Search Publications
Operating modes and cooling capabilities of the 3-stage ADR developed for the Soft-X-ray Spectrometer instrument on Astro-H
Kelley, Richard L.; Porter, Frederick S.; DiPirro, Michael J. +8 more
A 3-stage adiabatic demagnetization refrigerator (ADR) (Shirron et al., 2012) is used on the Soft X-ray Spectrometer instrument (Mitsuda et al., 2010) on Astro-H (Takahashi et al., 2010) [3] to cool a 6 × 6 array of X-ray microcalorimeters to 50 mK. The ADR is supported by a cryogenic system (Fujimoto et al., 2010) consisting of a superfluid heliu…
Geometrical beaming of stellar mass ULXs
Middleton, Matthew J.; King, Andrew
The presence or lack of eclipses in the X-ray light curves of ultraluminous X-ray sources (ULXs) can be directly linked to the accreting system geometry. In the case where the compact object is stellar mass and radiates isotropically, we should expect eclipses by a main-sequence to sub-giant secondary star on the recurrence time-scale of hours to …
Electrostatic and electromagnetic fluctuations detected inside magnetic flux ropes during magnetic reconnection
Wang, Shui; Li, Xing; Huang, Can +6 more
A series of magnetic flux ropes embedded in the ion diffusion region of a magnetotail magnetic reconnection event were investigated in this paper. Waves near the lower hybrid frequency were measured within each of the flux ropes and can be associated with the enhancements of energetic electrons in some of the flux ropes. The waves in the largest f…
Characteristics of quasi-monochromatic ULF waves in the Venusian foreshock
Zhang, Tielong; Mazelle, Christian; Lu, Quanming +5 more
The statistical properties of ULF waves observed upstream of Venus foreshock are investigated. The study is restricted to waves which are observed well below the local proton cyclotron frequency. Using the magnetic field observations from Venus Express between May 2006 and February 2012, 115 quasi-monochromatic ULF wave trains have been identified…
Dark matter implications of the WMAP-Planck Haze
Pierpaoli, Elena; Egorov, A. E.; Gaskins, Jennifer M. +1 more
Gamma rays and microwave observations of the Galactic Center and surrounding areas indicate the presence of anomalous emission, whose origin remains ambiguous. The possibility of dark matter annihilation explaining both signals through prompt emission at gamma rays and secondary emission at microwave frequencies from interactions of high-energy el…
Three-dimensional development of front region of plasma jets generated by magnetic reconnection
Nakamura, R.; Baumjohann, W.; Shinohara, I. +2 more
A three-dimensional fully kinetic particle-in-cell simulation of antiparallel magnetic reconnection is performed to investigate the three-dimensional development of reconnection jet fronts treating three instabilities: the lower hybrid drift instability (LHDI), the ballooning/interchange instability (BICI), and the ion-ion kink instability. Suffic…
Mid- and far-infrared properties of Spitzer Galactic bubbles revealed by the AKARI all-sky surveys
Yamagishi, Mitsuyoshi; Kaneda, Hidehiro; Fukui, Yasuo +9 more
We have carried out a statistical study on the mid- and far-infrared (IR) properties of Galactic IR bubbles observed by Spitzer. Using the Spitzer 8 µm images, we estimated the radii and covering fractions of their shells, and categorized them into closed, broken, and unclassified bubbles with our data analysis method. Then, using the AKARI …
Statistical features of the global polarity reversal of the Venusian induced magnetosphere in response to the polarity change in interplanetary magnetic field
Nilsson, Hans; Zhang, Tielong; Edberg, Niklas J. T. +5 more
In this study we present the first statistical analysis on the effects of heliospheric current sheet crossings on the induced magnetosphere of Venus. These events are of particular interest because they lead to the reconfiguration of the induced magnetosphere with opposite polarity. We use a statistical approach based on 117 orbit pairs, and we st…
A Tale of Two Narrow-line Regions: Ionization, Kinematics, and Spectral Energy Distributions for a Local Pair of Merging Obscured Active Galaxies
Hainline, Kevin N.; Hickox, Ryan C.; Carroll, Christopher M. +4 more
We explore the gas ionization and kinematics, as well as the optical-IR spectral energy distributions for UGC 11185, a nearby pair of merging galaxies hosting obscured active galactic nuclei (AGNs), also known as SDSS J181611.72+423941.6 and J181609.37+423923.0 (J1816NE and J1816SW, z ≈ 0.04). Due to the wide separation between these interacting g…
Observations of an X-shaped Ribbon Flare in the Sun and Its Three-dimensional Magnetic Reconnection
Ding, M. D.; Li, Y.; Qiu, J. +2 more
We report evolution of an atypical X-shaped flare ribbon that provides novel observational evidence of three-dimensional (3D) magnetic reconnection at a separator. The flare occurred on 2014 November 9. High-resolution slit-jaw 1330 Å images from the Interface Region Imaging Spectrograph reveal four chromospheric flare ribbons that converge and fo…