A5039788037- Astronomy and Astrophysical Research
- Galaxies: Formation, Evolution, Phenomena
- Stellar, planetary, and galactic studies
- Astronomical Observations and Instrumentation
- Adaptive optics and wavefront sensing
- CCD and CMOS Imaging Sensors
- Gamma-ray bursts and supernovae
- Calibration and Measurement Techniques
- Scientific Research and Discoveries
- Astrophysics and Star Formation Studies
- Radio Astronomy Observations and Technology
- Astrophysics and Cosmic Phenomena
- Astrophysical Phenomena and Observations
- History and Developments in Astronomy
- Cosmology and Gravitation Theories
- Spectroscopy and Laser Applications
- Solar and Space Plasma Dynamics
- Geophysics and Gravity Measurements
- Particle Detector Development and Performance
- Scientific Computing and Data Management
- Computational Physics and Python Applications
- Astro and Planetary Science
- Statistical and numerical algorithms
- Atmospheric Ozone and Climate
- Dark Matter and Cosmic Phenomena
European Southern Observatory
2012-2024
Space Telescope European Coordinating Facility
1999-2008
Wesleyan University
1997
Elkhorn Slough Foundation
1997
Max Planck Institute for Extraterrestrial Physics
1997
Center for Astrophysics Harvard & Smithsonian
1995
Valongo Observatory
1994
National Observatory
1994
In this paper we describe the first data release of UltraVISTA near-infrared imaging survey COSMOS field. We summarise key goals and design provide a detailed description our reduction techniques. stacked, sky-subtracted images in YJHKs narrow-band filters constructed from collected during year observations. Our stacked reach 5σAB depths an aperture 2″ diameter ~25 Y ~24 JHKs bands all have sub-arcsecond seeing. To 5σ limit, Ks catalogue contains 216 268 sources. carry out series quality...
Data from complex modern astronomical instruments often consist of a large number different science and calibration files, their reduction requires variety software tools. The execution chain the tools represents workflow that needs to be tuned supervised, by individual researchers are not necessarily experts for any specific instrument. efficiency data can improved using automatic workflows organise execute sequence steps. To realize such gains, we designed system allows intuitive...
The blazar 3C 279, one of the brightest identified extragalactic objects in γ-ray sky, underwent a large (factor ~10 amplitude) flare γ-rays toward end 3 week pointing by Compton Gamma Ray Observatory (CGRO), 1996 January-February. peak represents highest intensity ever recorded for this object. During high state, extremely rapid variability was seen, including an increase factor 2.6 ~8 hr, which strengthens case relativistic beaming. Coordinated multifrequency observations were carried out...
We analyze the photometric properties of a sample Sbc-Sc galaxies with known redshifts, single-dish H I profiles, and CCD band images. derive laws that relate measured isophotal radius at μ_I_ = 23.5, magnitude, scale length, flux to face-on aspect. find spiral be substantially less transparent than suggested in most previous determinations, but not as opaque claimed by Valentijn [Nature, 346, 153 (1990)). Regions disk farther two or three lengths from center are close completely...
Context. Astronomical data reduction is usually done via processing pipelines that consist of a series individual steps can be executed one at time. These are then strung together into workflows and fed with to address particular goal. Examples such pipeline goals the quality control incoming from telescopes, unsupervised production science calibration products for an archive, supervised serve specific scientist. For each these goals, need developed. evolve when pipeline, observing...
view Abstract Citations (213) References (45) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS The I band Tully-Fisher relation for cluster galaxies: data presentation. Giovanelli, R. ; Haynes, M. P. Herter, T. Vogt, N. Wegner, G. Salzer, J. da Costa, L. Freudling, W. Observational parameters which can be used redshift-independent distance determination using the (TF) technique are given \ntot spiral galaxies in fields of 24 clusters or groups. photometry full...
Infrared I band photometry and velocity widths for galaxies in 24 clusters, with radial velocities between 1,000 10,000 \kms, are used to construct a template Tully-Fisher (TF) relation. The sources of scatter the TF diagram analyzed detail; it is shown that common practice referring single figure incorrect can lead erroneous bias corrections. Biases resulting from sample incompleteness, catalog inaccuracies, cluster size other sources, as well dependences parameters on morphological type...
We present a luminosity function for Hα emission from galaxies at redshifts between 0.7 and 1.9 based on slitless spectroscopy with the near-infrared camera multiobject spectrometer Hubble Space Telescope. The is well fit by Schechter over range 6 × 1041 < L41 2 1043 ergs s-1 L* = 7 1042 ϕ* 1.7 10-3 Mpc-3 H0 50 km Mpc-1 q0 0.5. derive volume-averaged star formation rate z 1.3 ± 0.5 of 0.13 M☉ yr-1 without correction extinction. that we ~6500 Å factor 3 higher than deduced 2800 continua. If...
Of the blazars detected by EGRET in GeV γ-rays, 3C 279 is not only best observed but also one of monitored at lower frequencies. We have assembled 11 spectra, from GHz radio through time intervals observations. Although some data appeared previous publications, most are new, including taken during high states early 1999 and 2000. All spectra show substantial γ-ray contribution to total luminosity object; a state, dominates over that all other frequencies factor more than 10. There no clear...
<i>Context. <i/> Narrow-band surveys to detect Ly<i>α<i/> emitters are powerful tools for identifying high, and very redshift galaxies. Although samples increasing at redshifts , the nature of these galaxies is still poorly known. The number detected below also small.<i>Aims. We study properties compare them with those emitters.<i>Methods. present narrow-band imaging made MPG/ESO 2.2m telescope WFI (Wide Field Imager) detector. Using this data, we have searched emission-line objects. find...
The Arecibo Ultra-Deep Survey (AUDS) combines the unique sensitivity of telescope with wide field L-band Feed Array (ALFA) to directly detect 21 cm |${\rm H\,{\small i}}$| emission from galaxies at distances beyond local Universe bounded by lower frequency limit ALFA (z = 0.16). AUDS has collected 700 h integration time in two fields a combined area 1.35 deg2. In this paper, we present data 60 per cent total survey, corresponding level 80 μJy. We discuss reduction, search for galaxies,...
A compilation of 21 cm line spectral parameters specifically designed for application the Tully-Fisher (TF) distance method is presented 1201 spiral galaxies, primarily field Sc which optical I-band photometric imaging also available. New H I spectra have been obtained 881 galaxies. For an additional 320 available in a digital archive reexamined to allow single algorithm derivation TF velocity width parameter. used that provides robust measurement rotational and permits estimate error on...
A sample of more than 1700 galaxies for which I band CCD images, redshifts, and H lines velocity widths are available is used to study the dependence on luminosity main photometric parameters spiral disks. For some derivations, complemented by other data in public domain. The impact selection criteria distribution function observed monitored vis-a-vis visibility functions inspecting properties Monte Carlo simulations data. Significant dependences found disk central surface brightness...
The use of the Tully-Fisher (TF) relation for determination H0 relies on availability an adequate template TF and reliable primary distances. Here we a with best available kinematical zero point, obtained from sample 24 clusters galaxies extending to cz ~ 9000 km s-1, most recent set Cepheid distances fit use. combination these two ingredients yields = 69 ± 5 s-1 Mpc-1. approach is significantly more accurate than common application single cluster (e.g., Virgo, Coma) samples.
We have obtained low-resolution near infrared spectra of three QSOs at 5.7 < z 6.3 using the NICMOS instrument Hubble Space Telescope. The cover rest-frame ultraviolet emission objects between lambda_rest ~ 1600A - 2800A. Fe II emission-line complex 2500A is clearly detected in two objects, and possibly third. strength this ratio its integrated flux to that Mg lambda 2800 are comparable values measured for lower redshifts, consistent with Fe/Mg abundance ratios or above solar value. There...
While the near-infrared wavelength regime is becoming more and important for astrophysics there a marked lack of spectrophotometric standard star data that would allow flux calibration such data. Furthermore, calibrating medium- to high-resolution \'echelle spectroscopy challenging even in optical range, because available are often too coarsely sampled. We will provide reference users derive response curves from 300nm 2500nm spectroscopic medium high resolution, including those taken with...
Context. Classical Cepheids are primary distance indicators and a crucial stepping stone in determining the present-day value of Hubble constant H 0 to precision accuracy required constrain apparent deviations from ΛCDM Concordance Cosmological Model. Aims. We measured iron oxygen abundances statistically significant sample 89 Large Magellanic Cloud (LMC), one anchors local scale, quadrupling prior including 68 70 used by SH0ES program. The goal is extent which luminosity influenced their...
Context . The study of asteroids, particularly near-Earth is key to gaining insights into our Solar System and can help prevent dangerous collisions. Beyond finding new objects, additional observations known asteroids will improve knowledge their orbit. Aims We have developed an automated pipeline process search for asteroid trails in images taken with OmegaCAM, the wide- field imager mounted on VLT Survey Telescope (VST), European Southern Observatory’s Cerro Paranal. inputs a FITS image...
Properties derived from the analysis of photometric I-band imaging observations are presented for 1727 inclined spiral galaxies, mostly types Sbc and Sc. The reduction, parameter extraction, error estimation procedures discussed in detail. asymptotic behavior magnitude curve growth radial variation ellipticity position angle used combination with linearity surface brightness falloff to fit disk portion profile. Total magnitudes calculated by extrapolating detected profile a radius eight...
Context.This is the first paper of a series describing our measurement weak lensing by large-scale structure, also termed “cosmic shear”, using archival observations from Advanced Camera for Surveys (ACS) on board Hubble Space Telescope (HST).
We analyse a sample of 16 absorption systems intrinsic to long-duration gamma-ray burst (GRB) host galaxies at z ≳ 2 for which the metallicities are known. compare relation between metallicity and cold gas velocity width this that QSO-DLAs (quasi-stellar object–damped Lyman α), find complete agreement. then redshift evolution mass–metallicity our also GRB hosts favour late onset evolution, around ≈2.6. compute predicted stellar masses using prescription determined from QSO-DLA samples...
We present a new reconstruction of the mass density and peculiar velocity fields in nearby universe using recent measurements Tully-Fisher distances for sample late spirals. find significant differences between our reconstructed those obtained earlier work: overdensities tend to be more compact while underdense regions, consisting individual voids, are abundant. Our results suggest that voids observed redshift surveys galaxies represent real underlying matter distribution. While we detect...
A compilation of HI line fluxes, systemic velocities and widths is presented for \Ndet detected galaxies, mostly in the vicinities 30 nearby rich clusters out to a redshift z ~ .04, specifically use applications Tully-Fisher distance method. New 21 cm profiles have been obtained 500 galaxies 27 Abell visible from Arecibo. Upper limits are also \Nnod which emission was not detected. In order provide homogeneous width determination optimized studies, these new data supplemented by reanalysis...
We present a survey of all 3CR sources imaged with ISOCAM onboard the Infrared Space Observatory (ISO). For source, we spatially integrated mid--infrared (MIR, 5 - 18mic.) fluxes measured from newly calibrated images. In total, detected 68 AGN catalogue, at redshifts z < 2.5. The one highest redshift is 4C+72.26 = 3.53. data are combined other photometric measurements to construct spectral energy distribution (SED) optical radio wavelengths. order describe dust emission apply new...