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1. A103, A118 and A114 morphological studies
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).
2. ACS Galactic Globular Cluster Survey (ACSGGCT)
ID:
ivo://mast.stsci/acsggct
Title:
ACS Galactic Globular Cluster Survey (ACSGGCT)
Short Name:
HST.ACSGGCT
Date:
22 Jul 2020 22:26:50
Publisher:
Space Telescope Science Institute Archive
Description:
The ACSGGCT program used the HST ACS/WFC instrument to obtain uniform imaging of 65 of the nearest globular clusters to provide an extensive homogeneous dataset for a broad range of scientific investigations. An overview of the project was published by Sarajedini, A. et al. 2007, "The ACS Survey of Galactic Globular Clusters. I. Overview and Clusters Without Previous Hubble Space Telescope Photometry" AJ, 133, 1658.
3. Advanced Camera for Surveys
ID:
ivo://archive.stsci.edu/hst/acs
Title:
Advanced Camera for Surveys
Short Name:
HST.ACS
Date:
23 Jul 2020 19:47:47
Publisher:
Space Telescope Science Institute Archive
Description:
HST Advanced Camera for Surveys (ACS) - Images: CCD images between 3,700 - 11
4. Ages for globular clusters in the halo
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.
5. Archive of Nearby Galaxies: Reduce, Reuse, Recycle (ANGRRR)
ID:
ivo://mast.stsci/angrrr
Title:
Archive of Nearby Galaxies: Reduce, Reuse, Recycle (ANGRRR)
Short Name:
HST.ANGRRR
Date:
22 Jul 2020 22:28:43
Publisher:
Space Telescope Science Institute Archive
Description:
An archive of stellar photometry for galaxies within 3.5 Mpc, excluding Local Group galaxies, based on primary and parallel wide-filter UV and optical observations taken with HST ACS/WFC or WFPC2.The sample includes all observations taken through Dec. 2008, as well as observations taken as part of Cycle 16 Supplemental GO programs 11986 and 11987. This release includes the ANGST targets within 3.5 Mpc; these observations have been rereduced using updated CTE corrections and zeropoints. Galaxies with 3.5 < D <= 5 Mpc will be included in a later release.
6. Blue stragglers in M3
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.
7. Brightest of Reionizing Galaxies (BoRG)
ID:
ivo://archive.stsci.edu/borg
Title:
Brightest of Reionizing Galaxies (BoRG)
Short Name:
BoRG
Date:
22 Jul 2020 22:24:07
Publisher:
Space Telescope Science Institute Archive
Description:
The Brightest of Reionizing Galaxies (BoRG) observations were first obtained in HST Cycle 17 in program GO 11700 (PI: Michele Trenti). BoRG is an ongoing pure-parallel program that obtains WFC3 imaging in four filters (F606W, F098M, F125W, F160W) on random sightlines at high Galactic latitudes (|b| > 30 degrees). BoRG also assimilates data from the similar Hubble Infrared Pure Parallel Imaging Extragalactic Survey (HIPPIES) pure-parallel program (GO 11702; PI: Yan). Data from the HIPPIES program uses the F600LP filter instead of F606W.
8. Cepheid calibration of SN 1989B in NGC 3627
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.
9. Cluster Lensing And Supernova survey with Hubble (CLASH)
ID:
ivo://mast.stsci/clash
Title:
Cluster Lensing And Supernova survey with Hubble (CLASH)
Short Name:
HST.CLASH
Date:
22 Jul 2020 22:29:29
Publisher:
Space Telescope Science Institute Archive
Description:
By observing 25 massive galaxy clusters with HST's new panchromatic imaging capabilities (Wide-field Camera 3, WFC3, and the Advanced Camera for Surveys, ACS), CLASH will accomplish its four primary science goals: - Map, with unprecedented accuracy, the distribution of dark matter in galaxy clusters using strong and weak gravitational lensing; - Detect Type Ia supernovae out to redshift z ~ 2, allowing us to test the constancy of dark energy's repulsive force over time and look for any evolutionary effects in the supernovae themselves; - Detect and characterize some of the most distant galaxies yet discovered at z > 7 (when the Universe was younger than 800 million years old - or less than 6% of its current age); - Study the internal structure and evolution of the galaxies in and behind these clusters.
10. Composite HST Spectrum of Quasars
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.