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Impacts of dark energy on weighing neutrinos: Mass hierarchies considered
Zhang, Xin; Wang, Sai; Wang, Yi-Fan +1 more
Taking into account the mass splittings between three active neutrinos, we investigate the impacts of dark energy on constraining the total neutrino mass ∑mν by using recent cosmological observations. We consider two typical dark energy models, namely, the w CDM model and the holographic dark energy (HDE) model, which both have an addit…
Living with a Red Dwarf: Rotation and X-Ray and Ultraviolet Properties of the Halo Population Kapteyn's Star
Guinan, Edward F.; Engle, Scott G.; Durbin, Allyn
As part of Villanova's Living with a Red Dwarf program, we have obtained UV, X-ray, and optical data of the Population II red dwarf -- Kapteyn's Star. Kapteyn's Star is noteworthy for its large proper motions and high radial velocity of ∼+245 km s-1. As the nearest Pop II red dwarf, it serves as an old age anchor for calibrating activit…
The Runaways and Isolated O-Type Star Spectroscopic Survey of the SMC (RIOTS4)
Oey, M. S.; Parker, J. Wm.; Kiminki, D. C. +4 more
We present the Runaways and Isolated O-Type Star Spectroscopic Survey of the SMC (RIOTS4), a spatially complete survey of uniformly selected field OB stars that covers the entire star-forming body of the Small Magellanic Cloud (SMC). Using the IMACS (Inamori-Magellan Areal Camera and Spectrograph) multislit spectrograph and MIKE (Magellan Inamori …
Quantifying the UV-continuum slopes of galaxies to z ∼ 10 using deep Hubble+Spitzer/IRAC observations
Wilkins, Stephen M.; Labbé, Ivo; Bouwens, Rychard J. +5 more
Measurements of the UV-continuum slopes β provide valuable information on the physical properties of galaxies forming in the early universe, probing the dust reddening, age, metal content, and even the escape fraction. While constraints on these slopes generally become more challenging at higher redshifts as the UV-continuum shifts out of the Hubb…
Relationship of EUV Irradiance Coronal Dimming Slope and Depth to Coronal Mass Ejection Speed and Mass
Vourlidas, Angelos; Colaninno, Robin C.; Woods, Thomas N. +3 more
Extreme ultraviolet (EUV) coronal dimmings are often observed in response to solar eruptive events. These phenomena can be generated via several different physical processes. For space weather, the most important of these is the temporary void left behind by a coronal mass ejection (CME). Massive, fast CMEs tend to leave behind a darker void that …
The SCUBA-2 Cosmology Legacy Survey: Multiwavelength Counterparts to 103 Submillimeter Galaxies in the UKIDSS-UDS Field
Zavala, Jorge A.; Smail, Ian; Conselice, Christopher J. +20 more
We present multiwavelength identifications for the counterparts of 1088 submillimeter sources detected at 850 µm in the SCUBA-2 Cosmology Legacy Survey study of the UKIRT Infrared Deep Sky Survey-Ultra-Deep Survey (UDS) field. By utilizing an Atacama Large Millimeter Array (ALMA) pilot study on a subset of our bright SCUBA-2 sample as a trai…
Detection of a Possible X-Ray Quasi-periodic Oscillation in the Active Galactic Nucleus 1H 0707-495
Yuan, Weimin; Zhang, Shuang-Nan; Pan, Hai-Wu +4 more
The quasi-periodic oscillation (QPO) detected in the X-ray radiation of black hole X-ray binaries (BHXBs) is thought to originate from dynamical processes in close vicinity of black holes (BHs), and thus carries important physical information therein. Such a feature is extremely rare in active galactic nuclei (AGNs) with supermassive BHs. Here we …
Two types of whistler waves in the hall reconnection region
Vaivads, A.; Retino, A.; Sahraoui, F. +13 more
Whistler waves are believed to play an important role during magnetic reconnection. Here we report the near-simultaneous occurrence of two types of the whistler-mode waves in the magnetotail Hall reconnection region. The first type is observed in the magnetic pileup region of downstream and propagates away to downstream along the field lines and i…
SKA weak lensing - I. Cosmological forecasts and the power of radio-optical cross-correlations
Zuntz, Joe; Camera, Stefano; Brown, Michael L. +1 more
We construct forecasts for cosmological parameter constraints from weak gravitational lensing surveys involving the Square Kilometre Array (SKA). Considering matter content, dark energy and modified gravity parameters, we show that the first phase of the SKA (SKA1) can be competitive with other Stage III experiments such as the Dark Energy Survey …
First identification of direct collapse black hole candidates in the early Universe in CANDELS/GOODS-S
Grazian, Andrea; Ferrara, Andrea; Fiore, Fabrizio +3 more
The first black hole seeds, formed when the Universe was younger than ∼500 Myr, are recognized to play an important role for the growth of early (z ∼ 7) supermassive black holes. While progresses have been made in understanding their formation and growth, their observational signatures remain largely unexplored. As a result, no detection of such s…