Seminar Programme

Date: 26 February (Fri)

Time: 15:00

Place: 6th floor meeting room, Mayantigo building

Title: Variability and stability in optical blazar jets: photopolarimetric monitoring of OJ287 in 2005-2009

Speaker (Affiliation): Carolin Villforth (Space Telescope Science Institute, USA)

Abstract: Blazars are a subclass of AGN with jets pointing almost directly towards the observer, making them perfect object for studying the properties of AGN jets. We present photopolarimetric monitoring of the blazar OJ287 and discuss implications for jet physics. Additionally, this particular object is of special interest as it has shown regularly appearing double-peaked bursts and is therefore suspected to host a supermassive binary black hole. Our data can also be used to assess different binary black hole models.

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Date: 12 February (Fri)

Time: 15:00

Place: 6th floor meeting room, Mayantigo building

Title: SHARDS: Understanding the mass assembly of galaxies at 0

Speaker (Affiliation): Pablo G. Pérez-González (Universidad Complutense de Madrid)

Abstract: We will present the main results of our research about the assembly of galaxies at z<4 based on observations obtained by the deepest surveys, noticeably including mid- and far-IR data taken with Spitzer. Analyzing SFR and stellar mass functions in several redshift bins at 0

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Date: 9 February (Tue)

Time: 11:00

Place: 6th floor meeting room, Mayantigo building

Title: The faint extragalactic radio source population

Speaker (Affiliation): Chris Simpson (Liverpool John Moores University)

Abstract: With LOFAR and e-MERLIN about to start taking data, and SKA on the horizon, I will describe what we know about the composition of the extragalactic radio source population and, in particular, the advances that have been made in understanding the microJansky sources. I will then look to the future to discuss what progress is likely to be made in addressing the existing uncertainties in our current picture.

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Date: 5 February (Fri)

Time: 11:00

Place: 6th floor meeting room, Mayantigo building

Title: The making of planetary embryos

Speaker (Affiliation): Cornelis Dullemond (Max Planck Institute for Astronomy, Heidelberg)

Abstract: Making planets out of dust is one of Nature's tricks that we still haven't understood well. This is remarkable, because modern science has struggled with this question for many decades. Recent developments in observations of protoplanetary disks and exoplanetary systems, new developments in numerical models of the planet formation process, as well as over a decade of laboratory experiments of colliding dusty bodies, have shed new light on this issue. But this new information is cryptical: it is not obvious how to derive an answer to the above question from it. I will talk about various theoretical modeling efforts that try to synthesize these various crytic pieces of the puzzle to obtain a full picture, though I will focus my talk on the growth process from dust to "planetary embryos", i.e. thousand-kilometer size planetary building blocks. I will show that while some answers are found, new questions are raised. Most importantly, I will show how current and future observations of various kinds (can) put constraints on these models.

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Date: 15 January (Fri)

Time: 11:00

Place: 6th floor meeting room, Mayantigo building

Title: Developing global observatory network - the software environment of the Bootes observatories and other

Speaker (Affiliation): Petr Kubanek (Image Processing Laboratory, Universitat de Valencia, and IAA, Spain)

Abstract: I will present an open source system we are developing for control of various, usually fully autonomous, observatories. The system is capable taking care of the weather, selecting targets for observations, and doing basic image image processing. The system is called RTS2 and is being developed for almost a decade, and controlling more then 10 observatories. It primary task was a quick follow ups observations of Gamma Ray Bursts fields, but it is now making progress towards a generic observatory control environment. It design philosophy, lessons learned during development, as well as some of the results obtained will be presented.

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Title: Abell 41: Nebular Shaping by a Binary Central Star?

Speaker (Affiliation): David Jones (Jodrell Bank Centre for Astrophysics, Univ. of Manchester, UK)

Abstract: Although the theoretical link between bipolar planetary nebulae and binary central stars is long established, there is little observational support for this hypothesis. Here, I will discuss some of the observational tests being employed to evaluate the validity of the hypothesis, before focussing on one particular 'test-case' object. Abell 41, one of a small percentage of planetary nebulae known to contain a central binary system, in this case the well-studied, close-binary MT Serpentis. As such, Abell 41 represents an ideal object to test the so-called 'Binary Hypothesis'. I present detailed spatio-kinematic modelling, based on deep narrow-band WHT-ACAM imagery along with high resolution MES-SPM longslit spectroscopy, in order to determine the relationship between the plane of the central binary and any nebular symmetry axis. Thus, testing one of the fundamental predictions of all theories of binary-induced nebular shaping, that the nebular symmetry axis will be perpendicular to the plane of the central binary.

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Date: 14 December (Mon)

Time: 17:00

Place: 6th floor meeting room, Mayantigo building

Title: RaTS and the search for Ultra-Compact binaries

Speaker (Affiliation): Gavin Ramsay (Armagh Observatory, UK)

Abstract: Ultra Compact Binaries are predicted to be the strongest known sources of gravitational waves in the LISA pass-band. Since they are at the short period end of the orbital period distribution (<70 mins), their number is a sensitive test of binary evolutionary models. The best method to detect these short period systems, whose optical light is dominated by an accretion disk and show optical intensity variations on timescales close to their orbital period, is through deep, wide-field, fast-cadence photometric surveys. The RaTS (Rapid Temporal Survey) project is unique in that it is sensitive to variability on timescales as short as 2 mins and systems with V~22. Our strategy and initial results will be presented.

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Date: 30 November (Mon)

Time: 15:00

Place: 6th floor meeting room, Mayantigo building

Title: Observational studies of gas in protoplanetary disks

Speaker (Affiliation): Andres Carmona Gonzalez (Astronomical Observatory, University of Geneva)

Abstract: Circumstellar disks are essential in the process of star and planet formation. Early in the star's life they permit the inflow of material from the primordial cloud to the star and the outward transport of angular momentum. During the pre-main sequence, also known as the T Tauri phase, these reservoirs of dust and gas are the sites of planet formation. Although protoplanetary disks are composed of 99% gas and only 1% dust, our physical understanding of these disks has been based mostly on the study of dust emission. The dust dominates the opacity, therefore, it is much easier to observe. However, as the gas is the dominant mass component, to derive observational constraints of gas properties in the disk is fundamental for our understanding of disk physics, therefore, planet formation. Several fundamental questions about planet formation remain unanswered: How much material is available for forming planets? How long is the disk life-time? How does the disk dissipate? What are the dynamics of disks? The answers to these questions will require direct observational constraints of the gas, especially from the region where planets are expected to form (R<10AU). The advent of high-resolution spectrographs in the IR opened the way to the observational study of the gas in the inner disk. In this talk I will review I discuss several observational diagnostics in the UV, optical, near-IR, mid-IR, and (sub)-mm wavelengths that have been employed to study the gas in the disks of young stellar objects. I will concentrate in diagnostics that probe the inner 20 AU of the disk, the region where planets are expected to form. I will discuss the potential and limitations of each gas tracer, what we have learned and present prospects for future research. In addition, I will discuss briefly our current project with NOTCAM: NIR spectroscopy of candidates to young stellar objects in Taurus. Reference: Carmona, A. 2009 http://arxiv.org/abs/0911.2271

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Date: 24 November (Tue)

Time: 15:00

Place: 6th floor meeting room, Mayantigo building

Title: Optical and NIR studies of short period low mass X-ray binaries (LMXB)

Speaker (Affiliation): Pasi Hakala (Tuorla Observatory, University of Turku, Finland)

Abstract: I present some recent results from our Optical and NIR studies of five short period LMXB's (X1822-371, X1957+115, UW CrB, X1916-05 and X0614+091). Optical photometry and spectroscopy reveal some surprising results on the geometry and evolution of accretions discs in LMXB's. Based on our data, it is increasing clear that accretion discs in these systems are far from being stable and must undergo substantial precession and/or warping behaviour on timescales less than a day in case of the shortest period systems.

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Date: 20 November (Tue)

Time: 15:00

Place: 6th floor meeting room, Mayantigo building

Title: Star-forming Galaxies in the Hercules Cluster: Spectroscopic Properties

Speaker (Affiliation): Vasiliki Petropoulou (IAA)

Abstract: I will present preliminary results of the spectroscopic follow-up of a sample of star forming galaxies in the Hercules cluster, performed with INT/IDS and WHT/ISIS. The sample was defined by the Halpha imaging survey in the central region of the A2151 cluster, performed by our group (Cedres et al. 2009). The central goal of this project is to study the impact of the cluster environment on the evolution of these galaxies and search for observable imprints on their photo-chemical evolution.

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Date: 23 October (Wed)

Time: 15:00

Place: 6th floor meeting room, Mayantigo building

Title: A new review of accurate stellar masses and radii

Speaker (Affiliation): Johannes Andersen (NOT)

Abstract: A new review of accurate stellar masses and radii has been performed. We find 95 detached binary systems in which the components have basically evolved as single stars and have mass and radius determinations to 3% accuracy or better. 21 systems have spectroscopic metallicities as well. Effective temperatures, reddening, rotational velocities and approximate ages are also provided when possible. We discuss the use of the data to test models of stellar structure and evolution, the properties of mildly active stars, and the tidal evolution of the stars and their orbits, including the implications for general relativity.

Slides: PPT | PDF

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Date: 21 October (Wed)

Time: 11:00am

Place: Fundación Galileo Galilei; Rambla José Ana Fernández Pérez, 7; Breña Baja

Title: Analysis of asteroid Steins resolved surface from Rosetta spacecraft

Speaker (Affiliation): Sara Magrin (Dipartimento di Astronomia, Padua University)

Abstract: On September 5th 2008 the Rosetta spacecraft had a fly-by with the main belt asteroid Steins, at a distance of about 800 Km from the body. OSIRIS WAC and NAC (Wide Angle and Narrow Angle Cameras) observed the 5 Km sized object at different phase angles with different filters. To analyze the possible color variegation of the surface of Steins we developed an IDL tool to produce pixel per pixel (rough) spectra, by using values of albedo in three different filters at a time. The results of this analysis performed on the data obtained by the NAC camera will be shown.

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Date: 13 October (Tue)

Time: 16:30

Place: 6th floor meeting room, Mayantigo building

Title: Overview of the European Extremely Large Telescope

Speaker (Affiliation): Isobel Hook (Dept. of Astrophysics, Univ. of Oxford)

Abstract: The European ELT is now in the detailed design phase, leading to a proposal for construction that will be presented to ESO Council in late 2010. If approved, the ELT will see first light in around 2018. In this talk I will present a summary of the science case, which ranges from studies of exo-planets to the most distant galaxies and cosmology. I will show some recent results from science simulations developed as part of the Design Reference Mission. I will also give an overview of the telescope and the ELT instrument studies that are currently underway.

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Presentation: On DVD, please contact Javier Méndez.

Date: 9 October (Fri)

Time: 15:00

Place: 6th floor meeting room, Mayantigo building

Title: The 6.5 m MMT's f/5 instruments - with a focus on high-resolution multi- and single-object spectroscopy

Speaker (Affiliation): Gabor Furesz (Smithsonian Astrophysical Observatory Cambridge, MA, USA)

Abstract: In this talk I briefly review the f/5 wide field optics and instruments built by SAO for the 6.5m MMT telescope: the 1.7m diameter f/5 secondary, the f/5 corrector lens and ADC prism, wavefront sensor, the 1/2 deg imager Megacam, the multi-slit NIR imaging spectrograph MMIRS, the NIR camera SWIRC, the low and high res multi-object spectrographs Hectospec and Hectochelle, and Binospec, the dual-beam high throughput VIS multi-slit imaging spectrograph. I'll discuss some of the technical details in optical mounting and design, which were the results of SAO's internal R&D work, and potentially can be very benefitial for future instrument developments by other groups. During the second part of the talk the focus will be on high resolution spectroscopy. I'll discuss the Hectochelle instrument in more detail, the pros and cons of this multi-object echelle in comparison of other similar instruments, and in the light of measuring precision radial velocities (PRV). After showing some of the scientific results of Hectochelle on cluster dinamics we will shift to PRV measurements on single stars, as the key tool for exoplanet research. In this 3d part I'll summarize SAO's instrumental and scientific experience on some of the important instrumental and scientific aspects of PRV work, based on our involvment in the HAT-Net, Kepler, HARPS-Nef and GMT projects.

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Presentation: On DVD, please contact Javier Méndez.

Date: 23 September (Wed)

Time: 11:00am

Place: Fundación Galileo Galilei; Rambla José Ana Fernández Pérez, 7; Breña Baja

Title: Deep LBT photometry of VV124: an isolated dwarf galaxy falling into the Local Group

Speaker (Affiliation): Michele Bellazzini (INAF - Osservatorio Astronomico di Bologna)

Abstract: VV124 == UGC4879 has been recently recognized as a dwarf galaxy lying in the outskirts of the Local Group (Kopylov et al. 2008). I present the preliminary results from our very deep LBT observations of this galaxy. We derived a Color-Magnitude diagram reaching r=26.5, down to ~4 mag below the RGB Tip and more than two magnitude deeper than previously available photometries. We obtain a very clean detection of the RGB tip, deriving a distance of 1.3 Mpc. Our CMD reveals that the galaxy is dominated by an old and metal-poor population, and it displays a metallicity gradient; a tentative detection of and extended HB and RR Ly population is also obtained. Coupling surface photometry and star-counts we are able to trace the Surface Brightness profile of the galaxy out to ~5' (=2 kpc), that is 5 times more extended than previous studies. We provide some interesting evidences suggesting that VV124 is a good representative of the pristine status of dwarf Spheroidal galaxies, before that close interactions with the main galaxy they are orbiting around transformed them into the very Low SB system we observe today.

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Date: 21 August (Fri)

Time: 12:00am

Place: Fundación Galileo Galilei; Rambla José Ana Fernández Pérez, 7; Breña Baja

Title: CTA: toward the next generation of Cherenkov Telescopes

Speaker (Affiliation): Angelo Antonelli (INAF - Osservatorio Astronomico di Roma)

Abstract: Very-high-energy gamma-ray astronomy has witnessed a major breakthrough with the physics results obtained by ground-based instruments during the last few years. These results have demonstrated impressively the huge potential of this field, not only in the area of astrophysics, but also in particle physics and cosmology. However, it also became apparent that the performance of current instruments is not sufficient to tap the full physics potential. The answer of the European VHE energy community to that challenge is the Cherenkov Telescope Array (CTA). In this talk I will shortly review the CTA project.

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Date: 8 July (Wed)

Time: 12:00

Place: Fundación Galileo Galilei; Rambla José Ana Fernández Pérez, 7; Breña Baja

Title: An overview to the interacting binary class of Symbiotic Stars and the ongoing 2008-09 outburst of the system CI Cyg

Speaker (Affiliation): Bryce Croll, PhD Student (University of Toronto, Canada)

Abstract: We present an overview to the interacting binary systems knows as the name of Symbiotic Stars, in which a hot compact object (very often a White Dwarf) accretes material from a late type giant via stallar wing or Roche overflow. In particular we discuss about the early phases of the ongoing outburst that CI Cyg, a prototype of this class, is currently undergoing after thirty years of flat quiescence. The outburst started while the accreting WD was being eclipsed by the Roche-lobe filling M giant companion, and it was discovered during the egress phase on the second half of August 2008. The outburst reached peak V-band brightness in early October 2008 and has been characterized by amplitudes up to 1.9, in B band. At maximum V-band brightness, the outbursting WD had expanded to closely resemble an F3 II/Ib star, with M_V=-3.5, T_{eff} ~ 6900 K and R=28 R_{sun}. The high ionization emission lines ([NeV], [FeVII], HeII), so prominent in quiescence, disappeared, and only lower ionization lines (Balmer, HeI, SiII, FeII, [OI]) were visible. During the outburst, Balmer and HeI emission lines declined in equivalent width but increased in absolute flux. The output radiated by the hot component during the outburst corresponds to nuclear burning proceeding at a 2.10e{-8} M_{sun}/yr rate.

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Date: 11 June (Thu)

Time: 15:00

Place: 6th floor meeting room, Mayantigo building

Title: Exploring the Diversity of Planets in other Solar Systems

Speaker (Affiliation): Bryce Croll, PhD Student (University of Toronto, Canada)

Abstract: I will discuss preliminary results from three ongoing observational projects that will form my thesis on extrasolar planets. I will present preliminary results from very recent CFHT WIRCam observations of the secondary eclipses of two of the hottest of the hot Jupiters in the near-infrared. We hope to detect the secondary eclipses of a number of hot Jupiters in the J, H and K near-infrared bands. I will touch upon progress from my ongoing project using GMOS on Gemini-South & North to search for atmospheric absorption from various chemicals in the transmission spectra of hot Jupiters. Lastly, I will discuss the preliminary results from our Spitzer IRAC 8.0 micron observations of the thermal phase curve of the eccentric (e~0.67) hot Jupiter HD 17156. Our observations are the first to probe more than one pseudo-spin period of an eccentric exoplanet. The goal of these observations is to detect the variation in thermal emission of the planet as a single face of the planet is flash-heated as it makes its "Big Swing" into periastron and then this flash heated face rotates in and out of view as the planet cools as it swings out towards apastron.

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Date: 11 June (Thu)

Time: 15:00

Place: 6th floor meeting room, Mayantigo building

Title: Exploring the Diversity of Planets in other Solar Systems

Speaker (Affiliation): Bryce Croll, PhD Student (University of Toronto, Canada)

Abstract: I will discuss preliminary results from three ongoing observational projects that will form my thesis on extrasolar planets. I will present preliminary results from very recent CFHT WIRCam observations of the secondary eclipses of two of the hottest of the hot Jupiters in the near-infrared. We hope to detect the secondary eclipses of a number of hot Jupiters in the J, H and K near-infrared bands. I will touch upon progress from my ongoing project using GMOS on Gemini-South & North to search for atmospheric absorption from various chemicals in the transmission spectra of hot Jupiters. Lastly, I will discuss the preliminary results from our Spitzer IRAC 8.0 micron observations of the thermal phase curve of the eccentric (e~0.67) hot Jupiter HD 17156. Our observations are the first to probe more than one pseudo-spin period of an eccentric exoplanet. The goal of these observations is to detect the variation in thermal emission of the planet as a single face of the planet is flash-heated as it makes its "Big Swing" into periastron and then this flash heated face rotates in and out of view as the planet cools as it swings out towards apastron.

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Date: 26 May (Tue)

Time: 12:00

Place: Fundación Galileo Galilei; Rambla José Ana Fernández Pérez, 7; Breña Baja

Title: Nine years of Solar System research using TNG

Speaker (Affiliation): Javier Licandro (IAC)

Abstract: In this talk I will present the major results of my research on surface properties of trans-neptunian objects and related minor bodies using TNG started in 2000. Results include the characterization of large TNOs like Eris, Makemake and, in particular, Haumea and the family of objects related with it; the determination of the surface characteristics of asteroids in cometary orbits; the mineralogy of Near Earth Asteroids and the relation with meteorites and main belt asteroids.

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Date: 19 May (Tue)

Time: 12:00

Place: Fundación Galileo Galilei; Rambla José Ana Fernández Pérez, 7; Breña Baja

Title:

Speaker (Affiliation):

Abstract: Several astrophysical and cosmological tests demand a more accurate knowledge of the morphological distribution of clusters of galaxies. I will show how multi-wavelength observations allow to obtain information on the intrinsic three-dimensional shape of galaxy structures, and present results of our ongoing work on the subject and future applications.

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Title: Post Common Envelope Binaries from the Sloan Digital Sky Survey

Speaker (Affiliation): Stelios Pyrzas, (ING & University of Warwick)

Abstract: While the majority of (wide) binaries evolve as if they were single stars, a fraction of them is expected to undergo a common envelope phase (CEp), giving birth to close binaries. The classes of objects affected by the CEp include supernova Ia progenitors, low mass X-ray binaries, ultracompact binaries and progenitors of short gamma ray bursts. Thus, Post Common Envelope Binaries (PCEBs), i.e. binaries that have undergone a CE phase during their evolution, play a key role in our understanding of close binary systems. Despite the clear importance, the current theoretical understanding of the CE phase is rather poor and underconstrained by observations. In this talk, I will present an ongoing project, aiming to build a large, well-defined sample of PCEBs, identified in the Sloan Digital Sky Survey (SDSS), with observationally determined stellar parameters. I will refer to the current status of the project, focus on the methods and techniques used and present important first results.

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Date: 13 April (Mon)

Time: 15:00

Place: 6th floor meeting room, Mayantigo building

Title: CSI: PN (CircumStellar Investigation: Planetary Nebula) - SuWt 2 and its mysterious central stars

Speaker (Affiliation): David Jones (ING & Jodrell Bank Centre for Astrophysics)

Abstract: It is generally believed that binary systems play a major role in the shaping of planetary nebulae (PNe), although to date there is little observational evidence linking PN morphologies to the parameters of their central star systems. In the case of SuWt 2, the star observed at its centre is a double A-type eclipsing binary with a period of 4.9 days, and as such contains no star considered old enough to have been the nebular progenitor. This represents a major challenge not only to current theories linking PN and binary star evolution, but also to standard theories of intermediate-mass stellar evolution. In April 2005, as part of a continuing programme to study the morphology and kinematics of PNe with known close-binary central stars, spatially- resolved high-resolution longslit profiles of SuWt 2 were acquired using EMMI on the ESO-NTT. Here, I present the analysis of these position-velocity (PV) arrays, and the subsequent spatio-kinematic modelling performed in an attempt to replicate these results in synthetic spectra, hence determining the nebular morphology of SuWt 2. I will also discuss my findings in relation to the A-type binary and, most importantly, the various evolutionary scenarios that have been put forward for SuWt 2.

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Date: 1 April (Wed)

Time: 11:00am

Place: 6th floor meeting room, Mayantigo building

Title: LUCIFER - the LBT NIR spectroscopic Utility with Camera and Integral-Field Unit for Extragalactic Research

Speaker (Affiliation): Jochen Heidt (ZAH, Landessternwarte Heidelberg, Germany)

Abstract: LUCIFER is a NIR spectrograph and imager (wavelength range 0.9 to 2.5 micron) for the Large Binocular Telescope (LBT) on Mt. Graham, Arizona, working at cryogenic temperatures of less than 70K. Two instruments are built by a consortium of five German institutes and will be mounted at the bent Gregorian foci of the two individual telescope mirrors. Three exchangable cameras are available for imaging and spectroscopy: two of them are optimized for seeing-limited conditions, a third camera for the diffraction limited case will be used with the LBT adaptive secondary mirror working. Up to 33 exchangeable masks are available for longslit or multi-object spectroscopy (MOS) over the full field of view. At present, the commissioning of the first LUCIFER instrument at the LBT is almost complete. In this talk, I will give an overview about the LBT organisation and the operation of the LBT followed by an description of the instrument and the first results obtained during commissioning.

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Date: 20 March (Friday)

Time: 10:00am

Place: 6th floor meeting room, Mayantigo building

Title: Young stars in Lupus: not as expected, not where expected

Speaker (Affiliation): Fernando Comeron (ESO)

Abstract: Most studies of the stellar and substellar populations of star forming regions rely on the identification of the signatures of accretion, outflows, circumstellar dust or activity characteristic of the early stages of stellar evolution. However, the decay of these observational signatures with time limits our ability to understand the complete star forming history of young aggregates, and to obtain unbiased samples of young stellar objects at different stages of disk evolution. I will present the results of a wide-area study of the stellar population of selected clouds in the nearby Lupus star forming region, initially defined to complement the data obtained by the Spitzer Space Observatory Legacy Program "From molecular cores to planet-forming disks". When combined with 2MASS photometry, our data allow us to fit the spectral energy distributions of well over 150,000 sources seen in that direction, and to identify possible new members based on their photospheric fluxes alone, with independence of the display of signposts of youth. In this way we identify a very clear signature of the existence of a surprisingly numerous and thus far unrecognized population of cool members of Lupus 1 and 3, which is absent from Lupus 4. The approximately 130 new members that we identify show that Lupus 1 and 3 have been forming low mass stars in numbers comparable to, or even exceeding in Lupus 1, those revealed by recent sensitive surveys based on the signposts of youth. We hypothesize on several possibilities for the origin of this population that may account for its puzzling properties of general lack of disks, coevality with the disk-bearing population, and preferential off-cloud location, which hint at a picture more complex and interesting than the quiescent formation inside dense molecular clouds.

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Presentation: PPT | PDF

Date: 9 March (Monday)

Time: 16:00

Place: 6th floor meeting room, Mayantigo building

Title: A rate study of Type Ia supernovae with Subaru/XMM-Newton Deep Survey

Speaker (Affiliation): Yutaka Ihara (Institute of Astronomy, University of Tokyo, Japan)

Abstract: I will talk about my study, a measurement of the rate of high-z Type Ia supernovae (SNe Ia) using multi-epoch observations of Subaru/XMM-Newton Deep Field (SXDF) with Suprime-Cam on the Subaru Telescope. Although SNe Ia are regarded as a standard candle, progenitor systems of SNe Ia have not been resolved yet. One of the key parameters to show the progenitor systems by observations is the delay time distribution between the binary system formation and subsequent SN explosion. Recently, a wide range of delay time is studied by SN Ia rates compared with an assumed cosmic star formation history. If SNe Ia with short delay time are dominant, the cosmic SN Ia rate evolution should closely trace that of the cosmic star formation. In order to detect a lot of high-z SNe Ia, we repeatedly carried out wide and deep imaging observations in the i-band with Suprime-Cam in 2002 (FoV~1 deg^2, m_i<25.5 mag). We obtained detailed light curves of the variable objects, and 50 objects are classified as SNe Ia using the light curve fitting method at the redshift range of 0.2

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Presentation: PPT

Date: 17 Feb (Tuesday)

Time: 12:00

Place: Fundación Galileo Galilei; Rambla José Ana Fernández Pérez, 7; Breña Baja

Title: Globular Clusters - Some simple, some complicated, all interesting!

Speaker (Affiliation): Alistair Walker, (Cerro Tololo Inter-American Observatory, National Optical Astronomy Observatory)

Abstract: Galactic globular clusters have for several decades been highly useful as examples of single stellar populations of stars almost as old as the Universe, and as such have been critical to calibrating models of stellar evolution for low mass stars, and for understanding galaxy formation and evolution. However, explanations for puzzles such as differing distributions of stars on the Horizontal Branch, and element-element abundance anomalies in individual clusters, have been elusive. Recent, mostly HST-ACS, observations of some globular clusters have complicated the picture but also give strong clues for resolving the remaining issues. After a short overview, I will describe a wide-field imaging program for a selected sample of clusters designed to provide complementary information to the HST and spectroscopic studies, and show some of the first results.

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Date: 13 Feb (Friday)

Time: 15:00

Place: 6th floor meeting room, Mayantigo building

Title: Status and Plans for the ASTRONET Initiative

Speaker (Affiliation): Johannes Andersen (NOT & ASTRONET Board)

Abstract: The ASTRONET consortium aims to establish a comprehensive, long-term planning for all of European astronomy. Three years old, it has matured substantially: Nearly all significant European communities are involved; the Science Vision and Infrastructure Roadmap have been completed and published; and we are moving into the phase of implementing their recommendations. The talk will summarise the current status of ASTRONET and outline some of the options for the future.

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Date: 8 Jul (Tuesday)

Time: 15:00

Place: 6th floor meeting room, Mayantigo building

Title: Who is this girl and what is she doing here?

Speaker (Affiliation): Sarah Barker (University of Sheffield and ING)

Abstract: As part of my masters degree in Physics and Astrophysics with the University of Sheffield, I was lucky enough to be given the opportunity to apply to spend my final year here at the ING. For the past 10 months I have been working as a Support Astronomer at the Isaac Newton Telescope, whilst simultaneously studying for my degree. This talk gives an overview of the work I have done, and projects I have been involved with during this time. Particular attention is paid to Broad Absorption Line Quasars, my main research interest this year. By using the level of ionisation of these ‘BAL QSOs’, I have estimated the distance to which high-velocity outflows extend from the centre of these quasars, and the results will be discussed in this talk.

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Presentation: PPT

Date: 8 Jul (Tuesday)

Time: 15:00

Place: 6th floor meeting room, Mayantigo building

Title: ARCS: the Asiago Red Clump Spectroscopic Survey and its applications

Speaker (Affiliation): Marica Valentini (Astronomical Observatory of Padova and ING)

Abstract: My PhD project is about a further investigation and characterization of local Red Clump Stars, in order to use them as distance indicators and tracers of Milky Way structure and kinematics. The project started in 2006 with ARCSs (Asiago Red Clump Spectroscopic survey), and then it will be fulfilled with data from Rave survey. Now ARCS survey is ended, and I personally observed about 500 local Red Clump stars with the Echelle spectrograph, mounted in the Asiago 1.82m telescope. The data reduction and analisys ended in these days, at last. The result of this work will be the publication of one of the biggest Red Clump stars catalogue, containing radial velocities and atmospherical parameters of the selected sample. The analysis of this data also led to a calibration of a reliable function of Mv dependent on [M/H], log(g) and Teff, useful for using RC stars as distance indicators. In the next future my project will continue with the application of the ARCSs and Rave data on classical problems of Milky Way structure and cinematics, as streams detection, local velocity escape calculation and detection of dark matter.

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Date: 16 Apr (Wednesday)

Time: 16:00

Place: 6th floor meeting room, Mayantigo building

Title: AGN feedback in compact radio sources

Speaker (Affiliation): Joanna Holt (Sterrewacht Leiden)

Abstract: Over the last decade or so, it has become clear that AGN feedback plays a key role in galaxy evolution. However, due to the lack of observational results, feedback is often inserted into the models as a black box. Theroetical analyses by e.g. Silk & Rees and Fabian give good descriptions of the feedback process, although these scenarios assume the feedback process is dominated by quasar-induced winds. Whilst this may be true for radio-quiet AGN, in radio-loud AGN the expanding radio jets may also provide a significant contribution to the overall feedback of the AGN. In this talk I will discuss our recent study of the emission line outflows in compact radio sources. Compact radio sources are ideal objects in which to study AGN feedback as i) the compact radio source highlights the presence of a young, recently triggered AGN which still retains it's natal cocoon and ii) these sources contain all of the possible outflow driving mechanisms (AGN winds/starburst winds/radio jet activity) and are therefore the only objects in which the relative importance of all of the different feedback effects can be studied.

Slides: PPT Additional material: movie and movie player

Presentation:

Date: 27 Mar (Thursday)

Time: 16:00

Place: 6th floor meeting room, Mayantigo building

Title: Galaxy formation - the fossil record of nearby stars

Speaker (Affiliation): Klaus Fuhrmann (ING)

Abstract: High-resolution spectroscopy of nearby solar-type stars implies that the Galaxy became reality 13 Gyr ago with the implementation of a massive, rotationally-supported population of thick-disk stars. The very high star formation rate in that phase gave rise to a rapid metal enrichment and an expulsion of gas in supernovae-driven Galactic winds, but was followed by a star formation gap for no less than three billion years. In a second phase, the thin disk -- our "familiar Milky Way" -- came on stage. Nowadays it traces the bright side of the Galaxy, but it is also embedded in a huge coffin of dead thick-disk stars that account for a large amount of baryonic dark matter and that particularly challenge the hierarchical cold-dark-matter-dominated formation picture for our parent spiral.

Slides: Tar file

Presentation:

Date: 19 Mar (Wed)

Time: 12:00

Place: 6th floor meeting room, Mayantigo building

Title: Galaxies with star-forming satellites: How typical is the Milky Way system?

Speaker (Affiliation): Phil James (Astrophysics Research Institute at Liverpool John Moores University)

Abstract:

Slides: PPT | PDF

Presentation:

Date: 13 Mar (Thursday)

Time: 12:00

Place: 6th floor meeting room, Mayantigo building

Title: Sigma Orionis: A New Hope

Speaker (Affiliation): José A. Caballero (Universidad Complutense de Madrid)

Abstract: The sigma Orionis cluster is very young (about 3 My) and relatively nearby (a bit less than 400 pc). It takes the name from the Trapezium-like star system sigma Ori, which illuminates the mane of the Horsehead Nebula and is the fourth brightest star in the Orion Belt. The cluster is a well-equiped laboratory to investigate the stellar and substellar formation. It contains OB-type stars, Herbig-Haro objects, strong X-ray sources, peculiar multiple systems, Class I object candidates, highly photometric variable brown dwarfs, and the largest known population of isolated planetary-mass objects. I will give a general review on the sigma Orionis cluster, describing from the O9.5V star in its centre (M ~ 18 M_sun), to S Ori 70, that is to date the less-massive isolated body directly imaged out of the Solar System (M ~ 3 M_Jup).

Slides: PPT

Presentation:

Date: 18 Feb (Monday)

Time: 12:00

Place: Meeting room, Fundación Galileo Galilei (Rambla José Ana Fernández Pérez, 7; San Antonio - Breña Baja)

Title: CTIO and the US System of Telescopes

Speaker (Affiliation): Alistair Walker (CTIO, NAO)

Abstract: I will describe the present status of the telescopes and instrumentation at CTIO, and then explain how the US National Optical Observatories (CTIO, KPNO) plan to evolve over the next decade, in the face of the competing demands of the new 'super projects' for both funding and support observations. This has led to the concept of the 'US System of Telescopes', designed to optimize the range of facilities available for US astronomers.

Slides: PDF | PPT

Presentation: