相关论文: 2021 Effective Area calibration of the Nuclear Spe…
We present the calibration of the \textit{Nuclear Spectroscopic Telescope Array} (\nustar) X-ray satellite. We used the Crab as the primary effective area calibrator and constructed a piece-wise linear spline function to modify the…
We present results from a NuSTAR observation of the Crab made at a large off-axis angle of 1.5\degree. At these angles X-rays do not pass through the optics, but rather illuminate the detectors directly due to incomplete baffling. Due to…
By characterizing the contribution of stray light to large datasets from the NuSTAR X-ray observatory collected over 2012--2017, we report a measurement of the cosmic X-ray background in the 3--20 keV energy range. These data represent…
The Crab nebula and pulsar have been widely used as a calibration source for X-ray instruments. The in-flight effective area calibration of the Reflection Grating Spectrometers (RGS) of XMM-Newton depend upon the availability of reliable…
The Crab Nebula is used by many instruments as a calibration source, in particular at high energy, where it is one of the brightest celestial object. The spectrometer INTEGRAL SPI (20 keV - 8 MeV), in operation since October 2002, offers a…
We present broadband (3 -- 78 keV) NuSTAR X-ray imaging and spectroscopy of the Crab nebula and pulsar. We show that while the phase-averaged and spatially integrated nebula + pulsar spectrum is a power-law in this energy band, spatially…
Context. The Crab nebula has been used as a celestial calibration source of the X-ray flux and spectral shape for many years by X-ray astronomy missions. However, the object is often too bright for current and future missions equipped with…
The Crab Nebula is the brightest TeV gamma-ray source in the sky and has been used for the past 25 years as a reference source in TeV astronomy, for calibration and verification of new TeV instruments. The High Altitude Water Cherenkov…
Various X-ray satellites have used the Crab as a standard candle to perform their calibrations in the past. The calibration of XMM-Newton, however, is independent of the Crab nebula, because this object has not been used to adjust spectral…
The ARGO-YBJ air shower detector monitored the Crab Nebula gamma ray emission from 2007 November to 2013 February. The integrated signal, consisting of $\sim$3.3 $\times$ 10$^5$ events,reached the statistical significance of 21.1 standard…
The Crab nebula is a supernova remnant exhibiting a highly polarized synchrotron radiation at radio and millimeter wavelengths. It is the brightest source in the microwave sky with an extension of 7 by 5 arcminutes and commonly used as a…
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…
Due to the strong and steady TeV gamma-ray emission from the Crab Nebula supernova remnant, its measured flux and energy spectrum can be used to verify the calibration and data reduction methods applied to IACT data acquired over many…
The continuum high-energy gamma-ray emission between 1 GeV and 100 TeV from the Crab Nebula has been measured for the first time in overlapping energy bands by the Fermi large-area telescope (Fermi/LAT) below ~ 100 GeV and by ground-based…
The linear polarisation of the Crab pulsar and its close environment was derived from observations with the high-speed photo-polarimeter OPTIMA at the 2.56-m Nordic Optical Telescope in the optical spectral range (400 - 750 nm). Time…
The Crab Nebula has long been the standard reference point source for very-high-energy (VHE, E $>$100 GeV) gamma-ray observatories such as VERITAS. It has enabled testing and improvement of analysis methods, validation of techniques, and…
It has been over 24 years since the iconic Crab Nebula has been visited by the high spatial resolution eye of the Hubble Space Telescope. The expanding nebula is dynamic on these timescales, with many of the outer filaments of the nebula…
Aims. We use the IBIS/ISGRI telescope on-board INTEGRAL to measure the position of the centroid of the 20-200 keV emission from the Crab region. Methods. We find that the astrometry of the IBIS telescope is affected by the temperature of…
CTA (Cherenkov Telescope Array) is the next generation ground-based observatory for gamma-ray astronomy at very-high energies. The Large-Sized Telescope prototype (LST-1) is located at the Northern site of CTA, on the Canary Island of La…
The Crab nebula is widely used as a polarization angle calibrator for single-dish radio observations because of its brightness, high degree of linear polarization, and well-known polarization angle over a wide frequency range. However, the…