Search Publications
Scaling Relations in Coronal Mass Ejections and Energetic Proton Events Associated with Solar Superflares
Shibata, Kazunari; Takahashi, Takuya; Mizuno, Yoshiyuki
In order to discuss the potential impact of solar “superflares” on space weather, we investigated statistical relations among energetic proton peak flux with energy higher than 10 MeV (F p ), CME speed near the Sun (V CME) obtained by Solar and Heliospheric Observatory/LASCO coronagraph, and flare soft X-ray peak flux in the…
Optical Identification of Cepheids in 19 Host Galaxies of Type Ia Supernovae and NGC 4258 with the Hubble Space Telescope
Casertano, Stefano; Filippenko, Alexei V.; Foley, Ryan J. +10 more
We present results of an optical search conducted as part of the SH0ES project (Supernovae and H0 for the Equation of State of dark energy) for Cepheid variable stars using the Hubble Space Telescope (HST) in 19 hosts of Type Ia supernovae (SNe Ia) and the maser-host galaxy NGC 4258. The targets include nine newly imaged SN Ia hosts usi…
Chandra Counterparts of CANDELS GOODS-S Sources
Elbaz, D.; Shu, X.; Ferguson, H. C. +18 more
Improving the capabilities of detecting faint X-ray sources is fundamental for increasing the statistics on faint high-z active galactic nuclei (AGNs) and star-forming galaxies (SFGs). We performed a simultaneous maximum likelihood point-spread function fit in the [0.5-2] keV and [2-7] keV energy bands of the 4 Ms Chandra Deep Field South (CDFS) d…
Spectral Properties of Large Gradual Solar Energetic Particle Events. II. Systematic Q/M Dependence of Heavy Ion Spectral Breaks
McComas, D. J.; Cohen, C. M. S.; Mewaldt, R. A. +7 more
We fit ∼0.1-500 MeV nucleon-1 H-Fe spectra in 46 large solar energetic particle (SEP) events with the double power-law Band function to obtain a normalization constant, low- and high-energy parameters γ a and γ b, and break energy E B, and derive the low-energy spectral slope γ 1. We find that…
A Protosolar Nebula Origin for the Ices Agglomerated by Comet 67P/Churyumov-Gerasimenko
Wurz, P.; Altwegg, K.; Bieler, A. +10 more
The nature of the icy material accreted by comets during their formation in the outer regions of the protosolar nebula (PSN) is a major open question in planetary science. Some scenarios of comet formation predict that these bodies agglomerated from crystalline ices condensed in the PSN. Concurrently, alternative scenarios suggest that comets accr…
Kinematic Downsizing at z ∼ 2
Barro, Guillermo; Trump, Jonathan R.; Weiner, Benjamin J. +8 more
We present results from a survey of the internal kinematics of 49 star-forming galaxies at z∼ 2 in the CANDELS fields with the Keck/MOSFIRE spectrograph, Survey in the near-Infrared of Galaxies with Multiple position Angles (SIGMA). Kinematics (rotation velocity V rot and gas velocity dispersion {σ }g) are measured from nebul…
Star Formation Suppression Due to Jet Feedback in Radio Galaxies with Shocked Warm Molecular Gas
Alatalo, Katherine; Lanz, Lauranne; Ogle, Patrick M. +1 more
We present Herschel observations of 22 radio galaxies, selected for the presence of shocked, warm molecular hydrogen emission. We measured and modeled spectral energy distributions in 33 bands from the ultraviolet to the far-infrared to investigate the impact of jet feedback on star formation activity. These galaxies are massive, early-type galaxi…
The Complete Ultraviolet Spectrum of the Archetypal "Wind-dominated" Quasar Mrk 231: Absorption and Emission from a High-speed Dusty Nuclear Outflow
Veilleux, S.; Rupke, D. S. N.; Hamann, F. +2 more
New near- and far-ultraviolet (NUV and FUV) Hubble Space Telescope spectra of Mrk 231, the nearest quasar known, are combined with ground-based optical spectra to study the remarkable dichotomy between the FUV and NUV-optical spectral regions in this object. The FUV emission-line features are faint, broad, and highly blueshifted (up to ∼7000 km s<…
Observation of a Quasiperiodic Pulsation in Hard X-Ray, Radio, and Extreme-ultraviolet Wavelengths
Kumar, Pankaj; Cho, Kyung-Suk; Nakariakov, Valery M.
We present a multiwavelength analysis of a quasiperiodic pulsation (QPP) observed in the hard X-ray (HXR), radio, and extreme-ultraviolet (EUV) channels during an M1.9 flare that occurred on 2011 September 23-24. The nonthermal HXR emission in 25-50 keV observed by RHESSI shows five distinct impulsive peaks of decaying amplitude with a period of a…
The Search for Molecular Outflows in Local Volume AGNs with Herschel-PACS
Sturm, E.; Veilleux, S.; González-Alfonso, E. +3 more
We present the results from a systematic search for galactic-scale, molecular (OH 119 µm) outflows in a sample of 52 Local Volume (d\lt 50 Mpc) Burst Alert Telescope detected active galactic nuclei (BAT AGNs) with Herschel-PACS. We combine the results from our analysis of the BAT AGNs with the published Herschel/PACS data of 43 nearby (z\lt …