Search Publications
Fragmentation and kinematics of dense molecular cores in the filamentary infrared-dark cloud G011.11-0.12
Henning, Thomas; Beuther, Henrik; Ragan, Sarah E. +2 more
We present new Plateau de Bure Interferometer observations of a region in the filamentary infrared-dark cloud (IRDC) G011.11-0.12 containing young, star-forming cores. In addition to the 3.2 mm continuum emission from cold dust, we map this region in the N2H+(1-0) line to trace the core kinematics with an angular resolution o…
A possible cyclotron resonance scattering feature near 0.7 keV in X1822-371
Sanna, A.; Robba, N. R.; Ferrigno, C. +9 more
Context. The source X1822-371 is a low-mass X-ray binary system (LMXB) viewed at a high inclination angle. It hosts a neutron star with a spin period of ~0.59 s, and recently, the spin period derivative was estimated to be (-2.43 ± 0.05) × 10-12 s/s.
Aims: Our aim is to address the origin of the large residuals below 0.8 keV previo…
X-Ray Emissivity of Old Stellar Populations: A Local Group Census
Jones, Christine; Wang, Q. Daniel; Kraft, Ralph P. +6 more
We study the unresolved X-ray emission in three Local Group dwarf elliptical (dE) galaxies (NGC 147, NGC 185, and NGC 205) using XMM-Newton observations; this emission most likely originates from a collection of weak X-ray sources, mainly cataclysmic variables and coronally active binaries. Precise knowledge of this stellar X-ray emission is cruci…
The composite nature of Dust-Obscured Galaxies (DOGs) at z ∼ 2-3 in the COSMOS field - I. A far-infrared view
Berta, S.; Magnelli, B.; Lutz, D. +19 more
Dust-Obscured Galaxies (DOGs) are bright 24 µm-selected sources with extreme obscuration at optical wavelengths. They are typically characterized by a rising power-law continuum of hot dust (TD ∼ 200-1000 K) in the near-IR indicating that their mid-IR luminosity is dominated by an active galactic nucleus (AGN). DOGs with a fainter…
Evidence for a pressure discontinuity at the position of the Coma relic from Planck Sunyaev-Zel'dovich effect data
Bertoldi, F.; Basu, K.; Klein, U. +2 more
Radio relics are Mpc-scale diffuse synchrotron sources found in galaxy cluster outskirts. They are believed to be associated with large-scale shocks propagating through the intracluster medium, although the connection between radio relics and the cluster merger shocks is not yet proven conclusively. We present a first tentative detection of a pres…
The Star Cluster System in the Local Group Starburst Galaxy IC 10
Lee, Myung Gyoon; Lim, Sungsoon
We present a survey of star clusters in the halo of IC 10, a starburst galaxy in the Local Group, based on Subaru R-band images and NOAO Local Group Survey UBVRI images. We find five new star clusters. All of these star clusters are located far from the center of IC 10, while previously known star clusters are mostly located in the main body. Inte…
Gemini Planet Imager Observations of the AU Microscopii Debris Disk: Asymmetries within One Arcsecond
Matthews, Brenda C.; Duchêne, Gaspard; Esposito, Thomas M. +42 more
We present Gemini Planet Imager (GPI) observations of AU Microscopii, a young M dwarf with an edge-on, dusty debris disk. Integral field spectroscopy and broadband imaging polarimetry were obtained during the commissioning of GPI. In our broadband imaging polarimetry observations, we detect the disk only in total intensity and find asymmetries in …
Ion acceleration dependence on magnetic shear angle in dayside magnetopause reconnection
Fuselier, S. A.; Trattner, K. J.; Petrinec, S. M. +2 more
Magnetic reconnection at the Earth's magnetopause plays an important role in magnetospheric dynamics. Understanding the dynamics requires theory and observations. Previous theoretical work suggests that for no guide field, ions in the exhaust region on the magnetosheath side of the boundary counterstream with a velocity separation that is twice th…
Low CO/CO2 ratios of comet 67P measured at the Abydos landing site by the Ptolemy mass spectrometer
Mousis, O.; Andrews, D.; Morse, A. +4 more
Comets are generally considered to contain the best-preserved material from the beginning of our planetary system, although the mechanism of their formation and subsequent evolution are still poorly understood. Here we report the direct in situ measurement of H2O, CO, and CO2 by the Ptolemy mass spectrometer onboard the Phila…
Cassini INMS measurements of Enceladus plume density
McNutt, R. L.; Waite, J. H.; Teolis, B. D. +5 more
During six encounters between 2008 and 2013, the Cassini Ion and Neutral Mass Spectrometer (INMS) made in situ measurements deep within the Enceladus plumes. Throughout each encounter, those measurements contained density variations that reflected the nature of the source, particularly of the high-velocity jets. Since the dominant constituent of t…