- ID:
- ivo://CDS.VizieR/J/ApJ/497/188
- Title:
- A103, A118 and A114 morphological studies
- Short Name:
- J/ApJ/497/188
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a program to study the detailed morphologies of galaxies in intermediate-redshift clusters and hence understand the physical origin of the enhanced star formation seen in the environments at earlier epochs. Deep, high-resolution imagery has been obtained of three rich clusters, AC 103, AC 118 and AC 114 at z=0.31, through the R (F702W) filter of the Wide Field Planetary Camera (WFPC2) of the Hubble Space Telescope (HST).
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- ID:
- ivo://CDS.VizieR/J/AJ/117/247
- Title:
- Ages for globular clusters in the halo
- Short Name:
- J/AJ/117/247
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have used the Wide Field Planetary Camera 2 on the Hubble Space Telescope to obtain photometry of the outer halo globular clusters Palomar 3, Palomar 4, and Eridanus. These three are classic examples of the "second-parameter" anomaly because of their red horizontal-branch morphologies in combination with their low-to-intermediate metallicities. Our color-magnitude diagrams (CMDs) in V, V - I reach V_lim_ {=~} 27.0, clearly delineating the subgiant and turnoff regions and about 3 mag of the unevolved main sequences.
- ID:
- ivo://CDS.VizieR/J/A+A/324/915
- Title:
- Blue stragglers in M3
- Short Name:
- J/A+A/324/915
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The core of the Galactic Globular Cluster M 3 (NGC 5272) has been observed with the WFPC2 through the filters F255W, F336W, F555W, and F814W. Using these observations along with a thorough reanalysis of earlier catalogs, we have produced a catalog of blue straggler stars (BSS) spanning the cluster. Earlier studies and the fainter part of our sample suffer severe selection biases. Our analysis is based on a more reliable bright global sample of 122 BSS. We confirm earlier suggestions that the radial BSS distribution in M 3 is bimodal. It is strongly peaked in the center, has a clear dip 100-200" from the center, and rises again at larger radii. The observed distribution agrees with the dynamical model of Sigurdsson et al. (1994ApJ...431L.115S) which takes into account both star collisions and merging of primordial binaries for the origin of BSS. The observed luminosity functions of BSS in the inner and outer parts of the cluster are different. Interpreting these using the models of Bailyn & Pinsonneault (1995ApJ...439..705B), we suggest that the BSS in the inner cluster are formed by stellar collisions and those in the outer cluster from merging primordial binaries.
- ID:
- ivo://CDS.VizieR/J/ApJ/522/802
- Title:
- Cepheid calibration of SN 1989B in NGC 3627
- Short Name:
- J/ApJ/522/802
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Repeated imaging observations have been made of NGC 3627 with the Hubble Space Telescope in 1997 - 1998 over an interval of 58 days. Images were obtained on 12 epochs in the F555W band and on five epochs in the F814W band. The galaxy hosted the prototypical, "Branch normal," type Ia supernova SN 1989B. A total of 83 variables have been found, of which 68 are definite Cepheid variables with periods ranging from 75 to 3.85 days. The dereddened distance modulus is determined to be (m-M)_o_=30.22{+/-}0.12 (internal uncertainty) using a subset of the Cepheid data whose reddening and error parameters are secure.
- ID:
- ivo://CDS.VizieR/J/ApJ/475/469
- Title:
- Composite HST Spectrum of Quasars
- Short Name:
- J/ApJ/475/469
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We construct a composite quasar spectrum from 284 HST FOS spectra of 101 quasars with redshifts z>0.33. The spectrum covers the wavelengths between 350 and 3000A in the rest frame, with a peak S/N level of ~130 per A at ~1200A. Since ~90% of the sample quasars have redshift z<1.5, the spectrum is suitable for studying the wavelength region shortward of Ly{alpha} without large effects from intervening Ly{alpha} forest absorption. Data in the waveband between 350 and 600A are mainly from the spectra of z>1.5 quasars, for which significant corrections for the accumulated Lyman-series line and continuum absorption have been applied. There is a significant steepening of the continuum slope around 1050A. The continuum between 1050 and 2200A can be modeled as a power law f_{nu} proportional to {nu}_{alpha}_ with {alpha}=-0.99+/-0.05. For the full sample the power-law index in the extreme ultraviolet (EUV) between 350 and 1050A is {alpha}=-1.96+/-0.15. For the radio-loud subsample (60 objects), the EUV spectral index is {alpha}~=-2.2, while for the radio-quiet subsample (41 objects) it is {alpha}~=-1.8. The continuum flux in the wavelengths near the Lyman limit shows a depression of ~10%. The break in the power-law index and the slight depression of the continuum near the Lyman limit are features expected in Comptonized accretion-disk spectra. Comptonization produces a power-law tail in the wavelength band shortward of 1000A and smears out the Lyman-limit edge of the intrinsic accretion-disk spectrum. In the EUV waveband, we detect several possible emission features, including one around 690A that may be O III + N III produced by the Bowen fluorescence effect. Comparing our composite spectrum with one made at higher redshifts by Francis et al. (1991ApJ...373..465F), we find that the equivalent widths of Ly{alpha} and high-ionization emission lines are larger in our sample, reflecting a known luminosity dependence. The equivalent widths of low-ionization lines do not exhibit such a dependence, suggesting that the quasar EUV continuum above ~50eV is steeper at higher luminosity. Radio-quiet quasars appear to show a slightly harder continuum and lower ionization levels in their emission lines.
- ID:
- ivo://CDS.VizieR/J/AJ/118/2071
- Title:
- ESO 565-11 UBVI(c) photometry
- Short Name:
- J/AJ/118/2071
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present multiband Wide Field Planetary Camera 2 images of the central regions of ESO 565-11, a peculiar southern barred galaxy recently shown to have the largest known example of a circumnuclear starburst ring. We also present ground-based near-infrared H-band imaging and photometry of the galaxy. The results provide an interesting picture of the star-forming ring and its environment.
- ID:
- ivo://CDS.VizieR/J/AJ/118/1671
- Title:
- Fornax cluster 4 VI photometry
- Short Name:
- J/AJ/118/1671
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using observations from the Hubble Space Telescope archive, color-magnitude diagrams (CMDs) have been constructed for globular cluster 4 in the Fornax dwarf spheroidal galaxy and its surrounding field.
- ID:
- ivo://CDS.VizieR/J/ApJ/504/113
- Title:
- F175W and F275W photometry of M31 and M32
- Short Name:
- J/ApJ/504/113
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present Faint Object Camera (FOC) ultraviolet images of the central 14"x14" of Messier 31 and Messier 32. The hot stellar populations detected in the composite UV spectra of these nearby galaxies are partially resolved into individual stars, and their individual colors and apparent magnitudes are measured. We detect 433 stars in M31 and 138 stars in M32, down to detection limits m_F275W_=25.5mag and m_F175W_=24.5mag.
- ID:
- ivo://CDS.VizieR/J/AJ/112/359
- Title:
- Galaxies in the Hubble Deep Field
- Short Name:
- J/AJ/112/359
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of morphological and color data for galaxies with 21<I_814<25mag in the Hubble Deep Field (Williams et al. 1996, in Science with the Hubble Space Telescope II). Galaxies have been inspected and (when possible) independently visually classified on the MDS and DDO systems. Measurements of central concentration and asymmetry are also included in the catalog. The fraction of interacting and merging objects is seen to be significantly higher in the Hubble Deep Field than it is among nearby galaxies. Barred spirals are essentially absent from the deep sample. The fraction of early-type galaxies in the Hubble Deep Field is similar to the fraction of early-types in the Shapley-Ames Catalog, but the fraction of galaxies resembling archetypal grand-design late-type spiral galaxies is dramatically lower in the distant HDF sample.
10. Globulars in M31
- ID:
- ivo://CDS.VizieR/J/AJ/114/1488
- Title:
- Globulars in M31
- Short Name:
- J/AJ/114/1488
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present deep (V=~27) V- and I-band stellar photometry of G302 and G312, two globular star clusters in the halo of M31. These data were obtained using the Hubble Space Telescope's Wide Field/Planetary Camera 2. We find iron abundances of [Fe/H]=-1.85+/-0.12 for G302 and [Fe/H]=-0.56+/-0.03 for G312, consistent with spectroscopic measurements. The color-magnitude diagrams for each cluster show no evidence for an intermediate-aged population of stars, or a second parameter effect in the morphology of the horizontal branch. G302 shows no evidence for a color gradient but the inner regions of G312 are bluer than the outer regions. G312 shows no evidence of ellipticity or an extended halo of stars. G302 has a projected ellipticity of {epsilon}=0.195+/-0.012 with the projected major axis oriented towards the center of M31. G302 also shows evidence of an extended asymmetric stellar halo extending to at least twice the fitted Michie-King tidal radius. The amount of mass beyond the tidal radius of G302 is consistent with the stellar escape rates which have been predicted by N-body simulations of globular clusters in the Galactic tidal field. (c) 1997 American Astronomical Society.
- ID:
- ivo://CDS.VizieR/VII/246
- Title:
- GOODS Morphological Catalog
- Short Name:
- VII/246
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present below the morphological catalogs of galaxies in the GOODS North and South fields, as determined visually by R. S. Ellis with a magnitude limit from HST/ACS imaging of z<22.5 (AB).
- ID:
- ivo://CDS.VizieR/J/ApJ/551/111
- Title:
- HDF early-type and spiral galaxies
- Short Name:
- J/ApJ/551/111
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We analyze the internal optical colors of a complete sample of I_814_<24mag early-type and spiral galaxies from the northern and southern Hubble Deep Fields (HDF). The subset of galaxies in the HDF-North are also investigated in the near-infrared using NICMOS photometry. We compare the central (inner 5% radius) colors of those spirals with clearly visible bulges with the integrated colors of ellipticals in our sample.
- ID:
- ivo://CDS.VizieR/J/A+A/364/517
- Title:
- HDF-N spiral and irregular galaxies
- Short Name:
- J/A+A/364/517
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We analyze a morphologically-selected complete sample of 52 late-type (spiral and irregular) galaxies in the Hubble Deep Field North with total K-magnitudes brighter than K=20.47 and typical redshifts z~0.5 to 1.4. This sample exploits in particular the ultimate imaging quality achieved by HST in this field, allowing us to clearly disentangle the early- from late-type galaxy morphologies, based on accurate profiles of the surface brightness distributions.
- ID:
- ivo://CDS.VizieR/J/ApJ/513/34
- Title:
- HDF photometric redshifts catalog
- Short Name:
- J/ApJ/513/34
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using the newly available infrared images of the Hubble Deep Field in the J, H, and K bands and an optimal photometric method, we have refined a technique to estimate the redshifts of 1067 galaxies. A detailed comparison of our results with the spectroscopic redshifts in those cases where the latter are available shows that this technique gives very good results for bright enough objects [AB(814nm)<26.0]. From a study of the distribution of residuals [{Delta}z_rms_/(1+z)~0.1 at all redshifts], we conclude that the observed errors are mainly due to cosmic variance. This very important result allows for the assessment of errors in quantities to be directly or indirectly measured from the catalog. We present some of the statistical properties of the ensemble of galaxies in the catalog, and we finish by presenting a list of bright high-redshift (z~5) candidates extracted from our catalog together with recent spectroscopic redshift determinations confirming that two of them are at z=5.34 and z=5.60.
- ID:
- ivo://CDS.VizieR/J/A+AS/145/111
- Title:
- HDF-South catalogue of galaxies
- Short Name:
- J/A+AS/145/111
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalogue of galaxies in the HDF-S, created using the public version 1 images of the WFPC2 data. We created a catalogue with 4 pass-band (I(814), V(606), B(450), U(300). In V(606), B(450), U(300) and I(814), for each galaxy the catalogue gives photometric parameters. For the I(814), we estimated also the colours and for I(814)<26, the petrosian radius, the mean surface brightness within the petrosian radius, light concentration indexes, that is C_eta_ and C_abr_, and the asymmetry index as computed by Abraham software.
- ID:
- ivo://CDS.VizieR/J/ApJ/538/493
- Title:
- HDF-South NICMOS field
- Short Name:
- J/ApJ/538/493
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of photometry and photometric redshifts of 335 faint objects in the Hubble Deep Field South (HDF-S) near-infrared camera and multiobject spectrograph (NICMOS) field. The analysis is based on (1) infrared images obtained with the Hubble Space Telescope (HST) using the NICMOS with the F110W, F160W, and F222M filters; (2) an optical image obtained with HST using the Space Telescope Imaging Spectrograph with no filter; and (3) optical images obtained with the European Southern Observatory Very Large Telescope with U, B, V, R, and I filters. The primary utility of the catalog of photometric redshifts is as a survey of faint galaxies detected in the NICMOS F160W and F222M images. The sensitivity of the survey varies significantly with position, reaching a limiting depth of AB(1.6{mu}m)~28.7 and covering 1.01arcmin^2^ to AB(1.6{mu}m)=27 and 1.05arcmin^2^ to AB(1.6{mu}m)=26.5. The catalog of photometric redshifts identifies 21 galaxies (or 6% of the total) of redshift z>5, eight galaxies (or 2% of the total) of redshift z>10, and 11 galaxies (or 3% of the total) of best-fit spectral type E/S0, of which five galaxies (or 1% of the total) are of redshift z>1.
- ID:
- ivo://CDS.VizieR/J/AJ/120/2747
- Title:
- HDF-South WFPC2 observations
- Short Name:
- J/AJ/120/2747
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Hubble Deep Field South (HDF-S) observations targeted a high Galactic latitude field near QSO J2233-606. We present Wide Field Planetary Camera 2 observations of the field in four wide bandpasses centered at roughly 300, 450, 606, and 814 nm. Observations, data reduction procedures, and noise properties of the final images are discussed in detail. A catalog of sources is presented, and the number counts and color distributions of the galaxies are compared with a new catalog of the original Hubble Deep Field (HDF-N) that has been constructed in an identical manner. The two fields are qualitatively similar, with the galaxy number counts for the two fields agreeing to within 20%. The HDF-S has more candidate Lyman break galaxies at z>2 than the HDF-N. The star formation rate per unit volume computed from the HDF-S, based on the UV luminosity of high-redshift candidates, is a factor of 1.9 higher than from the HDF-N at z~2.7, and a factor of 1.3 higher at z~4.
- ID:
- ivo://CDS.VizieR/J/AJ/119/486
- Title:
- HDF-S: STIS imaging
- Short Name:
- J/AJ/119/486
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the imaging observations made with the Space Telescope Imaging Spectrograph (STIS) of the Hubble Deep Field South. The field was imaged in four bandpasses: a clear CCD bandpass for 156ks, a long-pass filter for 22-25ks/pix typical exposure, a near-UV bandpass for 23ks, and a far-UV bandpass for 52ks. The clear, visible image is the deepest observation ever made in the UV-optical wavelength region, reaching a 10{sigma}AB magnitude of 29.4 for an object of area 0.2arcsec^2^. The field contains QSO J2233-606, the target of the STIS spectroscopy, and extends 50"x50" for the visible images, and 25"x25" for the ultraviolet images. We present the images, catalog of objects, and galaxy counts obtained in the field.
- ID:
- ivo://CDS.VizieR/J/ApJS/166/549
- Title:
- HST/ACS observations of NGC 346
- Short Name:
- J/ApJS/166/549
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a photometric study of the star-forming region NGC 346 and its surrounding field in the Small Magellanic Cloud, using data taken with the Advanced Camera for Surveys (ACS) on board the Hubble Space Telescope (HST). The data set contains both short and long exposures for increased dynamic range, and photometry was performed using the ACS module of the stellar photometry package DOLPHOT. We detected almost 100,000 stars over a magnitude range of V~11 to V~28 mag, including all stellar types from the most massive young stars to faint lower main-sequence and pre-main-sequence stars. We find that this region, which is characterized by a plethora of stellar systems and interesting objects, is an outstanding example of mixed stellar populations. We take into account different features of the color-magnitude diagram of all the detected stars to distinguish the two dominant stellar systems: the stellar association NGC 346 and the old spherical star cluster BS 90. These observations provide a complete stellar sample of a field about 5'x5' around the most active star-forming region in this galaxy. Considering the importance of these data for various investigations in the area, we provide the full stellar catalog from our photometry. This paper is the first part of an ongoing study to investigate in detail the two dominant stellar systems in the area and their surrounding field.
- ID:
- ivo://CDS.VizieR/B/hst
- Title:
- HST Archived Exposures Catalog
- Short Name:
- B/hst
- Date:
- 20 Feb 2022 06:00:52
- Publisher:
- CDS
- Description:
- This catalogue is a copy of the Archived Exposures Catalog (AEC) compiled from the Hubble Space Telescope Data Archive database, with an indication about the existence of scientific images or spectra. It provides a summary of completed HST science observations. This catalogue contains also WFPC2 observations stacked into associations which usage is recommended for a large fraction of the WFPC2 images (see details in the "WFPC2 Associations" section below).
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