Search Publications
HST Follow-up Observations of Two Bright z ∼ 8 Candidate Galaxies from the BoRG Pure-parallel Survey
Treu, T.; Mason, C. A.; Trenti, M. +4 more
We present follow-up imaging of two bright (L > L*) galaxy candidates at z ≳ 8 from the Brightest of Reionizing Galaxies (BoRG) survey with the F098M filter on the Hubble Space Telescope/Wide Field Camera 3 (HST/WFC3). The F098M filter provides an additional constraint on the flux blueward of the spectral break, and the observations are designe…
The Transition from Young to Middle-aged Supernova Remnants: Thermal and Nonthermal Aspects of SNR N132D
Miller, Eric D.; Katsuda, Satoru; Terada, Yukikatsu +8 more
Supernova remnants (SNRs) are the primary candidate of Galactic cosmic-ray accelerators. It is still an open issue when and how young SNRs, which typically exhibit strong synchrotron X-rays and GeV and TeV gamma rays, undergo the state transition to middle-aged SNRs dominated by thermal X-rays and GeV gamma rays. SNR N132D in the Large Magellanic …
A High Space Density of L* Active Galactic Nuclei at z ∼ 4 in the COSMOS Field
Fiore, F.; Grazian, A.; Boutsia, K. +2 more
Identifying the source population of ionizing radiation, responsible for the reionization of the universe, is currently a hotly debated subject with conflicting results. Studies of faint, high-redshift star-forming galaxies, in most cases, fail to detect enough escaping ionizing radiation to sustain the process. Recently, the capacity of bright qu…
A Detection of Sgr A* in the Far Infrared
Fritz, Tobias K.; Ponti, Gabriele; Genzel, Reinhard +14 more
We report the first detection of the Galactic Center massive black hole, Sgr A*, at 100 µm and 160 µm. Our measurements were obtained with PACS on board the Herschel satellite. While the warm dust in the Galactic Center is too bright to allow for a direct detection of Sgr A*, we measure a significant and simultaneous variation of its f…
A Model-independent Test of Cosmic Isotropy with Low-z Pantheon Supernovae
Alcaniz, Jailson S.; Andrade, Uendert; Bengaly, Carlos A. P. +1 more
The assumption of homogeneity and isotropy on large scales is one of the main hypotheses of the standard cosmological model. In this paper, we revisit a test of cosmological isotropy using type Ia supernova (SN Ia) distances provided by the latest SN Ia compilation available, namely, the Pantheon compilation. We perform a model-independent analysi…
A Systematic Study of Hale and Anti-Hale Sunspot Physical Parameters
Li, Jing
We present a systematic study of sunspot physical parameters using full-disk magnetograms from the Michelson Doppler Imager/Solar and Heliospheric Observatory and the Helioseismic and Magnetic Imager/Solar Dynamic Observatory. Our aim is to use uniform data sets and analysis procedures to characterize the sunspots, paying particular attention to t…
Extinction Maps and Dust-to-gas Ratios in Nearby Galaxies with LEGUS
Schaerer, D.; Herrero, A.; Cignoni, M. +44 more
We present a study of the dust-to-gas ratios in five nearby galaxies: NGC 628 (M74), NGC 6503, NGC 7793, UGC 5139 (Holmberg I), and UGC 4305 (Holmberg II). Using Hubble Space Telescope broadband WFC3/UVIS UV and optical images from the Treasury program Legacy ExtraGalactic UV Survey (LEGUS) combined with archival HST/Advanced Camera for Surveys da…
The First Year of S-CUBED: The Swift Small Magellanic Cloud Survey
Coe, M. J.; Kennea, J. A.; Evans, P. A. +2 more
The Swift Small Magellanic Cloud (SMC) Survey, S-CUBED, is a high-cadence shallow X-ray survey of the SMC. The survey consists of 142 tiled pointings covering the optical extent of the SMC, which is performed weekly by NASA’s Neil Gehrels Swift Observatory, with an exposure per tile of 60 s. The survey is focused on discovery and monitoring of X-r…
RELICS: Strong-lensing Analysis of the Massive Clusters MACS J0308.9+2645 and PLCK G171.9-40.7
Ouchi, Masami; Mahler, Guillaume; Bradač, Maruša +37 more
Strong gravitational lensing by galaxy clusters has become a powerful tool for probing the high-redshift universe, magnifying distant and faint background galaxies. Reliable strong-lensing (SL) models are crucial for determining the intrinsic properties of distant, magnified sources and for constructing their luminosity function. We present here t…
Star Formation Histories of the LEGUS Dwarf Galaxies. I. Recent History of NGC 1705, NGC 4449, and Holmberg II
Cignoni, M.; Tosi, M.; Sabbi, E. +19 more
We use Hubble Space Telescope observations from the Legacy Extragalactic UV Survey to reconstruct the recent star formation histories (SFHs) of three actively star-forming dwarf galaxies, NGC 4449, Holmberg II, and NGC 1705, from their UV color-magnitude diagrams (CMDs). We apply a CMD fitting technique using two independent sets of stellar isochr…