Search Publications
Diffuse Baryons in Cosmic Structures
Cavaliere, Alfonso
I review the processes that govern the amount and the thermal state of the hot plasma pervading clusters and groups of galaxies: the gravitational heating driven by the DM merging histories, the radiative cooling of baryons, and the energy fed back by SNe and by AGNs or quasars. I argue that the X-ray emissions and the entropy levels now observed …
A comparison of the use of genetic and hill-climbing algorithms to fit low-l solar p-mode spectra
Chaplin, W. J.; Elsworth, Y.; Fletcher, S. T.
We present a comparative study of low-l solar p-mode parameters extracted by genetic-algorithm and `standard' hill-climbing minimisation routines. To effect this we make use of observations made in integrated sunlight by the Birmingham Solar-Oscillations Network (BiSON) and the GOLF instrument on board the ESA/NASA SOHO satellite, in addition to a…
High Dispersion Optical Spectroscopy of Planetary Nebulae
Hyung, Siek
HST/FOS Eclipse mapping of IP Pegasi in outburst
Horne, K.; Saito, R. K.; Baptista, R.
IP Pegasi is a deeply eclipsing dwarf nova (Porb= 3.8 hr) which shows 1-2 weeks-long, ≃ 2 mag outbursts every 60-120 days. During outbursts, tidally induced spiral shocks form in its accretion disc as the disc expands and its outer parts feel more effectively the gravitational attraction of the companion star (Steeghs, Harlaftis & H…
Chandra and XMM-Newton Results on the Hubble Constant from Gravitational Lensing
Garmire, G. P.; Dai, X.; Chartas, G.
We report the first detection of time-delayed flares in single X-ray observations of the gravitationally lensed quasar PG 1115+080 performed with the Chandra and XMM observatories. By combining our observed short time-delay between images A1 and A2 of PG 1115+080 of ΔtA1A2 = 0.149 ±0.006 days with recent constraints on the mass fraction…
The XMM-Newton Bright Serendipitous Survey: First Extragalactic Results
Wolter, Anna; Maccacaro, Tommaso; Braito, Valentina +3 more
We present here some initial results from the ongoing XMM-Newton bright serendipitous survey. The survey is aimed at selecting and spectroscopically identifying a large and statistically representative sample of bright (fx ≳ 7× 10‑14 c.g.s) serendipitous X-ray sources in the 0.5–4.5 keV energy band (BSS) and a complementary (…
Hst/stis Observations of Rotation of T Tauri Jets
Ray, T. P.; Eislöffel, J.; Bacciotti, F. +2 more
We report on observations of jets from T Tauri stars with the STIS spectrograph on board of the Hubble Space Telescope (HST). Observations of this kind can resolve structures to within 10--20 AU from the source and thus open the best observational window to the initial generation of jets that is available today. In particular, we can search for in…
Occultations of Stars Brighter Than 15 mag by the Largest Trans-Neptunian Objects in 2004-2014
Denissenko, D. V.
We computed the occultations of stars brighter than 15 mag by the largest trans-Neptunian objects (TNOs) for the next ten years. In our search, we used the following catalogs: Hipparcos; Tycho2 with the coordinates of 2838666 stars taken from UCAC2 (Herald 2003); and UCAC2 (Zacharias et al. 2003) with 16356096 stars between 12.00 mag and 14.99 mag…
Premières observations de Saturne par Cassini
Vandaele, Ann C.
Short-Period Variables in ASAS Photometry
Molenda-Zakowicz, J.
We present results of our study of short--period variables in ASAS photometry. We focus on slowly pulsating B stars (SPBs), most of which were discovered by the Hipparcos satellite. We discuss the problem of aliasing in the ASAS photometry and its influence on the identification of frequencies of SPBs. Finally, we show that the ASAS photometry can…