- ID:
- ivo://CDS.VizieR/J/ApJ/613/200
- Title:
- Hubble Higher z Supernova Search, HHZSS
- Short Name:
- J/ApJ/613/200
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results from the Hubble Higher z Supernova Search, the first space-based open field survey for supernovae (SNe). In cooperation with the Great Observatories Origins Deep Survey, we have used the Hubble Space Telescope with the Advanced Camera for Surveys to cover ~300arcmin^2^ in the area of the Chandra Deep Field South and the Hubble Deep Field North on five separate search epochs (separated by ~45day intervals) to a limiting magnitude of F850LP~26. These deep observations have allowed us to discover 42 SNe in the redshift range 0.2<z<1.6. As these data span a large range in redshift, they are ideal for testing the validity of Type Ia supernova progenitor models with the distribution of expected "delay times" from progenitor star formation to Type Ia SN explosion, and the SN rates these models predict. Through a Bayesian maximum likelihood test, we determine which delay-time models best reproduce the redshift distribution of SNe Ia discovered in this survey. We find that models that require a large fraction of "prompt" (less than 2Gyr) SNe Ia poorly reproduce the observed redshift distribution and are rejected at greater than 95% confidence. We find that Gaussian models best fit the observed data for mean delay times in the range of 2-4Gyr.
Number of results to display per page
Search Results
- ID:
- ivo://CDS.VizieR/II/342
- Title:
- Hubble Source Catalog (V1 and V2)
- Short Name:
- II/342
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Hubble Source Catalog is designed to help optimize science from the Hubble Space Telescope (HST) by combining the tens of thousands of visit-based source lists in the Hubble Legacy Archive (HLA) into a single master catalog. Version 1 of the Hubble Source Catalog includes WFPC2, ACS/WFC, WFC3/UVIS, and WFC3/IR photometric data generated using SExtractor software to produce the individual source lists. The catalog includes roughly 80 million detections of 30 million objects involving 112 different detector/filter combinations, and about 160,000 HST exposures. Source lists from Data Release 8 of the HLA are matched using an algorithm developed by Budavari & Lubow (2012ApJ...761..188B). The mean photometric accuracy for the catalog as a whole is better than 0.10mag, with relative accuracy as good as 0.02mag in certain circumstances (e.g., bright isolated stars). The relative astrometric residuals are typically within 10mas, with a value for the mode (i.e., most common value) of 2.3mas. The absolute astrometric accuracy is better than 0.1" for most sources, but can be much larger for a fraction of fields that could not be matched to the PanSTARRS, SDSS, or 2MASS reference systems. In this paper we describe the database design with emphasis on those aspects that enable the users to fully exploit the catalog while avoiding common misunderstandings and potential pitfalls. We provide usage examples to illustrate some of the science capabilities and data quality characteristics, and briefly discuss plans for future improvements to the Hubble Source Catalog.
- ID:
- ivo://CDS.VizieR/J/MNRAS/413/80
- Title:
- Hubble Space Telescope GOODS NICMOS Survey
- Short Name:
- J/MNRAS/413/80
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the details and early results from a deep near-infrared survey utilizing the NICMOS instrument on the Hubble Space Telescope centred around massive M*>10^11^M_{sun}_ galaxies at 1.7<z<2.9 found within the Great Observatories Origins Deep Survey (GOODS) fields North and South. The GOODS NICMOS Survey (GNS) was designed to obtain deep F160W (H-band) imaging of 80 of these massive galaxies and other colour-selected objects such as Lyman-break dropouts, BzK objects, distant red galaxies (DRGs), extremely red objects (EROs), Spitzer-selected EROs, BX/BM galaxies, as well as flux-selected submillimetre galaxies. We present in this paper details of the observations, our sample selection, as well as a description of the properties of the massive galaxies found within our survey fields. This includes photometric redshifts, rest-frame colours and stellar masses. We furthermore provide an analysis of the selection methods for finding massive galaxies at high redshifts, including colour-selection methods and how galaxy populations selected through these colour methods overlap.
- ID:
- ivo://CDS.VizieR/J/ApJS/222/11
- Title:
- Hubble Tarantula Treasury Project (HTTP). III.
- Short Name:
- J/ApJS/222/11
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present and describe the astro-photometric catalog of more than 800000 sources found in the Hubble Tarantula Treasury Project (HTTP). HTTP is a Hubble Space Telescope Treasury program designed to image the entire 30 Doradus region down to the sub-solar (~0.5M_{sun}_) mass regime using the Wide Field Camera 3 and the Advanced Camera for Surveys. We observed 30 Doradus in the near-ultraviolet (F275W, F336W), optical (F555W, F658N, F775W), and near-infrared (F110W, F160W) wavelengths. The stellar photometry was measured using point-spread function fitting across all bands simultaneously. The relative astrometric accuracy of the catalog is 0.4mas. The astro-photometric catalog, results from artificial star experiments, and the mosaics for all the filters are available for download. Color-magnitude diagrams are presented showing the spatial distributions and ages of stars within 30 Dor as well as in the surrounding fields. HTTP provides the first rich and statistically significant sample of intermediate- and low-mass pre-main sequence candidates and allows us to trace how star formation has been developing through the region. The depth and high spatial resolution of our analysis highlight the dual role of stellar feedback in quenching and triggering star formation on the giant HII region scale. Our results are consistent with stellar sub-clustering in a partially filled gaseous nebula that is offset toward our side of the Large Magellanic Cloud.
- ID:
- ivo://CDS.VizieR/J/AJ/132/1729
- Title:
- Hubble Ultra Deep Field BVI-dropout sources
- Short Name:
- J/AJ/132/1729
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper presents the Hubble Ultra Deep Field (HUDF), a 1 million secs exposure of an 11arcmin^2^ region in the southern sky with the Advanced Camera for Surveys on the Hubble Space Telescope using Director's Discretionary Time. The exposure time was divided among four filters, F435W (B435), F606W (V606), F775W (i775), and F850LP (z850), to give approximately uniform limiting magnitudes m_AB_~29 for point sources. The image contains at least 10000 objects, presented here as a catalog, the vast majority of which are galaxies. Visual inspection of the images shows few if any galaxies at redshifts greater than ~4 that resemble present-day spiral or elliptical galaxies. The image reinforces the conclusion from the original Hubble Deep Field that galaxies evolved strongly during the first few billion years in the infancy of the universe. Using the Lyman break dropout method to derive samples of galaxies at redshifts between 4 and 7, it is possible to study the apparent evolution of the galaxy luminosity function and number density.
- ID:
- ivo://CDS.VizieR/II/258
- Title:
- Hubble Ultra Deep Field Catalog (UDF)
- Short Name:
- II/258
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Hubble Ultra Deep Field (PI: Steven V. W. Beckwith) is a 400-orbit Cycle 12 program to image a single field of the Wide Field Camera (WFC) of the Advanced Camera for Surveys (ACS) in four filters: F435W (B), F606W (V), F775W (i), and F850LP (z). The observations took place over 4 months from September 2003 to January 2004 under two program IDs: 9978 and 10086. The observations consist of half-orbit exposures, cycling through each of the filters in a 4-point dither pattern to provide sub-pixel sampling, as well as a larger-scale 3-point line pattern to cover the 2 second of arc gap between the two ACS/WFC chips. The total exposure times are summarized below, with typical exposure times of 1200s for individual images. The AB magnitude zero-points for ACS are current as of March 2004. --------------------------------------------------------------- Number of Number of Total Exp. AB mag. Orbits Exposures Time (s) zero-point --------------------------------------------------------------- B (F435W): 56 112 134880 25.673 V (F606W): 56 112 135320 26.486 i (F775W): 144 288 347110 25.654 z (F850LP): 144 288 346620 24.862 --------------------------------------------------------------- More details are found in the "intro.txt" file, or from the UDF home page.
- ID:
- ivo://CDS.VizieR/J/ApJ/606/L25
- Title:
- Hubble Ultra Deep Parallel Fields
- Short Name:
- J/ApJ/606/L25
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report on the i-dropouts detected in two exceptionally deep Advanced Camera for Surveys fields (B_435_, V_606_, i_775_, and z_850_ with 10{sigma} limits of 28.8, 29.0, 28.5, and 27.8, respectively) taken in parallel with the Ultra Deep Field Near-Infrared Camera and Multi-Object Spectrometer observations. Using an i-z>1.4 cut, we find 30 i-dropouts over 21-arcmin^2^ down to z_(850,AB)_=28.1, or 1.4 i-dropouts arcmin^-2^, with significant field-to-field variation (as expected from cosmic variance). This extends i-dropout searches some ~0.9mag further down the luminosity function than was possible in the Great Observatories Origins Deep Survey (GOODS) fields, yielding a ~7 times increase in surface density. An estimate of the size evolution for UV-bright objects is obtained by comparing the composite radial flux profile of the bright i-dropouts (z_(850,AB)_<27.2) with scaled versions of the Hubble Deep Field North and South U-dropouts.
- ID:
- ivo://CDS.VizieR/J/ApJ/735/L22
- Title:
- HUDF galaxy properties at z~2
- Short Name:
- J/ApJ/735/L22
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use ultra-deep Hubble Space Telescope Wide Field Camera 3/infrared imaging of the Hubble Ultra Deep Field to investigate the rest-frame optical morphologies of a mass-selected sample of galaxies at z~2. We find a large variety of galaxy morphologies, ranging from large, blue, disk-like galaxies to compact, red, early-type galaxies. We derive rest-frame u-g color profiles for these galaxies and show that most z~2 galaxies in our sample have negative color gradients such that their cores are red.
- ID:
- ivo://CDS.VizieR/J/A+A/635/A66
- Title:
- Humps and bumps in RR Lyrae stars
- Short Name:
- J/A+A/635/A66
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the most extended and homogeneous study carried out so far of the main and early shocks in 1485 RR Lyrae stars in the Galactic bulge observed by the Optical Gravitational Lensing Experiment (OGLE). We selected nonmodulated fundamental-mode RR Lyrae stars with good-quality photometry. Using a self- developed method, we determined the centers and strengths of main and early shock features in the phased light curves. We found that the positions of both humps and bumps are highly correlated with the pulsation properties of the studied variables. Pulsators with a pronounced main shock are concentrated in the low-amplitude regime of the period-amplitude diagram, while stars with a strong early shock have average and above-average pulsation amplitudes. A connection between the main and early shocks and the Fourier coefficients is also observed. In the color-magnitude diagram (CMD), we see a separation between stars with strong and weak shocks. Variables with a pronounced main shock cluster close to the fundamental red edge of the instability strip (IS), while stars with a strong early shock tend to clump in the center and near the fundamental blue edge of the IS. The appearance of shocks and their properties appear to be independent of the direction of evolution estimated from the period change rate of the studied stars. In addition, the differences in the period change rate between the two main Oosterhoff groups found in the Galactic bulge suggest that stars of Oosterhoff type I are located close to the zero-age horizontal branch while Oosterhoff type II variables are on their way toward the fundamental red edge of the instability strip, and have therefore already left the zero-age horizontal branch.
- ID:
- ivo://CDS.VizieR/J/A+A/592/A117
- Title:
- HU Vir radial velocities and VI light curves
- Short Name:
- J/A+A/592/A117
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate the differential surface rotation on the primary star of the RS CVn binary HU Vir by tracking its starspot distribution as a function of time. We also recompute and update the values for several system parameters of the triple system HU Vir (close and wide orbits). Spectroscopic observations were carried out with the STELLA echelle spectrograph (SES) at the robotic 1.2-m STELLA-I telescope at the Observatorio del Teide in Tenerife, Spain. A time series of 118 echelle spectra was taken in the period between Feb 17 to Jun 26, 2013. Nine consecutive Doppler images were reconstructed from these data, using our line-profile inversion code iMap. An image cross-correlation method was applied to derive the surface differential-rotation law for HU Vir. New orbital elements for the close and the wide orbits were computed using our new STELLA RVs combined with the RV data available in the literature. Photometric observations were performed with the Amadeus Automatic Photoelectric Telescope (APT) at Fairborn Observatory in southern Arizona starting in 1996, providing contemporaneous Johnson-Cousins V and I data for approximately 20 years. This data was used to determine the stellar rotation period and the active longitudes.
