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21. HST observations of carbon in spiral galaxies
ID:
ivo://CDS.VizieR/J/ApJ/513/168
Title:
HST observations of carbon in spiral galaxies
Short Name:
J/ApJ/513/168
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present measurements of the gas-phase abundance ratio C/O in six H II regions in the spiral galaxies M101 and NGC 2403, based on ultraviolet spectroscopy using the Faint Object Spectrograph on the Hubble Space Telescope. The ratios of C to O increase systematically with O/H in both galaxies, from log(C/O){~=}-0.8 at log(O/H){~=}-4.0 to log(C/O){~=}-0.1 at log(O/H){~=}-3.4. C/N shows no correlation with O/H. The rate of increase of C/O is somewhat uncertain because of uncertainty as to the appropriate UV reddening law and uncertainty in the metallicity dependence on grain depletions. However, the trend of increasing C/O with O/H is clear, confirming and extending the trend in C/O indicated previously from observations of irregular galaxies. Our data indicate that the radial gradients in C/H across spiral galaxies are steeper than the gradients in O/H. Comparing the data to chemical-evolution models for spiral galaxies shows that models in which the massive star yields do not vary with metallicity predict radial C/O gradients that are much flatter than the observed gradients.
22. HST photometry of 4 Virgo LSB galaxies
ID:
ivo://CDS.VizieR/J/ApJS/128/99
Title:
HST photometry of 4 Virgo LSB galaxies
Short Name:
J/ApJS/128/99
Date:
21 Oct 2021
Publisher:
CDS
Description:
Utilizing the F814W and F300W filters, Hubble Space Telescope Wide Field Planetary Camera-2 (WFPC2) images were taken of four low surface brightness galaxies in the direction of the Virgo Cluster - V7L3, V2L8, V1L4, and Malin 1. The high resolution of the WFPC2 combined with the extremely diffuse nature of the four galaxies makes them essentially transparent, allowing for the serendipitous discovery of 139 background galaxies visible through both the disks and nuclei of the foreground galaxies. Surface photometry was done on the newly discovered galaxies through the F814W (I-band) filter. The detected galaxies have both r1/4 and exponential-type profiles with radii (to the {mu}_F814W_=25.0mag/arcsec^2^ limit) less than 5.0". Their total magnitudes range from 18.9 through the survey cutoff at 25.0 in the F814W filter.
23. HST snapshot survey of 3CR radio sources
ID:
ivo://CDS.VizieR/J/ApJS/122/81
Title:
HST snapshot survey of 3CR radio sources
Short Name:
J/ApJS/122/81
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present and describe optical counterparts to 46 3CR radio galaxies of redshifts less than 0.1 that were imaged with the Hubble Space Telescope's (HST) WFPC2 camera through the broadband F702W filter as part of the 3CR Snapshot Survey. This is the fifth and last such paper describing the 252 radio galaxies of this R-band survey. At the 0.1'' resolution of the images, a wealth of detail is visible. Approximately 89% of the galaxies are ellipticals, and nearly all reside in groups or clusters of galaxies of various richness and compactness. Nearby elliptical companions of slightly smaller size and mass are common. Dust is prevalent in the cores of the 3C hosts; nearly half of the galaxies possess some type of dust structure, such as irregular dust lanes, filaments, or disks. Besides the well-known dust disks of 3C 264 and 3C 270, we have found five new candidates in 3C 31, 3C 40, 3C 296, 3C 449, and 3C 465, as well as in the central regions of the nearby neighbors of 3C 31 and 3C 465. Our sample includes six confirmed optical synchrotron jets in 3C 15, 3C 66B, 3C 78, 3C 264, 3C 274, and 3C 371, or approximately 13% of the sample. Unresolved nuclei, consistent with the point spread function of WFPC2, are found in 43%-54% of the galaxies and in the majority of galaxies with dust disks and optical jets.
24. HST Space Telescope Imaging Spectrograph
ID:
ivo://mast.stsci/ssap/hst/stis
Title:
HST Space Telescope Imaging Spectrograph
Short Name:
HST STIS Spectra
Date:
22 Jul 2020 21:58:09
Publisher:
Space Telescope Science Institute Archive
Description:
MAST-produced spectral container files for STIS spectra. STIS spectra range from 1150 to 10,300 at low to medium spectral resolution, high spatial resolution echelle spectroscopy in the ultraviolet. STIS began operation in 1997. (Note the included echelle spectra are technically not yet supported by the SSAP.)
25. HST studies of the WLM globular cluster
ID:
ivo://CDS.VizieR/J/ApJ/521/577
Title:
HST studies of the WLM globular cluster
Short Name:
J/ApJ/521/577
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have obtained V and I images of the lone globular cluster that belongs to the dwarf Local Group irregular galaxy known as WLM. The color-magnitude diagram of the cluster shows that it is a normal old globular cluster with a well-defined giant branch reaching to M_V_=-2.5, a horizontal branch at M_V_=+0.5, and a subgiant branch extending to our photometry limit of M_V_=+2.0. A best fit to theoretical isochrones indicates that this cluster has a metallicity of [Fe/H]=-1.52{+/-}0.08 and an age of 14.8{+/-}0.6 Gyr, thus indicating that it is similar to normal old halo globulars in our Galaxy. From the fit we also find that the distance modulus of the cluster is 24.73{+/-}0.07 and the extinction is A_V_=0.07{+/-}0.06, both values that agree within the errors with data obtained for the galaxy itself by others.
26. Hubble Deep Field catalog of color-based redshift
ID:
ivo://CDS.VizieR/J/AJ/116/2081
Title:
Hubble Deep Field catalog of color-based redshift
Short Name:
J/AJ/116/2081
Date:
21 Oct 2021
Publisher:
CDS
Description:
We derive simple empirical color-redshift relations for z<~4 galaxies in the Hubble Deep Field (HDF) using a linear function of three photometric colors (U-B, B-V, V-I). The dispersion between the estimated redshifts and the spectroscopically observed ones is small for relations derived in several separate color regimes; the dispersions range from {sigma}_z_~=0.03 to 0.1 for z<~2 galaxies, and from {sigma}_z_~=0.14 to 0.25 for z>~2 galaxies. We apply the color-redshift relations to the HDF photometric catalog and obtain estimated redshifts that are consistent with those derived from spectral template fitting methods. The advantage of these color-redshift relations is that they are simple and easy to use and do not depend on the assumption of any particular spectral templates; they provide model independent redshift estimates for z<~4 galaxies using only multiband photometry, and they apply to about 90% of all galaxies. We provide a color-based estimated redshift catalog of HDF galaxies to z<~4. We use the estimated redshifts to investigate the redshift distribution of galaxies in the HDF; we find peaks in the redshift distribution that suggest large-scale clustering of galaxies to at least z~1 and that are consistent with those identified in spectroscopic probes of the HDF.
27. Hubble Deep Field near-IR obs.
ID:
ivo://CDS.VizieR/J/AJ/117/17
Title:
Hubble Deep Field near-IR obs.
Short Name:
J/AJ/117/17
Date:
21 Oct 2021
Publisher:
CDS
Description:
This paper presents data obtained during the NICMOS Guaranteed Time Observations of a portion of the Hubble Deep Field. The data are in a catalog format similar to the publication of the original WFPC2 Hubble Deep Field program (Williams et al., 1996, Cat. <J/AJ/112/1335>). The catalog contains 342 objects in a 49.1"x48.4" subfield of the total observed field, 235 of which are considered coincident with objects in the WFPC2 catalog. The 3{sigma} signal-to-noise ratio level is at an aperture AB magnitude of approximately 28.8 at 1.6{mu}m. The catalog sources, listed in order of right ascension, are selected to satisfy a limiting signal-to-noise ratio criterion of greater than or equal to 2.5. This introduces a few false detections into the catalog, and users should take careful note of the completeness and reliability levels for the catalog discussed in sections 9 and 10. The catalog also contains a test parameter indicating the results of half-catalog tests and the degree of coincidence with the original WFPC2 catalog.
28. Hubble Deep Field observations
ID:
ivo://CDS.VizieR/J/AJ/112/1335
Title:
Hubble Deep Field observations
Short Name:
J/AJ/112/1335
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Hubble Deep Field (HDF) is a Director's Discretionary program on HST in Cycle 5 to image an undistinguished field at high Galactic latitude in four passbands as deeply as reasonably possible. These images provide the most detailed view to date of distant field galaxies and are likely to be important for a wide range of studies in galaxy evolution and cosmology. In order to optimize observing in the time available, a field in the northern continuous viewing zone was selected and images were taken for ten consecutive days, or approximately 150 orbits. Shorter 1-2 orbit images were obtained of the fields immediately adjacent to the primary HDF in order to facilitate spectroscopic follow-up by ground- based telescopes. The observations were made from 1995 December 18-30, and both raw and reduced data have been put in the public domain as a community service. We present a summary of the criteria for selecting the field, the rationale behind the filter selection and observing times in each band, and the strategies for planning the observations to maximize the exposure time while avoiding Earth-scattered light. Data reduction procedures are outlined, and images of the combined frames in each band are presented. Objects detected in these images are listed in a catalog with their basic photometric parameters.
29. Hubble Deep Field surface photometry
ID:
ivo://CDS.VizieR/J/A+AS/129/583
Title:
Hubble Deep Field surface photometry
Short Name:
J/A+AS/129/583
Date:
21 Oct 2021
Publisher:
CDS
Description:
The detailed surface photometry of a sample of early-type galaxies in the Hubble Deep Field is presented as part of a long-term project aimed to settle strong observational constraints to the theories modelling the evolution of elliptical galaxies from the early stages. The sample has been extracted, in the V_606_ band, from the database provided by the ESO-STECF-HDF Group (Couch, 1996, <http://ecf.hq.eso.org>). The selection criteria involve the total magnitude, the number of pixels detected above the background level and an automatic star/galaxy classifier. Moreover, form visual inspection of the frames, we excluded the galaxies showing unambiguous late-type morphology. The analysis of the luminosity and geometrical profiles, carried out on the 162 candidates obeying our selection criteria, resulted in a list of 99 'bona fide' early-type galaxies, for which accurate total magnitudes and effective radii were computed on the basis of the equivalent luminosity profiles. The comparison with the magnitudes given by Williams et al. (1996, Cat. <J/AJ/112/1335>) indicates that the automated photometry tends to underestimate the total luminosity of the ellipticals. The luminosity profiles of most of galaxies in our sample follow fairly well the de~Vaucouleurs law ('Normal' profiles). However, a relevant fraction of galaxies, even following the r^1/4^ law in the main body light distribution, exhibit in the inner region a flattening of the luminosity profile not attributable to the PSF (`Flat' profiles) or, in some cases, a complex (multi-nucleus) structure (`Merger' profiles). A statistically significant correlation is found between the shapes of the luminosity profiles and the ellipticity distribution. In particular, the average ellipticity of galaxies belonging to the `Flat' and `Merger' classes is significantly higher than that of the `Normal' galaxies. Finally, even taken into account the relevant uncertainty of the outer position angle profiles, the amount of isophotal twisting of HDF ellipticals turns out to be significantly larger with respect to that of the local samples.
30. Hubble Infrared Pure Parallel Imaging Extragalactic Survey (HIPPIES)
ID:
ivo://mast.stsci/hippies
Title:
Hubble Infrared Pure Parallel Imaging Extragalactic Survey (HIPPIES)
Short Name:
HST.HIPPIES
Date:
22 Jul 2020 22:31:09
Publisher:
Space Telescope Science Institute Archive
Description:
Hubble Infrared Pure Parallel Imaging Extragalactic Survey (HIPPIES) utilizes long-duration pure parallel visits (~> 3 orbits) of HST at high Galactic latitude (|b|>20o) to take deep, multi-band images in WFC3 (since Cycle 17) and in ACS (starting Cycle 18). It is unique in its large number of descrete fields along random sightlines, and thus is complementary to other surveys over contiguous fields but along limited sightlines.