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On the Enhanced Coronal Mass Ejection Detection Rate since the Solar Cycle 23 Polar Field Reversal
DOI: 10.1088/0004-637X/812/1/74 Bibcode: 2015ApJ...812...74P

Petrie, G. J. D.

Compared to cycle 23, coronal mass ejections (CMEs) with angular widths >30° have been observed to occur at a higher rate during solar cycle 24, per sunspot number. This result is supported by data from three independent databases constructed using Large Angle and Spectrometric Coronagraph Experiment coronagraph images, two employing automated …

2015 The Astrophysical Journal
SOHO 20
Spectrum of Relativistic and Subrelativistic Cosmic Rays in the 100 pc Central Region
DOI: 10.1088/0004-637X/809/1/48 Bibcode: 2015ApJ...809...48D

Cheng, K. S.; Hui, C. Y.; Nobukawa, M. +6 more

From the rate of hydrogen ionization and the gamma-ray flux, we derived the spectrum of relativistic and subrelativistic cosmic rays (CRs) nearby and inside the molecular cloud Sgr B2 near the Galactic Center. We studied two cases of CR propagation in molecular clouds: free propagation and scattering of particles by magnetic fluctuations excited b…

2015 The Astrophysical Journal
INTEGRAL 20
Panchromatic Hubble Andromeda Treasury. XIV. The Period-Age Relationship of Cepheid Variables in M31 Star Clusters
DOI: 10.1088/0004-637X/813/1/31 Bibcode: 2015ApJ...813...31S

Williams, Benjamin F.; Johnson, L. Clifton; Dolphin, Andrew +6 more

We present a sample of 11 M31 Cepheids in stellar clusters, derived from the overlap of the Panchromatic Hubble Andromeda Treasury cluster catalog and the Pan-STARRS1 (PS1) disk Cepheid catalog. After identifying the PS1 Cepheids in the Hubble Space Telescope (HST) catalog, we calibrate the PS1 mean magnitudes using the higher resolution HST photo…

2015 The Astrophysical Journal
eHST 20
Dispersal of G-band Bright Points at Different Longitudinal Magnetic Field Strengths
DOI: 10.1088/0004-637X/810/2/88 Bibcode: 2015ApJ...810...88Y

Yang, Yunfei; Feng, Song; Wang, Feng +3 more

G-band bright points (GBPs) are thought to be the foot-points of magnetic flux tubes. The aim of this paper is to investigate the relation between the diffusion regimes of GBPs and the associated longitudinal magnetic field strengths. Two high resolution observations of different magnetized environments were acquired with the Hinode/Solar Optical …

2015 The Astrophysical Journal
Hinode 20
Evolution of Intermittency in the Slow and Fast Solar Wind beyond the Ecliptic Plane
DOI: 10.1088/2041-8205/814/2/L19 Bibcode: 2015ApJ...814L..19W

Bruno, R.; Wawrzaszek, A.; Macek, W. M. +1 more

We study intermittency as a departure from self-similarity of the solar wind magnetic turbulence and investigate the evolution with the heliocentric distance and latitude. We use data from the Ulysses spacecraft measured during two solar minima (1997-1998 and 2007-2008) and one solar maximum (1999-2001). In particular, by modeling a multifractal s…

2015 The Astrophysical Journal
Ulysses 20
Brightest X-Ray Clusters of Galaxies in the CFHTLS Wide Fields: Catalog and Optical Mass Estimator
DOI: 10.1088/0004-637X/799/1/60 Bibcode: 2015ApJ...799...60M

Finoguenov, A.; Tanaka, M.; Egami, E. +13 more

The Canada-France-Hawaii Telescope Legacy Survey (CFHTLS) presents a unique data set for weak-lensing studies, having high-quality imaging and deep multiband photometry. We have initiated an XMM-CFHTLS project to provide X-ray observations of the brightest X-ray-selected clusters within the wide CFHTLS area. Performance of these observations and t…

2015 The Astrophysical Journal
XMM-Newton 20
The Slim-disk State of the Ultraluminous X-Ray Source in M83
DOI: 10.1088/0004-637X/799/2/140 Bibcode: 2015ApJ...799..140S

Soria, Roberto; Blair, William P.; Kuntz, K. D. +3 more

The transient ULX in M83 that went into outburst in, or shortly before, 2010 is still active. Our new XMM-Newton spectra show that it has a curved spectrum typical of the upper end of the high/soft state or slim-disk state. It appears to be spanning the gap between Galactic stellar-mass black holes (BHs) and the ultraluminous state, at X-ray lumin…

2015 The Astrophysical Journal
XMM-Newton 20
Triangulation of the Interstellar Magnetic Field
DOI: 10.1088/2041-8205/813/1/L20 Bibcode: 2015ApJ...813L..20S

McComas, D. J.; Schwadron, N. A.; Richardson, J. D. +2 more

Determining the direction of the local interstellar magnetic field (LISMF) is important for understanding the heliosphere’s global structure, the properties of the interstellar medium, and the propagation of cosmic rays in the local galactic medium. Measurements of interstellar neutral atoms by Ulysses for He and by SOHO/SWAN for H provided some o…

2015 The Astrophysical Journal
SOHO Ulysses 20
Theoretical Clues to the Ultraviolet Diversity of Type Ia Supernovae
DOI: 10.1088/0004-637X/809/1/37 Bibcode: 2015ApJ...809...37B

Baron, E.; Wang, Lifan; Milne, Peter +2 more

The effect of metallicity on the observed light of Type Ia supernovae (SNe Ia) could lead to systematic errors as the absolute magnitudes of local and distant SNe Ia are compared to measure luminosity distances and determine cosmological parameters. The UV light may be especially sensitive to metallicity, though different modeling methods disagree…

2015 The Astrophysical Journal
eHST 19
A Chandra Search for a Pulsar Wind Nebula around PSR B1055-52
DOI: 10.1088/0004-637X/811/2/96 Bibcode: 2015ApJ...811...96P

Pavlov, G. G.; Posselt, B.; Spence, G.

The nearby, middle-aged PSR B1055-52 has many properties in common with the Geminga pulsar. Motivated by the Geminga's enigmatic and prominent pulsar wind nebula (PWN), we searched for extended emission around PSR B1055-52 with Chandra ACIS. For an energy range 0.3-1 keV, we found a 4σ flux enhancement in a 4\buildrel{\prime\prime}\over{.} 9-20

2015 The Astrophysical Journal
XMM-Newton 19