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Multi-wavelength Observations of the Radio Magnetar PSR J1622-4950 and Discovery of Its Possibly Associated Supernova Remnant
Esposito, Paolo; Rea, Nanda; Drake, Jeremy J. +29 more
We present multi-wavelength observations of the radio magnetar PSR J1622-4950 and its environment. Observations of PSR J1622-4950 with Chandra (in 2007 and 2009) and XMM (in 2011) show that the X-ray flux of PSR J1622-4950 has decreased by a factor of ~50 over 3.7 years, decaying exponentially with a characteristic time of τ = 360 ± 11 days. This …
On the Occurrence of the Third-order Scaling in High Latitude Solar Wind
Bruno, R.; Carbone, V.; Veltri, P. +3 more
The occurrence and nature of a nonlinear energy cascade within the intermediate scales of solar wind Alfvénic turbulence represents an important open issue. Using in situ measurements of fast, high latitude solar wind taken by the Ulysses spacecraft at solar minima, it is possible to show that a nonlinear energy cascade of imbalanced turbulence is…
Complex Gas Kinematics in Compact, Rapidly Assembling Star-forming Galaxies
Amorín, R.; Pérez-Montero, E.; Vílchez, J. M. +3 more
Deep, high-resolution spectroscopic observations have been obtained for six compact, strongly star-forming galaxies at redshift z ~ 0.1-0.3, most of them also known as green peas. Remarkably, these galaxies show complex emission-line profiles in the spectral region including Hα, [N II] λλ6548, 6584, and [S II] λλ6717, 6731, consisting of the super…
Lyα Dominance of the Classical T Tauri Far-ultraviolet Radiation Field
Herczeg, Gregory J.; Brown, Alexander; France, Kevin +6 more
Far-ultraviolet (FUV) radiation plays an important role in determining chemical abundances in protoplanetary disks. H I Lyman α (Lyα) is suspected to be the dominant component of the FUV emission from Classical T Tauri Stars (CTTSs), but is difficult to measure directly due to circumstellar and interstellar H I absorption. To better characterize t…
The Infrared Eye of the Wide-Field Camera 3 on the Hubble Space Telescope Reveals Multiple Main Sequences of Very Low Mass Stars in NGC 2808
Anderson, J.; Milone, A. P.; Marino, A. F. +9 more
We use images taken with the infrared channel of the Wide Field Camera 3 on the Hubble Space Telescope to study the multiple main sequences (MSs) of NGC 2808. Below the turnoff, the red, the middle, and the blue MS, previously detected from visual-band photometry, are visible over an interval of about 3.5 F160W magnitudes. The three MSs merge toge…
Time Delays in Quasi-periodic Pulsations Observed during the X2.2 Solar Flare on 2011 February 15
Schmutz, W.; Zhukov, A. N.; Berghmans, D. +10 more
We report observations of quasi-periodic pulsations (QPPs) during the X2.2 flare of 2011 February 15, observed simultaneously in several wavebands. We focus on fluctuations on timescale 1-30 s and find different time lags between different wavebands. During the impulsive phase, the Reuven Ramaty High Energy Solar Spectroscopic Imager channels in t…
Ground-based Near-infrared Emission Spectroscopy of HD 189733b
Drossart, P.; Waldmann, I. P.; Tinetti, G. +3 more
We investigate the K- and L-band dayside emission of the hot-Jupiter HD 189733b with three nights of secondary eclipse data obtained with the SpeX instrument on the NASA Infrared Telescope Facility. The observations for each of these three nights use equivalent instrument settings and the data from one of the nights have previously been reported b…
The Star Formation History of Leo T from Hubble Space Telescope Imaging
Bell, Eric F.; Dolphin, Andrew E.; Williams, Benjamin F. +9 more
We present the star formation history (SFH) of the faintest known star-forming galaxy, Leo T, based on deep imaging taken with the Hubble Space Telescope (HST) Wide Field Planetary Camera 2 (WFPC2). The HST/WFPC2 color-magnitude diagram (CMD) of Leo T is exquisitely deep, extending ~2 mag below the oldest main-sequence turnoff, permitting excellen…
The First Observations of Low-redshift Damped Lyα Systems with the Cosmic Origins Spectrograph: Chemical Abundances and Affiliated Galaxies
Lehner, N.; Jenkins, E. B.; Prochaska, J. X. +6 more
We present Cosmic Origins Spectrograph (COS) measurements of metal abundances in eight 0.083 < z abs < 0.321 damped Lyα (DLA) and sub-DLA absorption systems serendipitously discovered in the COS-Halos survey. We find that these systems show a large range in metallicities, with -1.10 < [Z/H] < 0.31, similar to the spread foun…
A Spitzer MIPS Study of 2.5-2.0 M ⊙ Stars in Scorpius-Centaurus
Chen, Christine H.; Mamajek, Eric E.; Su, Kate Y. L. +2 more
We have obtained Spitzer Space Telescope Multiband Imaging Photometer for Spitzer (MIPS) 24 µm and 70 µm observations of 215 nearby, Hipparcos B- and A-type common proper-motion single and binary systems in the nearest OB association, Scorpius-Centaurus. Combining our MIPS observations with those of other ScoCen stars in the literature…