- ID:
- ivo://CDS.VizieR/J/A+A/495/157
- Title:
- Interstellar extinction in Galactic Center
- Short Name:
- J/A+A/495/157
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use the Spitzer IRAC catalogue of the Galactic Center (GC) point sources (Ramirez et al., 2008ApJS..175..147R) and combine it with new isochrones (Marigo et al., 2008A&A...482..883M) to derive extinctions based on photometry of red giants and asymptotic giant branch (AGB) stars. This new extinction map extends to much higher values of Av than previously available. Our new extinction map of the GC region covers 2.0x1.4deg^2^ (280x200pc at a distance of 8kpc). We apply it to deredden the LPVs found by Glass et al. (2001, Cat. <J/MNRAS/321/77>) near the GC. We make period-magnitude diagrams and compare them to those from other regions of different metallicity. The Glass-LPVs follow well-defined period-luminosity relations (PL) in the IRAC filter bands at 3.6 , 4.5, 5.8, and 8.0um. The period-luminosity relations are similar to those in the Large Magellanic Cloud, suggesting that the PL relation in the IRAC bands is universal. We use ISOGAL data to derive mass-loss rates and find for the Gl ass-LPV sample some correlation between mass-loss and pulsation period, as expected theoretically. The GC has an excess of high luminosity and long period LPVs compared to the Bulge, which supports previous suggestions that it contains a younger stellar population.
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- ID:
- ivo://CDS.VizieR/II/321
- Title:
- IPHAS DR2 Source Catalogue
- Short Name:
- II/321
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The INT/WFC Photometric H-Alpha Survey of the Northern Galactic Plane (IPHAS) is a 1860 deg^2^ imaging survey of the Northern Milky Way at red visible wavelengths. It covers Galactic latitudes |b|<5{deg} and longitudes l=30 to 215{deg} in the broad-band r, i and narrow-band H-alpha filters using the Wide Field Camera (WFC) on the 2.5-m Isaac Newton Telescope (INT) in La Palma. IPHAS Data Release 2 (DR2) is the first quality-controlled and globally calibrated source catalogue derived from the survey, providing single-epoch photometry for 219 million unique sources across 92% of the footprint. The observations were carried out between 2003 and 2012 at a median seeing of 1.1 arcsec (sampled at 0.33 arcsec/pixel) and to a mean 5-sigma depth of 21.2 (r), 20.0 (i) and 20.3 (H-alpha). The photometric calibration is in the Vega magnitude system and carries an external precision of 0.03mag (root-mean-square error). The catalogue includes all the sources which have been detected at a signal-to-noise ratio of 5 or better in at least one band. Many applications will require a combination of quality criteria to be applied to avoid faint stars or confused sources. The choice of quality criteria tensions completeness against reliability, and hence depends on the requirements of a project. To aid users, the data release paper (arXiv:1406.4862) recommends two sets of quality criteria, named "a10" and "a10point", which should satisfy most projects. As a minimum, the "a10" criteria select objects which have been detected at the minimum level of 10-sigma in all bands, without being saturated. Additional constraints are provided by the "a10point" criteria, which require objects to be point sources free of blending, unaffected by nearby bright stars, as well as being unsaturated >10-sigma detections in all bands. Sources in both categories are flagged in the catalogue using the boolean columns a10 and a10point. Imaging and auxiliary data are available from the project website (www.iphas.org).
- ID:
- ivo://CDS.VizieR/J/A+AS/80/149
- Title:
- IRAS Sources behind the Solar circle
- Short Name:
- J/A+AS/80/149
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- CO (J=1->0) has been observed with the 15-m SEST and the 30-m IRAM telescope in the direction of 1302 IRAS sources with colors of star forming regions located within 10 deg of the galactic plane in the interval between 85 and 280 deg. Emission components with line profiles that are non-Gaussian (showing, e.g., possible self-absorption or wings) are identified; this information may serve as a basis for selecting sources for future research. For all components, kinematic heliocentric and galactocentric distances, and distances from the galactic plane are derived. For those components which may be associated with the IRAS sources, bolometric luminosities are derived. These data will be analyzed and compared with HI data in subsequent papers.
- ID:
- ivo://CDS.VizieR/J/A+AS/98/589
- Title:
- IRAS Sources behind the Solar circle
- Short Name:
- J/A+AS/98/589
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- (no description available)
- ID:
- ivo://CDS.VizieR/J/ApJ/795/22
- Title:
- Iron abundance of Terzan 5 stars
- Short Name:
- J/ApJ/795/22
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present new determinations of the iron abundance for 220 stars belonging to the stellar system Terzan 5 in the Galactic bulge. The spectra have been acquired with FLAMES at the Very Large Telescope of the European Southern Observatory and DEIMOS at the Keck II Telescope. This is by far the largest spectroscopic sample of stars ever observed in this stellar system. From this data set, a subsample of targets with spectra unaffected by TiO bands was extracted and statistically decontaminated from field stars. Once combined with 34 additional stars previously published by our group, a total sample of 135 member stars covering the entire radial extent of the system has been used to determine the metallicity distribution function of Terzan 5. The iron distribution clearly shows three peaks: a super-solar component at [Fe/H]=~0.25 dex, accounting for ~29% of the sample, a dominant sub-solar population at [Fe/H]=~-0.30 dex, corresponding to ~62% of the total, and a minor (6%) metal-poor component at [Fe/H]=~-0.8 dex. Such a broad, multi-modal metallicity distribution demonstrates that Terzan 5 is not a genuine globular cluster but the remnant of a much more complex stellar system.
- ID:
- ivo://CDS.VizieR/J/AJ/154/201
- Title:
- IR properties of stellar bowshock nebulae
- Short Name:
- J/AJ/154/201
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Arcuate infrared nebulae are ubiquitous throughout the Galactic Plane and are candidates for partial shells, bubbles, or bowshocks produced by massive runaway stars. We tabulate infrared photometry for 709 such objects using images from the Spitzer Space Telescope, the Wide-field Infrared Explorer, and the Herschel Space Observatory (HSO). Of the 709 objects identified at 24 or 22 {mu}m, 422 are detected at the HSO 70 {mu}m bandpass. Of these, only 39 are detected at HSO 160 {mu}m. The 70 {mu}m peak surface brightnesses are 0.5-2.5 Jyr/arcmin^2^. Color temperatures calculated from the 24 to 70 {mu}m ratios range from 80 to 400 K. Color temperatures from 70 to 160 {mu}m ratios are systematically lower, 40-200 K. Both of these temperature are, on average, 75% higher than the nominal temperatures derived by assuming that dust is in steady-state radiative equilibrium. This may be evidence of stellar wind bowshocks sweeping up and heating-possibly fragmenting but not destroying-interstellar dust. Infrared luminosity correlates with standoff distance, R_0_, as predicted by published hydrodynamical models. Infrared spectral energy distributions are consistent with interstellar dust exposed to either single radiant energy density, U=10^3^-10^5^ (in more than half of the objects) or a range of radiant energy densities U_min_=25 to U_max_=10^3^-10^5^ times the mean interstellar value for the remainder. Hence, the central OB stars dominate the energetics, making these enticing laboratories for testing dust models in constrained radiation environments. The spectral energy densities are consistent with polycyclic aromatic hydrocarbon fractions q_PAH_~<1% in most objects.
- ID:
- ivo://CDS.VizieR/J/MNRAS/469/2163
- Title:
- JCMT Plane Survey. first complete data release
- Short Name:
- J/MNRAS/469/2163
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first data release of the James Clerk Maxwell Telescope Plane Survey (JPS), the JPS Public Release 1. JPS is an 850-{mu}m continuum survey of six fields in the northern inner Galactic plane in a longitude range of l=7{deg}-63{deg}, made with the Submillimetre Common-User Bolometer Array 2. This first data release consists of emission maps of the six JPS regions with an average pixel-to-pixel noise of 7.19mJy/beam, when smoothed over the beam, and a compact source catalogue containing 7813 sources. The 95 per cent completeness limits of the catalogue are estimated at 0.04Jy/beam and 0.3Jy for the peak and integrated flux densities, respectively. The emission contained in the compact source catalogue is 42+/-5 per cent of the total and, apart from the large-scale (greater than 8 arcmin) emission, there is excellent correspondence with features in the 500-{mu}m Herschel maps. We find that, with two-dimensional matching, 98 {\pm} 2 per cent of sources within the fields centred at l=20{deg}, 30{deg}, 40{deg} and 50{deg} are associated with molecular clouds, with 91+/-3 per cent of the l=30{deg} and 40{deg} sources associated with dense molecular clumps. Matching the JPS catalogue to Herschel 70-{mu}m sources, we find that 38+/-1 per cent of sources show evidence of ongoing star formation. The JPS Public Release 1 images and catalogue will be a valuable resource for studies of star formation in the Galaxy and the role of environment and spiral arms in the star formation process.
- ID:
- ivo://CDS.VizieR/J/MNRAS/453/4264
- Title:
- JCMT Plane Survey: l=30{deg} field
- Short Name:
- J/MNRAS/453/4264
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present early results from the JCMT (James Clerk Maxwell Telescope) Plane Survey (JPS), which has surveyed the northern inner Galactic plane between longitudes l=7{deg} and l=63{deg} in the 850-{mu}m continuum with SCUBA-2 (Submm Common-User Bolometer Array 2), as part of the JCMT Legacy Survey programme. Data from the l=30{deg} survey region, which contains the massive-star-forming regions W43 and G29.96, are analysed after approximately 40 percent of the observations had been completed. The pixel-to-pixel noise is found to be 19mJy/beam after a smooth over the beam area, and the projected equivalent noise levels in the final survey are expected to be around 10mJy/beam. An initial extraction of compact sources was performed using the FellWalker method, resulting in the detection of 1029 sources above a 5{sigma} surface-brightness threshold. The completeness limits in these data are estimated to be around 0.2Jy/beam (peak flux density) and 0.8 Jy (integrated flux density) and are therefore probably already dominated by source confusion in this relatively crowded section of the survey. The flux densities of extracted compact sources are consistent with those of matching detections in the shallower APEX (Atacama Pathfinder Experiment) Telescope Large Area Survey of the Galaxy (ATLASGAL) survey. We analyse the virial and evolutionary state of the detected clumps in the W43 star-forming complex and find that they appear younger than the Galactic-plane average.
- ID:
- ivo://CDS.VizieR/J/ApJ/857/54
- Title:
- JHKs photometry of VVV RR Lyrae stars
- Short Name:
- J/ApJ/857/54
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- RR Lyrae stars (RRLs) are tracers of the Milky Way's fossil record, holding valuable information on its formation and early evolution. Owing to the high interstellar extinction endemic to the Galactic plane, distant RRLs lying at low Galactic latitudes have been elusive. We attained a census of 1892 high-confidence RRLs by exploiting the near-infrared photometric database of the VVV survey's disk footprint spanning ~70{deg} of Galactic longitude, using a machine-learned classifier. Novel data-driven methods were employed to accurately characterize their spatial distribution using sparsely sampled multi-band photometry. The RRL metallicity distribution function (MDF) was derived from their K_s_-band light-curve parameters using machine-learning methods. The MDF shows remarkable structural similarities to both the spectroscopic MDF of red clump giants and the MDF of bulge RRLs. We model the MDF with a multi-component density distribution and find that the number density of stars associated with the different model components systematically changes with both the Galactocentric radius and vertical distance from the Galactic plane, equivalent to weak metallicity gradients. Based on the consistency with results from the ARGOS survey, three MDF modes are attributed to the old disk populations, while the most metal-poor RRLs are probably halo interlopers. We propose that the dominant [Fe/H] component with a mean of -1dex might correspond to the outskirts of an ancient Galactic spheroid or classical bulge component residing in the central Milky Way. The physical origins of the RRLs in this study need to be verified by kinematical information.
- ID:
- ivo://CDS.VizieR/J/A+A/559/A98
- Title:
- JK photometry in BUL_SC9 and BUL_SC29
- Short Name:
- J/A+A/559/A98
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In some scenarios for the formation of the Milky Way bulge, the stellar population at the edges of the boxy bulge may be younger than those on the minor axis or close to the Galactic center. So far the only bulge region where deep color-magnitude diagrams have been obtained is indeed along the minor axis. To overcome this limitation, we aim to age-date the bulge stellar populations far away from the bulge minor axis. Color-magnitude diagrams and luminosity functions have been obtained from deep near-IR VLT/HAWK-I images taken at the two Southern corners of the boxy bulge, i.e., near the opposite edges of the Galactic bar. The foreground disk contamination has been statistically removed using a pure disk field observed with the same instrument and located approximately at similar Galactic latitudes of the two bulge fields and ~30{deg} in longitude away from the Galactic center. For each bulge field, mean reddening and distance are determined using the position of red clump stars, and the metallicity distribution is derived photometrically using the color distribution of stars in the upper red giant branch.
