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High-precision CoRoT space photometry and fundamental parameter determination of the B2.5V star HD 48977
Auvergne, M.; Baudin, F.; Michel, E. +10 more
We present the CoRoT light curve of the bright B2.5V star HD 48977 observed during a short run of the mission in 2008, as well as a high-resolution spectrum gathered with the HERMES spectrograph at the Mercator telescope. We use several time series analysis tools to explore the nature of the variations in the light curve. We performed a detailed a…
Keck-I MOSFIRE Spectroscopy of the z ~ 12 Candidate Galaxy UDFj-39546284
Capak, P.; Scoville, N. Z.; Vieira, J. D. +3 more
We report the results of deep (4.6 hr) H-band spectroscopy of the well studied z ~ 12 H-band dropout galaxy candidate UDFj-39546284 with MOSFIRE on Keck-I. These data reach a sensitivity of 5-10 × 10-19 erg s-1 cm-2 per 4.4 Å resolution element between sky lines. Previous papers have argued that this source could e…
Synoptic Mapping of Chromospheric Magnetic Flux
Pietarila, A.; Harvey, J. W.; Jin, C. L.
We used daily full-disk Ca II 854.2 nm magnetograms from the Synoptic Optical Long Term Investigations of the Sun (SOLIS) facility to study the chromospheric magnetic field from 2006 April through 2009 November. We determined and corrected previously unidentified zero offsets in the SOLIS magnetograms. By tracking the disk passages of stable unipo…
Proton entry into the near-lunar plasma wake for magnetic field aligned flow
Barabash, S.; Futaana, Y.; Wurz, P. +7 more
We report the first observation of protons in the near-lunar (100-200 km from the surface) and deeper (near anti-subsolar point) plasma wake when the interplanetary magnetic field (IMF) and solar wind velocity (vsw) are parallel (aligned flow; angle between IMF and vsw≤10°). More than 98% of the observations during aligned fl…
X-ray observations of the Compton-thick Seyfert 2 galaxy, NGC 5643
Bianchi, S.; Guainazzi, M.; Matt, G. +3 more
We present results from a ~55 ks long XMM-Newton observation of the obscured AGN, NGC 5643, performed in July 2009. A previous, shorter (about 10 ks) XMM-Newton observation in February 2003 had left two major issues open, the nature of the hard X-ray emission (Compton-thin vs. Compton-thick) and of the soft X-ray excess (photoionized vs. collision…
Tully-Fisher analysis of the multiple cluster system Abell 901/902
Gray, M. E.; Wolf, C.; Barden, M. +7 more
Context.
Aims: We derive rotation curves from optical emission lines of 182 disc galaxies (96 in the cluster and 86 in the field) in the region of Abell 901/902 located at z ~ 0.165. We continue the kinematic analysis presented in a previous paper. Here, we focus on the analysis of B-band and stellar-mass Tully-Fisher relations. We examine po…
An X-Ray Study of the Galactic-Scale Starburst-Driven Outflow in NGC 253
Yamasaki, Noriko Y.; Mitsuishi, Ikuyuki; Takei, Yoh
The X-ray properties of hot interstellar gas in a bright, nearby edge-on starburst galaxy, NGC 253, were investigated so as to gain a further understanding of starburst-driven outflow activity by utilizing XMM-Newton and Suzaku. Spectroscopic analyses for three regions of the galaxy characterized by multiwavelength observations, i.e., the superwin…
Serendipitous detection of an overdensity of Herschel-SPIRE 250 µm sources south of MRC 1138-26
Berta, S.; Altieri, B.; Dannerbauer, H. +9 more
We report the serendipitous detection of a significant overdensity of Herschel-Spectral and Photometric Imaging Receiver 250 µm sources in the vicinity of MRC 1138-26. We use an adaptive kernel density estimate to quantify the significance, including a comparison with other fields. The overdensity has a size of ∼3.5-4 arcmin and stands out a…
X-ray absorption variability in NGC 4507
Elvis, Martin; Risaliti, Guido; Nardini, Emanuele +5 more
We present a complete spectral analysis of an XMM-Newton and Chandra campaign of the obscured AGN in NGC 4507, consisting of six observations spanning a period of six months, ranging from 2010 June to December. We detect strong absorption variability on time-scales between 1.5 and 4 months, suggesting that the obscuring material consists of gas cl…
On the Nature of the mHz X-Ray Quasi-periodic Oscillations from Ultraluminous X-Ray Source M82 X-1: Search for Timing-Spectral Correlations
Pasham, Dheeraj R.; Strohmayer, Tod E.
Using all the archival XMM-Newton X-ray (3-10 keV) observations of the ultraluminous X-ray source (ULX) M82 X-1, we searched for a correlation between its variable mHz quasi-periodic oscillation (QPO) frequency and its hardness ratio (5-10 keV/3-5 keV), an indicator of the energy spectral power-law index. When stellar-mass black holes (StMBHs) exh…