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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…
Models of the Hydrodynamic Histories of Post-AGB Stars. I. Multiflow Shaping of OH 231.8+04.2
Frank, Adam; Balick, Bruce; Liu, Baowei +1 more
We present a detailed hydrodynamic model that matches the present structure of the well-observed preplanetary nebula (“pPN”) OH 231.8+04.2 (“OH231”). The purpose of the model is to present a physically justified and coherent picture of its evolutionary history from about 100 years from the start of the formation of its complex outer structures to …
Variable Stars in Local Group Galaxies. III. And VII, NGC 147, and NGC 185: Insight into the Building Blocks of the M31 Halo
Stetson, P. B.; Bono, G.; Fiorentino, G. +5 more
We present the discovery of 1568 RR Lyrae stars in three of the most luminous M31 satellites: And VII (573), NGC 147 (177), and NGC 185 (818). We use their properties to study the formation history of Local Group spiral haloes, and in particular, to infer about the nature of their possible building blocks by comparison with available data for RR L…
The Molecular Cloud S242: Physical Environment and Star-formation Activities
Dewangan, L. K.; Ojha, D. K.; Janardhan, P. +3 more
We present a multi-wavelength study to probe the star-formation (SF) processes on a larger scale (∼ 1\buildrel{\circ}\over{.} 05× 0\buildrel{\circ}\over{.} 56) around the S242 site. The S242 molecular cloud is depicted in a velocity range from -3.25 to 4.55 km s-1 and has a spatially elongated appearance. Based on the virial analysis, t…
ZFIRE: Similar Stellar Growth in Hα-emitting Cluster and Field Galaxies at z ~ 2
Papovich, Casey; Kewley, Lisa J.; Kacprzak, Glenn G. +13 more
We compare galaxy scaling relations as a function of environment at z∼ 2 with our ZFIRE survey12 where we have measured Hα fluxes for 90 star-forming galaxies selected from a mass-limited ({log}({M}\star /{M}⊙ )> 9) sample based on ZFOURGE.13 The cluster galaxies (37) are part of a confirmed system at…
A Catalog Sample of Low-mass Galaxies Observed in X-Rays with Central Candidate Black Holes
Nucita, A. A.; De Paolis, F.; Ingrosso, G. +2 more
We present a sample of X-ray-selected candidate black holes in 51 low-mass galaxies with z ≤ 0.055 and masses up to 1010 M ⊙ obtained by cross-correlating the NASA-SLOAN Atlas with the 3XMM catalog. We have also searched in the available catalogs for radio counterparts of the black hole candidates and find that 19 of the prev…
AGILE Observations of the Gravitational-wave Source GW170817: Constraining Gamma-Ray Emission from an NS-NS Coalescence
Antonelli, L. A.; Costa, E.; Barbiellini, G. +39 more
The LIGO-Virgo Collaboration (LVC) detected, on 2017 August 17, an exceptional gravitational-wave (GW) event temporally consistent within ∼ 1.7 {{s}} with the GRB 1708117A observed by Fermi-GBM and INTEGRAL. The event turns out to be compatible with a neutron star-neutron star (NS-NS) coalescence that subsequently produced a radio/optical/X-ray tr…