Deep MERLIN 5GHz Radio Imaging of Supernova Remnants in the M82 Starburst

The results of an extremely deep, 8-day long observation of the central kpc of the nearby starburst galaxy M82 using MERLIN (Multi-Element Radio Linked Interferometer Network) at 5 GHz are presented. The 17E-06 Jy/beam, rms noise level in the naturally weighted image make it the most sensitive high resolution radio image of M82 made to date. Over 50 discrete sources are detected, the majority of which are supernova remnants, but with 13 identified as HII regions. Sizes, flux densities and radio brightnesses are given for all of the detected sources, which are all well resolved with a majority showing shell or partial shell structures. Those sources within the sample which are supernova remnants have diameters ranging from 0.3 to 6.7 pc, with a mean size of 2.9 pc. From a comparison with previous MERLIN 5 GHz observations made in July 1992, which gives a 9.75 year timeline, it has been possible to measure the expansion velocities of ten of the more compact sources, eight of which have not been measured before. These derived expansion velocities range between 2200 and 10500 km/s.Comment: 34 pages, 10 figures. Accepted by MNRA

Le linee guida ed il loro valore nel contesto medico legale

Negli ultimi decenni, vi è stata una crescente ricerca di interventi efficaci per migliorare la prognosi dello stroke e numerose linee guida sono state prodotte in tal senso. Ciò ha comportato ultimamente, rispetto al passato, un incremento della sopravvivenza del 10% ed un aumento di soggetti che ha superato la malattia senza riportare gravi disabilità permanenti (paralisi, perdita della parola, della visione, della memoria, ecc.) con una percentuale all’incirca identica. E’ da sottolineare che, a differenza di quanto avviene per altre malattie, dove l’attenzione per migliorare la qualità delle cure è rivolta a promuovere l’uso di singoli farmaci o interventi terapeutici, nell’ictus gli sforzi sono stati essenzialmente concentrati sugli aspetti organizzativi e di gestione multidisciplinare dell’assistenza (stroke care), cioè sul management complessivo del paziente relativamente alla gestione clinica della fase acuta, alla prevenzione delle complicanze più frequenti ed alla riabilitazione, sia in fase precoce, sia in fase post-acuta

High-velocity-resolution observations of OH main line lasers in the M82 starburst

Using the VLA, a series of high velocity resolution observations have been made of the M82 starburst at 1.6 GHz. These observations follow up on previous studies of the main line OH maser emission in the central kiloparsec of this starburst region, but with far greater velocity resolution, showing significant velocity structure in some of the maser spots for the first time. A total of thirteen masers were detected, including all but one of the previously known sources. While some of these masers are still unresolved in velocity, these new results clearly show velocity structure in spectra from several of the maser regions. Position-velocity plots show good agreement with the distribution of H{\sc i} including interesting velocity structure on the blueward feature in the west of the starburst which traces the velocity distribution seen in the ionised gas.Comment: MNRAS in press. 15 pages, 9 figure

Monitoring of the prompt radio emission from the unusual supernova 2004dj in NGC2403

Supernova 2004dj in the nearby spiral galaxy NGC2403 was detected optically in July 2004. Peaking at a magnitude of 11.2, this is the brightest supernova detected for several years. Here we present Multi-Element Radio Linked Interferometer Network (MERLIN) observations of this source, made over a four month period, which give a position of R.A. = 07h37m17.044s, Dec =+65deg35'57.84" (J2000.0). We also present a well-sampled 5 GHz light curve covering the period from 5 August to 2 December 2004. With the exception of the unusual and very close SN 1987A, these observations represent the first detailed radio light curve for the prompt emission from a Type II-P supernova.Comment: (1) Jodrell Bank Observatory (2) University of Valencia (3) University of Sheffield 6 pages, 1 figure. To appear in ApJ letter