Search Publications
Hα to FUV ratios in resolved star-forming region populations of nearby spiral galaxies
Kennicutt, Robert C.; Eldridge, John J.; Hermanowicz, Maciej T.
We present a new study of Hα/FUV flux ratios of star-forming regions within a sample of nearby spiral galaxies. We search for evidence of the existence of a cluster-mass-dependent truncation in the underlying stellar initial mass function (IMF). We use an automated approach to identification of extended objects based on the SEXTRACTOR algorithm to…
EMIC waves observed by Cluster near the plasmapause
Liu, Y. H.; Fraser, B. J.; Menk, F. W.
analyze a long-duration electromagnetic ion cyclotron (EMIC) wave event seen in the inner magnetosphere in order to understand the propagation characteristics of these waves in the vicinity of the plasmapause. The study takes advantage of the south to north orbit of the four-satellite Cluster constellation as it passed through perigee at L ~ 4.2 a…
FISS Observations of Vertical Motion of Plasma in Tiny Pores
Cho, K. -S.; Kim, Y. -H.; Chae, J. +3 more
Pores can be exploited for the understanding of the interaction between small-scale vertical magnetic field and the surrounding convective motions as well as the transport of mechanical energy into the chromosphere along the magnetic field. For better understanding of the physics of pores, we investigate tiny pores in a new emerging active region …
The Planck-ATCA Co-eval Observations project: the spectrally selected sample
De Zotti, Gianfranco; Bonaldi, Anna; Massardi, Marcella +1 more
The Planck Australia Telescope Compact Array (Planck-ATCA) Co-eval Observations (PACO) have provided multi-frequency (5-40 GHz) flux density measurements of complete samples of Australia Telescope 20 GHz (AT20G) radio sources at frequencies below and overlapping with Planck frequency bands, almost simultaneously with Planck observations. In this w…
Observations of the magnetars 4U 0142+61 and 1E 2259+586 with the MAGIC telescopes
Maraschi, L.; Covino, S.; Antonelli, L. A. +154 more
Context. Magnetars are an extreme, highly magnetized class of isolated neutron stars whose large X-ray luminosity is believed to be driven by their high magnetic field.
Aims: We study for the first time the possible very high energy γ-ray emission above 100 GeV from magnetars, observing the sources 4U 0142+61 and 1E 2259+586.
Methods: We…
A Good Mass Proxy for Galaxy Clusters with XMM-Newton
Zhao, Hai-Hui; Xie, Fei; Jia, Shu-Mei +3 more
We use a sample of 39 galaxy clusters at redshift z < 0.1 observed by XMM-Newton to investigate the relations between X-ray observables and total mass. Based on central cooling time and central temperature drop, the clusters in this sample are divided into two groups: 25 cool core clusters and 14 non-cool core clusters, respectively. We study t…
A statistical study of post-flare-associated CME events
Youssef, M.; Mawad, R.; shaltout, Mosalam
We present a statistical study of post-flare-associated CMEs (PFA-CMEs) during the period from 1996 to 2010. By investigating all CMEs and X-ray flares, respectively, in the LASCO and GOES archives, we found 15875 CMEs of which masses are well measured and 25112 X-ray flares of which positions are determined from their optical counterparts. Under …
The characteristics of the O2 Herzberg II and Chamberlain bands observed with VIRTIS/Venus Express
Drossart, P.; Piccioni, G.; Soret, L. +6 more
The oxygen Venus nightglow emissions in the visible spectral range have been known since the early observations from the Venera spacecraft. Recent observations with the VIRTIS instrument on board Venus Express allowed us to re-examine the Herzberg II system of O2 and to further study its vertical distribution, in particular the (0-ν″ wi…
Constrained simulations of the Antennae galaxies: comparison with Herschel-PACS observations
Juvela, M.; Klaas, U.; Lunttila, T. +3 more
We present a set of hydro-dynamical numerical simulations of the Antennae galaxies in order to understand the origin of the central overlap starburst. Our dynamical model provides a good match to the observed nuclear and overlap star formation, especially when using a range of rather inefficient stellar feedback efficiencies (0.01 ≲ qEoS
Coronal Mass Ejections Associated with Slow Long Duration Flares
Kołomański, S.; Mrozek, T.; Bąk-Stęślicka, U.
It is well known that there is a temporal relationship between coronal mass ejections (CMEs) and associated flares. The duration of the acceleration phase is related to the duration of the rise phase of a flare. We investigate CMEs associated with slow long duration events (LDEs), i.e. flares with the long rising phase. We determined the relations…