Calendar

Jul
13
Wed
XMM-Newton Large Project on SN1006: shocked interstellar medium and asymmetric SN explosion | Fabrizio Bocchino ( INAF- Osservatorio Astronomico di Palermo) @ Aula OAPA
Jul 13 @ 15:30 – 16:30

The remnant of SN1006 is well known to be the archetypical cosmic-ray accelerating supernova remnant, with two bright limbs dominated by non-thermal emission. In the soft X-ray band the emission is dominated by a thermal component which was traditionally associated to the shocked stellar ejecta fragments. In this talk, we will present the results obtained with the XMM-Newton Large Project on this remnant about this component. In particular, we will address the longstanding issue of the lack of apparent X-ray emission from the shocked ISM, which may provide evidence for proton acceleration through the observation of CR back-reaction effects, and a comprehensive study of the X-ray emitting ejecta, which will give us for the first time a direct evidence for an asymmmetric SN Type Ia explosion.

Jul
20
Wed
Overionization: a new paradigm for Mixed-Morphology SNRs | Marco Miceli ( DiFi-UNIPA ) @ Aula OAPA
Jul 20 @ 15:30 – 16:30

Mixed-morphology SNRs are characterized by a shell-like radio emission and a centrally peaked X-ray morphology and are all interacting with molecular clouds. Many models have been proposed to explain these peculiar remnants, but their physical origin is still unclear. The recent discovery of overionized (i. e. recombining) ejecta in 3 MM SNRs has dramatically challenged all the previous models and opened up new, unexpected scenarios. I review the main properties of these remnants and present an XMM-Newton observation of W49B together with a hydrodynamic model developed to explain the new results. I also discuss the (long) list of open questions.

Jul
27
Wed
Role of ejecta clumping and back-reaction of accelerated cosmic rays in the evolution of supernova remnants | Salvatore Orlando ( INAF- Osservatorio Astronomico di Palermo) @ Aula OAPA
Jul 27 @ 15:30 – 16:30

The thermal structure of the post-shock region of a young supernova remnant (SNR) is heavily affected by two main physical effects, namely the back-reaction of accelerated cosmic rays and the Rayleigh-Taylor instabilities developing at the contact discontinuity between the ejecta and the shocked interstellar medium (ISM). In this contribution, we investigate the role played by both physical mechanisms in the evolution of SNRs through detailed MHD modeling.We present a three-dimensional MHD model which describes the expansion of the remnant through a magnetized ISM, including consistently for the first time the initial ejecta clumping and the effects on shock dynamics due to back-reaction of accelerated cosmic rays.

Sep
22
Thu
YouASTRO: A web-based bibliography management system with distributed comments and rating features for astrophysicas ADS papers | Fabrizio Bocchino ( INAF – Osservatorio Astronomico di Palermo) @ Aula OAPA
Sep 22 @ 15:30 – 16:30

We will present a working prototype of YouASTRO (www.youastro.org), a web-based BibTeX-compliant reference management software (RMS) for astrophysical papers in the SAO/NASA ADS database. It also includes as a main feature the concept of distributed paper comments and ratings. Community-based reviews and comments, and more in general participatory information sharing, have proven to be a very effective way to spread the knowledge in many fields, and they are the focus of Web 2.0 applications. In this demo, we will show how to create and manage a BibTeX personal library to use for citations in our own articles and how to share comments on ADS papers. We will briefly discuss what could be the advantages and drawbacks of such a system being widespread adopted by the astrophysical community for its scientific literature.

Sep
29
Thu
Chandra observations of galaxies: AGN-galaxy interactions | Pepi Fabbiano ( Harvard-Smithsonian Center for Astrophysics, Cambridge – USA ) @ Aula OAPA
Sep 29 @ 15:30 – 16:30

This talk will present the results of recent high resolution studies of the nuclear regions of active galaxies with Chandra. With these data we are setting observational constraints on the parameters of AGN feedback, which is considered a main agent in galaxy evolution. I will also report the very recent discovery of a close double supermassive black hole in one of these galaxies.

Oct
27
Thu
An Overview of ATHENA (Advanced Telescope for High ENergy Astrophysics), a Candidate Large Mission for the ESA Cosmic Vision Program | Salvatore Sciortino ( INAF- Osservatorio Astronomico di Palermo) @ Aula OAPA
Oct 27 @ 15:30 – 16:30

As part of the ESA Cosmic Vision program a “Large” mission concept for imaging X-ray Astromomy is currently in phase A study. The mission, nicknamed ATHENA, result from a very fast and aggressive few month long redefinition phase started April 2011 and ending by October 2011 with a selection for possible phase B (definition) study on February 2012. I will briefly discuss the motivation behind and the rationale for this redefinition process, its outcome, the capability of the newly designed Athena space observatory and the major scientific questions this mission will allow to address. I will also briefly present my view on the overall scenario of the ESA science program and the pros e con of the Athena fitting in this evolving scenario and related advancement of European astrophysics.

Jan
24
Thu
Progetti di Ricerca in corso con Gaetano Scandariato | Gaetano Scandariato ( INAF- Osservatorio Astronomico di Palermo) @ Aula OAPA
Jan 24 @ 15:30 – 16:30

MENU`
Antipasto: Anagrafica siciliana alla occidentale
Primo: Risotto di ONC in fotometria NIR
Secondo: Interazione stella-pianeta in salsa magnetica
Contorno: Flambe` di esopianeti
Frutta: Macedonia GAIA affogata in liquore RVS
Dolce: Buffet di possibili collaborazioni:
Studio delle SED delle pre-MS VLMS in Orione Analisi degli spettri RIz di candidati BD in Orione NGC2264 – Campagna osservativa 14-25 Marzo 2008
Chef: Gaetano Scandariato

Feb
14
Thu
Spettroscopi e spettroscopisti all’alba dell’astrofisica | Ileana Chinnici ( INAF – Osservatorio Astronomico di Palermo ) @ Aula OAPA
Feb 14 @ 15:30 – 16:30

Il seminario illustrera` le tematiche della Fellowship recentemente conclusa presso lo Science Museum di Londra; saranno presentati i risultati acquisiti e le prospettive aperte da questi, nonche` la direzione in cui si intende procedere nel prosieguo di questa ricerca.sui primi sviluppi dell’astrofisica, che analizza il contesto di nascita di questa scienza nella seconda meta` dell’Ottocento, evidenziandone alcuni interessanti aspetti.

Feb
28
Thu
Attivita` di divulgazione e didattica all’Osservatorio Astronomico di Palermo: progetti in corso e prospettive future | Laura Daricello ( INAF – Osservatorio Astronomico di Palermo ) @ Aula OAPA
Feb 28 @ 15:30 – 16:30

Una panoramica sulle attivita` di didattica e divulgazione in corso all’OAPa, con approfondimenti sulle risorse economiche, sul personale coinvolto e sui nuovi progetti di finanziamento, portera` ad una discussione sulle iniziative e i progetti per i prossimi anni.

Mar
14
Thu
Il tema scientifico e la missione candidata per l’Astronomia X ad immagine in vista della call ESA per le missioni L2 ed L3 | Salvatore Sciortino ( INAF- Osservatorio Astronomico di Palermo) @ Aula OAPA
Mar 14 @ 15:30 – 16:30

Lo SPC di ESA nella sua riunione del 21 e 22 Febbraio u.s. ha deliberato in merito alle modalita` di selezione delle missioni L2/L3, M3 e M4. Un gruppo di circa 40 ricercatori della comunita’ X europea con rappresentanti degli USA e del Giappone si sono riuniti a Leicester alla fine di Febbraio per discutere sul modo migliore per affrontare la prossima call di ESA. Dopo avere sinteticamente presentato le modalita’ decise dallo SPC di ESA, vi sintetizzero` la discussione avuta a Leicester e il suo esito (positivo a mio avviso) nel muoversi uniti per presentare una idea di missione nel campo dell’Astronomia X ad immagine di cui illustrero` le performance attese e le modalita` organizzative per massimizzare la discussione scientifica intorno alla stessa.