scholarly journals Characterization of the optical and X-ray properties of the north-western wisps in the Crab nebula

2013 ◽  
Vol 433 (4) ◽  
pp. 3325-3335 ◽  
Author(s):  
T. Schweizer ◽  
N. Bucciantini ◽  
W. Idec ◽  
K. Nilsson ◽  
A. Tennant ◽  
...  
Keyword(s):  
Crab Nebula ◽  
X Ray ◽  
The North ◽  
The Crab Nebula ◽  
North Western

scholarly journals New Measurement of the Vertical Atmospheric Density Profile from Occultations of the Crab Nebula with X-Ray Astronomy Satellites Suzaku and Hitomi

2020 ◽  
Author(s):  
Satoru Katsuda ◽  
Hitoshi Fujiwara ◽  
Yoshitaka Ishisaki ◽  
Yoshitomo Maeda ◽  
Koji Mori ◽  
...  
Keyword(s):  
Density Profile ◽  
Crab Nebula ◽  
Atmospheric Density ◽  
X Ray ◽  
The Crab Nebula

scholarly journals Spectral Variation of Hard X-Ray Emission from the Crab Nebula with the Suzaku Hard X-Ray Detector

2013 ◽  
Vol 65 (4) ◽  
pp. 74 ◽  
Author(s):  
Tomomi Kouzu ◽  
Makoto S. Tashiro ◽  
Yukikatsu Terada ◽  
Shin’ya Yamada ◽  
Aya Bamba ◽  
...  
Keyword(s):  
Crab Nebula ◽  
Spectral Variation ◽  
X Ray ◽  
The Crab Nebula

scholarly journals The metal artefacts from the prehistoric walled enclosure of Castelo Velho de Freixo de Numão within the early metallurgy of north-west of Iberian Peninsula

2019 ◽  
pp. 305-328
Author(s):  
Carlo Bottaini ◽  
Ignacio Montero-Ruiz ◽  
Susana Lopes ◽  
Lídia Baptista ◽  
Sérgio Gomes ◽  
...  
Keyword(s):  
Iberian Peninsula ◽  
Analytical Study ◽  
Pure Copper ◽  
X Ray ◽  
North West ◽  
The North ◽  
Metal Artefacts ◽  
Non Destructive ◽  
Arsenical Copper ◽  
North Western

This paper deals with the preliminary results of the typological and analytical study of a collection of copper-based objects found at the site of Castelo Velho (Freixo de Numão). This collection is associated to different contexts from the 3rd millennium BC (Chalcolithic). The analyses, performed by non-destructive X-ray fluorescence (XRF), show that the metals were produced with almost pure copper and arsenical copper (> 2% As). Impurities, such as As (<2%), Fe, Bi, Ag, Sn, Sb and Ni, were also identified, likely due to their presence in the ores used for the production of the objects. The data suggest that the metals from Castelo Velho may be framed within the metallurgical production already known for the Chalcolithic of the North-Western Iberian Peninsula.

scholarly journals The X-Ray Spectra of Cygnus XR-1 and the Crab Nebula

1968 ◽  
Vol 1 ◽  
pp. 202-205
Author(s):  
Laurence E. Peterson
Keyword(s):  
Power Law ◽  
Crab Nebula ◽  
Atmospheric Depth ◽  
Significance Level ◽  
X Ray ◽  
One Year ◽  
The Crab Nebula

In this paper we wish to present briefly the latest results which have been obtained on the hard X-ray spectra of two strong sources in the Northern skies. These observations, which have been discussed in detail previously (Peterson et al., 1967), were made from balloons launched at Palestine, Texas, to 3 gm/cm2 atmospheric depth during September 1966. The Crab Nebula and the Cygnus XR-1 were observed to have a differential number power law spectra with an index of about –2 over the 20–200 keV range. Both sources have the same intensity within about 10%. The Crab Nebula has been observed on two occasions, one year apart, and showed no change in intensity over this range at about a 5% significance level.

Characterization of the pelagic fish community of the north-western and northern Spanish shelf watersa

2013 ◽  
Vol 83 (4) ◽  
pp. 716-738 ◽  
Author(s):  
M. B. Santos ◽  
R. González-Quirós ◽  
I. Riveiro ◽  
M. Iglesias ◽  
M. Louzao ◽  
...  
Keyword(s):  
Fish Community ◽  
Pelagic Fish ◽  
The North ◽  
Pelagic Fish Community ◽  
North Western

scholarly journals Physical Processes and Parameters in the Magnetosphere of NP 0532

1971 ◽  
Vol 46 ◽  
pp. 394-406
Author(s):  
F. Pacini
Keyword(s):  
Neutron Star ◽  
Neutron Stars ◽  
Supernova Remnants ◽  
Crab Nebula ◽  
General Relation ◽  
Energy Generation ◽  
Main Pulse ◽  
Physical Processes ◽  
X Ray ◽  
The Crab Nebula

The Crab Nebula pulsar conforms to the model of a rotating magnetised neutron star in the rate of energy generation and the exponent of the rotation law.It is suggested that the main pulse is due to electrons and the precursor to protons. Both must radiate in coherent bunches. Optical and X-ray radiation is by the synchrotron process.The wisps observed in the Nebula may represent the release of an instability storing about 1043 erg and 1047–48 particles.Finally, some considerations are made about the general relation between supernova remnants and rotating neutron stars.

Sign in / Sign up

Export Citation Format

Share Document