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Can Dust Emission be Used to Estimate the Mass of the Interstellar Medium in Galaxies—A Pilot Project with the Herschel Reference Survey
Gear, Walter; Wilson, Christine D.; De Looze, Ilse +23 more
The standard method for estimating the mass of the interstellar medium (ISM) in a galaxy is to use the 21 cm line to trace the atomic gas and the CO 1-0 line to trace the molecular gas. In this paper, we investigate the alternative technique of using the continuum dust emission to estimate the mass of gas in all phases of the ISM. Using Herschel o…
The Role of Streamers in the Deflection of Coronal Mass Ejections: Comparison between STEREO Three-dimensional Reconstructions and Numerical Simulations
Mierla, M.; Poedts, S.; Bemporad, A. +3 more
On 2009 September 21, a filament eruption and the associated coronal mass ejection (CME) were observed by the Solar Terrestrial Relations Observatory (STEREO) spacecraft. The CME originated from the southern hemisphere and showed a deflection of about 15° toward the heliospheric current sheet (HCS) during the propagation in the COR1 field of view.…
Separation of Two Contributions to the High Energy Emission of Cygnus X-1: Polarization Measurements with INTEGRAL SPI
Clark, D. J.; Jourdain, E.; Roques, J. P. +1 more
Operational since 2002 on board the INTEGRAL observatory, the SPI spectrometer can be used to perform polarization measurements in the hard X-ray/softγ-ray domain (~130 keV-8 MeV). However, this phenomenon is complex to measure at high energy and requires high fluxes. Cyg X-1 appears to be the best candidate amongst the X-ray binaries since it is …
New Insight into Short-wavelength Solar Wind Fluctuations from Vlasov Theory
Belmont, G.; Sahraoui, F.; Goldstein, M. L.
The nature of solar wind (SW) turbulence below the proton gyroscale is a topic that is being investigated extensively nowadays, both theoretically and observationally. Although recent observations gave evidence of the dominance of kinetic Alfvén waves (KAWs) at sub-ion scales with ω < ωci, other studies suggest that the KAW mode cann…
Calibrating 100 Years of Polar Faculae Measurements: Implications for the Evolution of the Heliospheric Magnetic Field
DeLuca, Edward E.; Zhang, Jie; Muñoz-Jaramillo, Andrés +1 more
Although the Sun's polar magnetic fields are thought to provide important clues for understanding the 11 year sunspot cycle, including the observed variations of its amplitude and period, the current database of high-quality polar field measurements spans relatively few sunspot cycles. In this paper, we address this deficiency by consolidating Mou…
XMM-Newton Detects a Hot Gaseous Halo in the Fastest Rotating Spiral Galaxy UGC 12591
Bregman, Joel N.; Anderson, Michael E.; Miller, Jon M. +1 more
We present our XMM-Newton observation of the fastest rotating spiral galaxy UGC 12591. We detect hot gas halo emission out to 80 kpc from the galaxy center, and constrain the halo gas mass to be smaller than 4.5 × 1011 M ⊙. We also measure the temperature of the hot gas as T = 0.64 ± 0.03 keV. Combining our x-ray constraints …
The Star Formation in Radio Survey: GBT 33 GHz Observations of Nearby Galaxy Nuclei and Extranuclear Star-forming Regions
Helou, G.; Murphy, E. J.; Armus, L. +7 more
We present 33 GHz photometry of 103 galaxy nuclei and extranuclear star-forming complexes taken with the Green Bank Telescope as part of the Star Formation in Radio Survey. Among the sources without evidence for an active galactic nucleus, and also having lower frequency radio data, we find a median thermal fraction at 33 GHz of ≈76% with a disper…
The Evolution of Lyα-emitting Galaxies between z = 2.1 and z = 3.1
Gronwall, Caryl; Gawiser, Eric; Ciardullo, Robin +11 more
We describe the results of a new, wide-field survey for z = 3.1 Lyα emitters (LAEs) in the Extended Chandra Deep Field South (ECDF-S). By using a nearly top-hat 5010 Å filter and complementary broadband photometry from the MUSYC survey, we identify a complete sample of 141 objects with monochromatic fluxes brighter than 2.4 × 10-17 erg …
Coronal Magnetic Field Measurement from EUV Images Made by the Solar Dynamics Observatory
Gopalswamy, Nat; Akiyama, Sachiko; Yashiro, Seiji +2 more
By measuring the geometrical properties of the coronal mass ejection (CME) flux rope and the leading shock observed on 2010 June 13 by the Solar Dynamics Observatory (SDO) mission's Atmospheric Imaging Assembly we determine the Alfvén speed and the magnetic field strength in the inner corona at a heliocentric distance of ~1.4 Rs. The basic measure…
Major-merger Galaxy Pairs in the COSMOS Field—Mass-dependent Merger Rate Evolution since z = 1
Capak, P.; Scoville, N.; Gao, Y. +3 more
We present results of a statistical study of the cosmic evolution of the mass-dependent major-merger rate since z = 1. A stellar mass limited sample of close major-merger pairs (the CPAIR sample) was selected from the archive of the COSMOS survey. Pair fractions at different redshifts derived using the CPAIR sample and a local K-band-selected pair…