Air-shower spectroscopy at horizons

Fargion, Daniele

doi:10.1016/j.ppnp.2005.11.015

Cited by 12 publications

(5 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Motivated by recent results in which searches for upward-directed or Earth-skimming CR air showers have been used to constrain the flux of τ lepton decays arising from UHE ν τ [6][7][8], we have performed more detailed evaluation of the properties of these apparently upcoming radio-detected CRs. The three stratospheric events appear consistent with our expectations for ANITA's acceptance to the known CR flux at energies above 10 18 eV.…”

mentioning

confidence: 99%

Characteristics of Four Upward-Pointing Cosmic-Ray-like Events Observed with ANITA

Gorham¹,

Nam²,

Romero-Wolf³

et al. 2016

Phys. Rev. Lett.

135

195

View full text Add to dashboard Cite

We report on four radio-detected cosmic-ray (CR) or CR-like events observed with the Antarctic Impulsive Transient Antenna (ANITA), a NASA-sponsored long-duration balloon payload. Two of the four were previously identified as stratospheric CR air showers during the ANITA-I flight. A third stratospheric CR was detected during the ANITA-II flight. Here, we report on characteristics of these three unusual CR events, which develop nearly horizontally, 20-30 km above the surface of Earth. In addition, we report on a fourth steeply upward-pointing ANITA-I CR-like radio event which has characteristics consistent with a primary that emerged from the surface of the ice. This suggests a possible τ-lepton decay as the origin of this event, but such an interpretation would require significant suppression of the standard model τ-neutrino cross section.

show abstract

mentioning

confidence: 99%

Characteristics of Four Upward-Pointing Cosmic-Ray-like Events Observed with ANITA

Gorham¹,

Nam²,

Romero-Wolf³

et al. 2016

Phys. Rev. Lett.

135

195

View full text Add to dashboard Cite

show abstract

“…a few clusters of triggered pixels, as is shown in [16]. The estimated event rate for such showers in the case of a MAGIC-like detector is at the level of about one event per two minutes for CR showers of energies above E CR > 60 PeV [28].…”

Section: Accepted Manuscriptmentioning

confidence: 78%

Limits on the flux of tau neutrinos from 1 PeV to 3 EeV with the MAGIC telescopes

Ahnen

Ansoldi

Antonelli

et al. 2018

Astroparticle Physics

View full text Add to dashboard Cite

A search for tau neutrino induced showers with the MAGIC telescopes is presented. The MAGIC telescopes located at an altitude of 2200 m a.s.l. in the Canary Island of La Palma, can point towards the horizon or a few degrees below across an azimuthal range of about 80 degrees. This provides a possibility to search for air showers induced by tau leptons arising from interactions of tau neutrinos in the Earth crust or the surrounding ocean. In this paper we show how such air showers can be discriminated from the background of very inclined hadronic showers by using Monte Carlo simulations. Taking into account the orography of the site, the point source acceptance and the event rates expected have been calculated for a sample of generic neutrino fluxes from photo-hadronic interactions in AGNs. The analysis of about 30 hours of data taken towards the sea leads to a 90% C.L. point source limit for tau neutrinos in the energy range from 1.0 × 10 15 eV to 3.0 × 10 18 eV of about E 2 ν τ × φ(E ν τ) < 2.0 × 10 −4 GeV cm −2 s −1 for an assumed power-law neutrino spectrum with spectral index γ=-2. However, with 300 hours and in case of an optimistic neutrino flare model, limits of the level down to E 2 ν τ × φ(E ν τ) < 8.4 × 10 −6 GeV cm −2 s −1 can be expected.

show abstract

“…However, because of the larger area and smaller energy threshold, MAGIC may reveal PeVs neutrino induced signals on nearby clouds. One should note that the twin MAGIC view toward ( [9,7]) and opposite GRBs-SGRs-BL Lac active γ sources direction, while at horizon, can be performed: while one telescope can follow the source beyond the edge, the second telescope could point, in presence of a cloudy sky, the same direction but opposite to the source position. This location is not just a point region but a flat arc, projected by the horizon edges into cloudy sky, where any UHE skimming τ may rise and flash on such a screen.…”

Section: Reflecting On the Sea Ground Or Clouds Around Magicmentioning

confidence: 99%

“…Only rarely Čerenkov jets are observed in axis being split far away into their twin lobes; the higher energy muon bundles survive, being harder than electron ones, reaching the ground almost undeflected along the main shower axis. Such a downward twin spot discover would offer a new UHECR spectroscopy at the horizon (inclined showers) [9]. Čerenkov earliest twin lights define, indeed, the UHECR original direction, its most probable cross-section and its consequent primary composition.…”

mentioning

confidence: 98%

“…Čerenkov light's intensity and color (spectra), zenith angle, traversed column depth, angular separation, time structure and muons component delay and multiplicity, defines primary energy and composition. Moreover, such a pedagogical in-axis event, where the lobes split, even if rare could be enhanced by time correlated muon light rings (by secondary muon Čerenkov imprint [9,11,12,13]). The MAGIC-II telescope array [2], as well as VERITAS and HESS, should discover such inclined events if looking horizontally [15].…”

mentioning

confidence: 99%

See 1 more Smart Citation

Reflecting on Cherenkov reflections

Fargion,

Gaug,

Oliva

2007

Preprint

Self Cite

View full text Add to dashboard Cite

MAGIC, as well as HESS and VERITAS, is a Čerenkov Telescope unveiling γ-ray sources above 60 GeV at vertical within noisy (hadronic) airshowering sky. These telescopes while facing the horizons may reveal rarest blazing UHECR as well as far fluorescence tails of downward PeV-EeV hadronic airshowers. Few of these inclined airshowers blazing on axis are spread by the geomagnetic field into twin spots. These twin flashes and their morphology may tag the UHECR origination site. There is a rich window of such reflecting Čerenkov lights visible by Telescopes on top of Mountains as MAGIC (and partially VERITAS): the reflections from the nearby ground (possibly enhanced by rain or snow, ice white cover), from the Sea and from the cloudy sky; in particular, these cloudy sheets may lay above or below the observer. MAGIC looking downward to the clouds or the snow, may well reveal blazing Moliere disks diffusing Čerenkov spots (few events per night). Because of geomagnetic forces and splitting of the inclined air-shower, one should reveal for the first time (at tens PeV or above) Čerenkov airshowers whose flashes are skimming the MAGIC nearby Sea and opened into twin spots. Their morphology may tag the UHECR origination, its consequent cross-section and composition. Magic telescopes looking upward into cloudy sky may observe very rare upgoing UHE Tau, originated by UHE PeVs neutrinos skimming earth, air-showering into sky, reflecting into clouds. In particular Glashow resonant antineutrinos electron hitting into Earth electrons may lead to gauged boson W − , whose decay (inside the Earth) may produce a τ + ντ [3], which later escape and decay in air is producing Čerenkov lights; these flashes may blaze into the clouds above MAGIC as upward dot spots. The Magic energy threshold for such UHE Neutrinos showers rises to PeV values. EeV UHE tau neutrinos by guaranteed GZK UHECR secondaries [6,16], via the muon-tau flavor mixing, may skim the Earth, produce UHE tau particles whose escape in air and decay in flight may blaze Magic or reflect Čerenkov light at opposite far cloudy sky edges. Any collaboration (MAGIC,HESS,VERITAS) will be willing to dedicate cloudy time to UHECR physics since nothing else can be done in that time. These reflections may open a totally new UHECR spectroscopy while unveiling a rare, but loud Tau Neutrino astronomy [10,8].

show abstract

Air-shower spectroscopy at horizons

Cited by 12 publications

References 16 publications

Characteristics of Four Upward-Pointing Cosmic-Ray-like Events Observed with ANITA

Characteristics of Four Upward-Pointing Cosmic-Ray-like Events Observed with ANITA

Limits on the flux of tau neutrinos from 1 PeV to 3 EeV with the MAGIC telescopes

Reflecting on Cherenkov reflections

Contact Info

Product

Resources

About