Search Publications
On the Polarimetric Signature of Emerging Magnetic Loops in the Quiet Sun
Viticchié, B.
The abundance of Stokes V profiles dominated by one lobe at the locations of emergence of Ω-shaped magnetic loops is evaluated. The emergence events were found in Hinode Solar Optical Telescope/spectro-polarimeter time sequences of quiet-Sun regions. Such a study has the aim of confirming a prediction based on the basic geometrical and physical pr…
Searching for γ-Ray Blazar Candidates among the Unidentified INTEGRAL Sources
Tosti, G.; Massaro, F.; Paggi, A. +1 more
The identification of low-energy counterparts for γ-ray sources is one of the biggest challenges in modern γ-ray astronomy. Recently, we developed and successfully applied a new association method to recognize γ-ray blazar candidates that could be possible counterparts for the unidentified γ-ray sources above 100 MeV in the second Fermi Large Area…
The Herschel Filament: A Signature of the Environmental Drivers of Galaxy Evolution during the Assembly of Massive Clusters at z = 0.9
Egami, E.; Yee, H. K. C.; Gladders, M. +11 more
We have discovered a 2.5 Mpc (projected) long filament of infrared-bright galaxies connecting two of the three ~5 × 1014 M ⊙ clusters making up the RCS 2319+00 supercluster at z = 0.9. The filament is revealed in a deep Herschel Spectral and Photometric Imaging REceiver (SPIRE) map that shows 250-500 µm emission associa…
Measuring the Geometry of the Universe from Weak Gravitational Lensing behind Galaxy Groups in the HST COSMOS Survey
Koekemoer, Anton M.; Ellis, Richard; Leauthaud, Alexie +12 more
Gravitational lensing can provide pure geometric tests of the structure of spacetime, for instance by determining empirically the angular diameter distance-redshift relation. This geometric test has been demonstrated several times using massive clusters which produce a large lensing signal. In this case, matter at a single redshift dominates the l…
XMM-Newton Observation of the Very Old Pulsar J0108-1431
Manchester, R. N.; Pavlov, G. G.; Shannon, R. M. +3 more
We report on an X-ray observation of the 166 Myr old radio pulsar J0108-1431 with XMM-Newton. The X-ray spectrum can be described by a power-law model with a relatively steep photon index Γ ≈ 3 or by a combination of thermal and non-thermal components, e.g., a power-law component with fixed photon index Γ = 2 plus a blackbody component with a temp…
Black-hole-Bulge Relationship of Post-starburst Quasars at z ~ 0.3
Canalizo, Gabriela; Brotherton, Michael S.; Cales, Sabrina L. +2 more
The M BH-σ* relation has been studied extensively for local galaxies, but to date there have been scarce few direct measurements of stellar velocity dispersions for systems beyond the local universe. We investigate black hole and host galaxy properties of six "post-starburst quasars" (PSQs) at z ~ 0.3. Spectra of these object…
A Strongly Lensed Massive Ultracompact Quiescent Galaxy at z ~ 2.4 in the COSMOS/UltraVISTA Field
Franx, Marijn; Muzzin, Adam; Labbé, Ivo +14 more
We report the discovery of a massive ultracompact quiescent galaxy that has been strongly lensed into multiple images by a foreground galaxy at z = 0.960. This system was serendipitously discovered as a set of extremely Ks -bright high-redshift galaxies with red J - Ks colors using new data from the UltraVISTA YJHKs
Post-flare Ultraviolet Light Curves Explained with Thermal Instability of Loop Plasma
Orlando, S.; Reale, F.; Landi, E.
In the present work, we study the C8 flare that occurred on 2000 September 26 at 19:49 UT and observed by the Solar and Heliospheric Observatory/Solar Ultraviolet Measurement of Emitted Radiation spectrometer from the beginning of the impulsive phase to well beyond the disappearance in the X-rays. The emission first decayed progressively through e…
The Evolution of Plasma Parameters on a Coronal Source Surface at 2.3 R ⊙ during Solar Minimum
Lamy, P.; Strachan, L.; Kohl, J. L. +1 more
We analyze data from the Solar and Heliospheric Observatory to produce global maps of coronal outflow velocities and densities in the regions where the solar wind is undergoing acceleration. The maps use UV and white light coronal data obtained from the Ultraviolet Coronagraph Spectrometer and the Large Angle Spectroscopic Coronagraph, respectivel…
Hubble Space Telescope FUV Spectra of the Post-common-envelope Hyades Binary V471 Tauri
Bond, Howard E.; Sion, Edward M.; Godon, Patrick +4 more
We have carried out an analysis of the Hubble Space Telescope (HST)/STIS archival spectra of the magnetic white dwarf (WD) in the Hyades eclipsing-spectroscopic, post-common-envelope binary V471 Tauri, time resolved on the orbit and on the X-ray rotational phase of the magnetic WD. An HST/STIS spectrum obtained during primary eclipse reveals a hos…