Related papers: The Detection of TeV Gamma Rays from Crab using th…
The HEGRA collaboration has achieved outstanding results during the operation of the six imaging atmospheric Cherenkov telescopes from 1996 to 2002. The experimental work pioneered the field of TeV gamma-ray astronomy with observations…
The Crab Nebula was detected with the Milagro experiment at a statistical significance of 17 standard deviations over the lifetime of the experiment. The experiment was sensitive to approximately 100 GeV - 100 TeV gamma ray air showers by…
Between March 16, 1997 and April 14, 1997, a high flux level of TeV gamma-rays was observed from Mkn 501, using the HEGRA stereoscopic system of four imaging Cherenkov telescopes. The flux level varied during this period from about one half…
The CANGAROO experiment has observed gamma-ray above 7TeV from the Crab pulsar/nebula at large zenith angle in Woomera, South Australia. We report the CANGAROO data taken in 1992, 1993 and 1995, from which it appears that the energy…
During 1997, the BL Lac Object Mkn 501 was the brightest known object in the TeV gamma-ray sky. The emission was characterized by dramatic variations in intensity with a mean flux exceeding by a factor of three the steady gamma-ray flux of…
The well known Crab Nebula is at the center of the SN1054 supernova remnant. It consists of a rotationally-powered pulsar interacting with a surrounding nebula through a relativistic particle wind. The emissions originating from the pulsar…
We report on the first detection of very high-energy (VHE) gamma-ray emission from the Crab Nebula by a Cherenkov telescope in dual-mirror Schwarzschild-Couder (SC) configuration. The result has been achieved by means of the 4 m size…
Data taken with the HEGRA (High Energy Gamma Ray Astronomy) air shower array on La Palma is used to search for an excess of TeV $\gamma$-rays from nearby AGN. We report on the detection of two blazars (Mrk 421 and Mrk 501) with the two…
A detection of Gamma-rays from Mkn 421 at energies above 1 TeV is reported, based on observations made in December 1994 - May 1995 with the first two HEGRA Cherenkov telescopes. >From the image analysis, 111 excess gamma candidates are…
Slightly more than 30 years ago, Whipple detection of the Crab Nebula was the start of Very High Energy gamma-ray astronomy. Since then, gamma-ray observations of this source have continued to provide new surprises and challenges to…
We present the first strong detection of very high energy gamma-rays from the close (z=0.048) X-ray selected BL Lacertae object 1ES1959+650. Observations were made with the Whipple 10m telescope on Mt. Hopkins, Arizona, using the…
We spectrally fit the GeV gamma-ray flares recently-observed in the Crab Nebula by considering a small blob Lorentz-boosted towards us. We point out that the corresponding inverse-Compton flare at TeV--PeV region is more enhanced than…
The ARGO-YBJ experiment is an extensive air shower array with full coverage RPC detectors located at Yangbajing (4300 m asl, Tibet, China). It is operated with high duty cycle (>86%) and a large field of view ($\sim$ 2sr). It continuously…
The Crab nebula was once considered to be a stable source until strong flares, up to 30 times increase in flux, were observed in the MeV and GeV energy range by the AGILE and Fermi Gamma-ray Observatories. Existing nebula models often…
We report a possible detection of TeV gamma-rays from the Galactic Center by the Whipple 10m gamma-ray telescope. Twenty-six hours of data were taken over an extended period from 1995 through 2003 resulting in a total significance of 3.7…
Milagro is a water Cherenkov extensive air shower array that continuously monitors the entire overhead sky in the TeV energy band. The results from an analysis of $\sim$3 years of data (December 2000 through November 2003) are presented.…
Since February 1997 the BL Lac object Mkn 501 is in a ``high state'' of gamma-ray emission. The HEGRA collaboration has studied Mkn 501 with their air Cherenkov telescopes on La Palma. Here we report on observations with the 5 m^2 telescope…
We present results from daily monitoring of gamma rays in the energy range $\sim0.5$ to $\sim100$ TeV with the first 17 months of data from the High Altitude Water Cherenkov (HAWC) Observatory. Its wide field of view of 2 steradians and…
Routine observations of the Crab Nebula for a total of about 250 hrs, performed with the HEGRA stereoscopic system of 5 imaging atmospheric Cerenkov telescopes in the standard operational mode, have proven the energy threshold of the system…
HAGAR is a system of seven Non-imaging Atmospheric Cherenkov Telescopes located at Hanle in the Ladakh region of the Indian Himalayas at an altitude of 4270 meters {\it amsl}. Since 2008, we have observed the Crab Nebula to assess the…