A5076048337- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Astrophysics and Star Formation Studies
- Galaxies: Formation, Evolution, Phenomena
- Astro and Planetary Science
- Astronomical Observations and Instrumentation
- Gamma-ray bursts and supernovae
- Adaptive optics and wavefront sensing
- CCD and CMOS Imaging Sensors
- History and Developments in Astronomy
- Calibration and Measurement Techniques
- Spectroscopy and Laser Applications
- Astrophysical Phenomena and Observations
- Atomic and Molecular Physics
- Atmospheric Ozone and Climate
- Astrophysics and Cosmic Phenomena
- Solar and Space Plasma Dynamics
- Particle Detector Development and Performance
- Photocathodes and Microchannel Plates
- Radio Astronomy Observations and Technology
- Optical Systems and Laser Technology
- Infrared Target Detection Methodologies
- Scientific Research and Discoveries
- Cosmology and Gravitation Theories
- Molecular Spectroscopy and Structure
European Southern Observatory
2013-2024
Space Telescope European Coordinating Facility
2002-2011
Istituto Nazionale di Fisica Nucleare
2011
Kitt Peak National Observatory
2005
Optica
2005
Bond University
1992-1993
Australian Astronomical Observatory
1985-1989
University of Groningen
1989
University of Manchester
1980-1985
The High-Z Supernova Search is an international collaboration to discover and monitor Type Ia supernovae (SNe Ia) at z > 0.2 with the aim of measuring cosmic deceleration global curvature. Our has pursued a basic understanding in nearby universe, discovering observing large sample objects developing methods measure accurate distances SNe Ia. This paper describes extension this program ≥ 0.2, outlining our search techniques follow-up program. We have devised high-throughput filters that...
The VST Photometric Halpha Survey of the Southern Galactic Plane and Bulge (VPHAS+) is surveying southern Milky Way in u, g, r, i at 1 arcsec angular resolution. Its footprint spans latitude range -5 < b +5 all longitudes south celestial equator. Extensions around Centre to latitudes +/-10 bring much Bulge. This ESO public survey, begun on 28th December 2011, reaches down 20th magnitude (10-sigma) will provide single-epoch digital optical photometry for 300 million stars. observing strategy...
We present and discuss the photometric spectroscopic evolution of peculiar SN 1998bw, associated with GRB 980425, through an analysis optical near-IR data collected at ESO-La Silla. The data, spanning period from day -9 to +376 (relative B maximum), have shown that this supernova (SN) was unprecedented, although somewhat similar 1997ef. Maximum expansion velocities as high 3 × 104 km s-1 some extent mask its resemblance other Type Ic SNe. At intermediate phases, between photospheric fully...
The methods and techniques for the slitless spectroscopy software aXe, which was designed to reduce data from various modes of Hubble Space Telescope instruments, are described. aXe can treat spectra different instruments such as ACS, NICMOS, WFC3 through use a configuration file that contains all instrument-dependent parameters. basis spectral extraction within position, morphology, photometry objects on companion direct image. Several aspects spectroscopy, overlap spectra, an dependent...
Optical and ultraviolet spectroscopy obtained with the Hubble Space Telescope Faint Object Spectrograph at three locations in central H II complex of amorphous starburst galaxy NGC 5253 confirms an apparent area enhanced nitrogen abundance seen ground-based studies. At two positions, N appears by a factor 3 [log (N/O) = -0.85] compared to third location 50 pc away where measured is typical metal-poor galaxies -1.30]. No other elemental species shows spatial fluctuations, including C as from...
We present results from a search for high-redshift J--band ``dropout'' galaxies in the portion of GOODS southern field that is covered by extremely deep imaging Hubble Ultradeep Field (HUDF).Using observations at optical, near-infrared and mid-infrared wavelengths Spitzer Space Telescopes ESO-VLT, we very massive high redshifts find one particularly remarkable candidate. Its spectral energy distribution consistent with galaxy z ~ 6.5 stellar mass 6x10e11 M(sun) (for Salpeter IMF). interpret...
We present grism spectra taken with the Advanced Camera for Surveys to identify 29 red sources (i'-z') > 0.9 in Hubble Ultra Deep Field (HUDF). Of these 23 are found be galaxies at redshifts between z=5.4 and 6.7, identified by break 1216 angstrom due IGM absorption; two late type dwarf stars colors; four colors spectral shape similar dust reddened or old z~1-2. This constitutes largest uniform, flux-limited sample of spectroscopically confirmed such faint fluxes z'<27.5. Many also...
As part of the Accretion Discs in H$\alpha$ with OmegaCAM (ADHOC) survey, we imaged r, i and H-alpha a region 12x8 square degrees around Orion Nebula Cluster. Thanks to high-quality photometry obtained, discovered three well-separated pre-main sequences color-magnitude diagram. The populations are all concentrated towards cluster's center. Although several explanations can be invoked explain these left two competitive, but intriguing, scenarios: population unresolved binaries an exotic mass...
The light curve of a distant Type Ia supernova acts like clock that can be used to test the expansion universe. SN 1995K, at spectroscopic redshift z = 0.479, provides one first meaningful data sets for this test. We find all aspects 1995K resemble local events when is dilated by (1 + z), as prescribed cosmological expansion. In static, nonexpanding universe, would represent unique object with spectrum identifying it regular but light-curve shape and luminosity do not follow well-established...
We present deep unbiased spectroscopy of the Hubble Ultra Deep Field (UDF) carried out using slitless grism mode Advance Camera for Surveys on Space Telescope (HST). The GRIsm ACS Program Extragalactic Science (GRAPES) achieves continuum detection as faint $z_{AB}=27.2$ 40 orbits ($9.2 \times 10^4$ seconds) HST. data were taken at four orientation angles to correct overlap spectra. GRAPES provide a unique, uninterrupted, low resolution (R=100) spectral coverage $5500Å< λ< 10500Å$, and...
La region centrale ionisee du noyau de la galaxie a flambee NGC 5253 est tracee par une technique d'imagerie spectrometrique. Les traces montrent des fluctuations point-a-point dans l'extinction et les rapports raies superieures aux erreurs mesure, maniere similaire d'autres galaxies qui avaient ete tracees avec meme Une dizaine regions sont definies sur l'aire spectres ces analyses
Long-slit spectra at several positions on the large, faint haloes of NGC 6543 and 6826, from IPCS CCD detectors, are analysed to give average properties these two regions. Comparison halo bright core shows that emission is thermal not reflection. Average masses estimated. The [O III] electron temperature higher in each than its central nebula; we find Te (halo) = 14 700 13 000 K for respectively. mass ratios (halo/core) range 2.9–10.2 0.07–2.24 respectively, absolute Hβ flux measurements...
ABRIDGED: A detailed 2D study of the central region NGC5253 has been performed to characterize stellar and ionized gas structure as well extinction distribution, physical properties kinematics in ~210pc x 130pc. We utilized optical integral field spectroscopy (IFS) data obtained with FLAMES. map for shows that largest is associated prominent Giant HII region. There an offset ~0.5" between peak continuum agreement findings infrared. found stars suffer less than by a factor 0.33. The...
A study of the blue compact dwarf (BCD) galaxy Mrk 996 based on high resolution optical VLT VIMOS integral field unit spectroscopy is presented. displays multi-component line emission, with most profiles consisting a narrow, central Gaussian an underlying broad component. The HI Balmer component splits into two separate components inside 1".5 radius from nucleus; these are attributed to two-armed mini-spiral. rotation curve derived H\alpha narrow yields total mass 5x10^8 Msol within 3 kpc....
Abstract NGC 5128 at 3.8 Mpc is the nearest large elliptical galaxy and ideally suited to a detailed study of its planetary nebula population. Two spectroscopic programmes are summarised. More than 1200 PNe candidates known from imaging campaigns in accurate radial velocities 1070 have been measured with VLT FLAMES/Giraffe spectrometer. From these data variety studies kinematics enabled, such as search for PN sub-groups, representing relics accretion small galaxies. Emission line spectra...
Galaxies at high redshifts provide a valuable tool to study cosmic dawn, and therefore it is crucial reliably identify these galaxies. Here, we present an unambiguous first simultaneous detection of both the Lyman-alpha emission Lyman break from z = 7.512+/- 0.004 galaxy, observed in Faint Infrared Grism Survey (FIGS). These spectra, taken with G102 grism on Hubble Space Telescope (HST), show significant line (6 sigma) multiple observational position angles (PA), total integrated Ly{\alpha}...
Future galaxy redshift surveys aim to measure cosmological quantities from the power spectrum. A prime example is detection of baryonic acoustic oscillations, providing a standard ruler dark energy equation state, w(z), high precision. The strongest practical limitation for these experiments how quickly accurate redshifts can be measured sufficient galaxies map large-scale structure. promising strategy target emission-line (i.e. star-forming) at (z∼ 0.5–2); not only space density this...
Using VLT/FLAMES optical integral field unit observations, we present the first spatially resolved spectroscopic study of well known blue compact galaxy Haro11, thought to be a local analogue high redshift Lyman Break Galaxies. Haro11 displays complex emission line profiles, consisting narrow (FWHM<200 km/s) and broad (FWHM 200-300 components. We identify three distinct knots kinematically connected one another. A chemodynamical analysis is presented, revealing that ionic elemental...
We present Gemini-S/GMOS-IFU optical spectroscopy of four regions near the centre nearby (3.8 Mpc) dwarf starburst galaxy NGC 5253. This is famous for hosting a radio supernebula containing two deeply embedded massive super star clusters, surrounded by region enhanced nitrogen abundance that has been linked to presence WR stars. detected 11 distinct sources red bump (CIV) emission over 20" (~350 pc) area, each consistent with ~1 WCE-type star. WC stars are not found coincident supernebula,...