Search

Start Over Subject photometry Content Level Research
1551. Deep MIPS observations of IC 348 nebula
ID:
ivo://CDS.VizieR/J/AJ/138/703
Title:
Deep MIPS observations of IC 348 nebula
Short Name:
J/AJ/138/703
Date:
21 Oct 2021
Publisher:
CDS
Description:
We describe new, deep MIPS photometry and new high signal-to-noise optical spectroscopy of the 2.5Myr old IC 348 Nebula. To probe the properties of the IC 348 disk population, we combine these data with previous optical/infrared photometry and spectroscopy to identify stars with gas accretion, to examine their mid-IR colors, and to model their spectral energy distributions.
1552. Deep Multicolor Survey. IV.
ID:
ivo://CDS.VizieR/J/ApJS/119/189
Title:
Deep Multicolor Survey. IV.
Short Name:
J/ApJS/119/189
Date:
21 Oct 2021
Publisher:
CDS
Description:
This stellar catalog contains 19,494 objects from the Deep Multicolor Survey (DMS) and results from follow-up spectroscopic observations of 234 objects in the catalog. The DMS is based on CCD imaging with the Mayall 4 m telescope in U, B, V, R', I75, and I86 and covers 0.83 deg^2 in six fields at high Galactic latitude. The survey reached 5 sigma limiting magnitudes of 22.1 in I86 to 23.8 in B. The catalog gives positions, magnitudes and error estimates, and classification codes in the six filter bands for all the objects. In addition, the survey is useful for the study of faint field galaxies and of faint stars at high Galactic latitude. Presented are tables that summarize the spectroscopic results for the 55 quasars, 44 compact narrow emission-line galaxies, and 135 stars in the DMS that we have confirmed to date. Also included are illustrations of all the spectra.
1553. Deep NIR catalogue of HIZOA galaxies
ID:
ivo://CDS.VizieR/J/MNRAS/462/3386
Title:
Deep NIR catalogue of HIZOA galaxies
Short Name:
J/MNRAS/462/3386
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a deep near-infrared (NIR; J, H, and K_s_ bands) photometric catalogue of sources from the Parkes HI Zone of Avoidance (HIZOA) survey, which forms the basis for an investigation of the matter distribution in the Zone of Avoidance. Observations were conducted between 2006 and 2013 using the Infrared Survey Facility (IRSF), a 1.4-m telescope situated at the South African Astronomical Observatory site in Sutherland. The images cover all 1108 HIZOA detections and yield 915 galaxies. An additional 105 bright 2MASS galaxies in the southern ZOA were imaged with the IRSF, resulting in 129 galaxies. The average K_s_-band seeing and sky background for the survey are 1.38-arcsec and 20.1mag, respectively. The detection rate as a function of stellar density and dust extinction is found to depend mainly on the HI mass of the HI detected galaxies, which in principal correlates with the NIR brightness of the spiral galaxies. The measured isophotal magnitudes are of sufficient accuracy (errors ~0.02mag) to be used in a Tully-Fisher analysis. In the final NIR catalogue, 285 galaxies have both IRSF and 2MASS photometry (180 HIZOA plus 105 bright 2MASX galaxies). The K_s_-band isophotal magnitudes presented in this paper agree, within the uncertainties, with those reported in the 2MASX catalogue. Another 30 galaxies, from the HIZOA northern extension, are also covered by UKIDSS Galactic Plane Survey (GPS) images, which are one magnitude deeper than our IRSF images. A modified version of our photometry pipeline was used to derive the photometric parameters of these UKIDSS galaxies. Good agreement was found between the respective K_s_-band isophotal magnitudes. These comparisons confirm the robustness of the isophotal parameters and demonstrate that the IRSF images do not suffer from foreground contamination, after star removal, nor underestimate the isophotal fluxes of ZoA galaxies.
1554. Deep NIR imaging of {rho} Oph cloud core
ID:
ivo://CDS.VizieR/J/ApJ/719/550
Title:
Deep NIR imaging of {rho} Oph cloud core
Short Name:
J/ApJ/719/550
Date:
21 Oct 2021
Publisher:
CDS
Description:
A search for young substellar objects in the {rho} Oph cloud core region has been made with the aid of multiband profile-fitting point-source photometry of the deep-integration Combined Calibration Scan images of the 2MASS extended mission in the J, H, and Ks bands, and Spitzer IRAC images at 3.6, 4.5, 5.8, and 8.0um. The field of view of the combined observations was 1{deg}x9.3', and the 5{sigma} limiting magnitude at J was 20.5. Comparison of the observed spectral energy distributions with the predictions of the COND and DUSTY models, for an assumed age of 1Myr, supports the identification of many of the sources with brown dwarfs and enables the estimation of effective temperature, T_eff_. The cluster members are then readily distinguishable from background stars by their locations on a plot of flux density versus T_eff_. The range of estimated T_eff_ values extends down to ~750K which, based on the COND model, would suggest the presence of objects of sub-Jupiter mass. The results also suggest that the mass function for the {rho} Oph cloud resembles that of the {sigma} Orionis cluster based on a recent study, with both rising steadily toward lower masses. The other main result from our study is the apparent presence of a progressive blueward skew in the distribution of J-H and H-Ks colors, such that the blue end of the range becomes increasingly bluer with increasing magnitude. We suggest that this behavior might be understood in terms of the "ejected stellar embryo" hypothesis, whereby some of the lowest-mass brown dwarfs could escape to locations close to the front edge of the cloud, and thereby be seen with less extinction.
1555. Deep NIR photometry of HI galaxies in ZoA
ID:
ivo://CDS.VizieR/J/MNRAS/443/41
Title:
Deep NIR photometry of HI galaxies in ZoA
Short Name:
J/MNRAS/443/41
Date:
21 Oct 2021
Publisher:
CDS
Description:
Current studies of the peculiar velocity flow field in the local Universe are limited by either the lack of detection or accurate photometry for galaxies at low Galactic latitudes. The contribution to the dynamics of the Local Group of the largely unknown mass distribution in this 'Zone of Avoidance' (ZoA) remains controversial. We present here the results of a pilot project to obtain deep near-infrared (NIR) observations of galaxies detected in the systematic Parkes deep HI survey of the ZoA (HIZOA) - 578 galaxies with recession velocities out to 6000km/s were observed with the 1.4m InfraRed Survey Facility SIRIUS (Simultaneous InfraRed Imager for Unbiased Surveys) camera providing J, H and Ks imaging 2mag deeper than 2MASS. After star subtraction, the resulting isophotal magnitudes and inclinations of ZoA galaxies are of sufficient accuracy (magnitude errors under 0.1mag even at high extinction) to ultimately be used to determine cosmic flow fields 'in' the ZoA via the NIR Tully-Fisher relation. We further used the observed NIR colours to assess the ratio of the true extinction to the Diffuse Infrared Background Experiment/IRAS extinction deep into the dust layers of the Milky Way. The derived ratio was found to be 0.87 across the HIZOA survey region with no significant variation with Galactic latitude or longitude. This value is in excellent agreement with the completely independently derived factor of 0.86 by Schlafly & Finkbeiner (2010ApJ...725.1175S) based on Sloan data far away from the Milky Way.
1556. Deep OB star population in Carina
ID:
ivo://CDS.VizieR/J/MNRAS/465/1807
Title:
Deep OB star population in Carina
Short Name:
J/MNRAS/465/1807
Date:
21 Oct 2021
Publisher:
CDS
Description:
Massive OB stars are critical to the ecology of galaxies, and yet our knowledge of OB stars in the Milky Way, fainter than V~12, remains patchy. Data from the VST Photometric H-alpha Survey (VPHAS+) permit the construction of the first deep catalogues of blue excess-selected OB stars, without neglecting the stellar field. A total of 14900 candidates with 2MASS cross-matches are blue-selected from a 42 square-degree region in the Galactic longitude range 282{deg}<l<293{deg} Spectral energy distribution fitting is performed on these candidates' combined VPHAS+ u/g/r/i and 2MASS J/H/K magnitudes. This delivers: effective temperature constraints, statistically separating O from early-B stars; high-quality extinction parameters, A_0_ and R_V_ (random errors typically <0.1). The high confidence O-B2 candidates number 5915 and a further 5170 fit to later B spectral type. Spectroscopy of 276 of the former confirms 97% of them. The fraction of emission line stars among all candidate B stars is 7-8%. Greyer (R_V_>3.5) extinction laws are ubiquitous in the region, over the distance range 2.5-3kpc to ~10kpc. Near prominent massive clusters, R_V_ tends to rise, with particularly large and chaotic excursions to R_V_~5 seen in the Carina Nebula. The data reveal a hitherto unnoticed association of 108 O-B2 stars around the O5If+ star LSS 2063 (l=289.77{deg}, b=-1.22{deg}). Treating the OB star scale-height as a constant within the thin disk, we find an orderly mean relation between extinction (A_0_) and distance in the Galactic longitude range, 287.6{deg}<l< 293.5{deg}, and infer the subtle onset of thin-disk warping. A halo around NGC 3603, roughly a degree in diameter, of ~500 O-B2 stars with 4<A_0_(mag)<7 is noted.
1557. Deep optical and infrared photometry of Sh2-305
ID:
ivo://CDS.VizieR/J/ApJ/891/81
Title:
Deep optical and infrared photometry of Sh2-305
Short Name:
J/ApJ/891/81
Date:
17 Jan 2022 00:38:10
Publisher:
CDS
Description:
Using our deep optical and near-infrared photometry along with multiwavelength archival data, we here present a detailed study of the Galactic HII region Sh 2-305 to understand the star/star-cluster formation. On the basis of excess infrared emission, we have identified 116 young stellar objects (YSOs) within a field of view of ~18.5'x18.5' around Sh 2-305. The average age, mass, and extinction (AV) for this sample of YSOs are 1.8Myr, 2.9M_{sun}_, and 7.1mag, respectively. The density distribution of stellar sources along with minimal spanning tree calculations on the location of YSOs reveals at least three stellar subclusterings in Sh 2-305. One cluster is seen toward the center (i.e., Mayer 3), while the other two are distributed toward the north and south directions. Two massive O-type stars (VM2 and VM4; ages ~5Myr) are located at the center of the Sh 2-305 HII region. The analysis of the infrared and radio maps traces the photon-dominant regions (PDRs) in Sh 2-305. The association of the younger generation of stars with the PDRs is also investigated in Sh2-305. This result suggests that these two massive stars might have influenced the star formation history in Sh 2-305. This argument is also supported by the calculation of various pressures driven by massive stars, the slope of the mass function/K-band luminosity function, star formation efficiency, fraction of Class I sources, and mass of the dense gas toward the subclusterings in Sh 2-305.
1558. Deep optical photometry in M31
ID:
ivo://CDS.VizieR/J/ApJS/184/152
Title:
Deep optical photometry in M31
Short Name:
J/ApJS/184/152
Date:
21 Oct 2021
Publisher:
CDS
Description:
Using the Advanced Camera for Surveys on the Hubble Space Telescope, we have obtained deep optical images reaching well below the oldest main-sequence turnoff in six fields of the Andromeda Galaxy. The fields fall at four positions on the southeast minor axis, one position in the giant stellar stream, and one position on the northeast major axis. These data were obtained as part of three large observing programs designed to probe the star formation history of the stellar population in various structures of the galaxy. In this paper, we present the images, catalogs, and artificial star tests for these observing programs as a supplement to the analyses published previously. These high-level science products are also archived at the Multimission Archive at the Space Telescope Science Institute.
1559. Deep photometry of NGC 5694 and Terzan 8
ID:
ivo://CDS.VizieR/J/A+AS/82/71
Title:
Deep photometry of NGC 5694 and Terzan 8
Short Name:
J/A+AS/82/71
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present deep CCD photometries for the little known metal-poor clusters NGC 5694 and Terzan 8 down to V~24. NGC 5694 has a blue horizontal branch, a very high radial velocity, a metallicity of [Fe/H]=-1.65+/-0.06, a reddening of E(B-V)=0.10+/-0.03, and an apparent distance modulus of (m-M)_v_=17.82+/-0.15. It is located at 26.0+/-1.8kpc from the galactic center. The helium content derived from the ratio between the number of stars on the horizontal branch and the giant and asymptotic giant branches is consistent with that obtained for other clusters. Terzan 8 is a metal-poor ([Fe/H]=-1.81+/-0.10) moderately reddened (E(B-V)=0.20+/-0.05) cluster with a blue horizontal branch and apparent distance modulus of (m-M)_v_=17.25+/-0.15. It is located at 13.8+/-2.0 kpc from the galactic center. The c-m diagram and the luminosity function of NGC 5694 and Terzan 8 are similar to the M92 ones. NGC 5694 and Terzan 8 have ages close to that of the "classical" globular cluster M92.
1560. Deep spectroscopy in the GOODS fields
ID:
ivo://CDS.VizieR/J/ApJ/741/115
Title:
Deep spectroscopy in the GOODS fields
Short Name:
J/ApJ/741/115
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present new measures of the evolving scaling relations between stellar mass, luminosity and rotational velocity for a morphologically inclusive sample of 129 disk-like galaxies with z_AB_<22.5 in the redshift range 0.2<z<1.3, based on spectra from DEep Imaging Multi-Object Spectrograph on the Keck II telescope, multi-color Hubble Space Telescope (HST) Advanced Camera for Surveys photometry, and ground-based Ks-band imaging. A unique feature of our survey is the extended spectroscopic integration times, leading to significant improvements in determining characteristic rotational velocities for each galaxy. Rotation curves are reliably traced to the radius where they begin to flatten for ~90% of our sample, and we model the HST-resolved bulge and disk components in order to accurately de-project our measured velocities, accounting for seeing and dispersion. We demonstrate the merit of these advances by recovering an intrinsic scatter on the stellar mass Tully-Fisher relation a factor of two to three less than in previous studies at intermediate redshift and comparable to that of locally determined relations. With our increased precision, we find that the relation is well established by <z>~1, with no significant evolution to <z>~0.3, {Delta}M_*_~0.04+/-0.07dex. A clearer trend of evolution is seen in the B-band Tully-Fisher relation corresponding to a decline in luminosity of {Delta}M_B_~0.85+/-0.28 magnitudes at fixed velocity over the same redshift range, reflecting the changes in star formation over this period. As an illustration of the opportunities possible when gas masses are available for a sample such as ours, we show how our dynamical and stellar mass data can be used to evaluate the likely contributions of baryons and dark matter to the assembly history of spiral galaxies.