The ACS Survey of Galactic Globular Clusters. I. Overview and Clusters without Previous<i>Hubble Space Telescope</i>Photometry

Sarajedini, Ata; Bedin, L. R.; Chaboyer, Brian; Dotter, Aaron; Siegel, M. H.; Anderson, Jay; Aparicio, A.; King, Ivan R.; Majewski, Steven R.; Marín-Franch, A.; Piotto, G.; Reid, I. Neill; Rosenberg, Alfred

doi:10.1086/511979

Cited by 503 publications

(749 citation statements)

References 48 publications

Supporting

Mentioning

720

Contrasting

Unclassified

Order By: Relevance

“…We then used a software program that is similar to that developed by Anderson et al (2008) for the ACS Survey of Galactic Globular Clusters (GO-10775, Sarajedini et al 2007) treasury project to go through the field in 120×120-pixel tiles to iteratively find and measure stars simultaneously in all 50 contributing WFC3/UVIS/F467M 390 s exposures. Figure 7 shows the depth of coverage for the WFC3/UVIS observations, an image of the field, and a close-up of a representative 20 ×20 region.…”

Section: Wfc3/uvismentioning

confidence: 99%

“…Field-objects mainly belong to the outskirts of the Galactic Bulge, which is in the background of M 4. To demonstrate this PM separation, we downloaded from HST's archive images collected under program GO-10775 (PI: Sarajedini) on 2006 May 3 (Sarajedini et al 2007), and use them as a previous epoch. We reduced flc ACS/WFC images in filters F606W and F814W, 4 per filter of 25-30 s, and extracted fluxes and positions.…”

Section: Preliminary Astrometric Precisionmentioning

confidence: 99%

See 1 more Smart Citation

The M 4 Core Project with HST: I. Overview and first epoch

et al. 2013

View full text Add to dashboard Cite

We present an overview of the ongoing Hubble Space Telescope large program GO-12911. The program is focused on the core of M 4, the nearest Galactic globular cluster, and the observations are designed to constrain the number of binaries with massive companions (black holes, neutron stars, or white dwarfs) by measuring the "wobble" of the luminous (mainsequence) companion around the center of mass of the pair, with an astrometric precision of ∼ 50 μas. The high spatial resolution and stable medium-band PSFs of WFC3/UVIS will make these measurements possible. In this work we describe (i) the motivation behind this study, (ii) our observing strategy, (iii) the many other investigations enabled by this unique data set, and which of those our team is conducting, and (iv) a preliminary reduction of the first-epoch dataset collected on

show abstract

Section: Wfc3/uvismentioning

confidence: 99%

Section: Preliminary Astrometric Precisionmentioning

confidence: 99%

The M 4 Core Project with HST: I. Overview and first epoch

et al. 2013

View full text Add to dashboard Cite

show abstract

“…But in any case, a proper radial-distribution analysis needs correction even for a differential reddening that is of the order of few hundredths of a magnitude. Our corrections for differential reddening followed the method outlined by Sarajedini et al (2007), which uses the displacements of individual stars from a fiducial sequence to derive a reddening map.…”

Section: The Astrometric and Photometric Reference Framementioning

confidence: 99%

Radial distribution of the multiple stellar populations in $\mathsf{\omega}$ Centauri

Bellini

Piotto

Bedin

et al. 2009

A&A

115

109

View full text Add to dashboard Cite

Aims. We present a detailed study of the radial distribution of the multiple populations identified in the Galactic globular cluster ω Cen. Methods. We used both space-based images (ACS/WFC and WFPC2) and ground-based images (FORS1@VLT and WFI@2.2m ESO telescopes) to map the cluster from the inner core to the outskirts (∼20 arcmin). These data sets have been used to extract high-accuracy photometry for the construction of color−magnitude diagrams and astrometric positions of ∼900 000 stars. Results. We find that in the inner ∼2 core radii the blue main sequence (bMS) stars slightly dominate the red main sequence (rMS) in number. At greater distances from the cluster center, the relative numbers of bMS stars with respect to rMS drop steeply, out to ∼8 arcmin, and then remain constant out to the limit of our observations. We also find that the dispersion of the Gaussian that best fits the color distribution within the bMS is significantly greater than the dispersion of the Gaussian that best fits the color distribution within the rMS. In addition, the relative number of intermediate-metallicity red-giant-branch stars (which includes the progeny of the bMS) with respect to the metal-poor component (the progeny of the rMS) follows a trend similar to that of the main-sequence star-count ratio N bMS /N rMS . The most metal-rich component of the red-giant branch follows the same distribution as the intermediatemetallicity component. Conclusions. We briefly discuss the possible implications of the observed radial distribution of the different stellar components in ω Cen.

show abstract

“…We used the photometry catalogue provided via the "ACS Survey of Galactic Globular Clusters" web-page. The data and data reduction are described in detail in Sarajedini et al (2007) and Anderson et al (2008).…”

Section: Optical Catalogmentioning

confidence: 99%

“…The other two sources are most likely bright and blue BSs, but could also be fainter (and slightly redder) extreme blue HB (EHB) Figure 3. Optical CMD of NGC 6397, data taken from the ACS Survey of Galactic Globular Clusters (Sarajedini et al 2007). The symbols are the same as in Fig.…”

Section: Optical Cmdmentioning

confidence: 99%

Far-ultraviolet observation of the globular cluster NGC 6397

Dieball

Rasekh

Knigge

et al. 2017

Monthly Notices of the Royal Astronomical Society

View full text Add to dashboard Cite

We present an observational far-UV (FUV) and near-UV (NUV) study of the core region of the globular cluster NGC 6397. The observations were obtained with the Space Telescope Imaging Spectrograph (STIS, FUV), and the Wide Field Camera 3 (WFC3, NUV) on board the Hubble Space Telescope. Here, we focus on the UV bright stellar populations such as blue stragglers (BSs), white dwarfs (WDs) and cataclysmic variables (CVs). We present the first FUV − NUV color-magnitude diagram (CMD) for this cluster. To support our classification of the stellar populations, we compare our FUV − NUV CMD with optical data from the ACS Survey of Galactic Globular Clusters. The FUV − NUV CMD indicates 16 sources located in the WD area, and ten BSs within the 25 ′′ × 25 ′′ of the STIS FUV data. Eighteen Chandra X-ray sources are located within the FUV field of view. Thirteen of those have a NUV counterpart, of which nine sources also have a FUV counterpart. Out of those, five sources are previously suggested CVs, and indeed all five are located in the WD/CV region in our FUV − NUV CMD. Another CV only has a FUV but no NUV counterpart. We also detect a NUV (but no FUV) counterpart to the MSP located in the core of this cluster. The NUV lightcurves of the CVs and MSP show flickering behaviour typical of CVs. We found that the BSs and CVs are the most centrally concentrated population. This might be an effect of mass segregation or indicate the preferred birth place of BSs and CVs via dynamical interactions in the dense core region of GCs. HB stars are the least centrally concentrated population and absent in the innermost area of the core.

show abstract

The ACS Survey of Galactic Globular Clusters. I. Overview and Clusters without PreviousHubble Space TelescopePhotometry

Cited by 503 publications

References 48 publications

The M 4 Core Project with HST: I. Overview and first epoch

The M 4 Core Project with HST: I. Overview and first epoch

Radial distribution of the multiple stellar populations in $\mathsf{\omega}$ Centauri

Far-ultraviolet observation of the globular cluster NGC 6397

Contact Info

Product

Resources

About