Publications (37)
Energy Spectrum of Cosmic Protons and Helium Nuclei by a Hybrid Measurement at 4300 m a.s.l
B. Bartoli, P. Bernardini, X. J. Bi +97
The energy spectrum of cosmic Hydrogen and Helium nuclei has been measured, below the so-called "knee", by using a hybrid experiment with a wide field-of-view Cherenkov telescope a…
Gamma-ray Observation of the Cygnus Region in the 100 TeV Energy Region
M. Amenomori, Y. W. Bao, X. J. Bi +110
We report observations of gamma-ray emissions with energies in the 100 TeV energy region from the Cygnus region in our Galaxy. Two sources are significantly detected in the directi…
Probe of the Solar Magnetic Field Using the "Cosmic-Ray Shadow" of the Sun
M. Amenomori, X. J. Bi, D. Chen +77
We report on a clear solar-cycle variation of the Sun's shadow in the 10 TeV cosmic-ray flux observed by the Tibet air shower array during a full solar cycle from 1996 to 2009. In…
Observation of TeV Gamma Rays from the Fermi Bright Galactic Sources with the Tibet Air Shower Array
M. Amenomori, X. J. Bi, D. Chen +81
Using the Tibet-III air shower array, we search for TeV gamma-rays from 27 potential Galactic sources in the early list of bright sources obtained by the Fermi Large Area Telescope…
Potential PeVatron supernova remnant G106.3+2.7 seen in the highest-energy gamma rays
M. Amenomori, Y. W. Bao, X. J. Bi +92
Cosmic rays (protons and other atomic nuclei) are believed to gain energies of petaelectronvolts (PeV) and beyond at astrophysical particle accelerators called 'PeVatrons' inside o…
Future plan for observation of cosmic gamma rays in the 100 TeV energy region with the Tibet air shower array : physics goal and overview
M. Amenomori, X. J. Bi, D. Chen +82
The Tibet air shower array, which has an effective area of 37,000 square meters and is located at 4300 m in altitude, has been observing air showers induced by cosmic rays with ene…
Observation of gamma rays up to 320 TeV from the middle-aged TeV pulsar wind nebula HESS J1849000
M. Amenomori, S. Asano, Y. W. Bao +115
Gamma rays from HESS J1849000, a middle-aged TeV pulsar wind nebula (PWN), are observed by the Tibet air shower array and the muon detector array. The detection significance of…
Observation of the thunderstorm-related ground cosmic ray flux variations by ARGO-YBJ
B. Bartoli, P. Bernardini, X. J. Bi +70
A correlation between the secondary cosmic ray flux and the near-earth electric field intensity, measured during thunderstorms, has been found by analyzing the data of the ARGO-YBJ…
Search for Gamma Ray Bursts with the ARGO-YBJ Detector in Shower Mode
B. Bartoli, P. Bernardini, X. J. Bi +69
The ARGO-YBJ detector, located at the Yangbajing Cosmic Ray Laboratory (4300 m a. s. l., Tibet, China), was a full coverage air shower array dedicated to gamma ray astronomy and co…
EAS age determination from the study of the lateral distribution of charged particles near the shower axis with the ARGO-YBJ experiment
YBJ Collaboration, B. Bartoli, P. Bernardini +69
The ARGO-YBJ experiment, a full coverage extensive air shower (EAS) detector located at high altitude (4300 m a.s.l.) in Tibet, China, has smoothly taken data, with very high stabi…
First Detection of sub-PeV Diffuse Gamma Rays from the Galactic Disk: Evidence for Ubiquitous Galactic Cosmic Rays beyond PeV Energies
M. Amenomori, Y. W. Bao, X. J. Bi +92
We report, for the first time, the long-awaited detection of diffuse gamma rays with energies between 100 TeV and 1 PeV in the Galactic disk. Particularly, all gamma rays above 398…
Influence of Earth-Directed Coronal Mass Ejections on the Sun's Shadow Observed by the Tibet-III Air Shower Array
M. Amenomori, X. J. Bi, D. Chen +78
We examine the possible influence of Earth-directed coronal mass ejections (ECMEs) on the Sun's shadow in the 3~TeV cosmic-ray intensity observed by the Tibet-III air shower (AS) a…
4.5 years multi-wavelength observations of Mrk 421 during the ARGO-YBJ and Fermi common operation time
B. Bartoli, P. Bernardini, X. J. Bi +68
We report on the extensive multi-wavelength observations of the blazar Markarian 421 (Mrk 421) covering radio to gamma-rays, during the 4.5 year period of ARGO-YBJ and Fermi common…
The Knee of the Cosmic Hydrogen and Helium Spectrum below 1 PeV Measured by ARGO-YBJ and a Cherenkov Telescope of LHAASO
B. Bartoli, P. Bernardini, X. J. Bi +93
The measurement of cosmic ray energy spectra, in particular for individual species, is an essential approach in finding their origin. Locating the "knees" of the spectra is an impo…
Mean Interplanetary Magnetic Field Measurement Using the ARGO-YBJ Experiment
G. Aielli, C. Bacci, B. Bartoli +109
The sun blocks cosmic ray particles from outside the solar system, forming a detectable shadow in the sky map of cosmic rays detected by the ARGO-YBJ experiment in Tibet. Because t…
First Detection of Photons with Energy Beyond 100 TeV from an Astrophysical Source
M. Amenomori, Y. W. Bao, X. J. Bi +88
We report on the highest energy photons from the Crab Nebula observed by the Tibet air shower array with the underground water-Cherenkov-type muon detector array. Based on the crit…
Detection of thermal neutrons with the PRISMA-YBJ array in Extensive Air Showers selected by the ARGO-YBJ experiment
B. Bartoli, P. Bernardini, X. J. Bi +79
We report on a measurement of thermal neutrons, generated by the hadronic component of extensive air showers (EAS), by means of a small array of EN-detectors developed for the PRIS…
TeV gamma-ray survey of the Northern sky using the ARGO-YBJ detector
YBJ Collaboration, B. Bartoli, P. Bernardini +94
The ARGO-YBJ detector is an extensive air shower array that has been used to monitor the northern -ray sky at energies above 0.3 TeV from 2007 November to 2013 January. In this…
Galactic Cosmic-Ray Anisotropy in the Northern hemisphere from the ARGO-YBJ Experiment during 2008-2012
B. Bartoli, P. Bernardini, X. J. Bi +69
This paper reports on the observation of the sidereal large-scale anisotropy of cosmic rays using data collected by the ARGO-YBJ experiment over 5 years (20082012). This analysi…
Search for GeV Gamma Ray Bursts with the ARGO-YBJ Detector: Summary of Eight Years of Observations
B. Bartoli, P. Bernardini, X. J. Bi +78
The search for Gamma Ray Burst (GRB) emission in the energy range 1-100 GeV in coincidence with the satellite detection has been carried out using the Astrophysical Radiation with…
Long-term monitoring of the TeV emission from Mrk 421 with the ARGO-YBJ experiment
YBJ Collaboration, B. Bartoli, P. Bernardini +105
ARGO-YBJ is an air shower detector array with a fully covered layer of resistive plate chambers. It is operated with a high duty cycle and a large field of view. It continuously mo…
Study of the diffuse gamma-ray emission from the Galactic plane with ARGO-YBJ
B. Bartoli, P. Bernardini, X. J. Bi +78
The events recorded by ARGO-YBJ in more than five years of data collection have been analyzed to determine the diffuse gamma-ray emission in the Galactic plane at Galactic longitud…
The analog Resistive Plate Chamber detector of the ARGO-YBJ experiment
B. Bartoli, P. Bernardini, X. J. Bi +68
The ARGO-YBJ experiment has been in stable data taking from November 2007 till February 2013 at the YangBaJing Cosmic Ray Observatory (4300 m a.s.l.). The detector consists of a si…
Future plan for observation of cosmic gamma rays in the 100 TeV energy region with the Tibet air shower array : simulation and sensitivity
M. Amenomori, X. J. Bi, D. Chen +82
The Tibet air shower array, which has an effective area of 37,000 square meters and is located at 4300 m in altitude, has been observing air showers induced by cosmic rays with ene…
New estimation of the spectral index of high-energy cosmic rays as determined by the Compton-Getting anisotropy
M. Amenomori, X. J. Bi, D. Chen +82
The amplitude of the Compton-Getting (CG) anisotropy contains the power-law index of the cosmic-ray energy spectrum. Based on this relation and using the Tibet air-shower array dat…
Evaluation of the Interplanetary Magnetic Field Strength Using the Cosmic-Ray Shadow of the Sun
M. Amenomori, X. J. Bi, D. Chen +80
We analyze the Sun's shadow observed with the Tibet-III air shower array and find that the shadow's center deviates northward (southward) from the optical solar disc center in the…
On Temporal Variations of the Multi-TeV Cosmic Ray Anisotropy using the Tibet III Air Shower Array
M. Amenomori, X. J. Bi, D. Chen +82
We analyze the large-scale two-dimensional sidereal anisotropy of multi-TeV cosmic rays by Tibet Air Shower Array, with the data taken from 1999 November to 2008 December. To explo…
Search for gamma-ray emission from the Sun during solar minimum with the ARGO-YBJ experiment
B. Bartoli, P. Bernardini, X. J. Bi +70
The hadronic interaction of cosmic rays with solar atmosphere can produce high energy gamma rays. The gamma-ray luminosity is correlated both with the flux of primary cosmic rays a…
Long-term Monitoring on Mrk 501 for Its VHE gamma Emission and a Flare in October 2011
YBJ Collaboration, B. Bartoli, P. Bernardini +101
As one of the brightest active blazars in both X-ray and very high energy -ray bands, Mrk 501 is very useful for physics associated with jets from AGNs. The ARGO-YBJ experiment…
Measurement of the Gamma-Ray Energy Spectrum beyond 100 TeV from the HESS J1843033 Region
M. Amenomori, S. Asano, Y. W. Bao +113
HESS J1843033 is a very-high-energy gamma-ray source whose origin remains unidentified. This work presents, for the first time, the energy spectrum of gamma rays beyond $100\, {…
The cosmic ray proton plus helium energy spectrum measured by the ARGO-YBJ experiment in the energy range 3-300 TeV
YBJ Collaboration, B. Bartoli, P. Bernardini +70
The ARGO-YBJ experiment is a full-coverage air shower detector located at the Yangbajing Cosmic Ray Observatory (Tibet, People's Republic of China, 4300 m a.s.l.). The high altitud…
Large-scale sidereal anisotropy of multi-TeV galactic cosmic rays and the heliosphere
M. Amenomori, X. J. Bi, D. Chen +83
We develop a model anisotropy best-fitting to the two-dimensional sky-map of multi-TeV galactic cosmic ray (GCR) intensity observed with the Tibet III air shower (AS) array. By inc…
Observation of TeV gamma-rays from the unidentified source HESS J1841-055 with the ARGO-YBJ experiment
YBJ Collaboration, B. Bartoli, P. Bernardini +100
We report the observation of a very high energy γ-ray source, whose position is coincident with HESS J1841-055. This source has been observed for 4.5 years by the ARGO-YBJ experim…
Observation of TeV gamma rays from the Cygnus region with the ARGO-YBJ experiment
B. Bartoli, P. Bernardini, X. J. Bi +100
We report the observation of TeV gamma-rays from the Cygnus region using the ARGO-YBJ data collected from 2007 November to 2011 August. Several TeV sources are located in this regi…
A Monte Carlo study to measure the energy spectra of the primary cosmic-ray components at the knee using a new Tibet AS core detector array
The Tibet Asγ Collaboration, :, M. Amenomori +76
A new hybrid experiment has been started by ASγ experiment at Tibet, China, since August 2011, which consists of a low threshold burst-detector-grid (YAC-II, Yangbajing Air shower…
An Updated Search of Steady TeV Ray Point Sources in Northern Hemisphere Using the Tibet Air Shower Array
Y. Wang, X. J. Bi, S. W. Cui +45
Using the data taken from Tibet II High Density (HD) Array (1997 February-1999 September) and Tibet-III array (1999 November-2005 November), our previous northern sky survey for Te…
Identification of the TeV Gamma-ray Source ARGO J2031+4157 with the Cygnus Cocoon
YBJ Collaboration, B. Bartoli, P. Bernardini +80
The extended TeV gamma-ray source ARGO J2031+4157 (or MGRO J2031+41) is positionally consistent with the Cygnus Cocoon discovered by -LAT at GeV energies in the Cygnus super…