5
5.0
Jun 29, 2018
06/18
by
X. G. Zhu; Y. F. Nie; W. W. Zhang
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eye 5
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Using a set of modified cubic trigonometric B-splines as test functions, a new differential quadrature technique is proposed for the 1D and 2D transient advection-diffusion equations of order $\alpha\in(0,1]$. The weighted coefficients are determined via solving the system of algebraic equations with a strictly diagonally dominant tri-diagonal matrix. Then, the original equation is converted into an ordinary differential system (ODS), which is discretized by a third-order...
Topics: Numerical Analysis, Mathematics
Source: http://arxiv.org/abs/1611.01597
5
5.0
Jun 28, 2018
06/18
by
T. Sbarrato; G. Ghisellini; G. Tagliaferri; M. Perri; G. M. Madejski; D. Stern; S. E. Boggs; F. E. Christensen; W. W. Craig; C. J. Hailey; F. A. Harrison; W. W. Zhang
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eye 5
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Hard X-ray observations are crucial to study the non-thermal jet emission from high-redshift, powerful blazars. We observed two bright z>2 flat spectrum radio quasars (FSRQs) in hard X-rays to explore the details of their relativistic jets and their possible variability. S5 0014+81 (at z=3.366) and B0222+185 (at z=2.690) have been observed twice by the Nuclear Spectroscopic Telescope Array (NuSTAR) simultaneously with Swift/XRT, showing different variability behaviours. We found that NuSTAR...
Topics: Astrophysics, High Energy Astrophysical Phenomena
Source: http://arxiv.org/abs/1510.08849
7
7.0
Jun 28, 2018
06/18
by
S. Riemer-Sørensen; D. Wik; G. Madejski; S. Molendi; F. Gastaldello; F. A. Harrison; W. W. Craig; C. J. Hailey; S. E. Boggs; F. E. Christensen; D. Stern; W. W. Zhang; A. Hornstrup
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eye 7
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Line emission from dark matter is well motivated for some candidates e.g. sterile neutrinos. We present the first search for dark matter line emission in the 3-80keV range in a pointed observation of the Bullet Cluster with NuSTAR. We do not detect any significant line emission and instead we derive upper limits (95% CL) on the flux, and interpret these constraints in the context of sterile neutrinos and more generic dark matter candidates. NuSTAR does not have the sensitivity to constrain the...
Topics: Cosmology and Nongalactic Astrophysics, Astrophysics
Source: http://arxiv.org/abs/1507.01378
30
30
Jun 26, 2018
06/18
by
A. Zoghbi; J. M. Miller; D. J. Walton; F. A. Harrison; A. C. Fabian; C. S. Reynolds; S. E. Boggs; F. E. Christensen; W. Craig; C. J. Hailey; D. Stern; W. W. Zhang
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eye 30
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We report on four epochs of observations of the quasar PG 1211+143 using NuSTAR. The net exposure time is 300 ks. Prior work on this source found suggestive evidence of an 'ultra-fast outflow' (or, UFO) in the Fe K band, with a velocity of approximately 0.1c. The putative flow would carry away a high mass flux and kinetic power, with broad implications for feedback and black hole-galaxy co-evolution. NuSTAR detects PG 1211+143 out to 30 keV, meaning that the continuum is well-defined both...
Topics: Astrophysics, High Energy Astrophysical Phenomena
Source: http://arxiv.org/abs/1501.01663
3
3.0
Jun 30, 2018
06/18
by
E. V. Gotthelf; J. A. Tomsick; J. P. Halpern; J. D. Gelfand; F. A. Harrison; S. E. Boggs; F. E. Christensen; W. W. Craig; J. C. Hailey; V. M. Kaspi; D. K. Stern; W. W. Zhang
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eye 3
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We report the discovery of a 206 ms pulsar associated with the TeV gamma-ray source HESS J1640-465 using the Nuclear Spectroscopic Telescope Array (NuSTAR) X-ray observatory. PSR J1640-4631 lies within the shell-type supernova remnant (SNR) G338.3-0.0, and coincides with an X-ray point source and putative pulsar wind nebula (PWN) previously identified in XMM-Newton and Chandra images. It is spinning down rapidly with period derivative Pdot = 9.758(44)E-13, yielding a spin-down luminosity Edot =...
Topics: High Energy Astrophysical Phenomena, Astrophysics
Source: http://arxiv.org/abs/1405.0465
16
16
Jun 26, 2018
06/18
by
E. Kara; A. C. Fabian; A. M. Lohfink; M. L. Parker; D. J. Walton; S. E. Boggs; F. E. Christensen; C. J. Hailey; F. A. Harrison; G. Matt; C. S. Reynolds; D. Stern; W. W. Zhang
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eye 16
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The Narrow-line Seyfert I galaxy, 1H0707-495, has been well observed in the 0.3-10 keV band, revealing a dramatic drop in flux in the iron K alpha band, a strong soft excess, and short timescale reverberation lags associated with these spectral features. In this paper, we present the first results of a deep 250 ks NuSTAR observation of 1H0707-495, which includes the first sensitive observations above 10 keV. Even though the NuSTAR observations caught the source in an extreme low-flux state, the...
Topics: High Energy Astrophysical Phenomena, Astrophysics
Source: http://arxiv.org/abs/1501.06849
4
4.0
Jun 30, 2018
06/18
by
A. Zoghbi; E. M. Cackett; C. Reynolds; E. Kara; F. A. Harrison; A. C. Fabian; A. Lohfink; G. Matt; M. Balokovic; S. E. Boggs; F. E. Christensen; W. Craig; C. J. Hailey; D. Stern; W. W. Zhang
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eye 4
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MCG-5-23-16 is one of the first AGN where relativistic reverberation in the iron K line originating in the vicinity of the supermassive black hole was found, based on a short XMM-Newton observation. In this work, we present the results from long X-ray observations using Suzaku, XMM-Newton and NuSTAR designed to map the emission region using X-ray reverberation. A relativistic iron line is detected in the lag spectra on three different time-scales, allowing the emission from different regions...
Topics: High Energy Astrophysical Phenomena, Astrophysics
Source: http://arxiv.org/abs/1405.3674
8
8.0
Jun 29, 2018
06/18
by
E. V. Gotthelf; K. Mori; E. Aliu; J. M. Paredes; J. A. Tomsick; S. E. Boggs; F. E. Christensen; W. W. Craig; C. J. Hailey; F. A. Harrison; J. S. Hong; F. Rahoui; D. Stern; W. W. Zhang
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eye 8
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We present NuSTAR hard X-ray observations of Sh 2-104, a compact HII region containing several young massive stellar clusters (YMSCs). We have detected distinct hard X-ray sources coincident with localized VERITAS TeV emission recently resolved from the giant gamma-ray complex MGRO J2019+37 in the Cygnus region. Faint, diffuse X-ray emission coincident with the eastern YMSC in Sh2-104 is likely the result of colliding winds of component stars. Just outside the radio shell of Sh 2-104 lies 3XMM...
Topics: Astrophysics, High Energy Astrophysical Phenomena
Source: http://arxiv.org/abs/1605.03641
5
5.0
Jun 29, 2018
06/18
by
A. M. El-Batal; J. M. Miller; M. T. Reynolds; S. E. Boggs; F. E. Chistensen; W. W. Craig; F. Fuerst; C. J. Hailey; F. A. Harrison; D. K. Stern; J. Tomsick; D. J. Walton; W. W. Zhang
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eye 5
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We present the results of a NuSTAR study of the dynamically confirmed stellar-mass black hole GS 1354-645. The source was observed during its 2015 "hard" state outburst; we concentrate on spectra from two relatively bright phases. In the higher-flux observation, the broadband NuSTAR spectra reveal a clear, strong disk reflection spectrum, blurred by a degree that requires a black hole spin of a = cJ/GM^2 > 0.98 (1 sigma statistical limits only). The fits also require a high...
Topics: Astrophysics, High Energy Astrophysical Phenomena
Source: http://arxiv.org/abs/1607.00343
4
4.0
Jun 30, 2018
06/18
by
G. Matt; M. Balokovic; A. Marinucci; D. R. Ballantyne; S. E. Boggs; F. E. Christensen; A. Comastri; W. W. Craig; P. Gandhi; C. J. Hailey; F. A. Harrison; G. Madejski; K. K. Madsen; D. Stern; W. W. Zhang
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eye 4
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NuSTAR observed the bright Compton-thin, narrow line Seyfert 1 galaxy, NGC 5506, for about 56 ks. In agreement with past observations, the spectrum is well fit by a power law with Gamma~1.9, a distant reflection component and narrow ionized iron lines. A relativistically blurred reflection component is not required by the data. When an exponential high energy cutoff is added to the power law, a value of 720(+130,-190) keV (90% confidence level) is found. Even allowing for systematic...
Topics: High Energy Astrophysical Phenomena, Astrophysics
Source: http://arxiv.org/abs/1412.4541
9
9.0
Jun 29, 2018
06/18
by
C. Ricci; F. E. Bauer; P. Arevalo; S. Boggs; W. N. Brandt; F. E. Christensen; W. W. Craig; P. Gandhi; C. J. Hailey; F. A. Harrison; M. Koss; C. B. Markwardt; D. Stern; E. Treister; W. W. Zhang
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eye 9
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We present the results of five NuSTAR observations of the type 2 active galactic nucleus (AGN) in IC 751, three of which were performed simultaneously with XMM-Newton or Swift/XRT. We find that the nuclear X-ray source underwent a clear transition from a Compton-thick ($N_{\rm\,H}\simeq 2\times 10^{24}\rm\,cm^{-2}$) to a Compton-thin ($N_{\rm\,H}\simeq 4\times 10^{23}\rm\,cm^{-2}$) state on timescales of $\lesssim 3$ months, which makes IC 751 the first changing-look AGN discovered by NuSTAR....
Topics: Astrophysics, High Energy Astrophysical Phenomena, Cosmology and Nongalactic Astrophysics,...
Source: http://arxiv.org/abs/1602.00702
6
6.0
Jun 30, 2018
06/18
by
E. Kara; A. Zoghbi; A. Marinucci; D. J. Walton; A. C. Fabian; G. Risaliti; S. E. Boggs; F. E. Christensen; F. Fuerst; C. J. Hailey; F. A. Harrison; G. Matt; M. L. Parker; C. S. Reynolds; D. Stern; W. W. Zhang
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eye 6
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In the past five years, a flurry of X-ray reverberation lag measurements of accreting supermassive black holes have been made using the XMM-Newton telescope in the 0.3-10 keV energy range. In this work, we use the NuSTAR telescope to extend the lag analysis up to higher energies for two Seyfert galaxies, SWIFT J2127.4+5654 and NGC 1365. X-ray reverberation lags are due to the light travel time delays between the direct continuum emission and the reprocessed emission from the inner radii of an...
Topics: High Energy Astrophysical Phenomena, Astrophysics
Source: http://arxiv.org/abs/1410.3357
15
15
Jun 28, 2018
06/18
by
J. Chenevez; D. K. Galloway; J. J. M. in 't Zand; J. A. Tomsick; D. Barret; D. Chakrabarty; F. Fürst; S. E. Boggs; F. E. Christensen; W. W. Craig; C. J. Hailey; F. A. Harrison; P. Romano; D. Stern; W. W. Zhang
texts
eye 15
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We report on NuSTAR and Swift observations of a soft state of the neutron star low-mass X-ray binary GS 1826-24, commonly known as the "clocked" burster. The transition to the soft state was recorded in 2014 June through an increase of the 2-20 keV source intensity measured by MAXI, simultaneous with a decrease of the 15-50 keV intensity measured by Swift/BAT. The episode lasted approximately two months, after which the source returned to its usual hard state. We analyze the...
Topics: High Energy Astrophysical Phenomena, Astrophysics
Source: http://arxiv.org/abs/1509.01248
7
7.0
Jun 28, 2018
06/18
by
E. Rivers; M. Baloković; P. Arévalo; F. E. Bauer; S. E. Boggs; W. N. Brandt; M. Brightman; F. E. Christensen; W. W. Craig; P. Gandhi; C. J. Hailey; F. Harrison; M. Koss; C. Ricci; D. Stern; D. J. Walton; W. W. Zhang
texts
eye 7
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NGC 7582 is a well-studied X-ray bright Seyfert 2 with moderately heavy ($N_{\text{H}}\sim10^{23}-10^{24}$~cm$^{-2}$), highly variable absorption and strong reflection spectral features. The spectral shape changed around the year 2000, dropping in observed flux and becoming much more highly absorbed. Two scenarios have been put forth to explain this spectral change: 1) the central X-ray source partially ``shut off'' around this time, decreasing in intrinsic luminosity, with a delayed decrease...
Topics: Astrophysics, High Energy Astrophysical Phenomena
Source: http://arxiv.org/abs/1511.01951
10
10.0
Jun 27, 2018
06/18
by
B. D. Lehmer; J. B. Tyler; A. E. Hornschemeier; D. R. Wik; M. Yukita; V. Antoniou; S. Boggs; F. E. Christensen; W. W. Craig; C. J. Hailey; F. A. Harrison; T. J. Maccarone; A. Ptak; D. Stern; A. Zezas; W. W. Zhang
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eye 10
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We present nearly simultaneous Chandra and NuSTAR observations of two actively star-forming galaxies within 50 Mpc: NGC 3256 and NGC 3310. Both galaxies are detected by both Chandra and NuSTAR, which together provide the first-ever spectra of these two galaxies spanning 0.3-30 keV. The X-ray emission from both galaxies is spatially resolved by Chandra; we find that hot gas dominates the E < 1-3 keV emission while ultraluminous X-ray sources (ULXs) dominate at E > 1-3 keV. The NuSTAR...
Topics: High Energy Astrophysical Phenomena, Astrophysics, Cosmology and Nongalactic Astrophysics,...
Source: http://arxiv.org/abs/1505.00789
3
3.0
Jun 30, 2018
06/18
by
Abderahmen Zoghbi; G. Matt; J. M. Miller; A. M. Lohfink; D. J. Walton; D. R. Ballantyne; J. A. Garcia; D. Stern; M. J. Koss; D. Farrah; F. A. Harrison; S. E. Boggs; F. E. Christensen; W. Craig; C. J. Hailey; W. W. Zhang
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eye 3
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MCG-5-23-16 was targeted in early 2015 with a half mega-seconds observing campaign using NuSTAR. Here we present the spectral analysis of these datasets along with an earlier observation and study the relativistic reflection and the primary coronal source. The data show strong reflection features in the form of both narrow and broad iron lines plus a Compton reflection hump. A cutoff energy is significantly detected in all exposures. The shape of the reflection spectrum does not change in the...
Topics: Astrophysics, High Energy Astrophysical Phenomena
Source: http://arxiv.org/abs/1701.02309
15
15
Jun 27, 2018
06/18
by
G. Tagliaferri; G. Ghisellini; M. Perri; M. Hayashida; M. Balokovic; S. Covino; P. Giommi; G. M. Madejski; S. Puccetti; T. Sbarrato; S. E. Boggs; J. Chiang; F. E. Christensen; W. W. Craig; C. J. Hailey; F. A. Harrison; D. Stern; W. W. Zhang
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eye 15
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The most powerful blazars are the flat spectrum radio quasars whose emission is dominated by a Compton component peaking between a few hundred keV and a few hundred MeV. We selected two bright blazars, PKS 2149-306 at redshift z=2.345 and S5 0836+710 at z=2.172, in order to observe them in the hard X-ray band with the NuSTAR satellite. In this band the Compton component is rapidly rising almost up to the peak of the emission. Simultaneous soft-X-rays and UV-optical observations were performed...
Topics: High Energy Astrophysical Phenomena, Astrophysics
Source: http://arxiv.org/abs/1503.04848
6
6.0
Jun 30, 2018
06/18
by
J. M. Miller; J. A. Tomsick; M. Bachetti; D. Wilkins; S. E. Boggs; F. E. Chistensen; W. W. Craig; A. C. Fabian; B. W. Grefenstette; C. J. Hailey; F. A. Harrison; E. Kara; A. L. King; D. K. Stern; W. W. Zhang
texts
eye 6
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We report on an observation of the Galactic black hole candidate GRS 1739-278 during its 2014 outburst, obtained with NuSTAR. The source was captured at the peak of a rising "low/hard" state, at a flux of ~0.3 Crab. A broad, skewed iron line and disk reflection spectrum are revealed. Fits to the sensitive NuSTAR spectra with a number of relativistically blurred disk reflection models yield strong geometrical constraints on the disk and hard X-ray "corona". Two models that...
Topics: High Energy Astrophysical Phenomena, Astrophysics
Source: http://arxiv.org/abs/1411.1921
6
6.0
Jun 29, 2018
06/18
by
Abderahmen Zoghbi; J. M. Miller; A. L. King; M. C. Miller; D. Proga; T. Kallman; A. C. Fabian; F. A. Harrison; J. Kaastra; J. Raymond; C. S. Reynolds; S. E. Boggs; F. E. Christensen; W. Craig; C. J. Hailey; D. Stern; W. W. Zhang
texts
eye 6
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Disk and wind signatures are seen in the soft state of Galactic black holes, while the jet is seen in the hard state. Here we study the disk-wind connection in the $\rho$ class of variability in GRS 1915+105 using a joint NuSTAR-Chandra observation. The source shows 50 sec limit cycle oscillations. By including new information provided by the reflection spectrum, and using phase-resolved spectroscopy, we find that the change in the inner disk inferred from the blackbody emission is not matched...
Topics: Astrophysics, High Energy Astrophysical Phenomena
Source: http://arxiv.org/abs/1610.05772
7
7.0
Jun 30, 2018
06/18
by
F. Gastaldello; D. R. Wik; S. Molendi; N. J. Westergaard; A. Hornstrup; G. Madejski; D. D. M. Ferreira; S. E. Boggs; F. E. Christensen; W. W. Craig; B. W. Grefenstette; C. J. Hailey; F. A. Harrison; K. K. Madsen; D. Stern; W. W. Zhang
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eye 7
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We present the results of a 55ks NuSTAR observation of the core of the Coma Cluster. The global spectrum can be explained by thermal gas emission, with a conservative 90% upper limit to non-thermal inverse Compton (IC) emission of $5.1 \times 10^{-12}$ erg cm$^{-2}$ s$^{-1}$ in a 12 arcmin $\times$ 12 arcmin field of view . The brightness of the thermal component in this central region does not allow more stringent upper limits on the IC component when compared with non-imaging instruments with...
Topics: High Energy Astrophysical Phenomena, Astrophysics, Cosmology and Nongalactic Astrophysics
Source: http://arxiv.org/abs/1411.1573
15
15
Jun 27, 2018
06/18
by
E. Rivers; G. Risaliti; D. J. Walton; F. Harrison; P. ArÉvalo; F. E. Baur; S. E. Boggs; L. W. Brenneman; M. Brightman; F. E. Christensen; W. W. Craig; F. FÜrst; C. J. Hailey; R. C. Hickox; A. Marinucci; J. Reeves; D. Stern; W. W. Zhang
texts
eye 15
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Between July 2012 and February 2013, NuSTAR and XMM-Newton performed four long-look joint obser- vations of the type 1.8 Seyfert, NGC 1365. We have analyzed the variable absorption seen in these observations in order to characterize the geometry of the absorbing material. Two of the observations caught NGC 1365 in an unusually low absorption state, revealing complexity in the multi-layer absorber which had previously been hidden. We find the need for three distinct zones of neutral absorption...
Topics: High Energy Astrophysical Phenomena, Astrophysics
Source: http://arxiv.org/abs/1503.03109
4
4.0
Jun 30, 2018
06/18
by
D. R. Ballantyne; J. M. Bollenbacher; L. W. Brenneman; K. K. Madsen; M. Balokovic; S. E. Boggs; F. E. Christensen; W. W. Craig; P. Gandhi; C. J. Hailey; F. A. Harrison; A. M. Lohfink; A. Marinucci; C. B. Markwardt; D. Stern; D. J. Walton; W. W. Zhang
texts
eye 4
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Broad-line radio galaxies (BLRGs) are active galactic nuclei that produce powerful, large-scale radio jets, but appear as Seyfert 1 galaxies in their optical spectra. In the X-ray band, BLRGs also appear like Seyfert galaxies, but with flatter spectra and weaker reflection features. One explanation for these properties is that the X-ray continuum is diluted by emission from the jet. Here, we present two NuSTAR observations of the BLRG 3C 382 that show clear evidence that the continuum of this...
Topics: Astrophysics of Galaxies, High Energy Astrophysical Phenomena, Astrophysics
Source: http://arxiv.org/abs/1408.5281
6
6.0
Jun 29, 2018
06/18
by
M. L. Parker; J. A. Tomsick; J. A. Kennea; J. M. Miller; F. A. Harrison; D. Barret; S. E. Boggs; F. E. Christensen; W. W. Craig; A. C. Fabian; F. Fuerst; V. Grinberg; C. J. Hailey; P. Romano; D. Stern; D. J. Walton; W. W. Zhang
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eye 6
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We present results from spectral fitting of the very high state of GX~339-4 with NuSTAR and Swift. We use relativistic reflection modelling to measure the spin of the black hole and inclination of the inner disk, and find a spin of $a=0.95^{+0.02}_{-0.08}$ and inclination of $30${\deg}$\pm1$ (statistical errors). These values agree well with previous results from reflection modelling. With the exceptional sensitivity of NuSTAR at the high-energy side of the disk spectrum, we are able to...
Topics: Astrophysics, High Energy Astrophysical Phenomena
Source: http://arxiv.org/abs/1603.03777
6
6.0
Jun 29, 2018
06/18
by
F. Fuerst; V. Grinberg; J. A. Tomsick; M. Bachetti; S. E. Boggs; M. Brightman; F. E. Christensen; W. W. Craig; P. Gandhi; B. Grefenstette; C. J. Hailey; F. A. Harrison; K. K. Madsen; M. L. Parker; K. Pottschmidt; D. Stern; D. J. Walton; J. Wilms; W. W. Zhang
texts
eye 6
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We present an analysis of NuSTAR observations of a hard intermediate state of the transient black hole GX 339-4 taken in January 2015. As the source softened significantly over the course of the 1.3 d-long observation we split the data into 21 sub-sets and find that the spectrum of all of them can be well described by a power-law continuum with an additional relativistically blurred reflection component. The photon index increases from ~1.69 to ~1.77 over the course of the observation. The...
Topics: Astrophysics, High Energy Astrophysical Phenomena
Source: http://arxiv.org/abs/1604.08644
3
3.0
Jun 29, 2018
06/18
by
I. G. Hannah; B. W. Grefenstette; D. M. Smith; L. Glesener; S. Krucker; H. S. Hudson; K. K. Madsen; A. Marsh; S. M. White; A. Caspi; A. Y. Shih; F. A. Harrison; D. Stern; S. E. Boggs; F. E. Christensen; W. W. Craig; C. J. Hailey; W. W. Zhang
texts
eye 3
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We present the first observations of quiescent active regions (ARs) using NuSTAR, a focusing hard X-ray telescope capable of studying faint solar emission from high temperature and non-thermal sources. We analyze the first directly imaged and spectrally resolved X-rays above 2~keV from non-flaring ARs, observed near the west limb on 2014 November 1. The NuSTAR X-ray images match bright features seen in extreme ultraviolet and soft X-rays. The NuSTAR imaging spectroscopy is consistent with...
Topics: Astrophysics, Solar and Stellar Astrophysics
Source: http://arxiv.org/abs/1603.01069
5
5.0
Jun 30, 2018
06/18
by
M. Baloković; G. Matt; F. A. Harrison; A. Zoghbi; D. R. Ballantyne; S. E. Boggs; F. E. Christensen; W. W. Craig; C. J. Esmerian; A. C. Fabian; F. Fürst; C. J. Hailey; A. Marinucci; M. L. Parker; C. S. Reynolds; D. Stern; D. J. Walton; W. W. Zhang
texts
eye 5
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Measurements of the high-energy cut-off in the coronal continuum of active galactic nuclei have long been elusive for all but a small number of the brightest examples. We present a direct measurement of the cut-off energy in the nuclear continuum of the nearby Seyfert 1.9 galaxy MCG -05-23-016 with unprecedented precision. The high sensitivity of NuSTAR up to 79 keV allows us to clearly disentangle the spectral curvature of the primary continuum from that of its reflection component. Using a...
Topics: Astrophysics of Galaxies, High Energy Astrophysical Phenomena, Astrophysics
Source: http://arxiv.org/abs/1412.5978
14
14
Jun 27, 2018
06/18
by
F. Fuerst; K. Pottschmidt; H. Miyasaka; V. Bhalerao; M. Bachetti; S. E. Boggs; F. E. Christensen; W. W. Craig; V. Grinberg; C. J. Hailey; F. A. Harrison; J. A. Kennea; F. Rahoui; D. Stern; S. P. Tendulkar; J. A. Tomsick; D. J. Walton; J. Wilms; W. W Zhang
texts
eye 14
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We present spectral analysis of NuSTAR and Swift observations of Cep X-4 during its outburst in 2014. We observed the source once during the peak of the outburst and once during the decay, finding good agreement in the spectral shape between the observations. We describe the continuum using a powerlaw with a Fermi-Dirac cutoff at high energies. Cep X-4 has a very strong cyclotron resonant scattering feature (CRSF) around 30 keV. A simple absorption-like line with a Gaussian optical depth or a...
Topics: High Energy Astrophysical Phenomena, Astrophysics
Source: http://arxiv.org/abs/1505.02788
5
5.0
Jun 30, 2018
06/18
by
Laura Brenneman; G. Madejski; F. Fuerst; G. Matt; M. Elvis; F. A. Harrison; D. R. Ballantyne; S. E. Boggs; F. E. Christensen; W. W. Craig; A. C. Fabian; B. W. Grefenstette; C. J. Hailey; K. K. Madsen; A. Marinucci; E. Rivers; D. Stern; D. J. Walton; W. W. Zhang
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eye 5
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We have obtained a deep, simultaneous observation of the bright, nearby Seyfert galaxy IC 4329A with Suzaku and NuSTAR. Through a detailed spectral analysis, we are able to robustly separate the continuum, absorption and distant reflection components in the spectrum. The absorbing column is found to be modest at $N_H = 6 \times 10^{21}$ cm$^2$, and does not introduce any significant curvature in the Fe K band. We are able to place a strong constraint on the presence of a broadened Fe K{\alpha}...
Topics: High Energy Astrophysical Phenomena, Astrophysics
Source: http://arxiv.org/abs/1404.7486
5
5.0
Jun 30, 2018
06/18
by
G. Matt; A. Marinucci; M. Guainazzi; L. W. Brenneman; M. Elvis; A. Lohfink; P. Arevalo; S. E. Boggs; M. Cappi; F. E. Christensen; W. W. Craig; A. C. Fabian; F. Fuerst; C. J. Hailey; F. A. Harrison; M. Parker; C. S. Reynolds; D. Stern; D. J. Walton; W. W. Zhang
texts
eye 5
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We present simultaneous XMM-Newton and NuSTAR observations of the `bare' Seyfert 1 galaxy, Ark 120, a system in which ionized absorption is absent. The NuSTAR hard X-ray spectral coverage allows us to constrain different models for the excess soft X-ray emission. Among phenomenological models, a cutoff power law best explains the soft X-ray emission. This model likely corresponds to Comptonization of the accretion disk seed UV photons by a population of warm electrons: using Comptonization...
Topics: High Energy Astrophysical Phenomena, Astrophysics
Source: http://arxiv.org/abs/1401.5235
5
5.0
Jun 30, 2018
06/18
by
D. J. Walton; F. A. Harrison; B. W. Grefenstette; J. M. Miller; M. Bachetti; D. Barret; S. E. Boggs; F. E. Christensen; W. W. Craig; A. C. Fabian; F. Fuerst; C. J. Hailey; K. K. Madsen; M. L. Parker; A. Ptak; V. Rana; D. Stern; N. A. Webb; W. W. Zhang
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eye 5
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We present results from the coordinated broadband X-ray observations of the extreme ultraluminous X-ray source Holmberg IX X-1 performed by NuSTAR, XMM-Newton and Suzaku in late 2012. These observations provide the first high-quality spectra of Holmberg IX X-1 above 10 keV to date, extending the X-ray coverage of this remarkable source up to ~30 keV. Broadband observations were undertaken at two epochs, between which Holmberg IX X-1 exhibited both flux and strong spectral variability,...
Topics: Astrophysics of Galaxies, High Energy Astrophysical Phenomena, Astrophysics, Cosmology and...
Source: http://arxiv.org/abs/1402.2992
3
3.0
Jun 29, 2018
06/18
by
M. Ajello; G. Ghisellini; V. S. Paliya; D. Kocevski; G. Tagliaferri; G. Madejski; A. Rau; P. Schady; J. Greiner; F. Massaro; M. Bakolovic; R. Buehler; M. Giomi; L. Marcotulli; F. D'Ammando; D. Stern; S. E. Boggs; F. E. Christensen; W. W. Craig; C. J. Hailey; F. A. Harrison; W. W. Zhang
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eye 3
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MeV blazars are a sub--population of the blazar family, exhibiting larger--than--average jet powers, accretion luminosities and black hole masses. Because of their extremely hard X--ray continua, these objects are best studied in the X-ray domain. Here, we report on the discovery by the $Fermi$ Large Area Telescope and subsequent follow-up observations with $NuSTAR$, $Swift$ and GROND of a new member of the MeV blazar family: PMN J0641$-$0320. Our optical spectroscopy provides confirmation that...
Topics: Astrophysics, High Energy Astrophysical Phenomena, Cosmology and Nongalactic Astrophysics
Source: http://arxiv.org/abs/1602.06446
6
6.0
Jun 29, 2018
06/18
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M. Yukita; A. E. Hornschemeier; B. D. Lehmer; A. Ptak; D. R. Wik; A. Zezas; V. Antoniou; T. J. Maccarone; V. Replicon; J. B. Tyler; T. Venters; M. K. Argo; K. Bechtol; S. Boggs; F. E. Christensen; W. W. Craig; C. Hailey; F. Harrison; R. Krivonos; K. Kuntz; D. Stern; W. W. Zhang
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eye 6
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We present results from sensitive, multi-epoch NuSTAR observations of the late-type star-forming galaxy M83 (d=4.6 Mpc), which is the first investigation to spatially resolve the hard (E>10 keV) X-ray emission of this galaxy. The nuclear region and ~ 20 off-nuclear point sources, including a previously discovered ultraluminous X-ray (ULX) source, are detected in our NuSTAR observations. The X-ray hardnesses and luminosities of the majority of the point sources are consistent with hard X-ray...
Topics: Astrophysics, High Energy Astrophysical Phenomena, Astrophysics of Galaxies
Source: http://arxiv.org/abs/1604.07441
4
4.0
Jun 29, 2018
06/18
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A. Masini; A. Comastri; S. Puccetti; M. Baloković; P. Gandhi; M. Guainazzi; F. E. Bauer; S. E. Boggs; P. G. Boorman; M. Brightman; F. E. Christensen; W. W. Craig; D. Farrah; C. J. Hailey; F. A. Harrison; M. J. Koss; S. M. LaMassa; C. Ricci; D. Stern; D. J. Walton; W. W. Zhang
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Aims. We study the long-term variability of the well-known Seyfert 2 galaxy Mrk 1210 (a.k.a. UGC 4203, or the Phoenix galaxy). Methods. The source was observed by many X-ray facilities in the last 20 years. Here we present a NuSTAR observation and put the results in context of previously published observations. Results. NuSTAR observed Mrk 1210 in 2012 for 15.4 ks. The source showed Compton-thin obscuration similar to that observed by Chandra, Suzaku, BeppoSAX and XMM-Newton over the past two...
Topics: Astrophysics, High Energy Astrophysical Phenomena
Source: http://arxiv.org/abs/1609.00374
3
3.0
Jun 30, 2018
06/18
by
A. Ptak; A. Hornschemeier; A. Zezas; B. Lehmer; M. Yukita; D. Wik; V. Antoniou; M. K. Argo; L. Ballo; K. Bechtol; S. Boggs; R. Della Ceca; F. E. Christensen; W. W. Craig; C. J. Hailey; F. A. Harrison; R. Krivonos; T. J. Maccarone; D. Stern; M. Tatum; T. Venters; W. W. Zhang
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eye 3
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We report on simultaneous observations of the local starburst system Arp 299 with NuSTAR and Chandra, which provides the first resolved images of this galaxy up to energies of ~ 45 keV. Fitting the 3-40 keV spectrum reveals a column density of $N_{\rm H}$ ~ 4 x10^{24} cm^{-2}, characteristic of a Compton-thick AGN, and a 10-30 keV luminosity of 1.2x 10^{43} ergs s^{-1}. The hard X-rays detected by NuSTAR above 10 keV are centered on the western nucleus, Arp 299-B, which previous X-ray...
Topics: Astrophysics of Galaxies, High Energy Astrophysical Phenomena, Astrophysics
Source: http://arxiv.org/abs/1412.3120
4
4.0
Jun 29, 2018
06/18
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A. Masini; A. Comastri; M. Baloković; I. Zaw; S. Puccetti; D. R. Ballantyne; F. E. Bauer; S. E. Boggs; W. N. Brandt; M. Brightman; F. E. Christensen; W. W. Craig; P. Gandhi; C. J. Hailey; F. A. Harrison; M. J. Koss; G. Madejski; C. Ricci; E. Rivers; D. Stern; W. W. Zhang
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eye 4
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Aims. Study the connection between the masing disk and obscuring torus in Seyfert 2 galaxies. Methods. We present a uniform X-ray spectral analysis of the high energy properties of 14 nearby megamaser Active Galactic Nuclei observed by NuSTAR. We use a simple analytical model to localize the maser disk and understand its connection with the torus by combining NuSTAR spectral parameters with available physical quantities from VLBI mapping. Results. Most of the sources analyzed are heavily...
Topics: Astrophysics, High Energy Astrophysical Phenomena, Astrophysics of Galaxies
Source: http://arxiv.org/abs/1602.03185
7
7.0
Jun 30, 2018
06/18
by
M. L. Parker; D. R. Wilkins; A. C. Fabian; D. Grupe; T. Dauser; G. Matt; F. A. Harrison; L. Brenneman; S. E. Boggs; F. E. Christensen; W. W. Craig; L. C. Gallo; C. J. Hailey; E. Kara; S. Komossa; A. Marinucci; J. M. Miller; G. Risaliti; D. Stern; D. J. Walton; W. W. Zhang
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eye 7
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We present 3-50 keV NuSTAR observations of the AGN Mrk 335 in a very low flux state. The spectrum is dominated by very strong features at the energies of the iron line at 5-7 keV and Compton hump from 10-30 keV. The source is variable during the observation, with the variability concentrated at low energies, which suggesting either a relativistic reflection or a variable absorption scenario. In this work we focus on the reflection interpretation, making use of new relativistic reflection models...
Topics: High Energy Astrophysical Phenomena, Astrophysics
Source: http://arxiv.org/abs/1407.8223
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13
Jun 26, 2018
06/18
by
M. Brightman; M. Balokovic; D. Stern; P. Arevalo; D. R. Ballantyne; F. E. Bauer; S. E. Boggs; W. W. Craig; F. E. Christensen; A. Comastri; F. Fuerst; P. Gandhi; C. J. Hailey; F. A. Harrison; R. C. Hickox; M. Koss; S. LaMassa; S. Puccetti; E. Rivers; R. Vasudevan; D. J. Walton; W. W. Zhang
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eye 13
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The covering factor of Compton-thick obscuring material associated with the torus in active galactic nuclei (AGN) is at present best understood through the fraction of sources exhibiting Compton-thick absorption along the line of sight ($N_{H}>1.5\times10^{24}$ cm$^{-2}$) in the X-ray band, which reveals the average covering factor. Determining this Compton-thick fraction is difficult however, due to the extreme obscuration. With its spectral coverage at hard X-rays ($>$10 keV), NuSTAR is...
Topics: High Energy Astrophysical Phenomena, Astrophysics
Source: http://arxiv.org/abs/1502.07353
5
5.0
Jun 29, 2018
06/18
by
Peter G. Boorman; P. Gandhi; D. Alexander; A. Annuar; D. R. Ballantyne; F. Bauer; S. E. Boggs; W. N. Brandt; M. Brightman; F. E. Christensen; W. W. Craig; D. Farrah; C. J. Hailey; F. A. Harrison; S. F. Hoenig; M. Koss; S. M. LaMassa; A. Masini; C. Ricci; G. Risaliti; D. Stern; W. W. Zhang
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eye 5
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We analyse high-quality NuSTAR observations of the local (z = 0.011) Seyfert 2 active galactic nucleus (AGN) IC 3639, in conjunction with archival Suzaku and Chandra data. This provides the first broadband X-ray spectral analysis of the source, spanning nearly two decades in energy (0.5-30 keV). Previous X-ray observations of the source below 10 keV indicated strong reflection/obscuration on the basis of a pronounced iron fluorescence line at 6.4 keV. The hard X-ray energy coverage of NuSTAR,...
Topics: Astrophysics, High Energy Astrophysical Phenomena, Astrophysics of Galaxies
Source: http://arxiv.org/abs/1610.08997
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12
Jun 27, 2018
06/18
by
F. Fuerst; M. A. Nowak; J. A. Tomsick; J. M. Miller; S. Corbel; M. Bachetti; S. E. Boggs; F. E. Christensen; W. W. Craig; A. C. Fabian; P. Gandhi; V. Grinberg; C. J. Hailey; F. A. Harrison; E. Kara; J. A. Kennea; K. K. Madsen; K. Pottschmidt; D. Stern; D. J. Walton; J. Wilms; W. W. Zhang
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eye 12
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We present spectral analysis of five NuSTAR and Swift observations of GX 339-4 taken during a failed outburst in summer 2013. These observations cover Eddington luminosity fractions in the range ~0.9-6%. Throughout this outburst, GX 339-4 stayed in the hard state, and all five observations show similar X-ray spectra with a hard power-law with a photon index near 1.6 and significant contribution from reflection. Using simple reflection models we find unrealistically high iron abundances....
Topics: High Energy Astrophysical Phenomena, Astrophysics
Source: http://arxiv.org/abs/1506.01381
6
6.0
Jun 30, 2018
06/18
by
V. M. Kaspi; R. F. Archibald; V. Bhalerao; F. Dufour; E. V. Gotthelf; H. An; M. Bachetti; A. M. Beloborodov; S. E. Boggs; F. E. Christensen; W. W. Craig; B. W. Grefenstette; C. J. Hailey; F. A. Harrison; J. A. Kennea; C. Kouveliotou; K. K. Madsen; K. Mori; C. B. Markwardt; D. Stern; J. K. Vogel; W. W. Zhang
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eye 6
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We present the X-ray timing and spectral evolution of the Galactic Center magnetar SGR J1745-2900 for the first ~4 months post-discovery using data obtained with the Nuclear Spectroscopic Telescope Array (NuSTAR)} and Swift observatories. Our timing analysis reveals a large increase in the magnetar spin-down rate by a factor of 2.60 +/- 0.07 over our data span. We further show that the change in spin evolution was likely coincident with a bright X-ray burst observed in 2013 June by Swift, and...
Topics: High Energy Astrophysical Phenomena, Astrophysics
Source: http://arxiv.org/abs/1403.5344
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8.0
Jun 30, 2018
06/18
by
B. Luo; W. N. Brandt; D. M. Alexander; D. Stern; S. H. Teng; P. Arévalo; F. E. Bauer; S. E. Boggs; F. E. Christensen; A. Comastri; W. W. Craig; D. Farrah; P. Gandhi; C. J. Hailey; F. A. Harrison; M. Koss; P. Ogle; S. Puccetti; C. Saez; A. E. Scott; D. J. Walton; W. W. Zhang
texts
eye 8
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We report NuSTAR observations of a sample of six X-ray weak broad absorption line (BAL) quasars. These targets, at z=0.148-1.223, are among the optically brightest and most luminous BAL quasars known at z 330 times weaker than expected for typical quasars. Our results from a pilot NuSTAR study of two low-redshift BAL quasars, a Chandra stacking analysis of a sample of high-redshift BAL quasars, and a NuSTAR spectral analysis of the local BAL quasar Mrk 231 have already suggested the existence...
Topics: Astrophysics of Galaxies, High Energy Astrophysical Phenomena, Astrophysics
Source: http://arxiv.org/abs/1408.3633
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11
Jun 27, 2018
06/18
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M. L. Parker; J. A. Tomsick; J. M. Miller; K. Yamaoka; A. Lohfink; M. Nowak; A. C. Fabian; W. N. Alston; S. E. Boggs; F. E. Christensen; W. W. Craig; F. Fuerst; P. Gandhi; B. W. Grefenstette; V. Grinberg; C. J. Hailey; F. A. Harrison; E. Kara; A. L. King; D. Stern; D. J. Walton; J. Wilms; W. W. Zhang
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eye 11
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We present simultaneous Nuclear Spectroscopic Telescope Array (NuSTAR ) and Suzaku observations of the X-ray binary Cygnus X-1 in the hard state. This is the first time this state has been observed in Cyg X-1 with NuSTAR, which enables us to study the reflection and broad-band spectra in unprecedented detail. We confirm that the iron line cannot be fit with a combination of narrow lines and absorption features, and instead requires a relativistically blurred profile in combination with a narrow...
Topics: High Energy Astrophysical Phenomena, Astrophysics
Source: http://arxiv.org/abs/1506.00007
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11
Jun 26, 2018
06/18
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G. Younes; C. Kouveliotou; B. W. Grefenstette; J. A. Tomsick; A. Tennant; M. H. Finger; F. Furst; K. Pottschmidt; V. Bhalerao; S. E. Boggs; L. Boirin; D. Chakrabarty; F. E. Christensen; W. W. Craig; N. Degenaar; A. C. Fabian; P. Gandhi; E. Gogus; C. J. Hailey; F. A. Harrison; J. A. Kennea; J. M. Miller; D. Stern; W. W. Zhang
texts
eye 11
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We report on a 10 ks simultaneous Chandra/HETG-NuSTAR observation of the Bursting Pulsar, GRO J1744-28, during its third detected outburst since discovery and after nearly 18 years of quiescence. The source is detected up to 60 keV with an Eddington persistent flux level. Seven bursts, followed by dips, are seen with Chandra, three of which are also detected with NuSTAR. Timing analysis reveals a slight increase in the persistent emission pulsed fraction with energy (from 10% to 15%) up to 10...
Topics: High Energy Astrophysical Phenomena, Astrophysics
Source: http://arxiv.org/abs/1502.05982
5
5.0
Jun 30, 2018
06/18
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P. Arévalo; F. E. Bauer; S. Puccetti; D. J. Walton; M. Koss; S. E. Boggs; W. N. Brandt; M. Brightman; F. E. Christensen; A. Comastri; W. W. Craig; F. Fuerst; P. Gandhi; B. W. Grefenstette; C. J. Hailey; F. A. Harrison; B. Luo; G. Madejski; K. K. Madsen; A. Marinucci; G. Matt; C. Saez; D. Stern; M. Stuhlinger; E. Treister; C. M. Urry; W. W. Zhang
texts
eye 5
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The Circinus galaxy is one of the nearest obscured AGN, making it an ideal target for detailed study. Combining archival Chandra and XMM-Newton data with new NuSTAR observations, we model the 2-79 keV spectrum to constrain the primary AGN continuum and to derive physical parameters for the obscuring material. Chandra's high angular resolution allows a separation of nuclear and off-nuclear galactic emission. In the off-nuclear diffuse emission we find signatures of strong cold reflection,...
Topics: Astrophysics of Galaxies, High Energy Astrophysical Phenomena, Astrophysics
Source: http://arxiv.org/abs/1406.3345
4
4.0
Jun 30, 2018
06/18
by
D. J. Walton; G. Risaliti; F. A. Harrison; A. C. Fabian; J. M. Miller; P. Arevalo; D. R. Ballantyne; S. E. Boggs; L. W. Brenneman; F. E. Christensen; W. W. Craig; M. Elvis; F. Fuerst; P. Gandhi; B. W. Grefenstette; C. J. Hailey; E. Kara; B. Luo; K. K. Madsen; A. Marinucci; G. Matt; M. L. Parker; C. S. Reynolds; E. Rivers; R. R. Ross; D. Stern; W. W. Zhang
texts
eye 4
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We present a spectral analysis of four coordinated NuSTAR+XMM-Newton observations of the Seyfert galaxy NGC 1365. These exhibit an extreme level of spectral variability, which is primarily due to variable line-of-sight absorption, revealing relatively unobscured states in this source for the first time. Despite the diverse range of absorption states, each of the observations displays the same characteristic signatures of relativistic reflection from the inner accretion disk. Through...
Topics: Astrophysics of Galaxies, High Energy Astrophysical Phenomena, Astrophysics, Cosmology and...
Source: http://arxiv.org/abs/1404.5620
9
9.0
Jun 30, 2018
06/18
by
G. B. Lansbury; D. M. Alexander; A. Del Moro; P. Gandhi; R. J. Assef; D. Stern; J. Aird; D. R. Ballantyne; M. Balokovic; F. E. Bauer; S. E. Boggs; W. N. Brandt; F. E. Christensen; W. W. Craig; M. Elvis; B. W. Grefenstette; C. J. Hailey; F. A. Harrison; R. C. Hickox; M. Koss; S. M. LaMassa; B. Luo; J. R. Mullaney; S. H. Teng; C. M. Urry; W. W. Zhang
texts
eye 9
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We present NuSTAR hard X-ray (3-79 keV) observations of three Type 2 quasars at z ~ 0.4-0.5, optically selected from the Sloan Digital Sky Survey (SDSS). Although the quasars show evidence for being heavily obscured Compton-thick systems on the basis of the 2-10 keV to [OIII] luminosity ratio and multiwavelength diagnostics, their X-ray absorbing column densities (N_H) are poorly known. In this analysis: (1) we study X-ray emission at >10 keV, where X-rays from the central black hole are...
Topics: Astrophysics of Galaxies, High Energy Astrophysical Phenomena, Astrophysics
Source: http://arxiv.org/abs/1402.2666
10
10.0
Jun 29, 2018
06/18
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G. Lanzuisi; M. Perna; A. Comastri; M. Cappi; M. Dadina; A. Marinucci; A. Masini; G. Matt; F. Vagnetti; C. Vignali; D. R. Ballantyne; F. E. Bauer; S. E. Boggs; W. N. Brandt; M. Brusa; F. E. Christensen; W. W. Craig; A. C. Fabian; D. Farrah; C. J. Hailey; F. A. Harrison; B. Luo; E. Piconcelli; S. Puccetti; C. Ricci; C. Saez; D. Stern; D. J. Walton; W. W. Zhang
texts
eye 10
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PG1247+267 is one of the most luminous known quasars at $z\sim2$ and is a strongly super-Eddington accreting SMBH candidate. We obtained NuSTAR data of this intriguing source in December 2014 with the aim of studying its high-energy emission, leveraging the broad band covered by the new NuSTAR and the archival XMM-Newton data. Several measurements are in agreement with the super-Eddington scenario for PG1247+267: the soft power law ($\Gamma=2.3\pm0.1$); the weak ionized Fe emission line and a...
Topics: Astrophysics, High Energy Astrophysical Phenomena
Source: http://arxiv.org/abs/1604.02462
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6.0
Jun 30, 2018
06/18
by
Stacy H. Teng; W. N. Brandt; F. A. Harrison; B. Luo; D. M. Alexander; F. E. Bauer; S. E. Boggs; F. E. Christensen; A. Comastri; W. W. Craig; A. C. Fabian; D. Farrah; F. Fiore; P. Gandhi; B. W. Grefenstette; C. J. Hailey; R. C. Hickox; K. K. Madsen; A. F. Ptak; J. R. Rigby; G. Risaliti; C. Saez; D. Stern; S. Veilleux; D. J. Walton; D. R. Wik; W. W. Zhang
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eye 6
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We present high-energy (3--30 keV) {\it NuSTAR} observations of the nearest quasar, the ultraluminous infrared galaxy (ULIRG) Markarian 231 (Mrk 231), supplemented with new and simultaneous low-energy (0.5--8 keV) data from {\it Chandra}. The source was detected, though at much fainter levels than previously reported, likely due to contamination in the large apertures of previous non-focusing hard X-ray telescopes. The full band (0.5--30 keV) X-ray spectrum suggests the active galactic nucleus...
Topics: High Energy Astrophysical Phenomena, Astrophysics
Source: http://arxiv.org/abs/1402.4811
7
7.0
Jun 30, 2018
06/18
by
A. Del Moro; J. R. Mullaney; D. M. Alexander; A. Comastri; F. E. Bauer; E. Treister; D. Stern; F. Civano; P. Ranalli; C. Vignali; J. A. Aird; D. R. Ballantyne; M. Baloković; S. E. Boggs; W. N. Brandt; F. E. Christensen; W. W. Craig; P. Gandhi; R. Gilli; C. J. Hailey; F. A. Harrison; R. C. Hickox; S. M. LaMassa; G. B. Lansbury; B. Luo; S. Puccetti; M. Urry; W. W. Zhang
texts
eye 7
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We report NuSTAR observations of NuSTAR J033202-2746.8, a heavily obscured, radio-loud quasar detected in the Extended Chandra Deep Field-South, the deepest layer of the NuSTAR extragalactic survey (~400 ks, at its deepest). NuSTAR J033202-2746.8 is reliably detected by NuSTAR only at E>8 keV and has a very flat spectral slope in the NuSTAR energy band (Gamma=0.55^{+0.62}_{-0.64}; 3-30 keV). Combining the NuSTAR data with extremely deep observations by Chandra and XMM-Newton (4 Ms and 3 Ms,...
Topics: Astrophysics of Galaxies, Astrophysics, Cosmology and Nongalactic Astrophysics
Source: http://arxiv.org/abs/1403.2491
5
5.0
Jun 30, 2018
06/18
by
M. Baloković; A. Comastri; F. A. Harrison; D. M. Alexander; D. R. Ballantyne; F. E. Bauer; S. E. Boggs; W. N. Brandt; M. Brightman; F. E. Christensen; W. W. Craig; A. Del Moro; P. Gandhi; C. J. Hailey; M. Koss; G. B. Lansbury; B. Luo; G. M. Madejski; A. Marinucci; G. Matt; C. B. Markwardt; S. Puccetti; C. S. Reynolds; G. Risaliti; E. Rivers; D. Stern; D. J. Walton; W. W. Zhang
texts
eye 5
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We present X-ray spectral analyses for three Seyfert 2 active galactic nuclei, NGC 424, NGC 1320, and IC 2560, observed by NuSTAR in the 3-79 keV band. The high quality hard X-ray spectra allow detailed modeling of the Compton reflection component for the first time in these sources. Using quasi-simultaneous NuSTAR and Swift/XRT data, as well as archival XMM-Newton data, we find that all three nuclei are obscured by Compton-thick material with column densities in excess of ~5 x $10^{24}$...
Topics: Astrophysics of Galaxies, High Energy Astrophysical Phenomena, Astrophysics
Source: http://arxiv.org/abs/1408.5414
