Search Publications
Is Calvera a Gamma-Ray Pulsar?
Halpern, J. P.
Originally selected as a neutron star (NS) candidate in the ROSAT All-Sky Survey, 1RXS J141256.0+792204 ("Calvera") was discovered to be a 59 ms X-ray pulsar in a pair of XMM-Newton observations by Zane et al. Surprisingly, their claimed detection of this pulsar in Fermi γ-ray data requires no period derivative, severely restricting its dipole mag…
Study of the Poynting Flux in Active Region 10930 Using Data-driven Magnetohydrodynamic Simulation
Zhu, X. S.; He, H.; Wang, H. N. +1 more
Powerful solar flares are closely related to the evolution of magnetic field configuration on the photosphere. We choose the Poynting flux as a parameter in the study of magnetic field changes. We use time-dependent multidimensional MHD simulations around a flare occurrence to generate the results, with the temporal variation of the bottom boundar…
AKARI Near-infrared Spectroscopic Observations of Interstellar Ices in the Edge-on Starburst Galaxy NGC 253
Oyabu, Shinki; Onaka, Takashi; Yamagishi, Mitsuyoshi +4 more
We present the spatially resolved near-infrared (2.5-5.0 µm) spectra of the edge-on starburst galaxy NGC 253 obtained with the Infrared Camera on board AKARI. Near the center of the galaxy, we clearly detect the absorption features of interstellar ices (H2O: 3.05 µm, CO2: 4.27 µm, and XCN: 4.62 µm) and…
IRAS 15099-5856: Remarkable Mid-infrared Source with Prominent Crystalline Silicate Emission Embedded in the Supernova Remnant MSH15-52
Kohno, Kotaro; Onaka, Takashi; Yun, Min S. +18 more
We report new mid-infrared (MIR) observations of the remarkable object IRAS 15099-5856 using the space telescopes AKARI and Spitzer, which demonstrate the presence of prominent crystalline silicate emission in this bright source. IRAS 15099-5856 has a complex morphology with a bright central compact source (IRS1) surrounded by knots, spurs, and se…
Searching for Needles in Haystacks—Looking for Gamma-ray Burst γ-rays with the Fermi/LAT Detector
Zheng, W.; Pandey, S. B.; McKay, T. A. +1 more
Since the launch of the Fermi Gamma-ray Space Telescope on 2008 June 11, 55 gamma-ray bursts (GRBs) have been observed at coordinates that fall within 66° of the Fermi Large Area Telescope (LAT) boresight with precise localizations provided by the NASA Swift mission or other satellites. Imposing selection cuts to exclude low Galactic latitudes and…
Longitudinal Drifts of Streamers across the Heliospheric Current Sheet
Morgan, Huw
Potential field source surface (PFSS) extrapolations of the photospheric magnetic field provide a qualitatively correct model of the coronal magnetic structure. We show that the magnetic structure provided by PFSS describes a framework within which high-density coronal streamers are distributed. However, the density structures have considerable fr…
A Search for Lyman Break Galaxies in the Chandra Deep Field South Using Swift Ultraviolet/Optical Telescope
Gronwall, Caryl; Hornschemeier, Ann E.; Basu-Zych, Antara R. +2 more
While the Swift satellite is primarily designed to study gamma-ray bursts, its ultraviolet and optical imaging and spectroscopy capabilities are also being used for a variety of scientific programs. In this study, we use the UV/Optical Telescope (UVOT) instrument on board Swift to discover 0.5 < z < 2 Lyman break galaxies (LBGs). UVOT has co…
INTEGRAL Observations of the γ-Ray Binary 1FGL J1018.6-5856
Rea, Nanda; Torres, Diego F.; Li, Jian +5 more
The Fermi Large Area telescope (Fermi-LAT) collaboration has recently reported that one of their detected sources, namely, 1FGL J1018.6-5856, is a new gamma-ray binary similar to LS 5039. This has prompted efforts to study its multi-frequency behavior. In this report, we present the results from 5.78 Ms International Gamma-Ray Astrophysics Laborat…
Spatially Resolved Star Formation History Along the Disk of M82 Using Multi-band Photometric Data
Mayya, Y. D.; Rosa-González, D.; Rodríguez-Merino, L. H.
We present results on the star formation history and extinction in the disk of M82 over spatial scales of 10'' (~180 pc). Multi-band photometric data covering the far-ultraviolet to the near-infrared bands were fitted to a grid of synthetic spectral energy distributions. We obtained distribution functions of age and extinction for each of the 117 …
Large-scale Shock-ionized and Photoionized Gas in M83: The Impact of Star Formation
Mutchler, Max; McCarthy, Patrick J.; Blair, William P. +20 more
We investigate the ionization structure of the nebular gas in M83 using the line diagnostic diagram, [O III](5007 Å)/Hβ versus [S II](6716 Å+6731 Å)/Hα, with the newly available narrowband images from the Wide Field Camera 3 (WFC3) of the Hubble Space Telescope (HST). We produce the diagnostic diagram on a pixel-by-pixel (0farcs2 × 0farcs2) basis …