- ID:
- ivo://CDS.VizieR/J/A+A/489/229
- Title:
- NIR photometry of IRAS 19410+2336
- Short Name:
- J/A+A/489/229
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- IRAS 19410+2336 is a young massive star forming region with an intense outflow activity. Outflows are frequently studied in the near-infrared (NIR) since the H_2_ emission in this wavelength range often traces the shocked molecular gas. However, the mechanisms behind the H_2_ emission detected in IRAS 19410+2336 have not been clarified yet. We present here spatially resolved NIR spectroscopy which allows us to verify whether the H_2_ emission originates from thermal emission in shock fronts or from fluorescence excitation by non-ionizing UV photons. Moreover, NIR spectroscopy also offers the possibility of studying the characteristics of the putative driving source(s) of the H_2_ emission by the detection of photospheric and circumstellar spectral features, and of the environmental conditions (e.g. extinction). We obtained long-slit, intermediate-resolution, NIR spectra of IRAS 19410+2336 using LIRIS, the NIR imager/spectrographer mounted on the 4.2m William Herschel Telescope. As a complement, we also obtained J, H and Ks images with the Las Campanas 2.5m Du Pont Telescope, and archival mid-infrared (MIR) Spitzer-images at 3.6, 4.5, 5.8 and 8.0um.
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Search Results
- ID:
- ivo://CDS.VizieR/J/A+AS/126/479
- Title:
- NIR photometry of IRAS sources. III
- Short Name:
- J/A+AS/126/479
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the near infrared photometry of a new sample of 225 IRAS sources, many of them previously unidentified in the literature, selected because their far infrared colours are similar to those shown by known planetary nebulae. The results obtained are used to establish the main source of near infrared emission. Combining this information with the far infrared IRAS data and a few additional criteria we determine the nature and evolutionary stage of all the sources observed so far, including those for which near infrared photometry was previously reported in Papers I (Manchado et al., 1989A&A...214..139M) and II (Garcia-Lario et al., 1990A&AS...82..497G).
- ID:
- ivo://CDS.VizieR/J/AJ/143/43
- Title:
- NIR photometry of NGC 604 star-forming region
- Short Name:
- J/AJ/143/43
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a near-infrared study focused on the detection and characterization of the youngest stellar component of the NGC 604 giant star-forming region in the Triangulum galaxy (M 33). By means of color-color diagrams derived from the photometry of JHK_s_ images taken with the Gemini Near Infrared Imaging and Spectrometer (NIRI), we have found 68 candidate massive young stellar objects. The spatial distribution of these sources matches the areas where previous studies suggested that star formation might be taking place, and the high spatial resolution of our deep NIRI imaging allows us to pinpoint the star-forming knots. An analysis of the fraction of objects that show infrared excess suggests that the star formation is still active, supporting the presence of a second generation of stars being born, although the evidence for or against sequential star formation does not seem to be conclusive.
- ID:
- ivo://CDS.VizieR/J/AJ/154/263
- Title:
- NIR photometry of 77 RR Lyrae stars
- Short Name:
- J/AJ/154/263
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have obtained single-phase near-infrared (NIR) magnitudes in the J and K bands for 77 RR Lyrae (RRL) stars in the Fornax Dwarf Spheroidal Galaxy. We have used different theoretical and empirical NIR period-luminosity-metallicity calibrations for RRL stars to derive their absolute magnitudes, and found a true, reddening-corrected distance modulus of 20.818+/-0.015(statistical)+/-0.116(systematic) mag. This value is in excellent agreement with the results obtained within the Araucaria Project from the NIR photometry of red clump stars (20.858+/-0.013 mag), the tip of the red giant branch (20.84+/-0.04+/-0.14 mag), as well as with other independent distance determinations to this galaxy. The effect of metallicity and reddening is substantially reduced in the NIR domain, making this method a robust tool for accurate distance determination at the 5% level. This precision is expected to reach the level of 3% once the zero points of distance calibrations are refined thanks to the Gaia mission. NIR period-luminosity-metallicity relations of RRL stars are particularly useful for distance determinations to galaxies and globular clusters up to 300 kpc, that lack young standard candles, like Cepheids.
- ID:
- ivo://CDS.VizieR/J/MNRAS/384/1502
- Title:
- NIR photometry of X-ray luminous BCGs
- Short Name:
- J/MNRAS/384/1502
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate the near-infrared evolution of brightest cluster galaxies (BCGs) from a sample of rich galaxy clusters since z~1. By employing an X-ray selection of LX>10^44^erg/s, we limit environmental effects by selecting BCGs in comparably high-density regions. We find a positive relationship between X-ray and near-infrared luminosity for BCGs in clusters with LX>5x10^44^erg/s. Applying a correction for this relation, we reduce the scatter in the BCG absolute magnitude by a factor of 30 per cent. The near-infrared J-K colour evolution demonstrates that the stellar population in BCGs has been in place since at least z=2, and that we expect a shorter period of star formation than that predicted by current hierarchical merger models. We also confirm that there is a relationship between 'blue' J-K colour and the presence of BCG emission lines associated with star formation in cooling flows.
- ID:
- ivo://CDS.VizieR/J/ApJS/211/3
- Title:
- NIR photometry variability in {rho} Oph
- Short Name:
- J/ApJS/211/3
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Presented are the results of a near-IR photometric survey of 1678 stars in the direction of the {rho} Ophiuchus ({rho} Oph) star forming region using data from the 2MASS Calibration Database. For each target in this sample, up to 1584 individual J-, H-, and Ks-band photometric measurements with a cadence of ~1 day are obtained over three observing seasons spanning ~2.5 yr; it is the most intensive survey of stars in this region to date. This survey identifies 101 variable stars with {Delta}Ks-band amplitudes from 0.044 to 2.31 mag and {Delta}(J-Ks) color amplitudes ranging from 0.053 to 1.47 mag. Of the 72 young {rho} Oph star cluster members included in this survey, 79% are variable; in addition, 22 variable stars are identified as candidate members. Based on the temporal behavior of the Ks time-series, the variability is distinguished as either periodic, long time-scale or irregular. This temporal behavior coupled with the behavior of stellar colors is used to assign a dominant variability mechanism. A new period-searching algorithm finds periodic signals in 32 variable stars with periods between 0.49 to 92 days. The chief mechanism driving the periodic variability for 18 stars is rotational modulation of cool starspots while 3 periodically vary due to accretion-induced hot spots. The time-series for six variable stars contains discrete periodic "eclipse-like" features with periods ranging from 3 to 8 days. These features may be asymmetries in the circumstellar disk, potentially sustained or driven by a proto-planet at or near the co-rotation radius. Aperiodic, long time-scale variations in stellar flux are identified in the time-series for 31 variable stars with time-scales ranging from 64 to 790 days. The chief mechanism driving long time-scale variability is variable extinction or mass accretion rates. The majority of the variable stars (40) exhibit sporadic, aperiodic variability over no discernable time-scale. No chief variability mechanism could be identified for these variable stars.
- ID:
- ivo://CDS.VizieR/J/AJ/153/126
- Title:
- NIR polarimetric study in the LMC N159/N160 field
- Short Name:
- J/AJ/153/126
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present near-infrared polarimetric results for the N159/N160 star-forming complex in the Large Magellanic Cloud with SIRPOL, the polarimeter of the Infrared Survey Facility. We separated foreground sources using their visual extinction derived from near-infrared photometric data. The 45 young stellar candidates and 2 high-excitation blobs were matched with our sources, and 12 of them showed high polarization that did not originate from the interstellar dust. We made a polarimetric catalog of 252, 277, and 89 sources at the J, H, and K_s_ bands, respectively. Based on the ratios of the polarization degree between these bands, we verify that the origin of these polarized sources is the dichroic extinction from the interstellar dust aligned by the magnetic field and that the ratios follow a power-law dependence of P_{lambda}_~{lambda}^-0.9^. The linear polarization vectors projected onto the H{alpha} image of the complex turned out to follow the local magnetic field structure. The vector map overlaid on dust and gas emissions shows the close correlation between the magnetic field structure and surrounding interstellar medium. We suggest that the derived magnetic field structure supports the sequential formation scenario of the complex.
- ID:
- ivo://CDS.VizieR/J/MNRAS/437/3603
- Title:
- NIR proper motion catalogue from UKIDSS-LAS
- Short Name:
- J/MNRAS/437/3603
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The United Kingdom Infrared Deep Sky Survey (UKIDSS) Large Area Survey (LAS) began in 2005, with the start of the UKIDSS programme as a 7 year effort to survey roughly 4000deg^2^ at high Galactic latitudes in Y, J, H and K bands. The survey also included a significant quantity of two epoch J band observations, with an epoch baseline greater than 2 years to calculate proper motions. We present a near-infrared proper motion catalogue for the 1500deg^2^ of the two epoch LAS data, which includes 135625 stellar sources and a further 88324 with ambiguous morphological classifications, all with motions detected above the 5{sigma} level. We developed a custom proper motion pipeline which we describe here. Our catalogue agrees well with the proper motion data supplied for a 300deg^2^ subset in the current Wide Field Camera Science Archive (WSA) 10th data release (DR10) catalogue, and in various optical catalogues, but it benefits from a larger matching radius and hence a larger upper proper motion detection limit. We provide absolute proper motions, using LAS galaxies for the relative to absolute correction. By using local second-order polynomial transformations, as opposed to linear transformations in the WSA, we correct better for any local distortions in the focal plane, not including the radial distortion that is removed by the UKIDSS pipeline. We present the results of proper motion searches for new brown dwarfs and white dwarfs. We discuss 41 sources in the WSA DR10 overlap with our catalogue with proper motions >300mas/yr, several of which are new detections. We present 15 new candidate ultracool dwarf binary systems.
- ID:
- ivo://CDS.VizieR/J/ApJS/190/100
- Title:
- NIR proper motion survey using 2MASS
- Short Name:
- J/ApJS/190/100
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have conducted a 4030deg^2^ near-infrared proper motion survey using multi-epoch data from the Two Micron All-Sky Survey (2MASS). We find 2778 proper motion candidates, 647 of which are not listed in SIMBAD. After comparison to Digitized Sky Survey images, we find that 107 of our proper motion candidates lack counterparts at B, R, and I bands and are thus 2MASS-only detections. We present results of spectroscopic follow-up of 188 targets that include the infrared-only sources along with selected optical-counterpart sources with faint reduced proper motions or interesting colors. We also establish a set of near-infrared spectroscopic standards with which to anchor near-infrared classifications for our objects. Among the discoveries are six young field brown dwarfs, five "red L" dwarfs, three L-type subdwarfs, twelve M-type subdwarfs, eight "blue L" dwarfs, and several T dwarfs. We further refine the definitions of these exotic classes to aid future identification of similar objects. We examine their kinematics and find that both the "blue L" and "red L" dwarfs appear to be drawn from a relatively old population.
- ID:
- ivo://CDS.VizieR/J/ApJS/194/10
- Title:
- NIR properties of YSO in the CCCP
- Short Name:
- J/ApJS/194/10
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Great Nebula in Carina (NGC 3372) is the best target to study in detail the process of violent massive star formation and the resulting feedback effects of cloud dispersal and triggered star formation. While the population of massive stars is rather well studied, the associated low-mass stellar population was largely unknown up to now. The near-infrared study in this paper builds on the results of the Chandra Carina Complex Project, that detected 14368 X-ray sources in the 1.4deg^2^ survey region, an automatic source classification study that classified 10714 of these X-ray sources as very likely young stars in Carina, and an analysis of the clustering properties of the X-ray-selected Carina members. In order to determine physical properties of the X-ray-selected stars, most of which were previously unstudied, we used HAWK-I at the ESO Very Large Telescope to conduct a very deep near-IR survey with subarcsecond angular resolution, covering an area of about 1280arcmin^2^. The HAWK-I images reveal more than 600000 individual infrared sources, whereby objects as faint as J~23, H~22, and Ks~21 are detected at signal-to-noise ratio (S/N)>=3. While less than half of the Chandra X-ray sources have counterparts in the Two Micron All Sky Survey catalog, the ~5mag deeper HAWK-I data reveal infrared counterparts to 6636 (=88.8%) of the 7472 Chandra X-ray sources in the HAWK-I field. We analyze near-infrared color-color and color-magnitude diagrams to derive information about the extinctions, infrared excesses (as tracers for circumstellar disks), ages, and masses of the X-ray-selected objects.
