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Temporal and Spectral Evolution in X- and γ-Rays of Magnetar 1E 1547.0-5408 since its 2008 October Outburst: The Discovery of a Transient Hard Pulsed Component after its 2009 January Outburst
Kuiper, L.; Hermsen, W.; den Hartog, P. R. +1 more
The magnetar 1E 1547.0-5408 exhibited outbursts in 2008 October and 2009 January. In this paper, we present in great detail the evolution of the temporal and spectral characteristics of the persistent total and pulsed emission of 1E 1547.0-5408 between ~1 and 300 keV starting on 2008 October 3 and ending in 2011 January. We analyzed data collected…
X-Ray Observations of the Young Pulsar J1357—6429 and Its Pulsar Wind Nebula
Pavlov, George G.; Kargaltsev, Oleg; Chang, Chulhoon +1 more
We observed the young pulsar J1357—6429 with the Chandra and XMM-Newton observatories. The pulsar spectrum fits well a combination of an absorbed power-law model (Γ = 1.7 ± 0.6) and a blackbody model (kT = 140+60 - 40 eV, R ~ 2 km at the distance of 2.5 kpc). Strong pulsations with pulsed fraction of 42% ± 5%, apparently asso…
Initiation and Development of the White-light and Radio Coronal Mass Ejection on 2001 April 15
Pick, M.; Démoulin, P.; Vourlidas, A. +1 more
The 2001 April 15 event was one of the largest of the last solar cycle. A former study established that this event was associated with a coronal mass ejection (CME) observed both at white light and radio frequencies. This radio CME is illuminated by synchrotron emission from relativistic electrons. In this paper, we investigate the relation of the…
The Faint End of the Cluster-galaxy Luminosity Function at High Redshift
Wright, Edward L.; Eisenhardt, Peter R. M.; Gonzalez, Anthony H. +7 more
We measure the faint-end slope of the galaxy luminosity function (LF) for cluster galaxies at 1 < z < 1.5 using Spitzer IRAC data. We investigate whether this slope, α, differs from that of the field LF at these redshifts, and with the cluster LF at low redshifts. The latter is of particular interest as low-luminosity galaxies are expected t…
A Significant Problem with Using the Amati Relation for Cosmological Purposes
Collazzi, Andrew C.; Schaefer, Bradley E.; Goldstein, Adam +1 more
We consider the distribution of many samples of gamma-ray bursts when plotted in a diagram with their bolometric fluence (S bolo) versus the observed photon energy of peak spectral flux (E peak, obs). In this diagram, all bursts that obey the Amati relation (a luminosity relation where the total burst energy has a power-law r…
A Detailed Morpho-kinematic Model of the Eskimo, NGC 2392: A Unifying View with the Cat's Eye and Saturn Planetary Nebulae
López, J. A.; Steffen, W.; García-Díaz, Ma. T. +1 more
The three-dimensional and kinematic structure of the Eskimo nebula, NGC 2392, has been notoriously difficult to interpret in detail given its complex morphology, multiple kinematic components and its nearly pole-on orientation along the line of sight. We present a comprehensive, spatially resolved, high-resolution, long-slit spectroscopic mapping …
The Long-term X-Ray Variability of Broad Absorption Line Quasars
Bauer, F. E.; Brandt, W. N.; Garmire, G. P. +2 more
We analyze the long-term (rest-frame 3-30 yr) X-ray variability of 11 broad absorption line (BAL) quasars, mainly to constrain the variation properties of the X-ray absorbing shielding gas that is thought to play a critical role in BAL wind launching. Our BAL quasar sample has coverage with multiple X-ray observatories including Chandra, XMM-Newto…
A Multi-epoch Timing and Spectral Study of the Ultraluminous X-Ray NGC 5408 X-1 with XMM-Newton
Pasham, Dheeraj R.; Strohmayer, Tod E.
We present results of new XMM-Newton observations of the ultraluminous X-ray source (ULX) NGC 5408 X-1, one of the few ULXs to show quasi-periodic oscillations (QPOs). We detect QPOs in each of four new (≈100 ks) pointings, expanding the range of frequencies observed from 10 to 40 mHz. We compare our results with the timing and spectral correlatio…
Contribution of the Accretion Disk, Hot Corona, and Obscuring Torus to the Luminosity of Seyfert Galaxies: INTEGRAL and Spitzer Observations
Sunyaev, R.; Krivonos, R.; Revnivtsev, M. +12 more
We estimate the relative contributions of the supermassive black hole (SMBH) accretion disk, corona, and obscuring torus to the bolometric luminosity of Seyfert galaxies, using Spitzer mid-infrared (MIR) observations of a complete sample of 68 nearby active galactic nuclei (AGNs) from the INTEGRAL all-sky hard X-ray (HX) survey. This is the first …
Why is the Solar Constant Not a Constant?
Yang, L. H.; Li, K. J.; Xu, J. C. +4 more
In order to probe the mechanism of variations of the solar constant on the inter-solar-cycle scale, the total solar irradiance (TSI; the so-called solar constant) in the time interval of 1978 November 7 to 2010 September 20 is decomposed into three components through empirical mode decomposition and time-frequency analyses. The first component is …