Search Publications
Where is the Engine Hiding Its Missing Energy? Constraints from a Deep X-Ray Non-detection of the Superluminous SN 2015bn
Berger, Edo; Chornock, Ryan; Margutti, Raffaella +5 more
SN 2015bn is a nearby hydrogen-poor superluminous supernova (SLSN-I) that has been intensively observed in X-rays with the goal to detect the spindown powered emission from a magnetar engine. The early-time ultraviolet/optical/infrared (UVOIR) data fit well to the magnetar model, but require leakage of energy at late times of ≲1043 erg …
Lithium and Beryllium Isotopes with the PAMELA Experiment
Castellini, G.; Sarkar, R.; Ricci, M. +56 more
The cosmic ray (CR) lithium and beryllium (6Li, 7Li, 7Be, 9Be, 10Be) isotopic composition has been measured with the satellite-borne experiment PAMELA, which was launched into low-Earth orbit on board the Resurs-DK1 satellite on 2006 June 15. The rare lithium and beryllium isotopes in CRs are …
Mapping Circumstellar Matter with Polarized Light: The Case of Supernova 2014J in M82
Baade, Dietrich; Sparks, William B.; Wang, Lifan +11 more
Optical polarimetry is an effective way of probing the environment of a supernova for dust. We acquired linear HST ACS/WFC polarimetry in bands F475W, F606W, and F775W of the supernova (SN) 2014J in M82 at six epochs from ∼277 days to ∼1181 days after the B-band maximum. The polarization measured at day 277 shows conspicuous deviations from other …
A Deep Pulse Search in 11 Low Mass X-Ray Binaries
Messenger, C.; Wette, K.; Patruno, A.
We present a systematic coherent X-ray pulsation search in 11 low mass X-ray binaries (LMXBs). We select a relatively broad variety of LMXBs, including persistent and transient sources, spanning orbital periods between 0.3 and 17 hr. We use about 3.6 Ms of data collected by the Rossi X-Ray Timing Explorer and XMM-Newton and apply a semi-coherent s…
Coordinated Assembly of Brightest Cluster Galaxies
Conroy, Charlie; Brammer, Gabriel; Gu, Meng
Brightest Cluster Galaxies (BCGs) in massive dark matter halos are shaped by complex merging processes. We present a detailed stellar population analysis in the central region of Abell 3827 at z ∼ 0.1, including five-nucleus galaxies involved in a BCG assembly. Based on deep spectroscopy from the Multi Unit Spectroscopic Explorer, we fit the optic…
Cyclic Changes of the Sun’s Seismic Radius
Rozelot, Jean-Pierre; Kosovichev, Alexander
The questions asking whether the Sun shrinks with the solar activity and what causes this have been a subject of debate. Helioseismology provides a means to measure with high precision the radial displacement of subsurface layers, the so-called “seismic radius,” through the analysis of oscillation frequencies of surface gravity (f) modes. Here, we…
Resolving the X-Ray Obscuration in a Low-flux Observation of the Quasar PDS 456
Turner, T. J.; O'Brien, P. T.; Reeves, J. N. +5 more
Simultaneous XMM-Newton, NuSTAR, and HST observations, performed in 2017 March, of the nearby (z = 0.184) luminous quasar PDS 456 are presented. PDS 456 had a low X-ray flux compared to past observations, where the first of the two new XMM-Newton observations occurred during a pronounced dip in the X-ray light curve. The broadband X-ray spectrum i…
Simultaneous Spectral Energy Distribution and Near-infrared Interferometry Modeling of HD 142666
Monnier, John D.; Kraus, Stefan; Baron, Fabien +10 more
We present comprehensive models of the Herbig Ae star, HD 142666, which aim to simultaneously explain its spectral energy distribution (SED) and near-infrared (NIR) interferometry. Our new submilliarcsecond resolution CHARA (CLASSIC and CLIMB) interferometric observations, supplemented with archival shorter baseline data from VLTI/PIONIER and the …
Intensity-corrected Herschel Observations of Nearby Isolated Low-mass Clouds
Bourke, Tyler L.; Di Francesco, James; Myers, Philip C. +8 more
We present intensity-corrected Herschel maps at 100, 160, 250, 350, and 500 µm for 56 isolated low-mass clouds. We determine the zero-point corrections for Herschel Photodetector Array Camera and Spectrometer (PACS) and Spectral Photometric Imaging Receiver (SPIRE) maps from the Herschel Science Archive (HSA) using Planck data. Since these H…
Helium Reionization Simulations. III. The Helium Lyα Forest
Trac, Hy; La Plante, Paul; Croft, Rupert +1 more
In a previous paper we presented a new suite of hydrodynamic simulations with the aim of accurately capturing the process of helium II reionization. In this paper, we discuss the observational signatures present in the He II Lyα forest. We show that the effective optical depth of the volume-averaged τ eff alone is not sufficient for cap…