THE ULTRA FAST FLASH OBSERVATORY PATHFINDER – UFFO-P GRB IMAGING AND LOCATION WITH ITS CODED MASK X-RAY IMAGER UBAT V. Reglero1

X1755-338 is an X-ray binary source which displays X-ray dips with a 4.4 hour period (White et al. 1984). It was previously noted as an unusually soft X-ray source by Jones (1977) and was suggested later as a black-hole candidate (BHC) by White & Marshall (1984), and White et al. (1984), based on the similarity of its location in an X-ray colour-colour diagram to that of a group of BHCs.The TTM is a coded-mask imaging spectrometer on board the KVANT module of the MIR space station. It is capable of producing images in the 2 – 30 keV band with an energy resolution of about 18% at 6 keV. The instrumental details are given in Brinkman et al. (1985).We observed X1755-338 in 1989 March-September during the period of the TTM Galactic Centre Survey.

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The galactic centre

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1979.0056 ◽

1979 ◽

Vol 366 (1726) ◽

pp. 345-355 ◽

Cited By ~ 2

Keyword(s):

Extended Period ◽

Galactic Centre ◽

X Ray ◽

Coded Mask

While the Uhuru satellite detected an extended or multiple X-ray source located in the direction of the galactic centre, and while transient and burst sources have been found there by Ariel 5 and SAS-3, there has not so far been any detailed description of this important source. By using results from a coded mask telescope flown in 1976 on a Skylark rocket (the first successful application of such a device in astronomy) and from an extended period of observations with Ariel 5, a number of burst and irregular variable X-ray sources have now been discovered. In particular, the region within a few degrees of the galactic centre is evidently one of continual but irregular X-ray activity.

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Techniques for the analysis of data from coded-mask X-ray telescopes

Astrophysics and Space Science ◽

10.1007/bf00642125 ◽

1987 ◽

Vol 136 (2) ◽

pp. 337-349 ◽

Cited By ~ 22

Author(s):

G. K. Skinner ◽

T. J. Ponman ◽

A. P. Hammersley ◽

C. J. Eyles

Keyword(s):

X Ray ◽

Coded Mask

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Timing Analysis with INTEGRAL: Comparing Different Reconstruction Algorithms

Acta Polytechnica ◽

10.14311/1312 ◽

2011 ◽

Vol 51 (1) ◽

Author(s):

V. Grinberg ◽

I. Kreykenbohm ◽

F. Fürst ◽

J. Wilms ◽

K. Pottschmidt ◽

...

Keyword(s):

Image Reconstruction ◽

Time Resolution ◽

Timing Analysis ◽

Light Curves ◽

X Rays ◽

Reconstruction Algorithms ◽

X Ray ◽

Coded Mask

INTEGRAL is one of the few instruments capable of detecting X-rays above 20 keV. It is therefore in principle well suited for studying X-ray variability in this regime. Because INTEGRAL uses coded mask instruments for imaging, the reconstruction of light curves of X-ray sources is highly non-trivial. We present results from a comparison of two commonly employed algorithms, which primarily measure flux from mask deconvolution (ii_lc_extract) and from calculating the pixel illuminated fraction (ii_light). Both methods agree well for timescales above about 10 s, the highest time resolution for which image reconstruction is possible. For higher time resolution, ii light produces meaningful results, although the overall variance of the lightcurves is not preserved.

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X-Ray Observations of SN1987A with a Coded Mask Imaging Spectrometer

Timing Neutron Stars ◽

10.1007/978-94-009-2273-0_27 ◽

1989 ◽

pp. 317-323

Author(s):

J. J. M. in’t Zand ◽

R. Jager ◽

J. Heise ◽

A. C. Brinkman ◽

R. A. Sunyaev ◽

...

Keyword(s):

Imaging Spectrometer ◽

X Ray ◽

Coded Mask

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The SIX survey: evolution and properties of AGN in the local universe

Proceedings of the International Astronomical Union ◽

10.1017/s174392131400355x ◽

2013 ◽

Vol 9 (S304) ◽

pp. 139-139

Author(s):

Eugenio Bottacini

Keyword(s):

Ad Hoc ◽

High Redshift ◽

Local Universe ◽

X Ray ◽

Systematic Effects ◽

Coded Mask ◽

X Ray Background ◽

Cross Calibration ◽

End Stage ◽

Calibration Techniques

AbstractCurrent most sensitive surveys at soft X-ray (~ 0.5–10 keV) energies by Chandra and XMM-Newton preferably sample AGN at high-redshift (z > 0.5). At low-redshift (z < 0.5), where AGN are supposed to be in their evolution end-stage, these sources are very sparsely sampled. The low-redshift universe is best fathomed at hard X–ray energies (> 15 keV) by the INTEGRAL and the Swift missions with their coded-mask telescopes IBIS/ISGRI and BAT respectively. These instruments have two major advantages: 1) they have a huge field of view, hence allowing to sample a large number of AGN at low-redshift; 2) they operate at energies above 15 keV, hence allowing detecting photons with enough power to efficiently pierce even through the Compton-thick torus of AGN. Estimates based on observations with PDS on board the BeppoSAX satellite predict that Compton-thick AGN should dominate over unabsorbed AGN in the local universe playing an important role in reproducing the shape and intensity of the cosmic X-ray background (CXB). However coded-mask detectors suffer from heavy systematic effects preventing them from reaching their theoretical limiting sensitivity. We overcome this limit with a new and alternative approach, which has been designed ad hoc to improve the sensitivity of hard X–ray surveys by using IBIS/ISGRI and BAT. Both telescopes are so close in design that their observations can be combined to obtain a more sensitive survey. The observations are combined with resampling, merging, and cross-calibration techniques. We are able to sample limiting fluxes of the order of ~3.3 times 10−12 erg cm−2 s−1 in the 18–55 keV energy range. This is called the SIX survey, that stands for Swift-INTEGRAL X-ray survey. The SIX survey extends over a wide sky area of 6200 deg2 and it is used to obtain a persistent sample of faint AGN. The source number density (log N - log S) is a factor of 3 better than current parent surveys of BAT and IBIS/ISGRI alone. I will present a study of the evolution of AGN in the local universe discussing the X-ray luminosity function. The properties of the AGN circum-nuclear environment will be discussed checking the consistency with the AGN unification scheme. Also I will compare the results from the SIX survey to the results predicted for the NuSTAR survey. Finally preliminary results of the all-sky SIX survey are presented.

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The design of optimum coded mask X-ray telescopes

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/187.3.633 ◽

1979 ◽

Vol 187 (3) ◽

pp. 633-643 ◽

Cited By ~ 42

Author(s):

R. J. Proctor ◽

G. K. Skinner ◽

A. P. Willmore

Keyword(s):

X Ray ◽

Coded Mask

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Irregular X-ray Variation of LMC X-3

International Astronomical Union Colloquium ◽

10.1017/s0252921100035326 ◽

1995 ◽

Vol 151 ◽

pp. 336-337

Author(s):

H.C. Pan ◽

G.K. Skinner ◽

R.A. Sunyaev ◽

N.L. Alexandrovich

Keyword(s):

Mass Transfer ◽

Energy Range ◽

Spectral Resolution ◽

Transfer Rate ◽

Mass Transfer Rate ◽

Space Station ◽

Large Magellanic Cloud ◽

Accretion Disc ◽

X Ray ◽

Coded Mask

LMC X-3 is an X-ray binary in the Large Magellanic Cloud. It was discovered by UHURU and observations with various satellites showed that the X-ray source was variable by a factor of up to 100 (e.g. Traves et al. 1988). Using the GINGA and HEAO-1 observations, Cowley et al. (1991) found a strong ∼ 198 (or possibly ∼ 99) day modulation in the X-ray luminosities of LMC X-3. They suggested that this modulation may be due to an accretion disc precession, or periodic variations in the mass transfer rate, or a combination of both.We observed LMC X-3 with the TTM in 1988-1990. The present paper gives some results from the analysis of the data obtained.The TTM is a coded mask telescope on board the MIR space station. It is capable of producing images in the energy range 2-30 keV with a spectral resolution of about 18% at 6 keV (Brinkman et al. 1985).

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