- ID:
- ivo://CDS.VizieR/J/A+A/310/715
- Title:
- Tucana dwarf galaxy VI photometry
- Short Name:
- J/A+A/310/715
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present deep CCD photometry for the dwarf galaxy in Tucana (l=323, b=-47.4). The data indicate that the galaxy is dominated by an intermediate/old stellar population with metallicity similar to that of the galactic globular clusters NGC 6752 and NGC 7089 (M2) (we find [Fe/H]=~-1.56). The distance modulus we derived, (m-M)_V_=~24.72+/-0.2, makes clear that this galaxy belongs to the Local Gro up. Tucana is clearly different from other dwarf galaxies, such as Leo I (Lee et al., 1993AJ....106.1420L), or Phoenix (Ortolani and Gratton, 1988PASP..100.1405O), because there is no evidence of a young stellar population (t<=5Gyrs) We suggest that the Tucana Galaxy is a genuine dwarf spheroidal in which no recent burst of star formation occurred.
Number of results to display per page
Search Results
- ID:
- ivo://nasa.heasarc/gc47tuccxo
- Title:
- 47 Tuc Globular Cluster Chandra X-Ray Point Source Catalog (2005 Version)
- Short Name:
- GC47TUCCXO
- Date:
- 28 Feb 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The authors have detected 300 X-ray sources within the half-mass radius (2.79') of the globular cluster 47 Tucanae in a deep (281 ks) Chandra exposure. They perform photometry and simple spectral fitting for our detected sources and construct luminosity functions, X-ray color-magnitude, and color-color diagrams. Eighty-seven X-ray sources show variability on timescales from hours to years. Thirty-one of the new X-ray sources are identified with chromospherically active binaries from the catalogs of Albrow and coworkers (2001, <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/ApJ/559/1060">CDS Catalog <J/ApJ/559/1060></a>). The authors estimate that the total number of neutron stars in 47 Tuc is of order 300, reducing the discrepancy between theoretical neutron star retention rates and observed neutron star populations in globular clusters. The data used in this paper are from the 2000 and 2002 Chandra observations of the globular cluster 47 Tuc. The 2000 observations, initially described in Grindlay et al. (2001, Science 292, 2290), were performed with the ACIS-I CCD array at the telescope focus, while the 2002 observations placed the back-illuminated ACIS-S aim point at the focus for maximum low-energy sensitivity. The authors combined the results from wavdetect source detection runs with a threshold probability of 1 x 10<sup>-5</sup>, in two energy bands (0.5 - 2.0 keV and 0.5 - 6.0 keV for the 2000 observations, and (0.3 - 2.0 keV and 0.3 - 6.0 keV for the 2002 observations), to make independent source lists for the 2000 and 2002 observations, given in Tables 2 and 3 of the reference paper, which have been combined in the present HEASARC table. A total of 146 sources were detected in this way in the 2000 observations (entries with dataset_year = 2000), while 300 sources were detected in the 2002 observations (dataset_year = 2002). A total of 143 of the sources were clearly detected in both observations, while only three of the sources from the 2000 observations were not detected in the 2002 observations. See also the related <a href="gc47tuccx2.html">2017 source catalog</a>. This table was created by the HEASARC in June 2007 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/ApJ/625/796">CDS Catalog J/ApJ/625/796</a> files table2.dat, table3.dat, and (part of) table5.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/gc47tuccx2
- Title:
- 47 Tuc Globular Cluster Chandra X-Ray Point Source Catalog (2017 Version)
- Short Name:
- GC47TUCCX2
- Date:
- 28 Feb 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The authors combined Chandra ACIS observations of the globular cluster 47 Tucanae (47 Tuc) from 2000, 2002, and 2014-2015 to create a deeper X-ray source list and study some of the faint radio millisecond pulsars (MSPs) present in this cluster. This work combined 180 ks of new Chandra ACIS data on 47 Tuc with 370 ks of archival data and used improved algorithms to generate a new source catalog, finding 81 new sources for a total of 370 within the half-mass region (2.79 arcsec) of the cluster. The majority of the newly identified sources are in the crowded core region, indicating cluster membership. The authors associated five of the new X-ray sources with chromospherically active BY Dra or W UMa variables identified by Albrow et al. (2001, <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/ApJ/559/1060">CDS Cat. <J/ApJ/559/1060></a>). See also the related <a href="gc47tuccxo.html">2005 source catalog</a>. This table was created by the HEASARC in September 2020 based upon the <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/MNRAS/472/3706">CDS Catalog J/MNRAS/472/3706</a> files table2.dat, table4.dat, and table5.dat. The optical names from Albrow et al. (2001) were subsequently corrected in October 2020 in order to use the recommendation from the CDS Dictionary of Nomenclature of Celestial Objects. This is a service provided by NASA HEASARC .
- ID:
- ivo://CDS.VizieR/J/AJ/127/1588
- Title:
- 47 Tuc main-sequence star abundances
- Short Name:
- J/AJ/127/1588
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the results of an analysis of CN and CH band strengths among a large sample of 47 Tucanae main-sequence and turnoff stars presented earlier by Harbeck et al. (2003, Cat. <J/AJ/125/197>).
- ID:
- ivo://CDS.VizieR/J/A+A/572/A108
- Title:
- 47 Tuc red giants chemical composition
- Short Name:
- J/A+A/572/A108
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The study of chemical abundance patterns in globular clusters is of key importance to constrain the different candidates for intra-cluster pollution of light elements. We aim at deriving accurate abundances for a large range of elements in the globular cluster 47 Tucanae (NGC 104) to add new constraints to the pollution scenarios for this particular cluster, expanding the range of previously derived element abundances. Using tailored 1D LTE atmospheric models together with a combination of equivalent width measurements, LTE, and NLTE synthesis we derive stellar parameters and element abundances from high-resolution, high signal-to-noise spectra of 13 red giant stars near the tip of the RGB. We derive abundances of a total 27 elements (O, Na, Mg, Al, Si, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Y, Zr, Mo, Ru, Ba, La, Ce, Pr, Nd, Eu, Dy). Departures from LTE were taken into account for Na, Al and Ba. We find a mean [Fe/H]=-0.78+/-0.07 and [alpha/Fe]=0.34+/-0.03 in good agreement with previous studies. The remaining elements show good agreement with the literature, but the inclusion of NLTE for Al has a significant impact on the behaviour of this key element. We confirm the presence of an Na-O anti-correlation in 47 Tucanae found by several other works. Our NLTE analysis of Al shifts the [Al/Fe] to lower values, indicating that this may be overestimated in earlier works. No evidence for an intrinsic variation is found in any of the remaining elements.
- ID:
- ivo://CDS.VizieR/J/MNRAS/459/610
- Title:
- 47 Tuc sub-giant branch chemical abundances
- Short Name:
- J/MNRAS/459/610
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The globular cluster 47 Tuc exhibits a complex sub-giant branch (SGB) with a faint-SGB comprising only about the 10 per cent of the cluster mass and a bright-SGB hosting at least two distinct populations. We present a spectroscopic analysis of 62 SGB stars including 21 faint-SGB stars. We thus provide the first chemical analysis of the intriguing faint-SGB population and compare its abundances with those of the dominant populations. We have inferred abundances of Fe, representative light elements C, N, Na, and Al, {alpha} elements Mg and Si for individual stars. Oxygen has been obtained by co-adding spectra of stars on different sequences. In addition, we have analysed 12 stars along the two main RGBs of 47 Tuc. Our principal results are (i) star-to-star variations in C/N/Na among RGB and bright-SGB stars; (ii) substantial N and Na enhancements for the minor population corresponding to the faint-SGB; (iii) no high enrichment in C+N+O for faint-SGB stars. Specifically, the C+N+O of the faint-SGB is a factor of 1.1 higher than the bright-SGB, which, considering random (+/-1.3) plus systematic errors (+/-0.3), means that their C+N+O is consistent within observational uncertainties. However, a small C+N+O enrichment for the faint-SGB, similar to what predicted on theoretical ground, cannot be excluded. The N and Na enrichment of the faint-SGB qualitatively agrees with this population possibly being He-enhanced, as suggested by theory. The iron abundance of the bright and faint-SGB is the same to a level of ~0.10dex, and no other significant difference for the analysed elements has been detected.
- ID:
- ivo://CDS.VizieR/J/MNRAS/444/527
- Title:
- Tully-Fisher distances for Spitzer galaxies
- Short Name:
- J/MNRAS/444/527
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper involves a data release of the observational campaign: Cosmicflows with Spitzer (CFS). Surface photometry of the 1270 galaxies constituting the survey is presented. An additional ~400 galaxies from various other Spitzer surveys are also analysed. CFS complements the Spitzer Survey of Stellar Structure in Galaxies, that provides photometry for an additional 2352 galaxies, by extending observations to low galactic latitudes (|b|<30{deg}). Among these galaxies are calibrators, selected in the K band, of the Tully-Fisher relation. The addition of new calibrators demonstrates the robustness of the previously released calibration. Our estimate of the Hubble constant using supernova host galaxies is unchanged, H_0_=75.2+/-3.3km/s/Mpc. Distance-derived radial peculiar velocities, for the 1935 galaxies with all the available parameters, will be incorporated into a new data release of the Cosmicflows project. The size of the previous catalogue will be increased by 20 percent, including spatial regions close to the Zone of Avoidance.
- ID:
- ivo://CDS.VizieR/J/AJ/118/1489
- Title:
- Tully-Fisher peculiar velocities in 52 clusters
- Short Name:
- J/AJ/118/1489
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have obtained I-band Tully-Fisher (T-F) measurements for 522 late-type galaxies in the fields of 52 rich Abell clusters distributed throughout the sky between ~50 and 200h^-1^Mpc. Here we estimate corrections to the data for various forms of observational bias, most notably Malmquist and cluster population incompleteness bias. The bias-corrected data are applied to the construction of an I-band T-F template, resulting in a relation with a dispersion of 0.38mag and a kinematic zero point accurate to 0.02mag. This represents the most accurate T-F template relation currently available. Individual cluster T-F relations are referred to the average template relation to compute cluster peculiar motions. The line-of-sight dispersion in the peculiar motions is 341x93km/s, in general agreement with that found for the cluster sample of Giovanelli and coworkers.
- ID:
- ivo://CDS.VizieR/J/A+A/420/97
- Title:
- Tully-Fisher relation at 0.1<z<1.0
- Short Name:
- J/A+A/420/97
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using the Very Large Telescope in Multi Object Spectroscopy mode, we have observed a sample of 113 field spiral galaxies in the FORS Deep Field (FDF) with redshifts in the range 0.1<z<1.0. The galaxies were selected based on apparent brightness (R<23) and encompass all late spectrophotometric types from Sa to Sdm/Im. Spatially resolved rotation curves have been extracted for 77 galaxies and fitted with synthetic velocity fields taking into account all observational effects from inclination and slit misalignment to seeing and slit width. We also compared different shapes for the intrinsic rotation curve. To obtain robust values of Vmax, our analysis is focused on galaxies with rotation curves that extend well into the region of constant rotation velocity at large radii. If the slope of the local Tully-Fisher relation (TFR) is held fixed, we find evidence for a mass-dependent luminosity evolution which is as large as up to 2mag for the lowest-mass galaxies, but is small or even negligible for the highest-mass systems in our sample. In effect, the TFR slope is shallower at z~0.5 in comparison to the local sample. We argue for a mass-dependent evolution of the mass-to-light ratio. An additional population of blue, low-mass spirals does not seem a very appealing explanation. The flatter tilt we find for the distant TFR is in contradiction to the predictions of recent semi-analytic simulations.
- ID:
- ivo://CDS.VizieR/J/MNRAS/417/2347
- Title:
- Tully-Fisher relation for SDSS galaxies
- Short Name:
- J/MNRAS/417/2347
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this paper, we derive scaling relations between photometric observable quantities and disc galaxy rotation velocity V_rot_ or Tully-Fisher relations (TFRs). Our methodology is dictated by our purpose of obtaining purely photometric, minimal-scatter estimators of V_rot_ applicable to large galaxy samples from imaging surveys. To achieve this goal, we have constructed a sample of 189 disc galaxies at redshifts z<0.1 with long-slit H{alpha} spectroscopy from Pizagno et al. (2007, Cat. J/AJ/134/945) and new observations. By construction, this sample is a fair subsample of a large, well-defined parent disc sample of ~170000 galaxies selected from the Sloan Digital Sky Survey Data Release 7 (SDSS DR7).
![To the extent possible under law, the publisher has waived all copyright and related or neighboring rights to GAVO's ADQL course. For details, see the `Creative Commons CC0 1.0 Public Domain dedication <http://creativecommons.org/publicdomain/zero/1.0/>`_. Of course, you should still give proper credit when using this data as required by good scientific practice. .. image:: /static/img/cc0.png :alt: [CC0]](/registry-search/?f%5Brights_facet%5D%5B%5D=To+the+extent+possible+under+law%2C+the+publisher+has+waived+all+copyright+and+related+or+neighboring+rights+to+GAVO%27s+ADQL+course.++For+details%2C+see+the+%60Creative+Commons+CC0+1.0+Public+Domain+dedication+%3Chttp%3A%2F%2Fcreativecommons.org%2Fpublicdomain%2Fzero%2F1.0%2F%3E%60_.++Of+course%2C+you+should+still+give+proper+credit+when+using+this+data+as+required+by+good+scientific+practice.%0A%0A..+image%3A%3A+%2Fstatic%2Fimg%2Fcc0.png%0A+++%3Aalt%3A+%5BCC0%5D%0A%0A&f%5BvalidationLevel_facet%5D%5B%5D=2){kind=link}