Search Publications
Estimating the contribution of Galactic sources to the diffuse neutrino flux
Anchordoqui, Luis A.; Goldberg, Haim; Paul, Thomas C. +2 more
Motivated by recent IceCube observations we reexamine the idea that microquasars are high energy neutrino emitters. By stretching to the maximum the parameters of the Fermi engine we show that the nearby high-mass x-ray binary LS 5039 could accelerate protons up to above about 20 PeV. These highly relativistic protons could subsequently interact w…
Extreme Conditions in a Close Analog to the Young Solar System: Herschel Observations of epsilon Eridani
Walker, H. J.; Ivison, R. J.; Fridlund, M. +22 more
Far-infrared Herschel images of the epsilon Eridani system, seen at a fifth of the Sun's present age, resolve two belts of debris emission. Fits to the 160 µm PACS image yield radial spans for these belts of 12-16 and 54-68 AU. The south end of the outer belt is ≈10% brighter than the north end in the PACS+SPIRE images at 160, 250, and 350 &…
Statistical tests of sterile neutrinos using cosmology and short-baseline data
Bergström, Johannes; Gonzalez-Garcia, M. C.; Niro, V. +1 more
In this paper we revisit the question of the information which cosmology provides on the scenarios with sterile neutrinos invoked to describe the SBL anomalies using Bayesian statistical tests. We perform an analysis of the cosmological data in ΛCDM+ r + ν s cosmologies for different cosmological data combinations, and obtain the marg…
Multifrequency Studies of the Peculiar Quasar 4C +21.35 during the 2010 Flaring Activity
Maraschi, L.; Troja, E.; Covino, S. +289 more
The discovery of rapidly variable Very High Energy (VHE; E > 100 GeV) γ-ray emission from 4C +21.35 (PKS 1222+216) by MAGIC on 2010 June 17, triggered by the high activity detected by the Fermi Large Area Telescope (LAT) in high energy (HE; E > 100 MeV) γ-rays, poses intriguing questions on the location of the γ-ray emitting region in this f…
Higgs inflation from new Kähler potential
Choudhury, Sayantan; Pal, Supratik; Chakraborty, Trina
We introduce a new class of models of Higgs inflation using the superconformal approach to supergravity by modifying the Kähler geometry. Using the above-mentioned mechanism, we construct a phenomenological functional form of a new Kähler potential followed by construction of various types of models which are characterized by a superconformal symm…
C60 in Photodissociation Regions
Wolfire, Mark G.; Sheffer, Yaron; Berné, Olivier +2 more
Recent studies have confirmed the presence of buckminsterfullerene (C60) in different interstellar and circumstellar environments. However, several aspects regarding C60 in space are not yet well understood, such as the formation and excitation processes, and the connection between C60 and other carbonaceous compou…
Determining Heating Timescales in Solar Active Region Cores from AIA/SDO Fe XVIII Images
Warren, Harry P.; Ugarte-Urra, Ignacio
We present a study of the frequency of transient brightenings in the core of solar active regions as observed in the Fe XVIII line component of AIA/SDO 94 Å filter images. The Fe XVIII emission is isolated using an empirical correction to remove the contribution of "warm" emission to this channel. Comparing with simultaneous observations from EIS/…
Simulated Galaxy Interactions as Probes of Merger Spectral Energy Distributions
Smith, Howard A.; Hernquist, Lars; Zezas, Andreas +5 more
We present the first systematic comparison of ultraviolet-millimeter spectral energy distributions (SEDs) of observed and simulated interacting galaxies. Our sample is drawn from the Spitzer Interacting Galaxy Survey and probes a range of galaxy interaction parameters. We use 31 galaxies in 14 systems which have been observed with Herschel, Spitze…
Highly structured electron anisotropy in collisionless reconnection exhausts
Torbert, R. B.; Li, G.; Chen, L. -J. +6 more
Results from two-dimensional particle-in-cell simulations of collisionless magnetic reconnection with zero guide field discussed in this paper reveal that around the time when the reconnection rate peaks, electron velocity distributions become highly structured in magnetic islands and open exhausts. Rings, arcs, and counterstreaming beams are gene…
Water deuterium fractionation in the high-mass star-forming region G34.26+0.15 based on Herschel/HIFI data
Persson, C. M.; Lis, D. C.; Caux, E. +8 more
Understanding water deuterium fractionation is important for constraining the mechanisms of water formation in interstellar clouds. Observations of HDO and H_2^{18}O transitions were carried out towards the high-mass star-forming region G34.26+0.15 with the Heterodyne Instrument for the Far-Infrared (HIFI) instrument onboard the Herschel Space Obs…