Daniele Fargion
Università degli Studi "La Sapienza" di Roma, Physics and Astronomy, Department Member
Ultra High Energy, UHE, upward Tau neutrinos nutau , ¯nutau , above hundred TeVs and up to tens PeV energies, of relevant astrophysical nature, may lead to UHE Taus and consequent Up-ward Tau air-Showers (UPTAUS) after interaction on... more
Ultra High Energy, UHE, upward Tau neutrinos nutau , ¯nutau , above hundred TeVs and up to tens PeV energies, of relevant astrophysical nature, may lead to UHE Taus and consequent Up-ward Tau air-Showers (UPTAUS) after interaction on Earth crust surface. The UPTAUS discover may open a new UHE Tau Neutrino Astrophysics. A new generation of Gamma, X, optical and Radio Arrays in Space may discover, in the same Auger spirit, such up-coming Airshowers as well as an additional Tau signal: the nearly Horizontal Tau AIR-Shower (HORTAUS) originated by UHE neutrinos tau at 1019 eV energies arising from a thin Earth crust corona at few tens of degree below the horizons; a degree above the horizons, there should be over common diffused cosmic ray albedo, an additional High Altitudes (nearly Horizontal) Showers (HIAS), by more common Cosmic Rays primaries at PeVs up to EeV and ZeV energies, both of hadronic or of electro-magnetic gamma nature. Mini-arrays detectors in high Altitude Balloons tail...
Research Interests:
High Energy Neutrino Astronomy has been revealed by a sudden change in the flavor composition around maximal energies since three years of recording in ice km detector. However these discover didn' t led to any clear promised Neutrino... more
High Energy Neutrino Astronomy has been revealed by a sudden change in the flavor composition around maximal energies since three years of recording in ice km detector. However these discover didn' t led to any clear promised Neutrino Astronomy land yet. No correlation with hard gamma sources was found. Moreover the astrophysical spectra expected at Fermi value, seem to converge to a softer value, also required to avoid any Glashow resonant neutrino signal. We suggest a main solution within a composite flux ruled by prompt atmospheric neutrinos. Nevertheless the recent discover of twentyone crossing muons at hundreds TeVs had shown a first narrow overlapped doublet and a correlated track with a peculiar hard UHECR event clustering pointing to a well known microjet in bynary precession; these first connections hint for a non negligible astrophysical component making neutrino astronomy anyway already more than a hope.
Research Interests:
Research Interests:
Gamma Ray Burst has been widely believed in last decade to be super-explosions: the Fireball. We are argue on the contrary that GRBs (as well as Soft Gamma Repeaters SGR) are precessing Gamma Jets. We remind the list of contradiction that... more
Gamma Ray Burst has been widely believed in last decade to be super-explosions: the Fireball. We are argue on the contrary that GRBs (as well as Soft Gamma Repeaters SGR) are precessing Gamma Jets. We remind the list of contradiction that Fireball and its smaller galactic version, the Magnetar, have to face. In particular the existence of weak isolated X-ray precursor signal before the main Gamma Ray Burst and (rare SGR) events disagree with any explosive, one shoot, scenarios either isotropic or wide-beamed. We interpret them as earlier marginal blazing of outlying X conical Jet tails of precessing, spinning gamma Jet.
Research Interests:
Research Interests:
ABSTRACT
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
ABSTRACT
Research Interests:
Research Interests:
ABSTRACT Primordial heavy neutrinos of 4th generation might explain different astrophysical puzzles: indeed, the simplest 4th neutrino scenario may be still consistent with known 4th neutrino physics, cosmic-ray antimatter and gamma... more
ABSTRACT Primordial heavy neutrinos of 4th generation might explain different astrophysical puzzles: indeed, the simplest 4th neutrino scenario may be still consistent with known 4th neutrino physics, cosmic-ray antimatter and gamma fluxes and signals in underground detectors for very narrow neutrino mass windows (46-47 GeV). We have analyzed extended heavy neutrino models related to the clumpiness of neutrino density, neutrino asymmetry and neutrino decay. We found that in these models the underground signals may be better combined with a cosmic ray im-print leading to wider windows for neutrino mass (46-75 GeV) coinciding with the whole range allowed from the uncertainties of electroweak parameters. pROQWLENIQ TQVELOGO NEJTRINO 4-GO POKOLENIQ W POISKAH SKRYTOJ MASSY k.m. bELOCKIJ, d. fARDVON, m.'. hLOPOW, r.w.kONOPLI k.i. –IBAEW pERWIˆNYE TQVELYE NEJTRINO 4-GO POKOLENIQ MOGUT OB˙QSNQTX RAZLIˆNYE ASTROFIZIˆESKIE ZAGADKI: PROSTEJ-[IJ SCENARIJ S 4-M NEJTRINO WSE E]E SOWMESTIM S FIZIKOJ 4-GO NEJTRINO, DANNYMI PO KOSMIˆESKIM LUˆAM I GAMMA-IZLUˆENI@ I SIGNALAMI W PODZEMNYH DETEKTORAH DLQ OˆENX UZKOGO DIAPAZONA ZNAˆENIJ MASSY NEJTRINO (46-47 g"w). mY PROANALIZIROWALI RAS[IRENNYE MODELI TQVELYH NEJTRINO, SWQZANNYE S MELKOMAS[TABNYMI NEODNORODNOSTQMI (KLAMPAMI) RASPREDELENIQ PLOTNOSTI NEJTRINO, ZARQDOWOJ ASIMMETRIEJ I NESTABILXNOSTX@ NEJTRINO. mY NA[LITO W "TIH MODELQH SIGNALY PODZEMNYH "KSPERIMENTOW MOGUTLUE SOˆETATXSQ S SIG-NALAMI W KOSMIˆESKIH LUˆAH, PRIWODQ K BOLEE [IROKOMU DIAPAZONU ZNAˆENIJ MASSY NEJTRINO (46-75 g"w), SOWPADA@]EMU S TAKOWYM, RAZRE[ENNYM SOWOKUPNOSTX@ DANNYH FIZIKI "LEKTROSLABOGO WZAIMODEJSTWIQ.
Research Interests:
In the Top-down scenarios, the decay of super-heavy particles (m ∼ 10 GeV ), situated in dark-matter halos not very far from our Galaxy, can explain the ultra-high-energy (UHE) cosmic-ray spectrum beyond the Griesen-Zatasepin-Kuzmin (GZK)... more
In the Top-down scenarios, the decay of super-heavy particles (m ∼ 10 GeV ), situated in dark-matter halos not very far from our Galaxy, can explain the ultra-high-energy (UHE) cosmic-ray spectrum beyond the Griesen-Zatasepin-Kuzmin (GZK) cut-off. In case the dynamics of this decay is governed by the minimal supersymmetric standard model, a major component of the UHE cosmic-ray flux at PeV-EeV energies could be given by the lightest neutralino χ01, that is the lightest stable supersymmetric particle. Then, the signal of UHE χ01’s on earth might emerge over the interactions of a comparable neutrino component. We compute the event rates for the resonant production of right selectrons (ẽR) and right squarks (q̃R) in mSUGRA, when UHE neutralinos of energy Eχ ∼ 10 5 GeV scatter off electrons and quarks in an earth-based detector like IceCube. The production rates and decay widths into the same initial particles χ01e, χ 0 1q turn out to be nearly model independent (the resonance and neutralino physical masses being the only relevant parameters) for the neutralino-electron scattering, and also for the neutralino-nucleon scattering, whenever gluinos are heavier than squarks. We compare the expected number of supersymmetric events with the rates corresponding to the Glashow W resonance and the continuum UHE νN scattering for realistic powerlaw spectra. We find that the supersymmetric event rate can reach a few tens for a one-year exposure in IceCube. Finally, we note that UHE neutralinos at much higher energies (up to hundreds ZeV) may produce sneutrino (ν̃) resonances by scattering off relic neutrinos in the Local Group hot dark halo. The consequent ν̃ burst into hadronic final states could mimic a Z-burst event, but with a quite smaller conversion efficiency.
Research Interests:
Research Interests:
Research Interests:
Upward and horizontal τ Air-showers emerging from the Earth crust or mountain chains offer the best and most powerful signal of Ultra High Energy UHE neutrinos ντ, Math and Math at PeV and higher energy. The multiplicity in τ Air-showers... more
Upward and horizontal τ Air-showers emerging from the Earth crust or mountain chains offer the best and most powerful signal of Ultra High Energy UHE neutrinos ντ, Math and Math at PeV and higher energy. The multiplicity in τ Air-showers secondary particles, \({N_{opt}} \simeq {10^{12}}({E_\tau }/PeV),{N_\gamma }( \sim 10MeV) \simeq {10^8}({E_\tau }/PeV),{N_{{e^ - }{e^ + }}} \simeq 2\cdot{10^7}({E_\tau }/PeV),{N_\mu } \simeq 3\cdot{10^5}{({E_\tau }/PeV)^{0.85}}\) make easy its discover. UHE ν τ , ν τ following Super Kamiokande evidence of neutrino flavour mixing, (ν µ ↔ ν τ ), should be as abundant as ν µ, Math. Also anti-neutrino electrons, Math, near the Glashow W resonance peak, \( {E_{{{\bar v}_e}}} = M_W^2/2{m_e} \simeq {6.310^{15}}eV \), may generate τ Air-showers. Such horizontal τ air-showers by ν τ N and UHE Math at PeV emerging from mountain high chain might be the most power-full UHE neutrino imprint. Upward UHE v τ - N interaction on Earth crust at horizontal edge and from below, their consequent UHE τ air-showers beaming toward high mountains should flash γ,µ,X and Cherenkov lights toward detectors located on the top of the mountain or balloons. Such upward τ air-shower may hit also nearby satellite flashing them by short, hard, diluted γ-burst at the edge of Gamma Ray Observatory BATSE threshold. We identify already these rarest gamma events with recent (1994) discovered upward Terrestrial Gamma Flashes (TGF); we show their very probable UHE τ -UHE ντ origin. Partial TGF Galactic signature and known galactic and extra-galactic source location are discovered within known 47 TGF events at low, ≃ 2 · 10-3 probability threshold.
Research Interests:
The differential gravitational synchrotron radiation power emitted by a bunch of rotating charges is derived. The 'local' and 'resonant' emissions are evaluated. Nonrelativistic and ultrarelativistic limits are... more
The differential gravitational synchrotron radiation power emitted by a bunch of rotating charges is derived. The 'local' and 'resonant' emissions are evaluated. Nonrelativistic and ultrarelativistic limits are discussed. Bunches of photons in dissipationless toroidal fiber optics are found as the best sources of gravitational waves. A holographic array, the holograver, made up of small coherent fiber optic rings, allows focalizing in a wavelength radius of almost all the gravitational waves power reaching the largest available artificial gravitational waves flux and metric deviations. For a storaged energy E in all the holograver, the flux and metric deviation are obtained.
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests: Physics, Spectroscopy, Cosmic Rays, Astrophysics, Neutrino, and 4 moreKey words, Tau, UHECR, and Zenith
Research Interests:
The Sun albedo of Cosmic Rays (CRs) at GeVs energy has been discovered recently by the FERMI satellite. They are traces of atmospheric CRs hitting solar atmosphere and reflecting skimming gamma photons. Even if relevant for astrophysics,... more
The Sun albedo of Cosmic Rays (CRs) at GeVs energy has been discovered recently by the FERMI satellite. They are traces of atmospheric CRs hitting solar atmosphere and reflecting skimming gamma photons. Even if relevant for astrophysics, as being a trace of atmospheric solar CR noises they cannot offer any signal of neutrino astronomy. On the contrary, the Moon with no atmosphere, may become soon a novel filtering calorimeter and an amplifier of energetic muon astronomical neutrinos (at TeV up to hundred TeVs energy); these lepton tracks leave an imprint in their beta decay while in flight to Earth. Their TeV electron air-shower are among the main signals. Also, a more energetic, but more rare, PeV up to EeV tau lunar neutrino events may be escaping as a tau lepton from the Moon: [Formula: see text] PeV secondaries, then, may be shining on Earth’s atmosphere in lunar shadows in a surprising way. One or a few gamma air-shower events inside the Moon shadows may occur each year in near...
Research Interests:
Ultra High Cosmic Rays) made by He-like lightest nuclei might fit clustering along Cen A. Moreover He like UHECR nuclei explain Virgo absence because the light nuclei fragility and opacity above a few Mpc. We foresaw (2009) that UHECR He... more
Ultra High Cosmic Rays) made by He-like lightest nuclei might fit clustering along Cen A. Moreover He like UHECR nuclei explain Virgo absence because the light nuclei fragility and opacity above a few Mpc. We foresaw (2009) that UHECR He from Cen-A AGN being fragile should partially fragment into secondaries at tens EeV multiplet (D,He^{3},p) as the recent twin multiplet discovered ones (AUGER-ICRC-2011), at 20 EeV along Cen A UHECR clustering. We suggest that UHECR are also heavy radioactive galactic nuclei as Ni^{56}, Ni^{57} and Co^{57} widely bent (tens degree up to 100 degrees) by galactic fields. UHECR radioactivity and decay in flight at hundreds keV is boosted (by huge Lorentz factor (billion) leading to PeVs electrons and consequent synchrotron TeVs gamma offering UHECR-TeV correlated sky anisotropy. Electron and tau neutrinos secondaries at PeVs maybe the first signature of such expected radioactive secondary tail.
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Soft Gamma Repeaters are widely believed to occur as isotropic Magnetar explosion. We suggest on the contrary that they may be described by thin collimated spinning and precessing gamma jets, flashing and blazing along the line of sight.... more
Soft Gamma Repeaters are widely believed to occur as isotropic Magnetar explosion. We suggest on the contrary that they may be described by thin collimated spinning and precessing gamma jets, flashing and blazing along the line of sight. The jet (for SGRs) may be powered by an accretion disk in binary system and it produces huge outflows and blazing features
Research Interests:
Research Interests:
Electron neutrino has been the first neutral lepton to be foreseen and discovered last century. The un-ordered muon and its neutrino arose later by cosmic rays. The tau discover, the heaviest, the most unstable charged lepton, was found... more
Electron neutrino has been the first neutral lepton to be foreseen and discovered last century. The un-ordered muon and its neutrino arose later by cosmic rays. The tau discover, the heaviest, the most unstable charged lepton, was found surprisingly on 1975. Its neutrino was hardly revealed just on 2000. So why High Energy Neutrino Astronomy should rise first via tau neutrino, the last, the most rare one? The reasons are based on a chain of three favorable coincidences found last decade: the neutrino masses and their flavor mixing, the UHECR opacity on Cosmic Black Body (GZK cut off on BBR), the amplified tau air-shower decaying in flight. Indeed guaranteed UHE GZK tau neutrinos, feed by muon mixing, while skimming the Earth might lead to boosted UHE tau, mostly horizontal ones. These UHE lepton decay in flight are spread, amplified, noise free Air-Shower: a huge event for an unique particle. To be observed soon: within Auger sky, in present decade. Its discover may sign of the firs...
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Upward and horizontal tau Air-showers emerging from the Earth crust or mountain chains are the most powerful signals of Ultra High Energy UHE neutrinos nu_{tau}, bar\nu_{tau} and bar{nu}_e at PeVs and higher energy. The multiplicity in... more
Upward and horizontal tau Air-showers emerging from the Earth crust or mountain chains are the most powerful signals of Ultra High Energy UHE neutrinos nu_{tau}, bar\nu_{tau} and bar{nu}_e at PeVs and higher energy. The multiplicity in tau Air-showers secondary particles, N_{opt}=10^{12}(E_{tau}/PeV), N_{gamma}= 10^8*E_{tau}/PeV, N_{e^- e^+}= 2*10^7 E_{tau}/PeV, N_{mu}= 3 *10^5 (E_{tau}/PeV)^{0.85} make easy their discover. UHE nu_tau,bar\nu_tau, following Super Kamiokande evidence of neutrino flavor mixing, nu_munu_tau, should be as abundant as nu_mu, bar\nu_mu. Also anti-neutrino electrons, bar\nu_e, near the Glashow W resonance energy peak, E_{bar\nu_e} = M^2_W / 2m_e = 6.3*10^{15} eV may generate tau Air-showers. Upward UHE nu_tau- N interaction on Earth crust at horizontal edge and from below, their consequent upward UHE tau air-showers beaming toward high mountains, air-planes, ballons and satellites should flash gamma, mu, X and Cherenkov lights toward detectors. Such upward ...
Research Interests:
Weak isolated X-ray precursor events before the main Gamma Ray Burst, GRB, and also rare Soft Gamma Repeaters, SGR, events are in disagreement with any Fireball, or Magnetar, scenarios. These models are originated by an unique explosive... more
Weak isolated X-ray precursor events before the main Gamma Ray Burst, GRB, and also rare Soft Gamma Repeaters, SGR, events are in disagreement with any Fireball, or Magnetar, scenarios. These models are originated by an unique explosive event leading, by internal-external shock waves, to softer secondary trains following a main gamma signals. Indeed the earliest GRB980519,GRB981226 events as well as the latest and most distant identified one as GRB000131 are showing rare but well identified and distinct X Ray precursor, occurring tens of seconds or even a minute before the main GRB eruption. These weak X precursors bursts correspond to non-negligible energy powers, up to million Supernova ones. They are rare, about (3-6)% of all GRBs, but not unique. Similar huge explosive precursor are in total disagreement with a successive main Fireball GRB outburst. Comparable brief X-ray precursor flashes are found also in rarest and most detailed SGRs events as those observed on 27 and 29 Augu...
Research Interests:
ABSTRACT
Research Interests:
Research Interests:
High Energy Neutrino Astronomy has been revealed by a sudden change in the flavor composition above 30 TeV since 2013 by IceCube detector: the fast growth of spherical showers over atmospheric muon track signal in IceCube marked the... more
High Energy Neutrino Astronomy has been revealed by a sudden change in the flavor composition above 30 TeV since 2013 by IceCube detector: the fast growth of spherical showers over atmospheric muon track signal in IceCube marked the revolution. However these discover didn't led to the promised Neutrino-Astronomy-Land yet. AGN flaring are not correlated with these high energy tens TeV-PeV events. Brightest persistent or pulsed galactic sources are missing while no point source arise in the lower energy sky. GRB events do not correlate within any minute-hour lapse time windows along any neutrino event. Moreover the astrophysical hard spectra whose exponent was expected at Fermi value of −2, seem to converge from −2.2 to a softer −2.7 or −3.0 value, also needed to avoid unobserved Glashow resonant neutrino at 6.3 PeV energy. Finally a key question arises: why within the ten UHE neutrino, those harder than 200 TeV events (whose timing structure would allow IceCube to disentangle any double tau neutrino imprint) don't double bang anyway? We suggest a main solution within a composite flux mostly ruled by prompt atmospheric neutrinos. Nevertheless in the very recent discover of 21 through-going (crossing) muons at hundreds TeVs, whose tracks are more aligned and telling, is shown a first narrow doublet (and some of correlated UHECR clustered source); this points – or give hints – for a non-negligible 10 − 20% astrophysical component, making neutrino astronomy already alive anyway.