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NuSTAR and Swift Observations of the Ultraluminous X-Ray Source IC 342 X-1 in 2016: Witnessing Spectral Evolution
Fabrika, S.; Shidatsu, M.; Ueda, Y.
We report on an X-ray observing campaign of the ultraluminous X-ray source IC 342 X-1 with NuSTAR and Swift in 2016 October, in which we captured the very moment when the source showed spectral variation. The Swift/XRT spectrum obtained in October 9-11 has a power-law shape and is consistent with those observed in the coordinated XMM-Newton and Nu…
Peering Through the Dust. II. XMM-Newton Observations of Two Additional FIRST-2MASS Red Quasars
Piconcelli, Enrico; Lacy, Mark; LaMassa, Stephanie +2 more
We obtained XMM-Newton observations of two highly luminous dust-reddened quasars, F2M1113+1244 and F2M1656+3821, that appear to be in the early, transitional phase predicted by merger-driven models of quasar/galaxy co-evolution. These sources have been well studied at optical through mid-infrared wavelengths and are growing relatively rapidly, wit…
Morphological Properties of the Crab Nebula: A Detailed Multiwavelength Study Based on New VLA, HST, Chandra, and XMM-Newton Images
Talavera, A.; Pavlov, G. G.; Kargaltsev, O. +3 more
We present a detailed analysis of the morphological properties of the Crab Nebula across the electromagnetic spectrum based on new and previous high-quality data from radio to X-rays. In the radio range we obtained an image of the entire nebula at 3 GHz with subarcsecond angular resolution using the VLA (NRAO) and an image at 100 GHz of the centra…
Improved Diffuse Foreground Subtraction with the ILC Method: CMB Map and Angular Power Spectrum Using Planck and WMAP Observations
Aluri, Pavan K.; Souradeep, Tarun; Saha, Rajib +2 more
We report an improved technique for diffuse foreground minimization from Cosmic Microwave Background (CMB) maps using a new multiphase iterative harmonic space internal-linear-combination (HILC) approach. Our method nullifies a foreground leakage that was present in the old and usual iterative HILC method. In phase 1 of the multiphase technique, w…
A Comparison of Two Methods for Estimating Black Hole Spin in Active Galactic Nuclei
Haggard, Daryl; Capellupo, Daniel M.; Wafflard-Fernandez, Gaylor
Angular momentum, or spin, is a fundamental property of black holes (BHs), yet it is much more difficult to estimate than mass or accretion rate (for actively accreting systems). In recent years, high-quality X-ray observations have allowed for detailed measurements of the Fe Kα emission line, where relativistic line broadening allows constraints …
Constraining the Physical State of the Hot Gas Halos in NGC 4649 and NGC 5846
Trinchieri, Ginevra; Romanowsky, Aaron J.; Brodie, Jean +15 more
We present results of a joint Chandra/XMM-Newton analysis of the early-type galaxies NGC 4649 and NGC 5846 aimed at investigating differences between mass profiles derived from X-ray data and those from optical data, to probe the state of the hot interstellar medium (ISM) in these galaxies. If the hot ISM is at a given radius in hydrostatic equili…
The X-Ray Reflection Spectrum of the Radio-loud Quasar 4C 74.26
Harrison, F. A.; Zhang, W. W.; Fabian, Andrew C. +11 more
The relativistic jets created by some active galactic nuclei are important agents of AGN feedback. In spite of this, our understanding of what produces these jets is still incomplete. X-ray observations, which can probe the processes operating in the central regions in the immediate vicinity of the supermassive black hole, the presumed jet launchi…
SPIRITS 15c and SPIRITS 14buu: Two Obscured Supernovae in the Nearby Star-forming Galaxy IC 2163
Tinyanont, Samaporn; Smith, Nathan; Gehrz, Robert D. +22 more
SPitzer InfraRed Intensive Transients Survey—SPIRITS—is an ongoing survey of nearby galaxies searching for infrared (IR) transients with Spitzer/IRAC. We present the discovery and follow-up observations of one of our most luminous (M [4.5] = -17.1 ± 0.4 mag, Vega) and reddest ([3.6] - [4.5] = 3.0 ± 0.2 mag) transients, SPIRITS 15c. The …
The KMOS Cluster Survey (KCS). III. Fundamental Plane of Cluster Galaxies at z ≃ 1.80 in JKCS 041
Bender, Ralf; Mendel, J. Trevor; Cappellari, Michele +12 more
We present data for 16 galaxies in the overdensity JKCS 041 at z≃ 1.80 as part of the K-band Multi-Object Spectrograph (KMOS) Cluster Survey (KCS). With 20 hr integrations, we have obtained deep absorption-line spectra from which we derived velocity dispersions for seven quiescent galaxies. We combined photometric parameters derived from Hubble Sp…
First Weak-lensing Results from “See Change”: Quantifying Dark Matter in the Two z ≳ 1.5 High-redshift Galaxy Clusters SPT-CL J2040-4451 and IDCS J1426+3508
Eisenhardt, Peter; Brodwin, Mark; Perlmutter, Saul +4 more
We present a weak-lensing study of SPT-CL J2040-4451 and IDCS J1426+3508 at z = 1.48 and 1.75, respectively. The two clusters were observed in our “See Change” program, a Hubble Space Telescope survey of 12 massive high-redshift clusters aimed at high-z supernova measurements and weak-lensing estimation of accurate cluster masses. We detect weak b…