Search Publications
The Host Galaxies of X-Ray Quasars are Not Strong Star Formers
Hasinger, G.; Li, Y.; Owen, F. N. +4 more
We use ultradeep SCUBA-2 850 µm observations (∼0.37 mJy rms) of the 2 Ms Chandra Deep Field-North (CDF-N) and 4 Ms Chandra Deep Field-South X-ray fields to examine the amount of dusty star formation taking place in the host galaxies of high-redshift X-ray active galactic nuclei (AGNs). Supplementing with COSMOS, we measure the submillimeter …
A Connection between Plasma Conditions near Black Hole Event Horizons and Outflow Properties
Gandhi, P.; Bernardini, F.; Casella, P. +9 more
Accreting black holes are responsible for producing the fastest, most powerful outflows of matter in the universe. The formation process of powerful jets close to black holes is poorly understood, and the conditions leading to jet formation are currently hotly debated. In this paper, we report an unambiguous empirical correlation between the prope…
Deep NuSTAR and Swift Monitoring Observations of the Magnetar 1E 1841-045
An, Hongjun; Hailey, Charles J.; Kaspi, Victoria M. +15 more
We report on a 350 ks NuSTAR observation of the magnetar 1E 1841-045 taken in 2013 September. During the observation, NuSTAR detected six bursts of short duration, with T90 ≲ 1 s. An elevated level of emission tail is detected after the brightest burst, persisting for ∼1 ks. The emission showed a power-law decay with a temporal index of…
Debris Distribution in HD 95086—A Young Analog of HR 8799
Rieke, George H.; Su, Kate Y. L.; Malhotra, Renu +3 more
HD 95086 is a young early-type star that hosts (1) a 5 MJ planet at the projected distance of 56 AU revealed by direct imaging, and (2) a prominent debris disk. Here we report the detection of 69 µm crystalline olivine feature from the disk using the Spitzer/MIPS-SED data covering 55-95 µm. Due to the low resolution of the M…
Revealing δ Cephei's Secret Companion and Intriguing Past
Holl, B.; Mowlavi, N.; Roelens, M. +5 more
Classical Cepheid variable stars are crucial calibrators of the cosmic distance scale thanks to a relation between their pulsation periods and luminosities. Their archetype, δ Cephei, is an important calibrator for this relation. In this paper, we show that δ Cephei is a spectroscopic binary based on newly obtained high-precision radial velocities…
ALMA Observations of the Submillimeter Dense Molecular Gas Tracers in the Luminous Type-1 Active Nucleus of NGC 7469
Meier, David S.; Turner, Jean L.; Imanishi, Masatoshi +30 more
We present Atacama Large Millimeter/submillimeter Array (ALMA) Cycle 1 observations of the central kiloparsec region of the luminous type 1 Seyfert galaxy NGC 7469 with unprecedented high resolution (0.″5 ×0.″4 = 165 × 132 pc) at submillimeter wavelengths. Utilizing the wide bandwidth of ALMA, we simultaneously obtained HCN(4-3), HCO+(4…
The Spatial Clustering of ROSAT All-Sky Survey Active Galactic Nuclei. IV. More Massive Black Holes Reside in More Massive Dark Matter Halos
Coil, Alison L.; Husemann, Bernd; Krumpe, Mirko +3 more
This is the fourth paper in a series that reports on our investigation of the clustering properties of active galactic nuclei (AGNs) identified in the ROSAT All-Sky Survey and Sloan Digital Sky Survey (SDSS). In this paper we investigate the cause of the X-ray luminosity dependence of the clustering of broad-line, luminous AGNs at 0.16\lt z\lt 0.3…
Aeolus: A Markov Chain Monte Carlo Code for Mapping Ultracool Atmospheres. An Application on Jupiter and Brown Dwarf HST Light Curves
Schneider, Glenn; Apai, Dániel; Karalidi, Theodora +2 more
Deducing the cloud cover and its temporal evolution from the observed planetary spectra and phase curves can give us major insight into the atmospheric dynamics. In this paper, we present Aeolus, a Markov chain Monte Carlo code that maps the structure of brown dwarf and other ultracool atmospheres. We validated Aeolus on a set of unique Jupiter Hu…
Reanalysis of the Near-infrared Extragalactic Background Light Based on the IRTS Observations
Matsumoto, T.; Pyo, J.; Kim, M. G. +1 more
We reanalyze data of the near-infrared background taken by IRTS using up-to-date observational results of zodiacal light (ZL), integrated star light, and diffuse Galactic light. We confirm the existence of residual isotropic emission, which is slightly lower but almost the same as previously reported. At wavelengths longer than 2 µm, the res…
The Physical Environment of the Massive Star-forming Region W42
Dewangan, L. K.; Ojha, D. K.; Luna, A. +3 more
We present an analysis of multi-wavelength observations from various data sets and Galactic plane surveys to study the star-formation process in the W42 complex. A bipolar appearance of the W42 complex is evident due to the ionizing feedback from the O5-O6 type star in a medium that is highly inhomogeneous. The Very Large Telescope/NACO adaptive-o…