- ID:
- ivo://CDS.VizieR/J/ApJ/606/929
- Title:
- IR to mm observations of IRAS 18317-0757
- Short Name:
- J/ApJ/606/929
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present high-resolution, multiwavelength-continuum, and molecular-line images of the massive star forming region IRAS 18317-0757. The global infrared through millimeter spectral energy distribution can be approximated by a two-temperature model (25 and 63K) with a total luminosity of approximately log(L/L_{sun}_)=5.2. Previous submillimeter imaging resolved this region into a cluster of five dust cores, one of which is associated with the ultracompact HII region G23.955+0.150, and another with a water maser. In our new 2.7mm continuum image obtained with BIMA, only the UCHII region is detected, with total flux and morphology in good agreement with the free-free emission in the VLA centimeter-wave maps. For the other four objects, the nondetections at 2.7mm and in the MSX mid-infrared bands are consistent with cool dust emission with a temperature of 13-40K and a luminosity of 1000-40000L_{sun}_. By combining single-dish and interferometric data, we have identified over two dozen virialized C^18^O cores in this region that contain ~40% of the total molecular gas mass present.
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7212. IRTS carbon stars
- ID:
- ivo://CDS.VizieR/J/PASP/117/199
- Title:
- IRTS carbon stars
- Short Name:
- J/PASP/117/199
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have identified 139 cool carbon stars in the near-infrared spectrophotometric survey of the Infrared Telescope in Space (IRTS) from the conspicuous presence of molecular absorption bands at 1.8, 3.1, and 3.8{mu}m. Among them, 14 are new bright (K~4.0-7.0) Carbon stars. We find a trend relating the 3.1{mu}m band strength to the (K-L') color index, which is known to correlate with mass-loss rate. This could be an effect of a relation between the depth of the 3.1{mu}m feature and the degree of development of the extended stellar atmosphere where dust starts to form.
- ID:
- ivo://CDS.VizieR/J/AJ/155/99
- Title:
- IR variability among YSOs in the Serpens South cluster
- Short Name:
- J/AJ/155/99
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a time-variability study of young stellar objects (YSOs) in the Serpens South cluster performed at 3.6 and 4.5 {mu}m with the Spitzer Space Telescope; this study is part of the Young Stellar Object VARiability project. We have collected light curves for more than 1500 sources, including 85 cluster members, over 38 days. This includes 44 class I sources, 19 sources with flat spectral energy distributions (SEDs), 17 class II sources, and five diskless YSO candidates. We find a high variability fraction among embedded cluster members of ~70%, whereas young stars without a detectable disk display no variability. We detect periodic variability for 32 sources with periods primarily in the range of 0.2-14 days and a subset of fast rotators thought to be field binaries. The timescale for brightness changes are shortest for stars with the most photospheric SEDs and longest for those with flat or rising SEDs. While most variable YSOs become redder when fainter, as would be expected from variable extinction, about 10% get bluer as they get fainter. One source, SSTYSV J183006.13-020108.0, exhibits "cyclical" color changes.
- ID:
- ivo://CDS.VizieR/J/ApJ/826/209
- Title:
- IRX-{beta} relation of HII regions in NGC628
- Short Name:
- J/ApJ/826/209
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- It has been found that the infrared-to-ultraviolet luminosity ratio (IRX) and ultraviolet spectral slope ({beta}) have a tight correlation in starburst galaxies, while in normal galaxies the relation is deviated and has a much larger scatter. Star formation regions are much simpler in both morphology and physical properties than galaxies, so their photometric and spectroscopic properties are more easily and accurately determined. We have used the integral field spectroscopy and multiband photometric images to study the IRX-{beta} relation of HII regions in a nearby galaxy, NGC 628. There are obvious correlations between the D_n_ (4000), stellar population age, star formation rate, especially H{alpha} equivalent width EW(H{alpha}), and deviation distance d_p_ from the starburst IRX-{beta} relation. However, there is little correlation between the Balmer decrement, metallicity, and d_p_. It is much more complicated than expected, so that we cannot introduce a single second parameter to describe the scatter and deviation of the HII region IRX-{beta} relation.
- ID:
- ivo://CDS.VizieR/B/int
- Title:
- Isaac Newton Telescope Wide Field Survey
- Short Name:
- B/int
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The INT Wide Field Survey (WFS) is using the Wide Field Camera (~0.3 square degrees) on the 2.5m Isaac Newton Telescope (INT). The project was initiated in August 1998 and is expected to have a duration of up to five years. Multicolour data will be obtained over 200+ square degrees to a typical depth of ~25 mag (u' through z'). The data is publically accessible via the Cambridge Astronomical Survey Unit to UK and NL communities from day one, with access to the rest of the world after one year. This observation log lists all observations older than the one year proprietary period.
- ID:
- ivo://CDS.VizieR/J/PAZh/43/859
- Title:
- ISGRI type I X-ray bursts (2003-2015)
- Short Name:
- J/PAZh/43/859
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of our analysis of the JEM-X/INTEGRAL data obtained from January 2003 to January 2015 aimed at searching for type I X-ray bursts from known and new bursters. Such bursts are caused by thermonuclear explosions on the surface of a neutron star. We have searched for bursts in the records of the count rate of the JEM-X detectors in the 3-20keV energy band. We have separately reconstructed and analyzed the light curves of 104 X-ray bursters known to date based on the JEM-X data. A similar search for bursts was previously carried out in the 15-25keV data from the IBIS/ISGRI telescope onboard the INTEGRAL observatory obtained in 2003-2009. We have continued to analyze the data from this telescope up until the observations in January 2015. The joint catalog of bursts detected by the two instruments includes 2201 events; their basic parameters are given. The large size of the sample of bursts makes it one of the most representative of the existing one and allows various statistical studies of bursts to be performed. In particular, we have constructed the dependence of the mean rate of type I bursts from bursters on the luminosity (accretion rate), revealed an appreciable burst rate from sources with a near-Eddington luminosity, and investigated the population of multiple bursts with a recurrence time much shorter than the time it takes for a critical mass of matter required for the initiation of an explosion to be accumulated on the neutron star surface. Almost all of the detected bursts are associated with already known bursters,we have found only one previously unknown burster, IGRJ17380-3749, in the archival data, and one more known, but poorly studied source, AX J1754.2-2754, has been identified as a burster. Several similar sources have previously been identified as bursters directly during the INTEGRAL observations.
- ID:
- ivo://CDS.VizieR/J/ApJ/850/137
- Title:
- ISLAndS project. III. Variable stars
- Short Name:
- J/ApJ/850/137
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a census of variable stars in six M31 dwarf spheroidal satellites observed with the Hubble Space Telescope. We detect 870 RR Lyrae (RRL) stars in the fields of And I (296), II (251), III (111), XV (117), XVI (8), and XXVIII (87). We also detect a total of 15 Anomalous Cepheids, three eclipsing binaries, and seven field RRL stars compatible with being members of the M31 halo or the Giant Stellar Stream. We derive robust and homogeneous distances to the six galaxies using different methods based on the properties of the RRL stars. Working with the up-to-date set of Period-Wesenheit (I, B-I) relations published by Marconi et al., we obtain distance moduli of {mu}0=[24.49, 24.16, 24.36, 24.42, 23.70, 24.43]mag (respectively), with systematic uncertainties of 0.08mag and statistical uncertainties <0.11mag. We have considered an enlarged sample of 16 M31 satellites with published variability studies, and compared their pulsational observables (e.g., periods and amplitudes) with those of 15 Milky Way satellites for which similar data are available. The properties of the (strictly old) RRL in both satellite systems do not show any significant difference. In particular, we found a strikingly similar correlation between the mean period distribution of the fundamental RRL pulsators (RRab) and the mean metallicities of the galaxies. This indicates that the old RRL progenitors were similar at the early stage in the two environments, suggesting very similar characteristics for the earliest stages of evolution of both satellite systems.
- ID:
- ivo://CDS.VizieR/J/AcA/58/41
- Title:
- ISM polarization towards NGC 1502
- Short Name:
- J/AcA/58/41
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The polarimetry was obtained with the University of Wisconsin spectropolarimeter known as HPOL (descriptions in Wolff et al. 1996AJ....111..856W and Nordsieck and Harris 1996, ASP Conf. Ser. 97, 100; website address: http://www.sal.wisc.edu/HPOL/), on the 0.9m telescope at Pine Bluff Observatory or on the WIYN telescope at Kitt Peak.
- ID:
- ivo://CDS.VizieR/II/197
- Title:
- ISM towards IC 348 and Per OB2
- Short Name:
- II/197
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The relationship between interstellar extinction and distance in the direction of dark clouds in the areas around the open cluster IC 348 and the association Per OB2 is determined using the results of photoelectric photometry of 189 stars in the Vilnius photometric system.
- ID:
- ivo://CDS.VizieR/III/242
- Title:
- ISO Astrophysical Spectroscopic Database
- Short Name:
- III/242
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This database will eventually contain all the published infrared lines observed by ISO, the Infrared Space Observatory. At this stage only a few percent of the total content is included but it is increasing steadily. Thus what is presented at this stage is a beta-version of the final product. ISO - the Infrared Space Observatory - was operational during about 28 months, between November 1995 and May 1998, until its cooling fluid (liquid helium) burnt out (Kessler et al. 1996A&A...315L..27K). It was the first far-infrared satellite equipped with two medium and high resolution spectrometers, SWS (Short Wavelength Spectrometer, 2.38-45.2{mu}m, de Graauw et al. 1996A&A...315L..49D) and LWS (Long Wavelength Spectrometer, 43-197{mu}m, Clegg et al. 1996A&A...315L..38C). Both spectrometers could be operated in grating or Fabry-Perot mode. In addition, the two other ISO instruments also provided spectroscopic data: ISOCAM (the ISO Camera, Cesarsky et al. 1996A&A...315L..32C) had a CVF (Circular Variable Filter) mode in 3 bands covering the range 2.3-17.3{mu}m, and ISOPHOT (The Imaging Photo-Polarimeter, Lemke et al. 1996A&A...315L..64L) had a dual grating spectrometer (PHOT-S) with resolving power of order 90 in two bands (2.5-4.9{mu}m and 5.8-11.6{mu}m). Detailed information about ISO and its four ISO instruments can be found in "The ISO Handbook" available on-line at http://www.iso.vilspa.esa.es/ The novelty, the richness and the unicity of the ISO spectroscopic data is what motivated us in compiling this data in a systematic and homogeneous way in order to make it available to the whole astronomical community. No other past, current or foreseen space project will overwrite this data, hence the importance of this compilation. In addition, queries on the database content will be a useful tool for the preparation of follow-up observations with other space, airborne or ground-based observatories such as Herschel, SOFIA, ALMA, VLT and more. In this early version, the database is very incomplete. It contains about 3000 lines which represents only a few percent of the total. Each observed and published ISO spectroscopic line corresponds to a physical line in IASD with up to 39 parameter/information fields. The description of the various columns is given below.