output
19912026
Showing 2018 · astro-ph.HEShow all

30 papers · 2 filters

astro-ph.HE2018★ 56 cited

Accretion geometry of the black-hole binary Cygnus X-1 from X-ray polarimetry

M. Chauvin, H. -G. Florén, M. Friis +13

Black-hole binary (BHB) systems comprise a stellar-mass black hole and a closely orbiting companion star. Matter is transferred from the companion to the black hole, forming an acc…

astro-ph.HE2018★ 15 cited

PoGO+ polarimetric constraint on the synchrotron jet emission of Cygnus X-1

Maxime Chauvin, Hans-Gustav Florén, Miranda Jackson +8

We report a polarimetric constraint on the hard X-ray synchrotron jet emission from the Cygnus X-1 black-hole binary system. The observational data were obtained using the PoGO+ ha…

astro-ph.HE2018★ 173 cited

A -ray determination of the Universe's star-formation history

LAT Collaboration, M. Ajello, K. Helgason +4

The light emitted by all galaxies over the history of the Universe produces the extragalactic background light (EBL) at ultraviolet, optical, and infrared wavelengths. The EBL is a…

astro-ph.HE2018★ 105 cited

Superluminous Supernovae from the Dark Energy Survey

C. R. Angus, M. Smith, M. Sullivan +72

We present a sample of 21 hydrogen-free superluminous supernovae (SLSNe-I), and one hydrogen-rich SLSN (SLSN-II) detected during the five-year Dark Energy Survey (DES). These SNe,…

astro-ph.HE2018★ 37 cited

Unresolved Gamma-Ray Sky through its Angular Power Spectrum

M. Ackermann, M. Ajello, L. Baldini +107

The gamma-ray sky has been observed with unprecedented accuracy in the last decade by the Fermi large area telescope (LAT), allowing us to resolve and understand the high-energy Un…

astro-ph.HE2018★ 21 cited

A Search for Optical Emission from Binary-Black-Hole Merger GW170814 with the Dark Energy Camera

Z. Doctor, R. Kessler, K. Herner +96

Binary black hole (BBH) mergers found by the LIGO and Virgo detectors are of immense scientific interest to the astrophysics community, but are considered unlikely to be sources of…

astro-ph.HE2018★ 59 cited

A comprehensive analysis of anomalous ANITA events disfavors a diffuse tau-neutrino flux origin

A. Romero-Wolf, S. A. Wissel, H. Schoorlemmer +60

Recently, the ANITA collaboration reported on two upward-going extensive air shower events consistent with a primary particle that emerges from the surface of the ice. These events…

astro-ph.HE2018★ 94 cited

Efficient Nonthermal Particle Acceleration by the Kink Instability in Relativistic Jets

E. Paulo Alves, Jonathan Zrake, Frederico Fiuza

Relativistic magnetized jets from active galaxies are among the most powerful cosmic accelerators, but their particle acceleration mechanisms remain a mystery. We present a new acc…

astro-ph.HE2018★ 39 cited

Detection of polarized gamma-ray emission from the Crab nebula with Hitomi Soft Gamma-ray Detector

Hitomi Collaboration, Felix Aharonian, Hiroki Akamatsu +191

We present the results from the Hitomi Soft Gamma-ray Detector (SGD) observation of the Crab nebula. The main part of SGD is a Compton camera, which in addition to being a spectrom…

astro-ph.HE2018★ 2 cited

Upward-Pointing Cosmic-Ray-like Events Observed with ANITA

Andres Romero-Wolf, P. W. Gorham, J. Nam +73

These proceedings address a recent publication by the ANITA collaboration of four upward- pointing cosmic-ray-like events observed in the first flight of ANITA. Three of these even…

astro-ph.HE2018★ 14 cited

Nustar view of the central region of the Perseus cluster

B. Rani, G. M. Madejski, R. F. Mushotzky +2

Located at the center of the Perseus cluster, 3C 84 is an extremely bright and nearby radio galaxy. Because of the strong diffuse thermal emission from the cluster in X-rays, the d…

astro-ph.HE2018★ 21 cited

A Detailed Study of the Most Relaxed SPT-Selected Galaxy Clusters: Cool Core and Central Galaxy Properties

M. McDonald, S. W. Allen, J. Hlavacek-Larrondo +14

We present a multi-wavelength analysis of the four most relaxed clusters in the South Pole Telescope 2500 deg^2 survey, which lie at 0.55 < z < 0.75. This study, which utilizes new…

astro-ph.HE2018★ 39 cited

VERITAS and Fermi-LAT observations of new HAWC sources

VERITAS Collaboration, A. U. Abeysekara, A. Archer +280

The HAWC (High Altitude Water Cherenkov) collaboration recently published their 2HWC catalog, listing 39 very high energy (VHE; >100~GeV) gamma-ray sources based on 507 days of obs…

astro-ph.HE2018★ 50 cited

The -ray spectrum of the core of Centaurus A as observed with H.E.S.S. and Fermi-LAT

H. E. S. S. Collaboration, H. Abdalla, A. Abramowski +249

Centaurus A (Cen A) is the nearest radio galaxy discovered as a very-high-energy (VHE; 100 GeV-100 TeV) -ray source by the High Energy Stereoscopic System (H.E.S.S.). It is a fa…

astro-ph.HE2018★ 54 cited

Multi-wavelength characterization of the blazar S5~0716+714 during an unprecedented outburst phase

MAGIC Collaboration, M. L. Ahnen, S. Ansoldi +187

The BL Lac object S5~0716+714, a highly variable blazar, underwent an impressive outburst in January 2015 (Phase A), followed by minor activity in February (Phase B). The MAGIC obs…

astro-ph.HE2018★ 37 cited

Evidence for an Optical Low-frequency Quasi-Periodic Oscillation in the Kepler Light Curve of an Active Galaxy

Krista Lynne Smith, Richard F. Mushotzky, Patricia T. Boyd +1

We report evidence for a quasi-periodic oscillation (QPO) in the optical light curve of KIC 9650712, a narrow-line Seyfert 1 galaxy in the original Kepler field. After the developm…

astro-ph.HE2018★ 32 cited

The origins of the gamma-ray flux variations of NGC 1275 based on 8 years of Fermi-LAT observations

K. Tanada, J. Kataoka, M. Arimoto +4

We present an analysis of 8 years of Fermi-LAT ( > 0.1 GeV) gamma-ray data obtained for the radio galaxy NGC 1275. The gamma-ray flux from NGC 1275 is highly variable on short (~ d…

astro-ph.HE2018★ 40 cited

A Luminous and Highly-variable Gamma-ray Flare Following the 2017 Periastron of PSR B1259-63/LS 2883

T. J. Johnson, K. S. Wood, M. Kerr +4

Three periastron passages of the PSR B125963/LS 2883 binary system, consisting of a 48 ms rotation-powered pulsar and a M Be star, have been observed by the L…

astro-ph.HE2018★ 176 cited

Search for Spatial Extension in High-Latitude Sources Detected by the Fermi Large Area Telescope

LAT Collaboration, Jonathan Biteau

We present a search for spatial extension in high-latitude () sources in recent Fermi point source catalogs. The result is the Fermi High-Latitude Extended Sources Cat…

astro-ph.HE2018★ 67 cited

Fermi-LAT observations of the 2017 September 10 solar flare

Nicola Omodei, Melissa Pesce-Rollins, Francesco Longo +2

The Fermi-Large Area Telescope (LAT) detection of the X8.2 GOES class solar flare of 2017 September 10 provides for the first time observations of a long duration high-energy gamma…

astro-ph.HE2018★ 53 cited

Einstein@Home discovers a radio-quiet gamma-ray millisecond pulsar

C. J. Clark, H. J. Pletsch, J. Wu +18

Millisecond pulsars (MSPs) are old neutron stars that spin hundreds of times per second and appear to pulsate as their emission beams cross our line of sight. To date, radio pulsat…

astro-ph.HE2018★ 137 cited

Observation of an Unusual Upward-going Cosmic-ray-like Event in the Third Flight of ANITA

P. W. Gorham, B. Rotter, P. Allison +60

We report on an upward traveling, radio-detected cosmic-ray-like impulsive event with characteristics closely matching an extensive air shower. This event, observed in the third fl…

astro-ph.HE2018★ 123 cited

The Kepler Light Curves of AGN: A Detailed Analysis

Krista Lynne Smith, Richard F. Mushotzky, Patricia T. Boyd +3

We present a comprehensive analysis of 21 light curves of Type 1 AGN from the Kepler spacecraft. First, we describe the necessity and development of a customized pipeline for treat…

astro-ph.HE2018★ 162 cited

Rapidly evolving transients in the Dark Energy Survey

M. Pursiainen, M. Childress, M. Smith +79

We present the results of a search for rapidly evolving transients in the Dark Energy Survey Supernova Programme. These events are characterized by fast light curve evolution (rise…