. Among other things, they will be sensitive to the coherent neutrino scattering background. I will demonstrate the effect of new physics scenarios on the neutrino background at the direct detection experiments. I will further describe the impact on the dark matter constraints due to such a change in the neutrino...
We investigate the capability of various configurations of the space interferometer eLISA to probe the late-time background expansion of the universe using gravitational wave standard sirens. We simulate catalogues of standard sirens composed by massive black hole binaries whose gravitational radiation is detectable by eLISA, and which are likely to produce an electromagnetic counterpart...
Abstract
The Jiangmen Underground Neutrino Observatory (JUNO) is a neu- trino reactor experiment at kt scale which will address the mass hierar- chy problem. The detector consists of a 20 kt Liquid Scintillator target and will be based in an deep underground laboratory (700 m) located at 53 km distance from the Yangjiang and Taishan nuclear power plant site in China. This specific location...
Review talk on the high-energy interstellar gamma-ray emission from the Milky Way
Newborn pulsars and magnetars turn out to be very promising sources to accelerate cosmic rays up to high and ultrahigh energies, thanks to their rotational and magnetic energy reservoirs. Interestingly, most scenarios that involve hadronic acceleration in these objects should lead to copious amount of neutrino production. Indeed, pulsars and magnetars are not born naked, but surrounded by a...
The ISS-based CALET (Calorimetric Electron Telescope) detector is directly measuring the energy spectrum of electron+positron cosmic rays up to 20 TeV with an expected energy resolution of 2%. With an estimated proton rejection capability of 1 : 10$^5$ and an aperture of approximately 1200 cm$^2$ sr, it will provide good statistics even well above one TeV. This precise spectrum is going to be...
SHIP is a new general purpose fixed target facility, whose Technical Proposal has been recently reviewed by the CERN SPS Committee and by the CERN Research Board. The two boards recommended that the experiment proceeds further to a Comprehensive Design phase in the context of the new CERN Working group "Physics Beyond Colliders", aiming at presenting a CERN strategy for the European Strategy...
The cumulative emission resulting from hadronic cosmic-ray interactions in star-forming galaxies (SFGs) has been proposed as the dominant contribution to the astrophysical neutrino flux at TeV to PeV energies reported by IceCube.
The same particle interactions also inevitably create gamma-ray emission that could be detectable as a component of the extragalactic gamma-ray background (EGB),...
We developed a new semi-analytical method to better estimate the propagated cosmic-ray positron flux from a few hundreds MeV to 1 TeV.
It allows us to take into account Galactic convection, energy losses inside the disc and diffusive reacceleration, that are often neglected or badly considered
as most of the analyses concentrate on energies above 10 GeV.
Therefore, we are now able to...
Despite several gamma-ray observational campaigns of clusters of galaxies in the last years, both by Fermi-LAT and Cherenkov telescopes, the diffuse high-energy emission that is expected to come from cosmic-ray hadronic interactions with the abundant ambient gas remains elusive. Nevertheless, we significantly improved our understanding of non-thermal phenomena in clusters. I will summarize the...
The antiproton-to-proton ratio is about to be published by the AMS collaboration. Any excess with respect to the astrophysical background could potentially be the eagerly awaited signal for the presence of WIMPs inside the Milky Way. These massive and weakly interacting species are natural candidates for the astronomical dark matter. Pervading the Galaxy, they are expected to pair-annihilate...
The Antarctic neutrino observatory IceCube (IC) has detected a robust diffuse flux signal consistent with neutrinos of extragalactic origin. To date, none of the observed neutrinos have been associated with point sources or transient events. New analyses by the IC and Fermi collaborations have introduced tension between electromagnetic measurements and the gamma-ray signal theorized to...
We analyze the present bounds of a scotogenic model, the Radiative Type III Seesaw (RSIII), in which an additional scalar doublet and at least two fermion triplets of $SU(2)_L$ are added to the Standard Model (SM). In the RSIII the new physics (NP) sector is odd under an exact global $Z_2$ symmetry. This symmetry guaranties that the lightest NP neutral particle is stable, providing a natural...
The GAPS experiment is foreseen to carry out a dark matter search by hunting for low-energy cosmic-ray antideuterons with a novel detection approach. The theoretically predicted antideuteron flux resulting from secondary interactions of primary cosmic rays, e.g. protons, with the interstellar medium is very low. So far not a single cosmic antideuteron has been detected by any experiment, but...
Gamma-ray bursts (GRBs) are potential sources of high-energy (> 100 TeV) neutrinos and ultra-high-energy (> 10^9 GeV) cosmic rays (UHECRs). Recent neutrino searches have constrained the connection between them in the one-zone version of the internal shock model. It calculates the prompt particle emission from a single representative collision of plasma shells in the GRB jet, assuming that the...
Statistical properties of photon count maps have recently been proven to provide a sensitive observable for characterizing gamma-ray source populations and for measuring the composition of the gamma-ray sky with high accuracy. In this contribution, we generalize the use of the standard 1-point probability distribution function (1pPDF) to decompose the high-latitude gamma-ray emission observed...
We present a classification of simplified models of coannihilating dark matter. Assuming tree-level and renormalizable interactions we construct all possible simplified models (containing dark matter, its coannihilation partner and a mediator) which respect gauge and Lorentz invariance. We go on to identify the possible LHC signatures associated with these models and identify new search...
In this talk, I will present an analysis of the extragalactic gamma-ray background (EGB) using data from the Fermi Large Area Telescope. The method takes advantage of photon-count statistics to determine the properties of resolved and unresolved gamma-ray sources that contribute to the EGB. I will present the source-count functions, as a function of energy, from 1.89 GeV to 2 TeV, as well as...
I analyze the constraints on Dark Matter from direct and indirect detection and from the LHC in the case in which the interaction between the DM particle and the SM ones is spin-dependent. This can happen for example if the DM is a Majorana fermion and the interaction is mediated by a heavy Z’, or in the case in which the mediator is a pseudo-scalar (having in mind the possible 750 GeV...
Antideuterons are a potential messenger for dark matter annihilation or decay in our own galaxy, with very low backgrounds expected from astrophysical processes. The standard coalescence model of antideuteron formation, while simple to implement, has potentially large uncertainties from Monte Carlo modelling, and is under considerable strain by recent data from the LHC. We suggest two new...
Blazars are prime candidate sources for the high energy neutrinos recently detected by IceCube. Being intrinsically variable sources at almost all wavelengths, an accurate modeling of their neutrino emission in both quiescent and flaring states is vital for the interpretation of observations by neutrino telescopes. I will summarize our results on the neutrino emission obtained by the...
Difficulties in explaining the origin of the high energy neutrinos observed by Icecube using traditional astroparticle physics have motivated ideas this flux could in part be due to the decay of PeV scale dark matter. In such scenarios, the decay is necessarily associated with the production of gamma rays at much lower energies that can be observed by Fermi-LAT. This is true even for decays...
We consider particle acceleration in the vacuum gaps in split-monopole magnetospheres of slow and maximally rotating black holes, embedded in the radiatively-inefficient accretion flow (RIAF) environment. The gap height is limited by the onset of gamma-gamma pair production on the infrared photons originating in the RIAF.
We numerically calculate the acceleration and propagation of charged ...
During the last decades, various classes of radio-loud active galactic nuclei have been established as sources of high-energy radiation extending over a very broad range from soft gamma-rays (photon energies E~MeV) up to very-high-energy gamma-rays (E>100 GeV). These include blazars of different types, as well as young and evolved radio galaxies. The observed gamma-ray emission from such...
Many theoretical ideas for the particle nature of dark matter exist. The most popular models often predict that dark matter particles self-annihilate or decay, giving rise to potentially detectable signatures in astronomical observations. I will summarize the current status of searches for such signatures and critically reassess recent claims for dark matter signals. I will further provide...
It is well known that CMB is a very powerful tool to constraints Dark Matter decays, even if this decay happens in some invisible -so called "dark"- radiation.
I would like to show that, in multi-component models, or more generally for non-trivial dark sector decoupled from standard model, CMB can constraints both lifetime and abundance of decaying dark matter into dark radiation (that could...
The firm establishment of gamma-ray sources of dark matter is often impeded by source confusion. Conventional astrophysical sources can mimic hypothetical dark matter sources, manifested in unidentified sources in the Fermi-LAT catalogues or in the GC excess. In statistical terms, the question of whether a sources is dark matter or conventional astrophsyics is an example of a non-standard ...
The new generation of powerful instruments are reaching sensitivities and temporal resolutions that will allow a multi-messengers detection of transient phenomena. In this study, we explore the parameter-space of flaring sources (in particular in terms of luminosity, time-variability or emission energy band) that would enable the detection of transient neutrino signatures. We consider...
One of a promising asymmetric dark matter model is the mirror model, where the gauge group is doubled the standard model (SM) gauge group, i.e. SU(3)$_1$$\otimes$SU(3)$_2$ $\otimes$SU(2)$_L$$\otimes$SU(2)$_R$ $\otimes$U(1)$_{Y1}$$\otimes$U(1)$_{Y2}$, and the particles content consist of the ordinary (o) SM particles (plus the right handed neutrinos) and their parity mirror (m) partners. To...
Cygnus X-1 is the prototype black hole high-mass microquasar.
As a persistent and bright X-ray source is considered an optimal candidate
to study the disk-jet coupling. It displays the typical soft and hard X-ray
spectral states of black hole binaries where the emission is dominated by
the thermal black body radiation and by non-thermal emission from the inner
part of the disk and the...
In this talk we introduce DRAGON2, the new version of the public
software package designed to study Cosmic Ray (CR) propagation in the Galaxy. Our
aim is to illustrate the approach followed in the writing of the code and to
present its most important features. We describe the properties of the numerical
scheme that has been adopted to implement all the processes related to CR
transport...
We consider a natural extension of the Minimal Dark Matter scenario where Dirac and Majorana SU(2)_L multiplets couple together via the Higss. We classify and study in a systematic way all the few possible models consistent with the absence of Landau poles up to very high scale, including the results for Direct Detection, and the Sommerfeld-enhanced annihilation. We demonstrate that, at...
Extensive air shower (EAS) arrays with muon identification capability are ideal
to investigate diffuse $\gamma$-rays at multi-TeV energies. The GRAPES-3
experiment at Ooty in India is equipped with a dense array of 400 scintillator
detectors and a large area (560 m$^2$) tracking compact muon detector. It is
designed to investigate $\gamma$-rays and cosmic ray nuclear composition in...
In this talk I will describe the main effects due to Einstein's general relativity on the stability of the electroweak vacuum. A perturbative (weak gravity) expansion will be discussed.
Local measurements of Galactic cosmic-ray antiprotons are known to provide constraints on the properties of annihilating cold dark matter (CDM). It is also known that CDM candidates generically lead to the structuring of matter on scales much smaller than typical galaxies. This clustering translates into a very large population of subhalos in galaxies, which induces an enhancement of the...
We estimate the annihilation (J) factors of non-spherical dark halos in the Galactic dwarf spheroidal (dSph) galaxies.
This is motivated by the fact that most of such estimations have so far treated the dSphs and their dark halos as spherical systems for simplicity, even though the luminous parts of dSphs as well as the shapes of dark halos predicted by cold dark matter simulations are not...
Weakly Interactive Massive Particles (WIMPs) are among the most favored Dark Matter candidates.
As the Solar System moves through Dark Matter halo, the WIMPs may scatter on the nuclei in the
Sun/Earth, lose energy, and get trapped by their gravitational potentials. Their capture and subsequent
annihilations in the core of Sun/ Earth may subsequently give rise to neutrinos, through various...
The MAGIC telescopes can potentially detect very-high-energy gamma-rays emitted by multi-messenger sources.
One such interesting target that has been found recently, is astrophysical neutrino events.
Gamma-ray observations of neutrino directions have a potential to find hadronic gamma-ray emissions from the neutrino directions and to identify neutrino sources.
The IceCube Collaboration has...
Our galactic plane is a diffuse heterogeneous emitter at high and very high energies. Several gamma-ray campaigns, like that of Fermi-LAT in the GeV range and H.E.S.S. and Milagro in the TeV range, reported an enhanced diffuse emission from different regions of the plane. With a comprensive cosmic-ray transport model, able to reproduce the observed gamma-ray spectra from the galactic plane, we...
We perform a spectral and anisotropic one-point-fluctuation analysis of high-energy Icecube data, based on data-driven modelling of both galactic and extragalactic contributions to the flux.
In baseline scenarios, energetic astrophysical neutrinos are produced in decays of charged pions, which in turn originate from proton-proton or proton-gamma collisions. Neutral-pion decays produce an accompanying gamma-ray flux, and observational data on gamma rays and cosmic rays impose serious constraints on scenarios explaining the origin of IceCube high-energy events. I review these...
New observational tests of anomalies in absorption of gamma rays from distant sources, which may point to existence of light axion-like particles, are discussed. Constraints on parameters of the would-be axion-like particle are presented and various scenarios are tested.
Detection of ~ 0.1-70 GeV prompt gamma-ray emission from the exceptionally bright gamma-ray burst (GRB) 130427A by the Fermi-Large Area Telescope provides an opportunity to explore the physical processes of GeV gamma-ray emission from the GRB jets. In this work we discuss interactions of Iron and Oxygen nuclei with observed keV-MeV photons in the jet of GRB 130427A in order to explain an...
The current large area cosmic ray detector surface arrays typically measure only the net flux and arrival-time of the charged particles produced in an extensive air shower (EAS). Measurement of the individual charged particles at a surface array will provide additional distinguishing parameters to identify the primary and to map the very high energy interactions in the upper layers of the...
The main aim of the ANTARES neutrino telescope is to detect neutrinos from astrophysical sources. Due to its location, ANTARES has a privileged visibility of the Galactic Centre, which provides the most stringent sensitivities for this region for neutrino energies below 100 TeV. The latest results of the all-flavour neutrino analysis for point and extended sources using data from 2007 to 2015...
High-energy astrophysical neutrinos are a novel arena to test for the presence of new neutrino physics. With them, we can look for new physics at scales of tens of TeV to a few PeV, far beyond the reach of laboratory experiments. Even tiny modifications from new physics might accumulate over the presumed cosmological-scale baselines and become detectable. New physics models include, for...
We use a two point correlation analysis to look for inhomogeneities in the arrival directions of the high energy muon neutrino candidates detected by the ANTARES neutrino telescope. This
approach is complementary to a point source likelihood-based search, which is mainly sensitive
to single point like sources and not to collective effects. We present the results of a search
based on this...
Abstract : Axion-like particles (ALPs) as an extension of the standard model define a generic class of light pseudo-sclars with a rich phenomenology because of their coupling to photons. Here we explore a so-far neglected opportunity to search for ALPs-photon coupling in the disappearance channel, i.e. a characteristic energy dependent suppression of gamma-rays. To verify this phenomenon...
We present the software StellarICs in development since 2013, year of the first release.
Dwarf spheroidals (dSphs) are low-luminosity satellite galaxies of the Milky Way highly dominated by dark matter. Therefore, they are prime targets to search for signals from dark matter annihilation using gamma-ray observations. Recent stellar kinematical data show that the dark matter density profiles are better described by axisymmetric profiles than by the traditionally used spherically...
One of the key predictions of the “WIMP” paradigm for Dark Matter (DM) is that DM particles can annihilate into charged particles. These annihilations will proceed in e.g. Galactic subhalos such as dwarf Galaxies or, as recently pointed out, high velocity clouds such as the “Smith” cloud. In this talk I will argue that among the several messengers of the DM annihilations occurring in the Smith...
Cen A is the nearest radio-galaxy detected as a VHE gamma-ray source. Discovered by the H.E.S.S. telescopes in Namibia, Cen A is a faint VHE gamma-ray emitter, and the flux derived from the H.E.S.S. data is much higher than that expected from a single zone SSC model which adequately describes the emission from Cen A at lower frequencies. New observations with H.E.S.S. were performed to...
The presence of large scale TeVs anisotropy in Milagro, ARGO, ICECUBE
and today Hawc sky remain a mistery: how may charged cosmic rays at tens
TeV remain correlated while being bent by local solar and galactic
magnetic fields in an expected smeared nearly homogeneous maps? We
considered UHECR as mostly light (or partial heavy) radioactive nuclei
whose decay in flight may feed by alfa and...
S5 0716+714 is a well known BL-Lac object, characterized by an extreme variability across the whole electromagnetic spectrum. The discovery in the Very High Energy band (VHE, E> 100 GeV) by MAGIC happened in 2008, but at that time Fermi-LAT data were not yet available. During January 2015 the source went through the brightest optical state ever observed, triggering MAGIC follow-up...
The blazar S4 0954+65 (at a disputed redshift of z=0.368 or z>=0.45) underwent an exceptionally high state in optical during January and February 2015, as revealed by the Tuorla and St. Petersburg University blazar monitoring programs: a brightening of more than 3 magnitudes in the R-band from the average monitored states. Simultaneous data from the Fermi/LAT satellite at high energy gamma...
On 14 September 2015, the advanced LIGO gravitational wave instruments detected the gravitational wave signal emitted as two black holes, about one billion light years away from Earth, made a final few orbits around each other then merged together. This was big news around the world, because scientists have tried to make such observations for more than half a century. Before they merged, the...
The next generation of cosmological surveys (of large scale structures, CMB polarisation, 21cm line), approved (Euclid, SKA, ...) or submitted (COrE+, LiteBird), have the potential to return a lot of relevant information for particle physics. I will present and comment some of the most recent sensitivity forecasts related to neutrino physics, light relics and Dark Matter properties.
The Alpha Magnetic Spectrometer, AMS, is a general purpose high energy particle phys- ics detector. It was installed on the International Space Station, ISS, on 19 May 2011 to conduct a unique long duration mission of fundamental physics research in space. Knowledge of the precise rigidity dependence of the proton and helium flux is important in understanding the origin, acceleration, and...
Over the past decade, gamma ray astrophysics has entered the astrophysical mainstream. Extremely successful space-borne (GeV) and ground-based (TeV) detectors, combined with a multitude of partner telescopes, have revealed a fascinating “astroscape" of active galactic nuclei, pulsars, gamma ray bursts, supernova remnants, binary stars, star-forming galaxies, novae much more, exhibiting major...
I will present recent results on the Galactic Center from the Fermi-LAT Collaboration using 6.5 years of LAT Pass 8 data, and comparisons with previous works. My talk will focus on our new analysis of the Galactic Center that includes the Fermi Bubbles in some detail; in particular I will show the effect on the previously reported Galactic excess from low-latitude emission from the Fermi...
Calculating the neutralino relic density is a strong possibility to identify favoured and disfavoured regions of the parameter space of a supersymmetric theory such as the MSSM. With the latest results of the Planck mission, the cosmological parameters including the dark matter abundance are determined to an unprecedented precision. In order to reduce the theoretical uncertainty in the...
Fermi-LAT observations have discovered a gamma-ray excess emanating from the Galactic center of the Milky Way. While this excess may be explained by populations of gamma-ray pulsars or by dark matter annihilation, it is worth noting that the intensity of this excess is comparable to the systematic uncertainties in the diffuse astrophysical gamma-ray emission near the Galactic plane. Thus, a...
A trilinear coupling between an inflaton and the Standard Model Higgs boson opens up an exponentially enhanced decay channel. Such a coupling is for instance generically present in a combined Goldstone Inflation and Composite Higgs scenario. Here I will discuss our analysis of such a scenario and its constraints, paying attention to both the feasibility of the production of Standard Model...
We show that simplified models used to describe the interactions of dark matter with Standard Model particles do not in general respect gauge invariance and that perturbative unitarity may be violated in large regions of the parameter space. The modifications necessary to cure these inconsistencies may imply a much richer phenomenology and lead to stringent constraints on the model. We...
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The nature of the Galactic diffuse gamma-ray emission as measured by the Fermi Gamma-ray Space Telescope has remained an active area of research for the last several years. In particular, the discovery of a GeV excess towards the Galactic center has generated enormous interest in trying to understand its origins, whether astrophysical or more exotic. While most analyses of the GeV excess...
A mixed dark matter model consists of a cold dark matter (CDM) fraction and a fraction given by another dark component (non-cold). The free-streaming length increases with the velocity of the dark matter particle, varying from a scale value of Mpc for a warm dark matter component up to the size of Universe for a relativistic species that we label as dark radiation.
We study these models...
Several groups have demonstrated the existence of an excess in the gamma-ray emission around the Galactic Center (GC) with respect to the predictions from a variety of Galactic Interstellar Emission Models (GIEMs) and point source catalogs. The origin of this excess, peaked at a few GeV, is still under debate. A possible interpretation is that it comes from a population of unresolved...
As results from Run II of the LHC continue to be released, it is important to evaluate the ways in which we study DM at colliders. EFTs can be a useful tool to constrain DM in a semi-model-independent way, but it is now clear that this approach has limitations.
EFTs are now supplemented by simplified models of dark matter, and it is important to approach these models in a logical and...
In this talk I will present the most recent generation of standard solar models (SSM) that include the latest developments in the input physics entering its calculations, most notably updated nuclear reaction rates and radiative opacity calculations and experimental results. I will describe the impact on SSM predictions for helioseismic diagnostics and solar neutrino fluxes and, in the light...
The dark matter experiment XENON1T is now operational and sensitive to all flavors of neutrinos emitted from a supernova through coherent elastic neutrino-nucleus scattering. We show that the proportional scintillation signal (S2) allows for a clear observation of the neutrino signal and guarantees a particularly low energy threshold, while the backgrounds are rendered negligible during the SN...
An excess of diffuse gamma-rays towards the Galactic Center (GC) is usually assumed to originate from the GC with the most exciting interpretations being the contributions from dark matter (DM) annihilation and/or unresolved sources, like millisecond pulsars.
Up to now no studies have been undertaken to see if the excess occurs in other regions of the Galactic plane, which is a challenge,...
We present an interpretation of the excess in the gamma-ray emission from the center of our galaxy observed by Fermi-LAT in terms of dark matter annihilation within the scalar singlet Higgs portal model. In particular, we include the astrophysical uncertainties from the dark matter distribution and allow for unspecified additional dark matter components. We demonstrate through a detailed...
Scalar-tensor modifications of gravity have long been considered as an alternative explanation for the late-time accelerated expansion of our Universe. I will first show that a rigorous discrimination between acceleration from modified gravity and from a cosmological constant or dark energy is not possible with observations of the large-scale structure alone. I will then demonstrate how...
We present the physics potential of a future galactic supernova observation in probing neutrino properties. Particular attention will be devoted to neutrino oscillations in supernovae. It will be also discussed the modification of the observable supernova neutrino signal induced by the
Super-Kamiokande (SK), a large water Cherenkov detector located
underground at the Kamioka Observatory in Japan,
can search for weakly interacting massive particles (WIMPs)
by detecting WIMP-induced neutrinos from the Sun and the Milky Way.
An excess of neutrinos from the Sun and Milky Way direction were
searched for compared to the expected atmospheric neutrino background.
For the...
I present the results of large kinetic (particle-in-cells) plasma simulations of particle acceleration at non-relativistic collisionless shocks, which in particular allow a first-principles investigation of diffusive acceleration at the blast waves of supernova remnants, the most prominent sources of Galactic cosmic rays (CRs).
Ion acceleration efficiency and magnetic field amplification are...
Advanced LIGO's first scientific run, between September 2015 and January 2016, will be
historically remembered for the first direct detection of gravitational waves from an
astrophysical source. This run also provided the first direct evidence for the existence
of stellar-mass black hole binaries. In this talk, we will present details of the
detected sources, their astrophysical...
Gravitational-wave astronomy has made a tremendous stride forward with detections during the first observing run of the Advanced Laser Interferometer Gravitational-wave Observatory (LIGO). The signals have been identified as originating from the merger of black holes, whose parameters it was possible to infer.
In this talk I will explain how the parameter inference from gravitational-wave...
Low-latitude Fermi-LAT data, together with the high resolution gas (CO & HI) and the dust opacity maps, has been recently exploited to study the radial emissivity of γ-rays induced by interactions of cosmic rays (CRs) with the interstellar medium along the Galactic Plane.
Both the absolute emissivity and the energy spectra of γ-rays exhibit significant variations along the galactic...
Advanced LIGO's direct observation of gravitational radiation from a binary black hole merger has sent quakes through the physics and astronomy community. In a few short years, the search for gravitational waves will complete its transformation from an experimental effort into a new discipline of observational astronomy as we rapidly build a sample of merging compact binaries. However, the...
IceCube evidence for extraterrestrial neutrinos poses the intriguing puzzle concerning their origin. The 4-years IceCube HESE data show a 2-sigma excess at low energy (60 - 100 TeV) with respect to an astrophysical power-law with spectral index -2, predicted by the standard Fermi mechanism. Moreover, the IceCube MESE data exhibit an excess located in the same energy range in both southern and...
A.Donath on behalf of the H.E.S.S. collaboration.
H.E.S.S. (High Energy Stereoscopic System) is a hybrid array of five imaging
atmospheric Cherenkov telescopes in Namibia, operating in the very-high-energy (VHE) gamma-ray energy range between ~20 GeV and 100 TeV. In the past decade H.E.S.S. has conducted deep observations of Galactic regions of utmost importance for understanding...
The nature and the origin of ultra-high energy cosmic rays (UHECRs), above 10^{17} eV, is still unknown. The Pierre Auger Observatory has been operating for more then 10 years obtaining a number of major breakthroughs. To answer the open questions on UHECRs the Observatory was conceived as an hybrid detector consisting of fluorescence telescopes overlooking an array of water Cherenkov stations...
This talk is based on the recent review 1602.04816, which contains contributions from many different authors. Rather than focusing on any particular aspect, I aim to give a condensed summary of the status of the field.
There are several types of Galactic sources that can potentially accelerate charged particles up to GeV and TeV energies. These accelerated particles can produce Very High Energy (VHE) gamma-ray emission through different processes like inverse Compton scattering of ambient photon fields by accelerated electrons.
We present here the results of our observations on X-ray and gamma-ray binaries...
Gamma Cygni SNR (G78.2+2.1) is one of the first supernova remnants (SNR) detected in the high-energy gamma-ray band. It is a middle-aged SNR (~7000 years old) situated in the Cygnus region. The high-energy observations by VERITAS and Fermi-LAT revealed a complex, energy-dependent morphology of the SNR in the GeV-TeV band, different from that observed in X-rays. G78.2+2.1 also hosts the pulsar...
The Telescope Array (TA) is an observatory for the study of the highest energy cosmic rays (HECR). Located in Utah, U.S.A., TA consists of a surface scintillator array and a set of nitrogen fluorescence detectors which jointly allow hybrid reconstruction of cosmic ray induced extensive air showers. In this talk we will describe the cosmic ray energy spectrum as measured by TA over five orders...
In this talk, I would like to review how the combination of CMB power spectra, spectral distortions and BBN can be used to put stringeant constraints on the lifetime and abundance of exotic particles (such as dark matter but not only) with electromagnetic decay products. I will emphasize that this has the major advantages over cosmic rays of beeing (almost) free of theoritical uncertainties...
The direct detection of gravitational waves with Advanced LIGO has opened up the possibility of probing the genuinely strong-field dynamics of pure spacetime for the first time. Several tests of general relativity (GR) were carried out with the gravitational wave events GW150914 and GW151226. In the case of GW150914, the merger itself was in the most sensitive part of the detectors' frequency...
Axionlike particles (ALPs) are dark-matter candidates that occur in a variety of extensions of the Standard Model. Signatures of these particles could be detected at gamma-ray energies with the Fermi Large Area Telescope (LAT) due to the coupling of ALPs to photons in external electromagnetic fields. To date, Fermi-LAT observations provide the strongest constraints on the photon-ALP coupling...
A stochastic background of gravitational waves can be described as a superposition of several uncorrelated contributions. It can be of both cosmological and astrophysical origin. In the first case, it can constitute potentially a unique probe of the primordial universe. In the second, it can give precious information on stellar populations.
After discussing how this kind of signal can be...
Many LHC measurements are already used to improve hadronic interaction models used in cosmic ray analyses. This already had a positive effect on the model dependence of crucial data analyses. Some of the data and the model tuning is reviewed. However, the LHC still has a lot more potential to provide crucial information. Since the start of Run2 the highest accelerator beam energies are reached...
The data we are receiving from galactic cosmic rays are reaching an unprecedented precision, over very wide energy ranges. Nevertheless, many problems are still open, while new ones seem to appear when data happen to be redundant. We will discuss some paths to possible progress in the theoretical modelling and experimental exploration of the galactic cosmic
radiation.
I outline the goals of the future LHC programme, and the current understanding of the physics potential of the possible next generation of lepton and hadron colliders.
An accurate determination of the local dark matter (DM) density is crucial to interpreting data from direct detection and certain indirect detection experiments, as it is degenerate with the DM-nucleon interaction strength. Here I give an update to our ongoing project to make a determination of the local DM density. Our method uses the positions and velocities of a set of tracer stars...
The HAWC Observatory in Sierra Negra, Mexico has recently recorded its trillionth cosmic-ray air shower in just over 1 year of operation. Using this high statistics data set, we have studied the arrival direction distribution of ~1-100 TeV cosmic rays. The sub-degree angular resolution of the air shower reconstruction allows us to examine the known features of the Northern TeV cosmic-ray sky...
VERITAS is an array of imaging atmospheric Cherenkov telescopes devoted to the study of the gamma-ray sky in the energy range between 85 GeV and > 30 TeV. VERITAS observations enable a broad program of scientific inquiry, including the study of extreme astrophysical sources both within and beyond our galaxy, the search for dark matter, and a number of topics in astroparticle physics. We...
The IceCube Neutrino Observatory has accumulated a total of 318 billion cosmic-ray induced muon events between May 2009 and May 2015. This data set was used for a detailed analysis of the cosmic-ray arrival direction anisotropy in the TeV to PeV energy range. The observed global anisotropy features large regions of relative excess and deficit, with amplitudes on the order of $10^{-3}$ up to...
The High Altitude Water Cherenkov (HAWC) gamma-ray observatory is a continuously operated, wide field-of-view (FOV) observatory sensitive to 100 GeV - 100 TeV gamma rays. HAWC has been making observations since summer 2012 and officially commenced data-taking operations with the full detector in March 2015. With an instantaneous FOV of 2 steradians, HAWC observes 2/3 of the sky in 24 hours and...
Observations with the Fermi Large Area Telescope indicate an excess in gamma rays originating from the center of our Galaxy. A possible explanation for this excess is the annihilation of Dark Matter (DM) particles. We have investigated the annihilation of neutralinos as DM candidates within the phenomenological Minimal Supersymmetric Standard Model (pMSSM) and found solutions that are not...
NEWS collaboration submitted Letter of Intent to the Gran Sasso Scientific
Committee last year. Since a few years a lot of R&D is undertaken in emulsion and scanning technologies in the collaboration. We would like to report ongoing activities; reporting the update on our sensitivity including the direction information. Please consider abstract below for oral presentation in the TeV particle...
The search for cosmic positron anisotropy has been performed using particles collected by the Alpha Magnetic Spectrometer on the International Space Station. The positron to electron ratio is consistent with isotropy at all energies and angular scales. The analysis of the positron to proton ratio yields consistent results.
Effective theories are a great tool to present constraints on broad BSM assumptions in a rather model-independent fashion. However, effective theories have a limited range of validity which can, especially in collider searches, complicate an analysis. We argue that in order to achieve a consistent analysis more specific hypotheses about BSM physics are needed and can subsequently be tested....
The past two decades have seen a rapid development of $\gamma$-ray astronomy, in particular at energies above a few hundred MeV where Fermi-LAT has revolutionised the field. As a result, extensive studies have been undertaken to characterise gamma-ray annihilation spectra of dark matter with masses above $\sim 1 \mathrm{\,GeV}$. However, due to the lacking sensitivity of current experiments at...
Recent data from CMS and ATLAS experiments at CERN LHC suggest a diphoton excess of invariant mass around 750 GeV. Apparently the width of the resonance is around 45 GeV. To explain this anomaly we introduce a singlet scalar and a dark sector comprising of a vector-like lepton doublet and a singlet which are odd under a Z_2 symmetry. As a result the dark matter emerges as an admixture of the...
Standard Model and Dark sector can be related via a (pseudo)scalar mediator particle, 'messenger'. The scenario belongs to a wider class of 'simplified models' of DM. One can think the models expand the pure effective operator interactions including the degrees of freedom of a mediator particle. We will present some physical scenarios having a TeV scale messenger (for example, 750 GeV). We...
Dark matter decays or annihilations that produce line-like spectra may be smoking-gun signals. However, even such distinctive signatures can be mimicked by astrophysical or instrumental causes. We show that velocity spectroscopy-the measurement of energy shifts induced by relative motion of source and observer-can separate these three causes with minimal theoretical uncertainties. The...
High energy cosmic ray electrons and positrons probe the local properties of
our Galaxy. In fact, regardless of the production mechanism, electromagnetic
energy losses limit the typical propagation scale of GeV-TeV electrons and
positrons to a few kpc.
In the diffusion model, the presence of nearby and dominant sources may produce
an observable dipole anisotropy in the cosmic ray...
In this talk I will present the concept of the DARWIN detector, discuss its physics reach in various channels, the main sources of backgrounds, as well as the ongoing detector design and R&D efforts.
It is well known that a star can capture dark matter (DM) particles, which
condense close to its center and eventually annihilate. In this work, we
trace capture, evaporation and annihilation rates
throughout the life of a massive star and show that it culminates in an
intense annihilation burst coincident with the death of the star in a core
collapse supernova. The reason is...
Momentum-dependent couplings between dark matter and the visible sector can appear in models where dark matter is a pseudo-Nambu-Goldstone boson, a scalar field associated with the spontaneous breaking of a global symmetry at a given energy scale. From a low-energy perspective, these couplings appear as non-renormalizable operators involving derivatives at the effective Lagrangian level. The...
IceTop and IceCube have observed a mysterious cold spot in the angular distribution of high energy ($\ge 100$ TeV) cosmic rays (CR), thereby placing interesting constraints on their transport properties. We examine here these constraints by comparing the observations with the predictions of pitch-angle diffusion in various kinds of turbulence. In the case of Alfvenic turbulence with a...
The Alpha Magnetic Spectrometer (AMS-02) has published the unprecedentedly precise measurement of the cosmic electron and positron spectra， as well as the positron fraction and anti-proton fraction. We have given a quantitative study on the AMS-02 results by a global fitting to the electron and positron spectra, together with the positron fraction data. The primary electron spectrum and the...
The model T12A addresses two major questions of modern particle physics: by adding fermionic and bosonic singlets and doublets to the Standard Model particle content, this model allows to radiatively generate neutrino masses, while at the same time it includes viable candidates for the cold dark matter in our Universe.
We present the first extensive study of the parameter space of this model...
