Search Publications
On the widths and ratios of Mg X 609.79 and 624.94 Å lines in polar off-limb regions
Doyle, J. G.; Banerjee, D.; O'Shea, E.
Using measurements of Mg X 609.78 and 624.94 Å lines from the Coronal Diagnostic Spectrometer (CDS) on board SOHO, we seek to examine the variation of line width and line ratio in regions far off-limb at the Northern pole of the Sun. It is found that above ≈1150´´ the ratio of the two coronal Mg X resonance lines reduces to values that might be ex…
ISO's Contribution to the Study of Clusters of Galaxies
Metcalfe, Leo; Fadda, Dario; Biviano, Andrea
Starting with nearby galaxy clusters like Virgo and Coma, and continuing out to the furthest galaxy clusters for which ISO results have yet been published (z = 0.56), we discuss the development of knowledge of the infrared and associated physical properties of galaxy clusters from early IRAS observations, through the “ISO-era” to the present, in o…
Kinematic Structure of H2 and [Fe II] in the Bipolar Planetary Nebula M2-9
Smith, Nathan; Gehrz, Robert D.; Balick, Bruce
We present new high-dispersion, long-slit, infrared (IR) spectra of the double-shell bipolar planetary nebula M2-9 in the emission lines [Fe II] λ16435 and H2v=1-0 S(1) λ21218. H2 spectra reveal for the first time the kinematic structure of the outer shell in M2-9. Kinematics of the inner shell, traced by [Fe II], resemble th…
UV Continuum Spectroscopy of a 6L* z = 5.5 Starburst Galaxy1,
Rosati, P.; Fazio, G. G.; van der Wel, A. +10 more
We have obtained a high S/N (22.3 hr integration) UV continuum VLT FORS2 spectrum of an extremely bright (z850=24.3) z = 5.515 +/- 0.003 star-forming galaxy (BD38) in the field of the z = 1.24 cluster RDCS 1252.9-2927. From HST Advanced Camera for Surveys imaging, this object was selected as a potential z ~ 6 Lyman break galaxy (LBG) ba…
XMM-Newton Spectroscopy of the Starburst-Dominated Ultraluminous Infrared Galaxy NGC 6240
Lutz, D.; Kaspi, Shai; Turner, T. J. +5 more
We present a new XMM-Newton observation of the ultraluminous infrared galaxy (ULIRG) NGC 6240. We analyze the reflecting grating spectrometer (RGS) data, as well as data from the other instruments, and find a starburst-dominated 0.5-3 keV spectrum with global properties resembling those observed in M82 but with a much higher luminosity. We show th…
Time scales of the slowly drifting pulsating structure observed during the April 12, 2001 flare
Bárta, M.; Karlický, M.; Mészárosová, H. +1 more
First time scales of high-frequency (500-1500 MHz) slowly drifting pulsating structures observed during the April 12, 2001 flare by the Ondřejov (800-4500 MHz) and Potsdam (40-800 MHz) radiospectrographs and by the 1420 and 610 MHz Trieste radiopolarimeters (with high time resolution (1 ms)) are studied statistically. The Fourier method reveals pe…
SN 2002kg - the brightening of LBV V37 in NGC 2403
Weis, K.; Bomans, D. J.
SN 2002kg is a type IIn supernova, detected in October 2002 in the nearby spiral galaxy NGC 2403. We show that the position of SN 2002kg agrees within the errors with the position of the LBV V37. Ground based and HST ACS images however show that V37 is still present after the SN 2002kg event. We compiled a lightcurve of V37 which underlines the va…
The Look-back Time Evolution of Far-Ultraviolet Flux from Elliptical Galaxies: The Fornax Cluster and A2670
Rey, Soo-Chang; Heckman, Timothy M.; Madore, Barry F. +30 more
In order to investigate the origin of the far-UV (FUV) flux from the early-type galaxies, the Galaxy Evolution Explorer is collecting the UV data for the elliptical-rich clusters at moderate redshifts (z<0.2) where the dominant FUV source is predicted to be hot horizontal-branch (HB) stars and their post-HB progeny. Here we present our first re…
XMM-Newton observations of the ultra-compact binary RX J1914+24
Cropper, Mark; Wu, Kinwah; Ramsay, Gavin +4 more
We present XMM-Newton observations of the 569-s-period system RX J1914+24 (V407 Vul). This period is believed to represent the binary orbital period making it an ultracompact binary system. By comparing the phase of the rise to maximum X-ray flux at various epochs (this includes observations made using ROSAT, ASCA and Chandra) we find that the sys…
Exploring dark energy with SNAP [review article]
Aldering, G.
The accelerating expansion of the Universe is one of the most surprising and potentially profound discoveries of modern cosmology. Measuring the acceleration well enough to meaningfully constrain interesting physical models requires improvements an order of magnitude beyond on-going and near-term experiments. The Supernova/Acceleration Probe has b…